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-rw-r--r--media/libtheora/include/theora/codec.h591
-rw-r--r--media/libtheora/include/theora/theora.h784
-rw-r--r--media/libtheora/include/theora/theoradec.h326
-rw-r--r--media/libtheora/include/theora/theoraenc.h540
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+/********************************************************************
+ * *
+ * THIS FILE IS PART OF THE OggTheora SOFTWARE CODEC SOURCE CODE. *
+ * USE, DISTRIBUTION AND REPRODUCTION OF THIS LIBRARY SOURCE IS *
+ * GOVERNED BY A BSD-STYLE SOURCE LICENSE INCLUDED WITH THIS SOURCE *
+ * IN 'COPYING'. PLEASE READ THESE TERMS BEFORE DISTRIBUTING. *
+ * *
+ * THE Theora SOURCE CODE IS COPYRIGHT (C) 2002-2009 *
+ * by the Xiph.Org Foundation http://www.xiph.org/ *
+ * *
+ ********************************************************************
+
+ function:
+ last mod: $Id: theora.h,v 1.8 2004/03/15 22:17:32 derf Exp $
+
+ ********************************************************************/
+
+/**\mainpage
+ *
+ * \section intro Introduction
+ *
+ * This is the documentation for <tt>libtheora</tt> C API.
+ * The current reference
+ * implementation for <a href="http://www.theora.org/">Theora</a>, a free,
+ * patent-unencumbered video codec.
+ * Theora is derived from On2's VP3 codec with additional features and
+ * integration with Ogg multimedia formats by
+ * <a href="http://www.xiph.org/">the Xiph.Org Foundation</a>.
+ * Complete documentation of the format itself is available in
+ * <a href="http://www.theora.org/doc/Theora.pdf">the Theora
+ * specification</a>.
+ *
+ * \subsection Organization
+ *
+ * The functions documented here are actually subdivided into three
+ * separate libraries:
+ * - <tt>libtheoraenc</tt> contains the encoder interface,
+ * described in \ref encfuncs.
+ * - <tt>libtheoradec</tt> contains the decoder interface and
+ * routines shared with the encoder.
+ * You must also link to this if you link to <tt>libtheoraenc</tt>.
+ * The routines in this library are described in \ref decfuncs and
+ * \ref basefuncs.
+ * - <tt>libtheora</tt> contains the \ref oldfuncs.
+ *
+ * New code should link to <tt>libtheoradec</tt> and, if using encoder
+ * features, <tt>libtheoraenc</tt>. Together these two export both
+ * the standard and the legacy API, so this is all that is needed by
+ * any code. The older <tt>libtheora</tt> library is provided just for
+ * compatibility with older build configurations.
+ *
+ * In general the recommended 1.x API symbols can be distinguished
+ * by their <tt>th_</tt> or <tt>TH_</tt> namespace prefix.
+ * The older, legacy API uses <tt>theora_</tt> or <tt>OC_</tt>
+ * prefixes instead.
+ */
+
+/**\file
+ * The shared <tt>libtheoradec</tt> and <tt>libtheoraenc</tt> C API.
+ * You don't need to include this directly.*/
+
+#if !defined(_O_THEORA_CODEC_H_)
+# define _O_THEORA_CODEC_H_ (1)
+# include <ogg/ogg.h>
+
+#if defined(__cplusplus)
+extern "C" {
+#endif
+
+
+
+/**\name Return codes*/
+/*@{*/
+/**An invalid pointer was provided.*/
+#define TH_EFAULT (-1)
+/**An invalid argument was provided.*/
+#define TH_EINVAL (-10)
+/**The contents of the header were incomplete, invalid, or unexpected.*/
+#define TH_EBADHEADER (-20)
+/**The header does not belong to a Theora stream.*/
+#define TH_ENOTFORMAT (-21)
+/**The bitstream version is too high.*/
+#define TH_EVERSION (-22)
+/**The specified function is not implemented.*/
+#define TH_EIMPL (-23)
+/**There were errors in the video data packet.*/
+#define TH_EBADPACKET (-24)
+/**The decoded packet represented a dropped frame.
+ The player can continue to display the current frame, as the contents of the
+ decoded frame buffer have not changed.*/
+#define TH_DUPFRAME (1)
+/*@}*/
+
+/**The currently defined color space tags.
+ * See <a href="http://www.theora.org/doc/Theora.pdf">the Theora
+ * specification</a>, Chapter 4, for exact details on the meaning
+ * of each of these color spaces.*/
+typedef enum{
+ /**The color space was not specified at the encoder.
+ It may be conveyed by an external means.*/
+ TH_CS_UNSPECIFIED,
+ /**A color space designed for NTSC content.*/
+ TH_CS_ITU_REC_470M,
+ /**A color space designed for PAL/SECAM content.*/
+ TH_CS_ITU_REC_470BG,
+ /**The total number of currently defined color spaces.*/
+ TH_CS_NSPACES
+}th_colorspace;
+
+/**The currently defined pixel format tags.
+ * See <a href="http://www.theora.org/doc/Theora.pdf">the Theora
+ * specification</a>, Section 4.4, for details on the precise sample
+ * locations.*/
+typedef enum{
+ /**Chroma decimation by 2 in both the X and Y directions (4:2:0).
+ The Cb and Cr chroma planes are half the width and half the
+ height of the luma plane.*/
+ TH_PF_420,
+ /**Currently reserved.*/
+ TH_PF_RSVD,
+ /**Chroma decimation by 2 in the X direction (4:2:2).
+ The Cb and Cr chroma planes are half the width of the luma plane, but full
+ height.*/
+ TH_PF_422,
+ /**No chroma decimation (4:4:4).
+ The Cb and Cr chroma planes are full width and full height.*/
+ TH_PF_444,
+ /**The total number of currently defined pixel formats.*/
+ TH_PF_NFORMATS
+}th_pixel_fmt;
+
+
+
+/**A buffer for a single color plane in an uncompressed image.
+ * This contains the image data in a left-to-right, top-down format.
+ * Each row of pixels is stored contiguously in memory, but successive
+ * rows need not be.
+ * Use \a stride to compute the offset of the next row.
+ * The encoder accepts both positive \a stride values (top-down in memory)
+ * and negative (bottom-up in memory).
+ * The decoder currently always generates images with positive strides.*/
+typedef struct{
+ /**The width of this plane.*/
+ int width;
+ /**The height of this plane.*/
+ int height;
+ /**The offset in bytes between successive rows.*/
+ int stride;
+ /**A pointer to the beginning of the first row.*/
+ unsigned char *data;
+}th_img_plane;
+
+/**A complete image buffer for an uncompressed frame.
+ * The chroma planes may be decimated by a factor of two in either
+ * direction, as indicated by th_info#pixel_fmt.
+ * The width and height of the Y' plane must be multiples of 16.
+ * They may need to be cropped for display, using the rectangle
+ * specified by th_info#pic_x, th_info#pic_y, th_info#pic_width,
+ * and th_info#pic_height.
+ * All samples are 8 bits.
+ * \note The term YUV often used to describe a colorspace is ambiguous.
+ * The exact parameters of the RGB to YUV conversion process aside, in
+ * many contexts the U and V channels actually have opposite meanings.
+ * To avoid this confusion, we are explicit: the name of the color
+ * channels are Y'CbCr, and they appear in that order, always.
+ * The prime symbol denotes that the Y channel is non-linear.
+ * Cb and Cr stand for "Chroma blue" and "Chroma red", respectively.*/
+typedef th_img_plane th_ycbcr_buffer[3];
+
+/**Theora bitstream information.
+ * This contains the basic playback parameters for a stream, and corresponds to
+ * the initial 'info' header packet.
+ * To initialize an encoder, the application fills in this structure and
+ * passes it to th_encode_alloc().
+ * A default encoding mode is chosen based on the values of the #quality and
+ * #target_bitrate fields.
+ * On decode, it is filled in by th_decode_headerin(), and then passed to
+ * th_decode_alloc().
+ *
+ * Encoded Theora frames must be a multiple of 16 in size;
+ * this is what the #frame_width and #frame_height members represent.
+ * To handle arbitrary picture sizes, a crop rectangle is specified in the
+ * #pic_x, #pic_y, #pic_width and #pic_height members.
+ *
+ * All frame buffers contain pointers to the full, padded frame.
+ * However, the current encoder <em>will not</em> reference pixels outside of
+ * the cropped picture region, and the application does not need to fill them
+ * in.
+ * The decoder <em>will</em> allocate storage for a full frame, but the
+ * application <em>should not</em> rely on the padding containing sensible
+ * data.
+ *
+ * It is also generally recommended that the offsets and sizes should still be
+ * multiples of 2 to avoid chroma sampling shifts when chroma is sub-sampled.
+ * See <a href="http://www.theora.org/doc/Theora.pdf">the Theora
+ * specification</a>, Section 4.4, for more details.
+ *
+ * Frame rate, in frames per second, is stored as a rational fraction, as is
+ * the pixel aspect ratio.
+ * Note that this refers to the aspect ratio of the individual pixels, not of
+ * the overall frame itself.
+ * The frame aspect ratio can be computed from pixel aspect ratio using the
+ * image dimensions.*/
+typedef struct{
+ /**\name Theora version
+ * Bitstream version information.*/
+ /*@{*/
+ unsigned char version_major;
+ unsigned char version_minor;
+ unsigned char version_subminor;
+ /*@}*/
+ /**The encoded frame width.
+ * This must be a multiple of 16, and less than 1048576.*/
+ ogg_uint32_t frame_width;
+ /**The encoded frame height.
+ * This must be a multiple of 16, and less than 1048576.*/
+ ogg_uint32_t frame_height;
+ /**The displayed picture width.
+ * This must be no larger than width.*/
+ ogg_uint32_t pic_width;
+ /**The displayed picture height.
+ * This must be no larger than height.*/
+ ogg_uint32_t pic_height;
+ /**The X offset of the displayed picture.
+ * This must be no larger than #frame_width-#pic_width or 255, whichever is
+ * smaller.*/
+ ogg_uint32_t pic_x;
+ /**The Y offset of the displayed picture.
+ * This must be no larger than #frame_height-#pic_height, and
+ * #frame_height-#pic_height-#pic_y must be no larger than 255.
+ * This slightly funny restriction is due to the fact that the offset is
+ * specified from the top of the image for consistency with the standard
+ * graphics left-handed coordinate system used throughout this API, while
+ * it is stored in the encoded stream as an offset from the bottom.*/
+ ogg_uint32_t pic_y;
+ /**\name Frame rate
+ * The frame rate, as a fraction.
+ * If either is 0, the frame rate is undefined.*/
+ /*@{*/
+ ogg_uint32_t fps_numerator;
+ ogg_uint32_t fps_denominator;
+ /*@}*/
+ /**\name Aspect ratio
+ * The aspect ratio of the pixels.
+ * If either value is zero, the aspect ratio is undefined.
+ * If not specified by any external means, 1:1 should be assumed.
+ * The aspect ratio of the full picture can be computed as
+ * \code
+ * aspect_numerator*pic_width/(aspect_denominator*pic_height).
+ * \endcode */
+ /*@{*/
+ ogg_uint32_t aspect_numerator;
+ ogg_uint32_t aspect_denominator;
+ /*@}*/
+ /**The color space.*/
+ th_colorspace colorspace;
+ /**The pixel format.*/
+ th_pixel_fmt pixel_fmt;
+ /**The target bit-rate in bits per second.
+ If initializing an encoder with this struct, set this field to a non-zero
+ value to activate CBR encoding by default.*/
+ int target_bitrate;
+ /**The target quality level.
+ Valid values range from 0 to 63, inclusive, with higher values giving
+ higher quality.
+ If initializing an encoder with this struct, and #target_bitrate is set
+ to zero, VBR encoding at this quality will be activated by default.*/
+ /*Currently this is set so that a qi of 0 corresponds to distortions of 24
+ times the JND, and each increase by 16 halves that value.
+ This gives us fine discrimination at low qualities, yet effective rate
+ control at high qualities.
+ The qi value 63 is special, however.
+ For this, the highest quality, we use one half of a JND for our threshold.
+ Due to the lower bounds placed on allowable quantizers in Theora, we will
+ not actually be able to achieve quality this good, but this should
+ provide as close to visually lossless quality as Theora is capable of.
+ We could lift the quantizer restrictions without breaking VP3.1
+ compatibility, but this would result in quantized coefficients that are
+ too large for the current bitstream to be able to store.
+ We'd have to redesign the token syntax to store these large coefficients,
+ which would make transcoding complex.*/
+ int quality;
+ /**The amount to shift to extract the last keyframe number from the granule
+ * position.
+ * This can be at most 31.
+ * th_info_init() will set this to a default value (currently <tt>6</tt>,
+ * which is good for streaming applications), but you can set it to 0 to
+ * make every frame a keyframe.
+ * The maximum distance between key frames is
+ * <tt>1<<#keyframe_granule_shift</tt>.
+ * The keyframe frequency can be more finely controlled with
+ * #TH_ENCCTL_SET_KEYFRAME_FREQUENCY_FORCE, which can also be adjusted
+ * during encoding (for example, to force the next frame to be a keyframe),
+ * but it cannot be set larger than the amount permitted by this field after
+ * the headers have been output.*/
+ int keyframe_granule_shift;
+}th_info;
+
+/**The comment information.
+ *
+ * This structure holds the in-stream metadata corresponding to
+ * the 'comment' header packet.
+ * The comment header is meant to be used much like someone jotting a quick
+ * note on the label of a video.
+ * It should be a short, to the point text note that can be more than a couple
+ * words, but not more than a short paragraph.
+ *
+ * The metadata is stored as a series of (tag, value) pairs, in
+ * length-encoded string vectors.
+ * The first occurrence of the '=' character delimits the tag and value.
+ * A particular tag may occur more than once, and order is significant.
+ * The character set encoding for the strings is always UTF-8, but the tag
+ * names are limited to ASCII, and treated as case-insensitive.
+ * See <a href="http://www.theora.org/doc/Theora.pdf">the Theora
+ * specification</a>, Section 6.3.3 for details.
+ *
+ * In filling in this structure, th_decode_headerin() will null-terminate
+ * the user_comment strings for safety.
+ * However, the bitstream format itself treats them as 8-bit clean vectors,
+ * possibly containing null characters, and so the length array should be
+ * treated as their authoritative length.
+ */
+typedef struct th_comment{
+ /**The array of comment string vectors.*/
+ char **user_comments;
+ /**An array of the corresponding length of each vector, in bytes.*/
+ int *comment_lengths;
+ /**The total number of comment strings.*/
+ int comments;
+ /**The null-terminated vendor string.
+ This identifies the software used to encode the stream.*/
+ char *vendor;
+}th_comment;
+
+
+
+/**A single base matrix.*/
+typedef unsigned char th_quant_base[64];
+
+/**A set of \a qi ranges.*/
+typedef struct{
+ /**The number of ranges in the set.*/
+ int nranges;
+ /**The size of each of the #nranges ranges.
+ These must sum to 63.*/
+ const int *sizes;
+ /**#nranges <tt>+1</tt> base matrices.
+ Matrices \a i and <tt>i+1</tt> form the endpoints of range \a i.*/
+ const th_quant_base *base_matrices;
+}th_quant_ranges;
+
+/**A complete set of quantization parameters.
+ The quantizer for each coefficient is calculated as:
+ \code
+ Q=MAX(MIN(qmin[qti][ci!=0],scale[ci!=0][qi]*base[qti][pli][qi][ci]/100),
+ 1024).
+ \endcode
+
+ \a qti is the quantization type index: 0 for intra, 1 for inter.
+ <tt>ci!=0</tt> is 0 for the DC coefficient and 1 for AC coefficients.
+ \a qi is the quality index, ranging between 0 (low quality) and 63 (high
+ quality).
+ \a pli is the color plane index: 0 for Y', 1 for Cb, 2 for Cr.
+ \a ci is the DCT coefficient index.
+ Coefficient indices correspond to the normal 2D DCT block
+ ordering--row-major with low frequencies first--\em not zig-zag order.
+
+ Minimum quantizers are constant, and are given by:
+ \code
+ qmin[2][2]={{4,2},{8,4}}.
+ \endcode
+
+ Parameters that can be stored in the bitstream are as follows:
+ - The two scale matrices ac_scale and dc_scale.
+ \code
+ scale[2][64]={dc_scale,ac_scale}.
+ \endcode
+ - The base matrices for each \a qi, \a qti and \a pli (up to 384 in all).
+ In order to avoid storing a full 384 base matrices, only a sparse set of
+ matrices are stored, and the rest are linearly interpolated.
+ This is done as follows.
+ For each \a qti and \a pli, a series of \a n \a qi ranges is defined.
+ The size of each \a qi range can vary arbitrarily, but they must sum to
+ 63.
+ Then, <tt>n+1</tt> matrices are specified, one for each endpoint of the
+ ranges.
+ For interpolation purposes, each range's endpoints are the first \a qi
+ value it contains and one past the last \a qi value it contains.
+ Fractional values are rounded to the nearest integer, with ties rounded
+ away from zero.
+
+ Base matrices are stored by reference, so if the same matrices are used
+ multiple times, they will only appear once in the bitstream.
+ The bitstream is also capable of omitting an entire set of ranges and
+ its associated matrices if they are the same as either the previous
+ set (indexed in row-major order) or if the inter set is the same as the
+ intra set.
+
+ - Loop filter limit values.
+ The same limits are used for the loop filter in all color planes, despite
+ potentially differing levels of quantization in each.
+
+ For the current encoder, <tt>scale[ci!=0][qi]</tt> must be no greater
+ than <tt>scale[ci!=0][qi-1]</tt> and <tt>base[qti][pli][qi][ci]</tt> must
+ be no greater than <tt>base[qti][pli][qi-1][ci]</tt>.
+ These two conditions ensure that the actual quantizer for a given \a qti,
+ \a pli, and \a ci does not increase as \a qi increases.
+ This is not required by the decoder.*/
+typedef struct{
+ /**The DC scaling factors.*/
+ ogg_uint16_t dc_scale[64];
+ /**The AC scaling factors.*/
+ ogg_uint16_t ac_scale[64];
+ /**The loop filter limit values.*/
+ unsigned char loop_filter_limits[64];
+ /**The \a qi ranges for each \a ci and \a pli.*/
+ th_quant_ranges qi_ranges[2][3];
+}th_quant_info;
+
+
+
+/**The number of Huffman tables used by Theora.*/
+#define TH_NHUFFMAN_TABLES (80)
+/**The number of DCT token values in each table.*/
+#define TH_NDCT_TOKENS (32)
+
+/**A Huffman code for a Theora DCT token.
+ * Each set of Huffman codes in a given table must form a complete, prefix-free
+ * code.
+ * There is no requirement that all the tokens in a table have a valid code,
+ * but the current encoder is not optimized to take advantage of this.
+ * If each of the five grouops of 16 tables does not contain at least one table
+ * with a code for every token, then the encoder may fail to encode certain
+ * frames.
+ * The complete table in the first group of 16 does not have to be in the same
+ * place as the complete table in the other groups, but the complete tables in
+ * the remaining four groups must all be in the same place.*/
+typedef struct{
+ /**The bit pattern for the code, with the LSbit of the pattern aligned in
+ * the LSbit of the word.*/
+ ogg_uint32_t pattern;
+ /**The number of bits in the code.
+ * This must be between 0 and 32, inclusive.*/
+ int nbits;
+}th_huff_code;
+
+
+
+/**\defgroup basefuncs Functions Shared by Encode and Decode*/
+/*@{*/
+/**\name Basic shared functions*/
+/*@{*/
+/**Retrieves a human-readable string to identify the library vendor and
+ * version.
+ * \return the version string.*/
+extern const char *th_version_string(void);
+/**Retrieves the library version number.
+ * This is the highest bitstream version that the encoder library will produce,
+ * or that the decoder library can decode.
+ * This number is composed of a 16-bit major version, 8-bit minor version
+ * and 8 bit sub-version, composed as follows:
+ * \code
+ * (VERSION_MAJOR<<16)+(VERSION_MINOR<<8)+(VERSION_SUBMINOR)
+ * \endcode
+ * \return the version number.*/
+extern ogg_uint32_t th_version_number(void);
+/**Converts a granule position to an absolute frame index, starting at
+ * <tt>0</tt>.
+ * The granule position is interpreted in the context of a given
+ * #th_enc_ctx or #th_dec_ctx handle (either will suffice).
+ * \param _encdec A previously allocated #th_enc_ctx or #th_dec_ctx
+ * handle.
+ * \param _granpos The granule position to convert.
+ * \returns The absolute frame index corresponding to \a _granpos.
+ * \retval -1 The given granule position was invalid (i.e. negative).*/
+extern ogg_int64_t th_granule_frame(void *_encdec,ogg_int64_t _granpos);
+/**Converts a granule position to an absolute time in seconds.
+ * The granule position is interpreted in the context of a given
+ * #th_enc_ctx or #th_dec_ctx handle (either will suffice).
+ * \param _encdec A previously allocated #th_enc_ctx or #th_dec_ctx
+ * handle.
+ * \param _granpos The granule position to convert.
+ * \return The absolute time in seconds corresponding to \a _granpos.
+ * This is the "end time" for the frame, or the latest time it should
+ * be displayed.
+ * It is not the presentation time.
+ * \retval -1 The given granule position was invalid (i.e. negative).*/
+extern double th_granule_time(void *_encdec,ogg_int64_t _granpos);
+/**Determines whether a Theora packet is a header or not.
+ * This function does no verification beyond checking the packet type bit, so
+ * it should not be used for bitstream identification; use
+ * th_decode_headerin() for that.
+ * As per the Theora specification, an empty (0-byte) packet is treated as a
+ * data packet (a delta frame with no coded blocks).
+ * \param _op An <tt>ogg_packet</tt> containing encoded Theora data.
+ * \retval 1 The packet is a header packet
+ * \retval 0 The packet is a video data packet.*/
+extern int th_packet_isheader(ogg_packet *_op);
+/**Determines whether a theora packet is a key frame or not.
+ * This function does no verification beyond checking the packet type and
+ * key frame bits, so it should not be used for bitstream identification; use
+ * th_decode_headerin() for that.
+ * As per the Theora specification, an empty (0-byte) packet is treated as a
+ * delta frame (with no coded blocks).
+ * \param _op An <tt>ogg_packet</tt> containing encoded Theora data.
+ * \retval 1 The packet contains a key frame.
+ * \retval 0 The packet contains a delta frame.
+ * \retval -1 The packet is not a video data packet.*/
+extern int th_packet_iskeyframe(ogg_packet *_op);
+/*@}*/
+
+
+/**\name Functions for manipulating header data*/
+/*@{*/
+/**Initializes a th_info structure.
+ * This should be called on a freshly allocated #th_info structure before
+ * attempting to use it.
+ * \param _info The #th_info struct to initialize.*/
+extern void th_info_init(th_info *_info);
+/**Clears a #th_info structure.
+ * This should be called on a #th_info structure after it is no longer
+ * needed.
+ * \param _info The #th_info struct to clear.*/
+extern void th_info_clear(th_info *_info);
+
+/**Initialize a #th_comment structure.
+ * This should be called on a freshly allocated #th_comment structure
+ * before attempting to use it.
+ * \param _tc The #th_comment struct to initialize.*/
+extern void th_comment_init(th_comment *_tc);
+/**Add a comment to an initialized #th_comment structure.
+ * \note Neither th_comment_add() nor th_comment_add_tag() support
+ * comments containing null values, although the bitstream format does
+ * support them.
+ * To add such comments you will need to manipulate the #th_comment
+ * structure directly.
+ * \param _tc The #th_comment struct to add the comment to.
+ * \param _comment Must be a null-terminated UTF-8 string containing the
+ * comment in "TAG=the value" form.*/
+extern void th_comment_add(th_comment *_tc, char *_comment);
+/**Add a comment to an initialized #th_comment structure.
+ * \note Neither th_comment_add() nor th_comment_add_tag() support
+ * comments containing null values, although the bitstream format does
+ * support them.
+ * To add such comments you will need to manipulate the #th_comment
+ * structure directly.
+ * \param _tc The #th_comment struct to add the comment to.
+ * \param _tag A null-terminated string containing the tag associated with
+ * the comment.
+ * \param _val The corresponding value as a null-terminated string.*/
+extern void th_comment_add_tag(th_comment *_tc,char *_tag,char *_val);
+/**Look up a comment value by its tag.
+ * \param _tc An initialized #th_comment structure.
+ * \param _tag The tag to look up.
+ * \param _count The instance of the tag.
+ * The same tag can appear multiple times, each with a distinct
+ * value, so an index is required to retrieve them all.
+ * The order in which these values appear is significant and
+ * should be preserved.
+ * Use th_comment_query_count() to get the legal range for
+ * the \a _count parameter.
+ * \return A pointer to the queried tag's value.
+ * This points directly to data in the #th_comment structure.
+ * It should not be modified or freed by the application, and
+ * modifications to the structure may invalidate the pointer.
+ * \retval NULL If no matching tag is found.*/
+extern char *th_comment_query(th_comment *_tc,char *_tag,int _count);
+/**Look up the number of instances of a tag.
+ * Call this first when querying for a specific tag and then iterate over the
+ * number of instances with separate calls to th_comment_query() to
+ * retrieve all the values for that tag in order.
+ * \param _tc An initialized #th_comment structure.
+ * \param _tag The tag to look up.
+ * \return The number on instances of this particular tag.*/
+extern int th_comment_query_count(th_comment *_tc,char *_tag);
+/**Clears a #th_comment structure.
+ * This should be called on a #th_comment structure after it is no longer
+ * needed.
+ * It will free all memory used by the structure members.
+ * \param _tc The #th_comment struct to clear.*/
+extern void th_comment_clear(th_comment *_tc);
+/*@}*/
+/*@}*/
+
+
+
+#if defined(__cplusplus)
+}
+#endif
+
+#endif
diff --git a/media/libtheora/include/theora/theora.h b/media/libtheora/include/theora/theora.h
new file mode 100644
index 0000000000..575a889b71
--- /dev/null
+++ b/media/libtheora/include/theora/theora.h
@@ -0,0 +1,784 @@
+/********************************************************************
+ * *
+ * THIS FILE IS PART OF THE OggTheora SOFTWARE CODEC SOURCE CODE. *
+ * USE, DISTRIBUTION AND REPRODUCTION OF THIS LIBRARY SOURCE IS *
+ * GOVERNED BY A BSD-STYLE SOURCE LICENSE INCLUDED WITH THIS SOURCE *
+ * IN 'COPYING'. PLEASE READ THESE TERMS BEFORE DISTRIBUTING. *
+ * *
+ * THE Theora SOURCE CODE IS COPYRIGHT (C) 2002-2009 *
+ * by the Xiph.Org Foundation http://www.xiph.org/ *
+ * *
+ ********************************************************************
+
+ function:
+ last mod: $Id: theora.h,v 1.17 2003/12/06 18:06:19 arc Exp $
+
+ ********************************************************************/
+
+#ifndef _O_THEORA_H_
+#define _O_THEORA_H_
+
+#ifdef __cplusplus
+extern "C"
+{
+#endif /* __cplusplus */
+
+#include <stddef.h> /* for size_t */
+
+#include <ogg/ogg.h>
+
+/** \file
+ * The libtheora pre-1.0 legacy C API.
+ *
+ * \ingroup oldfuncs
+ *
+ * \section intro Introduction
+ *
+ * This is the documentation for the libtheora legacy C API, declared in
+ * the theora.h header, which describes the old interface used before
+ * the 1.0 release. This API was widely deployed for several years and
+ * remains supported, but for new code we recommend the cleaner API
+ * declared in theoradec.h and theoraenc.h.
+ *
+ * libtheora is the reference implementation for
+ * <a href="http://www.theora.org/">Theora</a>, a free video codec.
+ * Theora is derived from On2's VP3 codec with improved integration with
+ * Ogg multimedia formats by <a href="http://www.xiph.org/">Xiph.Org</a>.
+ *
+ * \section overview Overview
+ *
+ * This library will both decode and encode theora packets to/from raw YUV
+ * frames. In either case, the packets will most likely either come from or
+ * need to be embedded in an Ogg stream. Use
+ * <a href="http://xiph.org/ogg/">libogg</a> or
+ * <a href="http://www.annodex.net/software/liboggz/index.html">liboggz</a>
+ * to extract/package these packets.
+ *
+ * \section decoding Decoding Process
+ *
+ * Decoding can be separated into the following steps:
+ * -# initialise theora_info and theora_comment structures using
+ * theora_info_init() and theora_comment_init():
+ \verbatim
+ theora_info info;
+ theora_comment comment;
+
+ theora_info_init(&info);
+ theora_comment_init(&comment);
+ \endverbatim
+ * -# retrieve header packets from Ogg stream (there should be 3) and decode
+ * into theora_info and theora_comment structures using
+ * theora_decode_header(). See \ref identification for more information on
+ * identifying which packets are theora packets.
+ \verbatim
+ int i;
+ for (i = 0; i < 3; i++)
+ {
+ (get a theora packet "op" from the Ogg stream)
+ theora_decode_header(&info, &comment, op);
+ }
+ \endverbatim
+ * -# initialise the decoder based on the information retrieved into the
+ * theora_info struct by theora_decode_header(). You will need a
+ * theora_state struct.
+ \verbatim
+ theora_state state;
+
+ theora_decode_init(&state, &info);
+ \endverbatim
+ * -# pass in packets and retrieve decoded frames! See the yuv_buffer
+ * documentation for information on how to retrieve raw YUV data.
+ \verbatim
+ yuf_buffer buffer;
+ while (last packet was not e_o_s) {
+ (get a theora packet "op" from the Ogg stream)
+ theora_decode_packetin(&state, op);
+ theora_decode_YUVout(&state, &buffer);
+ }
+ \endverbatim
+ *
+ *
+ * \subsection identification Identifying Theora Packets
+ *
+ * All streams inside an Ogg file have a unique serial_no attached to the
+ * stream. Typically, you will want to
+ * - retrieve the serial_no for each b_o_s (beginning of stream) page
+ * encountered within the Ogg file;
+ * - test the first (only) packet on that page to determine if it is a theora
+ * packet;
+ * - once you have found a theora b_o_s page then use the retrieved serial_no
+ * to identify future packets belonging to the same theora stream.
+ *
+ * Note that you \e cannot use theora_packet_isheader() to determine if a
+ * packet is a theora packet or not, as this function does not perform any
+ * checking beyond whether a header bit is present. Instead, use the
+ * theora_decode_header() function and check the return value; or examine the
+ * header bytes at the beginning of the Ogg page.
+ */
+
+
+/** \defgroup oldfuncs Legacy pre-1.0 C API */
+/* @{ */
+
+/**
+ * A YUV buffer for passing uncompressed frames to and from the codec.
+ * This holds a Y'CbCr frame in planar format. The CbCr planes can be
+ * subsampled and have their own separate dimensions and row stride
+ * offsets. Note that the strides may be negative in some
+ * configurations. For theora the width and height of the largest plane
+ * must be a multiple of 16. The actual meaningful picture size and
+ * offset are stored in the theora_info structure; frames returned by
+ * the decoder may need to be cropped for display.
+ *
+ * All samples are 8 bits. Within each plane samples are ordered by
+ * row from the top of the frame to the bottom. Within each row samples
+ * are ordered from left to right.
+ *
+ * During decode, the yuv_buffer struct is allocated by the user, but all
+ * fields (including luma and chroma pointers) are filled by the library.
+ * These pointers address library-internal memory and their contents should
+ * not be modified.
+ *
+ * Conversely, during encode the user allocates the struct and fills out all
+ * fields. The user also manages the data addressed by the luma and chroma
+ * pointers. See the encoder_example.c and dump_video.c example files in
+ * theora/examples/ for more information.
+ */
+typedef struct {
+ int y_width; /**< Width of the Y' luminance plane */
+ int y_height; /**< Height of the luminance plane */
+ int y_stride; /**< Offset in bytes between successive rows */
+
+ int uv_width; /**< Width of the Cb and Cr chroma planes */
+ int uv_height; /**< Height of the chroma planes */
+ int uv_stride; /**< Offset between successive chroma rows */
+ unsigned char *y; /**< Pointer to start of luminance data */
+ unsigned char *u; /**< Pointer to start of Cb data */
+ unsigned char *v; /**< Pointer to start of Cr data */
+
+} yuv_buffer;
+
+/**
+ * A Colorspace.
+ */
+typedef enum {
+ OC_CS_UNSPECIFIED, /**< The colorspace is unknown or unspecified */
+ OC_CS_ITU_REC_470M, /**< This is the best option for 'NTSC' content */
+ OC_CS_ITU_REC_470BG, /**< This is the best option for 'PAL' content */
+ OC_CS_NSPACES /**< This marks the end of the defined colorspaces */
+} theora_colorspace;
+
+/**
+ * A Chroma subsampling
+ *
+ * These enumerate the available chroma subsampling options supported
+ * by the theora format. See Section 4.4 of the specification for
+ * exact definitions.
+ */
+typedef enum {
+ OC_PF_420, /**< Chroma subsampling by 2 in each direction (4:2:0) */
+ OC_PF_RSVD, /**< Reserved value */
+ OC_PF_422, /**< Horizonatal chroma subsampling by 2 (4:2:2) */
+ OC_PF_444 /**< No chroma subsampling at all (4:4:4) */
+} theora_pixelformat;
+
+/**
+ * Theora bitstream info.
+ * Contains the basic playback parameters for a stream,
+ * corresponding to the initial 'info' header packet.
+ *
+ * Encoded theora frames must be a multiple of 16 in width and height.
+ * To handle other frame sizes, a crop rectangle is specified in
+ * frame_height and frame_width, offset_x and * offset_y. The offset
+ * and size should still be a multiple of 2 to avoid chroma sampling
+ * shifts. Offset values in this structure are measured from the
+ * upper left of the image.
+ *
+ * Frame rate, in frames per second, is stored as a rational
+ * fraction. Aspect ratio is also stored as a rational fraction, and
+ * refers to the aspect ratio of the frame pixels, not of the
+ * overall frame itself.
+ *
+ * See <a href="http://svn.xiph.org/trunk/theora/examples/encoder_example.c">
+ * examples/encoder_example.c</a> for usage examples of the
+ * other paramters and good default settings for the encoder parameters.
+ */
+typedef struct {
+ ogg_uint32_t width; /**< encoded frame width */
+ ogg_uint32_t height; /**< encoded frame height */
+ ogg_uint32_t frame_width; /**< display frame width */
+ ogg_uint32_t frame_height; /**< display frame height */
+ ogg_uint32_t offset_x; /**< horizontal offset of the displayed frame */
+ ogg_uint32_t offset_y; /**< vertical offset of the displayed frame */
+ ogg_uint32_t fps_numerator; /**< frame rate numerator **/
+ ogg_uint32_t fps_denominator; /**< frame rate denominator **/
+ ogg_uint32_t aspect_numerator; /**< pixel aspect ratio numerator */
+ ogg_uint32_t aspect_denominator; /**< pixel aspect ratio denominator */
+ theora_colorspace colorspace; /**< colorspace */
+ int target_bitrate; /**< nominal bitrate in bits per second */
+ int quality; /**< Nominal quality setting, 0-63 */
+ int quick_p; /**< Quick encode/decode */
+
+ /* decode only */
+ unsigned char version_major;
+ unsigned char version_minor;
+ unsigned char version_subminor;
+
+ void *codec_setup;
+
+ /* encode only */
+ int dropframes_p;
+ int keyframe_auto_p;
+ ogg_uint32_t keyframe_frequency;
+ ogg_uint32_t keyframe_frequency_force; /* also used for decode init to
+ get granpos shift correct */
+ ogg_uint32_t keyframe_data_target_bitrate;
+ ogg_int32_t keyframe_auto_threshold;
+ ogg_uint32_t keyframe_mindistance;
+ ogg_int32_t noise_sensitivity;
+ ogg_int32_t sharpness;
+
+ theora_pixelformat pixelformat; /**< chroma subsampling mode to expect */
+
+} theora_info;
+
+/** Codec internal state and context.
+ */
+typedef struct{
+ theora_info *i;
+ ogg_int64_t granulepos;
+
+ void *internal_encode;
+ void *internal_decode;
+
+} theora_state;
+
+/**
+ * Comment header metadata.
+ *
+ * This structure holds the in-stream metadata corresponding to
+ * the 'comment' header packet.
+ *
+ * Meta data is stored as a series of (tag, value) pairs, in
+ * length-encoded string vectors. The first occurence of the
+ * '=' character delimits the tag and value. A particular tag
+ * may occur more than once. The character set encoding for
+ * the strings is always UTF-8, but the tag names are limited
+ * to case-insensitive ASCII. See the spec for details.
+ *
+ * In filling in this structure, theora_decode_header() will
+ * null-terminate the user_comment strings for safety. However,
+ * the bitstream format itself treats them as 8-bit clean,
+ * and so the length array should be treated as authoritative
+ * for their length.
+ */
+typedef struct theora_comment{
+ char **user_comments; /**< An array of comment string vectors */
+ int *comment_lengths; /**< An array of corresponding string vector lengths in bytes */
+ int comments; /**< The total number of comment string vectors */
+ char *vendor; /**< The vendor string identifying the encoder, null terminated */
+
+} theora_comment;
+
+
+/**\name theora_control() codes */
+/* \anchor decctlcodes_old
+ * These are the available request codes for theora_control()
+ * when called with a decoder instance.
+ * By convention decoder control codes are odd, to distinguish
+ * them from \ref encctlcodes_old "encoder control codes" which
+ * are even.
+ *
+ * Note that since the 1.0 release, both the legacy and the final
+ * implementation accept all the same control codes, but only the
+ * final API declares the newer codes.
+ *
+ * Keep any experimental or vendor-specific values above \c 0x8000.*/
+
+/*@{*/
+
+/**Get the maximum post-processing level.
+ * The decoder supports a post-processing filter that can improve
+ * the appearance of the decoded images. This returns the highest
+ * level setting for this post-processor, corresponding to maximum
+ * improvement and computational expense.
+ */
+#define TH_DECCTL_GET_PPLEVEL_MAX (1)
+
+/**Set the post-processing level.
+ * Sets the level of post-processing to use when decoding the
+ * compressed stream. This must be a value between zero (off)
+ * and the maximum returned by TH_DECCTL_GET_PPLEVEL_MAX.
+ */
+#define TH_DECCTL_SET_PPLEVEL (3)
+
+/**Sets the maximum distance between key frames.
+ * This can be changed during an encode, but will be bounded by
+ * <tt>1<<th_info#keyframe_granule_shift</tt>.
+ * If it is set before encoding begins, th_info#keyframe_granule_shift will
+ * be enlarged appropriately.
+ *
+ * \param[in] buf <tt>ogg_uint32_t</tt>: The maximum distance between key
+ * frames.
+ * \param[out] buf <tt>ogg_uint32_t</tt>: The actual maximum distance set.
+ * \retval OC_FAULT \a theora_state or \a buf is <tt>NULL</tt>.
+ * \retval OC_EINVAL \a buf_sz is not <tt>sizeof(ogg_uint32_t)</tt>.
+ * \retval OC_IMPL Not supported by this implementation.*/
+#define TH_ENCCTL_SET_KEYFRAME_FREQUENCY_FORCE (4)
+
+/**Set the granule position.
+ * Call this after a seek, to update the internal granulepos
+ * in the decoder, to insure that subsequent frames are marked
+ * properly. If you track timestamps yourself and do not use
+ * the granule postion returned by the decoder, then you do
+ * not need to use this control.
+ */
+#define TH_DECCTL_SET_GRANPOS (5)
+
+/**\anchor encctlcodes_old */
+
+/**Sets the quantization parameters to use.
+ * The parameters are copied, not stored by reference, so they can be freed
+ * after this call.
+ * <tt>NULL</tt> may be specified to revert to the default parameters.
+ *
+ * \param[in] buf #th_quant_info
+ * \retval OC_FAULT \a theora_state is <tt>NULL</tt>.
+ * \retval OC_EINVAL Encoding has already begun, the quantization parameters
+ * are not acceptable to this version of the encoder,
+ * \a buf is <tt>NULL</tt> and \a buf_sz is not zero,
+ * or \a buf is non-<tt>NULL</tt> and \a buf_sz is
+ * not <tt>sizeof(#th_quant_info)</tt>.
+ * \retval OC_IMPL Not supported by this implementation.*/
+#define TH_ENCCTL_SET_QUANT_PARAMS (2)
+
+/**Disables any encoder features that would prevent lossless transcoding back
+ * to VP3.
+ * This primarily means disabling block-level QI values and not using 4MV mode
+ * when any of the luma blocks in a macro block are not coded.
+ * It also includes using the VP3 quantization tables and Huffman codes; if you
+ * set them explicitly after calling this function, the resulting stream will
+ * not be VP3-compatible.
+ * If you enable VP3-compatibility when encoding 4:2:2 or 4:4:4 source
+ * material, or when using a picture region smaller than the full frame (e.g.
+ * a non-multiple-of-16 width or height), then non-VP3 bitstream features will
+ * still be disabled, but the stream will still not be VP3-compatible, as VP3
+ * was not capable of encoding such formats.
+ * If you call this after encoding has already begun, then the quantization
+ * tables and codebooks cannot be changed, but the frame-level features will
+ * be enabled or disabled as requested.
+ *
+ * \param[in] buf <tt>int</tt>: a non-zero value to enable VP3 compatibility,
+ * or 0 to disable it (the default).
+ * \param[out] buf <tt>int</tt>: 1 if all bitstream features required for
+ * VP3-compatibility could be set, and 0 otherwise.
+ * The latter will be returned if the pixel format is not
+ * 4:2:0, the picture region is smaller than the full frame,
+ * or if encoding has begun, preventing the quantization
+ * tables and codebooks from being set.
+ * \retval OC_FAULT \a theora_state or \a buf is <tt>NULL</tt>.
+ * \retval OC_EINVAL \a buf_sz is not <tt>sizeof(int)</tt>.
+ * \retval OC_IMPL Not supported by this implementation.*/
+#define TH_ENCCTL_SET_VP3_COMPATIBLE (10)
+
+/**Gets the maximum speed level.
+ * Higher speed levels favor quicker encoding over better quality per bit.
+ * Depending on the encoding mode, and the internal algorithms used, quality
+ * may actually improve, but in this case bitrate will also likely increase.
+ * In any case, overall rate/distortion performance will probably decrease.
+ * The maximum value, and the meaning of each value, may change depending on
+ * the current encoding mode (VBR vs. CQI, etc.).
+ *
+ * \param[out] buf int: The maximum encoding speed level.
+ * \retval OC_FAULT \a theora_state or \a buf is <tt>NULL</tt>.
+ * \retval OC_EINVAL \a buf_sz is not <tt>sizeof(int)</tt>.
+ * \retval OC_IMPL Not supported by this implementation in the current
+ * encoding mode.*/
+#define TH_ENCCTL_GET_SPLEVEL_MAX (12)
+
+/**Sets the speed level.
+ * By default a speed value of 1 is used.
+ *
+ * \param[in] buf int: The new encoding speed level.
+ * 0 is slowest, larger values use less CPU.
+ * \retval OC_FAULT \a theora_state or \a buf is <tt>NULL</tt>.
+ * \retval OC_EINVAL \a buf_sz is not <tt>sizeof(int)</tt>, or the
+ * encoding speed level is out of bounds.
+ * The maximum encoding speed level may be
+ * implementation- and encoding mode-specific, and can be
+ * obtained via #TH_ENCCTL_GET_SPLEVEL_MAX.
+ * \retval OC_IMPL Not supported by this implementation in the current
+ * encoding mode.*/
+#define TH_ENCCTL_SET_SPLEVEL (14)
+
+/*@}*/
+
+#define OC_FAULT -1 /**< General failure */
+#define OC_EINVAL -10 /**< Library encountered invalid internal data */
+#define OC_DISABLED -11 /**< Requested action is disabled */
+#define OC_BADHEADER -20 /**< Header packet was corrupt/invalid */
+#define OC_NOTFORMAT -21 /**< Packet is not a theora packet */
+#define OC_VERSION -22 /**< Bitstream version is not handled */
+#define OC_IMPL -23 /**< Feature or action not implemented */
+#define OC_BADPACKET -24 /**< Packet is corrupt */
+#define OC_NEWPACKET -25 /**< Packet is an (ignorable) unhandled extension */
+#define OC_DUPFRAME 1 /**< Packet is a dropped frame */
+
+/**
+ * Retrieve a human-readable string to identify the encoder vendor and version.
+ * \returns A version string.
+ */
+extern const char *theora_version_string(void);
+
+/**
+ * Retrieve a 32-bit version number.
+ * This number is composed of a 16-bit major version, 8-bit minor version
+ * and 8 bit sub-version, composed as follows:
+<pre>
+ (VERSION_MAJOR<<16) + (VERSION_MINOR<<8) + (VERSION_SUB)
+</pre>
+* \returns The version number.
+*/
+extern ogg_uint32_t theora_version_number(void);
+
+/**
+ * Initialize the theora encoder.
+ * \param th The theora_state handle to initialize for encoding.
+ * \param ti A theora_info struct filled with the desired encoding parameters.
+ * \retval 0 Success
+ */
+extern int theora_encode_init(theora_state *th, theora_info *ti);
+
+/**
+ * Submit a YUV buffer to the theora encoder.
+ * \param t A theora_state handle previously initialized for encoding.
+ * \param yuv A buffer of YUV data to encode. Note that both the yuv_buffer
+ * struct and the luma/chroma buffers within should be allocated by
+ * the user.
+ * \retval OC_EINVAL Encoder is not ready, or is finished.
+ * \retval -1 The size of the given frame differs from those previously input
+ * \retval 0 Success
+ */
+extern int theora_encode_YUVin(theora_state *t, yuv_buffer *yuv);
+
+/**
+ * Request the next packet of encoded video.
+ * The encoded data is placed in a user-provided ogg_packet structure.
+ * \param t A theora_state handle previously initialized for encoding.
+ * \param last_p whether this is the last packet the encoder should produce.
+ * \param op An ogg_packet structure to fill. libtheora will set all
+ * elements of this structure, including a pointer to encoded
+ * data. The memory for the encoded data is owned by libtheora.
+ * \retval 0 No internal storage exists OR no packet is ready
+ * \retval -1 The encoding process has completed
+ * \retval 1 Success
+ */
+extern int theora_encode_packetout( theora_state *t, int last_p,
+ ogg_packet *op);
+
+/**
+ * Request a packet containing the initial header.
+ * A pointer to the header data is placed in a user-provided ogg_packet
+ * structure.
+ * \param t A theora_state handle previously initialized for encoding.
+ * \param op An ogg_packet structure to fill. libtheora will set all
+ * elements of this structure, including a pointer to the header
+ * data. The memory for the header data is owned by libtheora.
+ * \retval 0 Success
+ */
+extern int theora_encode_header(theora_state *t, ogg_packet *op);
+
+/**
+ * Request a comment header packet from provided metadata.
+ * A pointer to the comment data is placed in a user-provided ogg_packet
+ * structure.
+ * \param tc A theora_comment structure filled with the desired metadata
+ * \param op An ogg_packet structure to fill. libtheora will set all
+ * elements of this structure, including a pointer to the encoded
+ * comment data. The memory for the comment data is owned by
+ * libtheora.
+ * \retval 0 Success
+ */
+extern int theora_encode_comment(theora_comment *tc, ogg_packet *op);
+
+/**
+ * Request a packet containing the codebook tables for the stream.
+ * A pointer to the codebook data is placed in a user-provided ogg_packet
+ * structure.
+ * \param t A theora_state handle previously initialized for encoding.
+ * \param op An ogg_packet structure to fill. libtheora will set all
+ * elements of this structure, including a pointer to the codebook
+ * data. The memory for the header data is owned by libtheora.
+ * \retval 0 Success
+ */
+extern int theora_encode_tables(theora_state *t, ogg_packet *op);
+
+/**
+ * Decode an Ogg packet, with the expectation that the packet contains
+ * an initial header, comment data or codebook tables.
+ *
+ * \param ci A theora_info structure to fill. This must have been previously
+ * initialized with theora_info_init(). If \a op contains an initial
+ * header, theora_decode_header() will fill \a ci with the
+ * parsed header values. If \a op contains codebook tables,
+ * theora_decode_header() will parse these and attach an internal
+ * representation to \a ci->codec_setup.
+ * \param cc A theora_comment structure to fill. If \a op contains comment
+ * data, theora_decode_header() will fill \a cc with the parsed
+ * comments.
+ * \param op An ogg_packet structure which you expect contains an initial
+ * header, comment data or codebook tables.
+ *
+ * \retval OC_BADHEADER \a op is NULL; OR the first byte of \a op->packet
+ * has the signature of an initial packet, but op is
+ * not a b_o_s packet; OR this packet has the signature
+ * of an initial header packet, but an initial header
+ * packet has already been seen; OR this packet has the
+ * signature of a comment packet, but the initial header
+ * has not yet been seen; OR this packet has the signature
+ * of a comment packet, but contains invalid data; OR
+ * this packet has the signature of codebook tables,
+ * but the initial header or comments have not yet
+ * been seen; OR this packet has the signature of codebook
+ * tables, but contains invalid data;
+ * OR the stream being decoded has a compatible version
+ * but this packet does not have the signature of a
+ * theora initial header, comments, or codebook packet
+ * \retval OC_VERSION The packet data of \a op is an initial header with
+ * a version which is incompatible with this version of
+ * libtheora.
+ * \retval OC_NEWPACKET the stream being decoded has an incompatible (future)
+ * version and contains an unknown signature.
+ * \retval 0 Success
+ *
+ * \note The normal usage is that theora_decode_header() be called on the
+ * first three packets of a theora logical bitstream in succession.
+ */
+extern int theora_decode_header(theora_info *ci, theora_comment *cc,
+ ogg_packet *op);
+
+/**
+ * Initialize a theora_state handle for decoding.
+ * \param th The theora_state handle to initialize.
+ * \param c A theora_info struct filled with the desired decoding parameters.
+ * This is of course usually obtained from a previous call to
+ * theora_decode_header().
+ * \retval 0 Success
+ */
+extern int theora_decode_init(theora_state *th, theora_info *c);
+
+/**
+ * Input a packet containing encoded data into the theora decoder.
+ * \param th A theora_state handle previously initialized for decoding.
+ * \param op An ogg_packet containing encoded theora data.
+ * \retval 0 Success
+ * \retval OC_BADPACKET \a op does not contain encoded video data
+ */
+extern int theora_decode_packetin(theora_state *th,ogg_packet *op);
+
+/**
+ * Output the next available frame of decoded YUV data.
+ * \param th A theora_state handle previously initialized for decoding.
+ * \param yuv A yuv_buffer in which libtheora should place the decoded data.
+ * Note that the buffer struct itself is allocated by the user, but
+ * that the luma and chroma pointers will be filled in by the
+ * library. Also note that these luma and chroma regions should be
+ * considered read-only by the user.
+ * \retval 0 Success
+ */
+extern int theora_decode_YUVout(theora_state *th,yuv_buffer *yuv);
+
+/**
+ * Report whether a theora packet is a header or not
+ * This function does no verification beyond checking the header
+ * flag bit so it should not be used for bitstream identification;
+ * use theora_decode_header() for that.
+ *
+ * \param op An ogg_packet containing encoded theora data.
+ * \retval 1 The packet is a header packet
+ * \retval 0 The packet is not a header packet (and so contains frame data)
+ *
+ * Thus function was added in the 1.0alpha4 release.
+ */
+extern int theora_packet_isheader(ogg_packet *op);
+
+/**
+ * Report whether a theora packet is a keyframe or not
+ *
+ * \param op An ogg_packet containing encoded theora data.
+ * \retval 1 The packet contains a keyframe image
+ * \retval 0 The packet is contains an interframe delta
+ * \retval -1 The packet is not an image data packet at all
+ *
+ * Thus function was added in the 1.0alpha4 release.
+ */
+extern int theora_packet_iskeyframe(ogg_packet *op);
+
+/**
+ * Report the granulepos shift radix
+ *
+ * When embedded in Ogg, Theora uses a two-part granulepos,
+ * splitting the 64-bit field into two pieces. The more-significant
+ * section represents the frame count at the last keyframe,
+ * and the less-significant section represents the count of
+ * frames since the last keyframe. In this way the overall
+ * field is still non-decreasing with time, but usefully encodes
+ * a pointer to the last keyframe, which is necessary for
+ * correctly restarting decode after a seek.
+ *
+ * This function reports the number of bits used to represent
+ * the distance to the last keyframe, and thus how the granulepos
+ * field must be shifted or masked to obtain the two parts.
+ *
+ * Since libtheora returns compressed data in an ogg_packet
+ * structure, this may be generally useful even if the Theora
+ * packets are not being used in an Ogg container.
+ *
+ * \param ti A previously initialized theora_info struct
+ * \returns The bit shift dividing the two granulepos fields
+ *
+ * This function was added in the 1.0alpha5 release.
+ */
+int theora_granule_shift(theora_info *ti);
+
+/**
+ * Convert a granulepos to an absolute frame index, starting at 0.
+ * The granulepos is interpreted in the context of a given theora_state handle.
+ *
+ * Note that while the granulepos encodes the frame count (i.e. starting
+ * from 1) this call returns the frame index, starting from zero. Thus
+ * One can calculate the presentation time by multiplying the index by
+ * the rate.
+ *
+ * \param th A previously initialized theora_state handle (encode or decode)
+ * \param granulepos The granulepos to convert.
+ * \returns The frame index corresponding to \a granulepos.
+ * \retval -1 The given granulepos is undefined (i.e. negative)
+ *
+ * Thus function was added in the 1.0alpha4 release.
+ */
+extern ogg_int64_t theora_granule_frame(theora_state *th,ogg_int64_t granulepos);
+
+/**
+ * Convert a granulepos to absolute time in seconds. The granulepos is
+ * interpreted in the context of a given theora_state handle, and gives
+ * the end time of a frame's presentation as used in Ogg mux ordering.
+ *
+ * \param th A previously initialized theora_state handle (encode or decode)
+ * \param granulepos The granulepos to convert.
+ * \returns The absolute time in seconds corresponding to \a granulepos.
+ * This is the "end time" for the frame, or the latest time it should
+ * be displayed.
+ * It is not the presentation time.
+ * \retval -1. The given granulepos is undefined (i.e. negative), or
+ * \retval -1. The function has been disabled because floating
+ * point support is not available.
+ */
+extern double theora_granule_time(theora_state *th,ogg_int64_t granulepos);
+
+/**
+ * Initialize a theora_info structure. All values within the given theora_info
+ * structure are initialized, and space is allocated within libtheora for
+ * internal codec setup data.
+ * \param c A theora_info struct to initialize.
+ */
+extern void theora_info_init(theora_info *c);
+
+/**
+ * Clear a theora_info structure. All values within the given theora_info
+ * structure are cleared, and associated internal codec setup data is freed.
+ * \param c A theora_info struct to initialize.
+ */
+extern void theora_info_clear(theora_info *c);
+
+/**
+ * Free all internal data associated with a theora_state handle.
+ * \param t A theora_state handle.
+ */
+extern void theora_clear(theora_state *t);
+
+/**
+ * Initialize an allocated theora_comment structure
+ * \param tc An allocated theora_comment structure
+ **/
+extern void theora_comment_init(theora_comment *tc);
+
+/**
+ * Add a comment to an initialized theora_comment structure
+ * \param tc A previously initialized theora comment structure
+ * \param comment A null-terminated string encoding the comment in the form
+ * "TAG=the value"
+ *
+ * Neither theora_comment_add() nor theora_comment_add_tag() support
+ * comments containing null values, although the bitstream format
+ * supports this. To add such comments you will need to manipulate
+ * the theora_comment structure directly.
+ **/
+
+extern void theora_comment_add(theora_comment *tc, char *comment);
+
+/**
+ * Add a comment to an initialized theora_comment structure.
+ * \param tc A previously initialized theora comment structure
+ * \param tag A null-terminated string containing the tag
+ * associated with the comment.
+ * \param value The corresponding value as a null-terminated string
+ *
+ * Neither theora_comment_add() nor theora_comment_add_tag() support
+ * comments containing null values, although the bitstream format
+ * supports this. To add such comments you will need to manipulate
+ * the theora_comment structure directly.
+ **/
+extern void theora_comment_add_tag(theora_comment *tc,
+ char *tag, char *value);
+
+/**
+ * Look up a comment value by tag.
+ * \param tc Tn initialized theora_comment structure
+ * \param tag The tag to look up
+ * \param count The instance of the tag. The same tag can appear multiple
+ * times, each with a distinct and ordered value, so an index
+ * is required to retrieve them all.
+ * \returns A pointer to the queried tag's value
+ * \retval NULL No matching tag is found
+ *
+ * \note Use theora_comment_query_count() to get the legal range for the
+ * count parameter.
+ **/
+
+extern char *theora_comment_query(theora_comment *tc, char *tag, int count);
+
+/** Look up the number of instances of a tag.
+ * \param tc An initialized theora_comment structure
+ * \param tag The tag to look up
+ * \returns The number on instances of a particular tag.
+ *
+ * Call this first when querying for a specific tag and then interate
+ * over the number of instances with separate calls to
+ * theora_comment_query() to retrieve all instances in order.
+ **/
+extern int theora_comment_query_count(theora_comment *tc, char *tag);
+
+/**
+ * Clear an allocated theora_comment struct so that it can be freed.
+ * \param tc An allocated theora_comment structure.
+ **/
+extern void theora_comment_clear(theora_comment *tc);
+
+/**Encoder control function.
+ * This is used to provide advanced control the encoding process.
+ * \param th A #theora_state handle.
+ * \param req The control code to process.
+ * See \ref encctlcodes_old "the list of available
+ * control codes" for details.
+ * \param buf The parameters for this control code.
+ * \param buf_sz The size of the parameter buffer.*/
+extern int theora_control(theora_state *th,int req,void *buf,size_t buf_sz);
+
+/* @} */ /* end oldfuncs doxygen group */
+
+#ifdef __cplusplus
+}
+#endif /* __cplusplus */
+
+#endif /* _O_THEORA_H_ */
diff --git a/media/libtheora/include/theora/theoradec.h b/media/libtheora/include/theora/theoradec.h
new file mode 100644
index 0000000000..6177af3216
--- /dev/null
+++ b/media/libtheora/include/theora/theoradec.h
@@ -0,0 +1,326 @@
+/********************************************************************
+ * *
+ * THIS FILE IS PART OF THE OggTheora SOFTWARE CODEC SOURCE CODE. *
+ * USE, DISTRIBUTION AND REPRODUCTION OF THIS LIBRARY SOURCE IS *
+ * GOVERNED BY A BSD-STYLE SOURCE LICENSE INCLUDED WITH THIS SOURCE *
+ * IN 'COPYING'. PLEASE READ THESE TERMS BEFORE DISTRIBUTING. *
+ * *
+ * THE Theora SOURCE CODE IS COPYRIGHT (C) 2002-2009 *
+ * by the Xiph.Org Foundation http://www.xiph.org/ *
+ * *
+ ********************************************************************
+
+ function:
+ last mod: $Id: theora.h,v 1.8 2004/03/15 22:17:32 derf Exp $
+
+ ********************************************************************/
+
+/**\file
+ * The <tt>libtheoradec</tt> C decoding API.*/
+
+#if !defined(_O_THEORA_THEORADEC_H_)
+# define _O_THEORA_THEORADEC_H_ (1)
+# include <stddef.h>
+# include <ogg/ogg.h>
+# include "codec.h"
+
+#if defined(__cplusplus)
+extern "C" {
+#endif
+
+
+
+/**\name th_decode_ctl() codes
+ * \anchor decctlcodes
+ * These are the available request codes for th_decode_ctl().
+ * By convention, these are odd, to distinguish them from the
+ * \ref encctlcodes "encoder control codes".
+ * Keep any experimental or vendor-specific values above \c 0x8000.*/
+/*@{*/
+/**Gets the maximum post-processing level.
+ * The decoder supports a post-processing filter that can improve
+ * the appearance of the decoded images. This returns the highest
+ * level setting for this post-processor, corresponding to maximum
+ * improvement and computational expense.
+ *
+ * \param[out] _buf int: The maximum post-processing level.
+ * \retval TH_EFAULT \a _dec_ctx or \a _buf is <tt>NULL</tt>.
+ * \retval TH_EINVAL \a _buf_sz is not <tt>sizeof(int)</tt>.
+ * \retval TH_EIMPL Not supported by this implementation.*/
+#define TH_DECCTL_GET_PPLEVEL_MAX (1)
+/**Sets the post-processing level.
+ * By default, post-processing is disabled.
+ *
+ * Sets the level of post-processing to use when decoding the
+ * compressed stream. This must be a value between zero (off)
+ * and the maximum returned by TH_DECCTL_GET_PPLEVEL_MAX.
+ *
+ * \param[in] _buf int: The new post-processing level.
+ * 0 to disable; larger values use more CPU.
+ * \retval TH_EFAULT \a _dec_ctx or \a _buf is <tt>NULL</tt>.
+ * \retval TH_EINVAL \a _buf_sz is not <tt>sizeof(int)</tt>, or the
+ * post-processing level is out of bounds.
+ * The maximum post-processing level may be
+ * implementation-specific, and can be obtained via
+ * #TH_DECCTL_GET_PPLEVEL_MAX.
+ * \retval TH_EIMPL Not supported by this implementation.*/
+#define TH_DECCTL_SET_PPLEVEL (3)
+/**Sets the granule position.
+ * Call this after a seek, before decoding the first frame, to ensure that the
+ * proper granule position is returned for all subsequent frames.
+ * If you track timestamps yourself and do not use the granule position
+ * returned by the decoder, then you need not call this function.
+ *
+ * \param[in] _buf <tt>ogg_int64_t</tt>: The granule position of the next
+ * frame.
+ * \retval TH_EFAULT \a _dec_ctx or \a _buf is <tt>NULL</tt>.
+ * \retval TH_EINVAL \a _buf_sz is not <tt>sizeof(ogg_int64_t)</tt>, or the
+ * granule position is negative.*/
+#define TH_DECCTL_SET_GRANPOS (5)
+/**Sets the striped decode callback function.
+ * If set, this function will be called as each piece of a frame is fully
+ * decoded in th_decode_packetin().
+ * You can pass in a #th_stripe_callback with
+ * th_stripe_callback#stripe_decoded set to <tt>NULL</tt> to disable the
+ * callbacks at any point.
+ * Enabling striped decode does not prevent you from calling
+ * th_decode_ycbcr_out() after the frame is fully decoded.
+ *
+ * \param[in] _buf #th_stripe_callback: The callback parameters.
+ * \retval TH_EFAULT \a _dec_ctx or \a _buf is <tt>NULL</tt>.
+ * \retval TH_EINVAL \a _buf_sz is not
+ * <tt>sizeof(th_stripe_callback)</tt>.*/
+#define TH_DECCTL_SET_STRIPE_CB (7)
+
+/**Enables telemetry and sets the macroblock display mode */
+#define TH_DECCTL_SET_TELEMETRY_MBMODE (9)
+/**Enables telemetry and sets the motion vector display mode */
+#define TH_DECCTL_SET_TELEMETRY_MV (11)
+/**Enables telemetry and sets the adaptive quantization display mode */
+#define TH_DECCTL_SET_TELEMETRY_QI (13)
+/**Enables telemetry and sets the bitstream breakdown visualization mode */
+#define TH_DECCTL_SET_TELEMETRY_BITS (15)
+/*@}*/
+
+
+
+/**A callback function for striped decode.
+ * This is a function pointer to an application-provided function that will be
+ * called each time a section of the image is fully decoded in
+ * th_decode_packetin().
+ * This allows the application to process the section immediately, while it is
+ * still in cache.
+ * Note that the frame is decoded bottom to top, so \a _yfrag0 will steadily
+ * decrease with each call until it reaches 0, at which point the full frame
+ * is decoded.
+ * The number of fragment rows made available in each call depends on the pixel
+ * format and the number of post-processing filters enabled, and may not even
+ * be constant for the entire frame.
+ * If a non-<tt>NULL</tt> \a _granpos pointer is passed to
+ * th_decode_packetin(), the granule position for the frame will be stored
+ * in it before the first callback is made.
+ * If an entire frame is dropped (a 0-byte packet), then no callbacks will be
+ * made at all for that frame.
+ * \param _ctx An application-provided context pointer.
+ * \param _buf The image buffer for the decoded frame.
+ * \param _yfrag0 The Y coordinate of the first row of 8x8 fragments
+ * decoded.
+ * Multiply this by 8 to obtain the pixel row number in the
+ * luma plane.
+ * If the chroma planes are subsampled in the Y direction,
+ * this will always be divisible by two.
+ * \param _yfrag_end The Y coordinate of the first row of 8x8 fragments past
+ * the newly decoded section.
+ * If the chroma planes are subsampled in the Y direction,
+ * this will always be divisible by two.
+ * I.e., this section contains fragment rows
+ * <tt>\a _yfrag0 ...\a _yfrag_end -1</tt>.*/
+typedef void (*th_stripe_decoded_func)(void *_ctx,th_ycbcr_buffer _buf,
+ int _yfrag0,int _yfrag_end);
+
+/**The striped decode callback data to pass to #TH_DECCTL_SET_STRIPE_CB.*/
+typedef struct{
+ /**An application-provided context pointer.
+ * This will be passed back verbatim to the application.*/
+ void *ctx;
+ /**The callback function pointer.*/
+ th_stripe_decoded_func stripe_decoded;
+}th_stripe_callback;
+
+
+
+/**\name Decoder state
+ The following data structures are opaque, and their contents are not
+ publicly defined by this API.
+ Referring to their internals directly is unsupported, and may break without
+ warning.*/
+/*@{*/
+/**The decoder context.*/
+typedef struct th_dec_ctx th_dec_ctx;
+/**Setup information.
+ This contains auxiliary information (Huffman tables and quantization
+ parameters) decoded from the setup header by th_decode_headerin() to be
+ passed to th_decode_alloc().
+ It can be re-used to initialize any number of decoders, and can be freed
+ via th_setup_free() at any time.*/
+typedef struct th_setup_info th_setup_info;
+/*@}*/
+
+
+
+/**\defgroup decfuncs Functions for Decoding*/
+/*@{*/
+/**\name Functions for decoding
+ * You must link to <tt>libtheoradec</tt> if you use any of the
+ * functions in this section.
+ *
+ * The functions are listed in the order they are used in a typical decode.
+ * The basic steps are:
+ * - Parse the header packets by repeatedly calling th_decode_headerin().
+ * - Allocate a #th_dec_ctx handle with th_decode_alloc().
+ * - Call th_setup_free() to free any memory used for codec setup
+ * information.
+ * - Perform any additional decoder configuration with th_decode_ctl().
+ * - For each video data packet:
+ * - Submit the packet to the decoder via th_decode_packetin().
+ * - Retrieve the uncompressed video data via th_decode_ycbcr_out().
+ * - Call th_decode_free() to release all decoder memory.*/
+/*@{*/
+/**Decodes the header packets of a Theora stream.
+ * This should be called on the initial packets of the stream, in succession,
+ * until it returns <tt>0</tt>, indicating that all headers have been
+ * processed, or an error is encountered.
+ * At least three header packets are required, and additional optional header
+ * packets may follow.
+ * This can be used on the first packet of any logical stream to determine if
+ * that stream is a Theora stream.
+ * \param _info A #th_info structure to fill in.
+ * This must have been previously initialized with
+ * th_info_init().
+ * The application may immediately begin using the contents of
+ * this structure after the first header is decoded, though it
+ * must continue to be passed in on all subsequent calls.
+ * \param _tc A #th_comment structure to fill in.
+ * The application may immediately begin using the contents of
+ * this structure after the second header is decoded, though it
+ * must continue to be passed in on all subsequent calls.
+ * \param _setup Returns a pointer to additional, private setup information
+ * needed by the decoder.
+ * The contents of this pointer must be initialized to
+ * <tt>NULL</tt> on the first call, and the returned value must
+ * continue to be passed in on all subsequent calls.
+ * \param _op An <tt>ogg_packet</tt> structure which contains one of the
+ * initial packets of an Ogg logical stream.
+ * \return A positive value indicates that a Theora header was successfully
+ * processed.
+ * \retval 0 The first video data packet was encountered after all
+ * required header packets were parsed.
+ * The packet just passed in on this call should be saved
+ * and fed to th_decode_packetin() to begin decoding
+ * video data.
+ * \retval TH_EFAULT One of \a _info, \a _tc, or \a _setup was
+ * <tt>NULL</tt>.
+ * \retval TH_EBADHEADER \a _op was <tt>NULL</tt>, the packet was not the next
+ * header packet in the expected sequence, or the format
+ * of the header data was invalid.
+ * \retval TH_EVERSION The packet data was a Theora info header, but for a
+ * bitstream version not decodable with this version of
+ * <tt>libtheoradec</tt>.
+ * \retval TH_ENOTFORMAT The packet was not a Theora header.
+ */
+extern int th_decode_headerin(th_info *_info,th_comment *_tc,
+ th_setup_info **_setup,ogg_packet *_op);
+/**Allocates a decoder instance.
+ *
+ * <b>Security Warning:</b> The Theora format supports very large frame sizes,
+ * potentially even larger than the address space of a 32-bit machine, and
+ * creating a decoder context allocates the space for several frames of data.
+ * If the allocation fails here, your program will crash, possibly at some
+ * future point because the OS kernel returned a valid memory range and will
+ * only fail when it tries to map the pages in it the first time they are
+ * used.
+ * Even if it succeeds, you may experience a denial of service if the frame
+ * size is large enough to cause excessive paging.
+ * If you are integrating libtheora in a larger application where such things
+ * are undesirable, it is highly recommended that you check the frame size in
+ * \a _info before calling this function and refuse to decode streams where it
+ * is larger than some reasonable maximum.
+ * libtheora will not check this for you, because there may be machines that
+ * can handle such streams and applications that wish to.
+ * \param _info A #th_info struct filled via th_decode_headerin().
+ * \param _setup A #th_setup_info handle returned via
+ * th_decode_headerin().
+ * \return The initialized #th_dec_ctx handle.
+ * \retval NULL If the decoding parameters were invalid.*/
+extern th_dec_ctx *th_decode_alloc(const th_info *_info,
+ const th_setup_info *_setup);
+/**Releases all storage used for the decoder setup information.
+ * This should be called after you no longer want to create any decoders for
+ * a stream whose headers you have parsed with th_decode_headerin().
+ * \param _setup The setup information to free.
+ * This can safely be <tt>NULL</tt>.*/
+extern void th_setup_free(th_setup_info *_setup);
+/**Decoder control function.
+ * This is used to provide advanced control of the decoding process.
+ * \param _dec A #th_dec_ctx handle.
+ * \param _req The control code to process.
+ * See \ref decctlcodes "the list of available control codes"
+ * for details.
+ * \param _buf The parameters for this control code.
+ * \param _buf_sz The size of the parameter buffer.*/
+extern int th_decode_ctl(th_dec_ctx *_dec,int _req,void *_buf,
+ size_t _buf_sz);
+/**Submits a packet containing encoded video data to the decoder.
+ * \param _dec A #th_dec_ctx handle.
+ * \param _op An <tt>ogg_packet</tt> containing encoded video data.
+ * \param _granpos Returns the granule position of the decoded packet.
+ * If non-<tt>NULL</tt>, the granule position for this specific
+ * packet is stored in this location.
+ * This is computed incrementally from previously decoded
+ * packets.
+ * After a seek, the correct granule position must be set via
+ * #TH_DECCTL_SET_GRANPOS for this to work properly.
+ * \retval 0 Success.
+ * A new decoded frame can be retrieved by calling
+ * th_decode_ycbcr_out().
+ * \retval TH_DUPFRAME The packet represented a dropped frame (either a
+ * 0-byte frame or an INTER frame with no coded blocks).
+ * The player can skip the call to th_decode_ycbcr_out(),
+ * as the contents of the decoded frame buffer have not
+ * changed.
+ * \retval TH_EFAULT \a _dec or \a _op was <tt>NULL</tt>.
+ * \retval TH_EBADPACKET \a _op does not contain encoded video data.
+ * \retval TH_EIMPL The video data uses bitstream features which this
+ * library does not support.*/
+extern int th_decode_packetin(th_dec_ctx *_dec,const ogg_packet *_op,
+ ogg_int64_t *_granpos);
+/**Outputs the next available frame of decoded Y'CbCr data.
+ * If a striped decode callback has been set with #TH_DECCTL_SET_STRIPE_CB,
+ * then the application does not need to call this function.
+ * \param _dec A #th_dec_ctx handle.
+ * \param _ycbcr A video buffer structure to fill in.
+ * <tt>libtheoradec</tt> will fill in all the members of this
+ * structure, including the pointers to the uncompressed video
+ * data.
+ * The memory for this video data is owned by
+ * <tt>libtheoradec</tt>.
+ * It may be freed or overwritten without notification when
+ * subsequent frames are decoded.
+ * \retval 0 Success
+ * \retval TH_EFAULT \a _dec or \a _ycbcr was <tt>NULL</tt>.
+ */
+extern int th_decode_ycbcr_out(th_dec_ctx *_dec,
+ th_ycbcr_buffer _ycbcr);
+/**Frees an allocated decoder instance.
+ * \param _dec A #th_dec_ctx handle.*/
+extern void th_decode_free(th_dec_ctx *_dec);
+/*@}*/
+/*@}*/
+
+
+
+#if defined(__cplusplus)
+}
+#endif
+
+#endif
diff --git a/media/libtheora/include/theora/theoraenc.h b/media/libtheora/include/theora/theoraenc.h
new file mode 100644
index 0000000000..721ea89b9d
--- /dev/null
+++ b/media/libtheora/include/theora/theoraenc.h
@@ -0,0 +1,540 @@
+/********************************************************************
+ * *
+ * THIS FILE IS PART OF THE OggTheora SOFTWARE CODEC SOURCE CODE. *
+ * USE, DISTRIBUTION AND REPRODUCTION OF THIS LIBRARY SOURCE IS *
+ * GOVERNED BY A BSD-STYLE SOURCE LICENSE INCLUDED WITH THIS SOURCE *
+ * IN 'COPYING'. PLEASE READ THESE TERMS BEFORE DISTRIBUTING. *
+ * *
+ * THE Theora SOURCE CODE IS COPYRIGHT (C) 2002-2009 *
+ * by the Xiph.Org Foundation http://www.xiph.org/ *
+ * *
+ ********************************************************************
+
+ function:
+ last mod: $Id: theora.h,v 1.8 2004/03/15 22:17:32 derf Exp $
+
+ ********************************************************************/
+
+/**\file
+ * The <tt>libtheoraenc</tt> C encoding API.*/
+
+#if !defined(_O_THEORA_THEORAENC_H_)
+# define _O_THEORA_THEORAENC_H_ (1)
+# include <stddef.h>
+# include <ogg/ogg.h>
+# include "codec.h"
+
+#if defined(__cplusplus)
+extern "C" {
+#endif
+
+
+
+/**\name th_encode_ctl() codes
+ * \anchor encctlcodes
+ * These are the available request codes for th_encode_ctl().
+ * By convention, these are even, to distinguish them from the
+ * \ref decctlcodes "decoder control codes".
+ * Keep any experimental or vendor-specific values above \c 0x8000.*/
+/*@{*/
+/**Sets the Huffman tables to use.
+ * The tables are copied, not stored by reference, so they can be freed after
+ * this call.
+ * <tt>NULL</tt> may be specified to revert to the default tables.
+ *
+ * \param[in] _buf <tt>#th_huff_code[#TH_NHUFFMAN_TABLES][#TH_NDCT_TOKENS]</tt>
+ * \retval TH_EFAULT \a _enc is <tt>NULL</tt>.
+ * \retval TH_EINVAL Encoding has already begun or one or more of the given
+ * tables is not full or prefix-free, \a _buf is
+ * <tt>NULL</tt> and \a _buf_sz is not zero, or \a _buf is
+ * non-<tt>NULL</tt> and \a _buf_sz is not
+ * <tt>sizeof(#th_huff_code)*#TH_NHUFFMAN_TABLES*#TH_NDCT_TOKENS</tt>.
+ * \retval TH_EIMPL Not supported by this implementation.*/
+#define TH_ENCCTL_SET_HUFFMAN_CODES (0)
+/**Sets the quantization parameters to use.
+ * The parameters are copied, not stored by reference, so they can be freed
+ * after this call.
+ * <tt>NULL</tt> may be specified to revert to the default parameters.
+ *
+ * \param[in] _buf #th_quant_info
+ * \retval TH_EFAULT \a _enc is <tt>NULL</tt>.
+ * \retval TH_EINVAL Encoding has already begun, \a _buf is
+ * <tt>NULL</tt> and \a _buf_sz is not zero,
+ * or \a _buf is non-<tt>NULL</tt> and
+ * \a _buf_sz is not <tt>sizeof(#th_quant_info)</tt>.
+ * \retval TH_EIMPL Not supported by this implementation.*/
+#define TH_ENCCTL_SET_QUANT_PARAMS (2)
+/**Sets the maximum distance between key frames.
+ * This can be changed during an encode, but will be bounded by
+ * <tt>1<<th_info#keyframe_granule_shift</tt>.
+ * If it is set before encoding begins, th_info#keyframe_granule_shift will
+ * be enlarged appropriately.
+ *
+ * \param[in] _buf <tt>ogg_uint32_t</tt>: The maximum distance between key
+ * frames.
+ * \param[out] _buf <tt>ogg_uint32_t</tt>: The actual maximum distance set.
+ * \retval TH_EFAULT \a _enc or \a _buf is <tt>NULL</tt>.
+ * \retval TH_EINVAL \a _buf_sz is not <tt>sizeof(ogg_uint32_t)</tt>.
+ * \retval TH_EIMPL Not supported by this implementation.*/
+#define TH_ENCCTL_SET_KEYFRAME_FREQUENCY_FORCE (4)
+/**Disables any encoder features that would prevent lossless transcoding back
+ * to VP3.
+ * This primarily means disabling block-adaptive quantization and always coding
+ * all four luma blocks in a macro block when 4MV is used.
+ * It also includes using the VP3 quantization tables and Huffman codes; if you
+ * set them explicitly after calling this function, the resulting stream will
+ * not be VP3-compatible.
+ * If you enable VP3-compatibility when encoding 4:2:2 or 4:4:4 source
+ * material, or when using a picture region smaller than the full frame (e.g.
+ * a non-multiple-of-16 width or height), then non-VP3 bitstream features will
+ * still be disabled, but the stream will still not be VP3-compatible, as VP3
+ * was not capable of encoding such formats.
+ * If you call this after encoding has already begun, then the quantization
+ * tables and codebooks cannot be changed, but the frame-level features will
+ * be enabled or disabled as requested.
+ *
+ * \param[in] _buf <tt>int</tt>: a non-zero value to enable VP3 compatibility,
+ * or 0 to disable it (the default).
+ * \param[out] _buf <tt>int</tt>: 1 if all bitstream features required for
+ * VP3-compatibility could be set, and 0 otherwise.
+ * The latter will be returned if the pixel format is not
+ * 4:2:0, the picture region is smaller than the full frame,
+ * or if encoding has begun, preventing the quantization
+ * tables and codebooks from being set.
+ * \retval TH_EFAULT \a _enc or \a _buf is <tt>NULL</tt>.
+ * \retval TH_EINVAL \a _buf_sz is not <tt>sizeof(int)</tt>.
+ * \retval TH_EIMPL Not supported by this implementation.*/
+#define TH_ENCCTL_SET_VP3_COMPATIBLE (10)
+/**Gets the maximum speed level.
+ * Higher speed levels favor quicker encoding over better quality per bit.
+ * Depending on the encoding mode, and the internal algorithms used, quality
+ * may actually improve, but in this case bitrate will also likely increase.
+ * In any case, overall rate/distortion performance will probably decrease.
+ * The maximum value, and the meaning of each value, may change depending on
+ * the current encoding mode (VBR vs. constant quality, etc.).
+ *
+ * \param[out] _buf <tt>int</tt>: The maximum encoding speed level.
+ * \retval TH_EFAULT \a _enc or \a _buf is <tt>NULL</tt>.
+ * \retval TH_EINVAL \a _buf_sz is not <tt>sizeof(int)</tt>.
+ * \retval TH_EIMPL Not supported by this implementation in the current
+ * encoding mode.*/
+#define TH_ENCCTL_GET_SPLEVEL_MAX (12)
+/**Sets the speed level.
+ * The current speed level may be retrieved using #TH_ENCCTL_GET_SPLEVEL.
+ *
+ * \param[in] _buf <tt>int</tt>: The new encoding speed level.
+ * 0 is slowest, larger values use less CPU.
+ * \retval TH_EFAULT \a _enc or \a _buf is <tt>NULL</tt>.
+ * \retval TH_EINVAL \a _buf_sz is not <tt>sizeof(int)</tt>, or the
+ * encoding speed level is out of bounds.
+ * The maximum encoding speed level may be
+ * implementation- and encoding mode-specific, and can be
+ * obtained via #TH_ENCCTL_GET_SPLEVEL_MAX.
+ * \retval TH_EIMPL Not supported by this implementation in the current
+ * encoding mode.*/
+#define TH_ENCCTL_SET_SPLEVEL (14)
+/**Gets the current speed level.
+ * The default speed level may vary according to encoder implementation, but if
+ * this control code is not supported (it returns #TH_EIMPL), the default may
+ * be assumed to be the slowest available speed (0).
+ * The maximum encoding speed level may be implementation- and encoding
+ * mode-specific, and can be obtained via #TH_ENCCTL_GET_SPLEVEL_MAX.
+ *
+ * \param[out] _buf <tt>int</tt>: The current encoding speed level.
+ * 0 is slowest, larger values use less CPU.
+ * \retval TH_EFAULT \a _enc or \a _buf is <tt>NULL</tt>.
+ * \retval TH_EINVAL \a _buf_sz is not <tt>sizeof(int)</tt>.
+ * \retval TH_EIMPL Not supported by this implementation in the current
+ * encoding mode.*/
+#define TH_ENCCTL_GET_SPLEVEL (16)
+/**Sets the number of duplicates of the next frame to produce.
+ * Although libtheora can encode duplicate frames very cheaply, it costs some
+ * amount of CPU to detect them, and a run of duplicates cannot span a
+ * keyframe boundary.
+ * This control code tells the encoder to produce the specified number of extra
+ * duplicates of the next frame.
+ * This allows the encoder to make smarter keyframe placement decisions and
+ * rate control decisions, and reduces CPU usage as well, when compared to
+ * just submitting the same frame for encoding multiple times.
+ * This setting only applies to the next frame submitted for encoding.
+ * You MUST call th_encode_packetout() repeatedly until it returns 0, or the
+ * extra duplicate frames will be lost.
+ *
+ * \param[in] _buf <tt>int</tt>: The number of duplicates to produce.
+ * If this is negative or zero, no duplicates will be produced.
+ * \retval TH_EFAULT \a _enc or \a _buf is <tt>NULL</tt>.
+ * \retval TH_EINVAL \a _buf_sz is not <tt>sizeof(int)</tt>, or the
+ * number of duplicates is greater than or equal to the
+ * maximum keyframe interval.
+ * In the latter case, NO duplicate frames will be produced.
+ * You must ensure that the maximum keyframe interval is set
+ * larger than the maximum number of duplicates you will
+ * ever wish to insert prior to encoding.
+ * \retval TH_EIMPL Not supported by this implementation in the current
+ * encoding mode.*/
+#define TH_ENCCTL_SET_DUP_COUNT (18)
+/**Modifies the default bitrate management behavior.
+ * Use to allow or disallow frame dropping, and to enable or disable capping
+ * bit reservoir overflows and underflows.
+ * See \ref encctlcodes "the list of available flags".
+ * The flags are set by default to
+ * <tt>#TH_RATECTL_DROP_FRAMES|#TH_RATECTL_CAP_OVERFLOW</tt>.
+ *
+ * \param[in] _buf <tt>int</tt>: Any combination of
+ * \ref ratectlflags "the available flags":
+ * - #TH_RATECTL_DROP_FRAMES: Enable frame dropping.
+ * - #TH_RATECTL_CAP_OVERFLOW: Don't bank excess bits for later
+ * use.
+ * - #TH_RATECTL_CAP_UNDERFLOW: Don't try to make up shortfalls
+ * later.
+ * \retval TH_EFAULT \a _enc or \a _buf is <tt>NULL</tt>.
+ * \retval TH_EINVAL \a _buf_sz is not <tt>sizeof(int)</tt> or rate control
+ * is not enabled.
+ * \retval TH_EIMPL Not supported by this implementation in the current
+ * encoding mode.*/
+#define TH_ENCCTL_SET_RATE_FLAGS (20)
+/**Sets the size of the bitrate management bit reservoir as a function
+ * of number of frames.
+ * The reservoir size affects how quickly bitrate management reacts to
+ * instantaneous changes in the video complexity.
+ * Larger reservoirs react more slowly, and provide better overall quality, but
+ * require more buffering by a client, adding more latency to live streams.
+ * By default, libtheora sets the reservoir to the maximum distance between
+ * keyframes, subject to a minimum and maximum limit.
+ * This call may be used to increase or decrease the reservoir, increasing or
+ * decreasing the allowed temporary variance in bitrate.
+ * An implementation may impose some limits on the size of a reservoir it can
+ * handle, in which case the actual reservoir size may not be exactly what was
+ * requested.
+ * The actual value set will be returned.
+ *
+ * \param[in] _buf <tt>int</tt>: Requested size of the reservoir measured in
+ * frames.
+ * \param[out] _buf <tt>int</tt>: The actual size of the reservoir set.
+ * \retval TH_EFAULT \a _enc or \a _buf is <tt>NULL</tt>.
+ * \retval TH_EINVAL \a _buf_sz is not <tt>sizeof(int)</tt>, or rate control
+ * is not enabled. The buffer has an implementation
+ * defined minimum and maximum size and the value in _buf
+ * will be adjusted to match the actual value set.
+ * \retval TH_EIMPL Not supported by this implementation in the current
+ * encoding mode.*/
+#define TH_ENCCTL_SET_RATE_BUFFER (22)
+/**Enable pass 1 of two-pass encoding mode and retrieve the first pass metrics.
+ * Pass 1 mode must be enabled before the first frame is encoded, and a target
+ * bitrate must have already been specified to the encoder.
+ * Although this does not have to be the exact rate that will be used in the
+ * second pass, closer values may produce better results.
+ * The first call returns the size of the two-pass header data, along with some
+ * placeholder content, and sets the encoder into pass 1 mode implicitly.
+ * This call sets the encoder to pass 1 mode implicitly.
+ * Then, a subsequent call must be made after each call to
+ * th_encode_ycbcr_in() to retrieve the metrics for that frame.
+ * An additional, final call must be made to retrieve the summary data,
+ * containing such information as the total number of frames, etc.
+ * This must be stored in place of the placeholder data that was returned
+ * in the first call, before the frame metrics data.
+ * All of this data must be presented back to the encoder during pass 2 using
+ * #TH_ENCCTL_2PASS_IN.
+ *
+ * \param[out] <tt>char *</tt>_buf: Returns a pointer to internal storage
+ * containing the two pass metrics data.
+ * This storage is only valid until the next call, or until the
+ * encoder context is freed, and must be copied by the
+ * application.
+ * \retval >=0 The number of bytes of metric data available in the
+ * returned buffer.
+ * \retval TH_EFAULT \a _enc or \a _buf is <tt>NULL</tt>.
+ * \retval TH_EINVAL \a _buf_sz is not <tt>sizeof(char *)</tt>, no target
+ * bitrate has been set, or the first call was made after
+ * the first frame was submitted for encoding.
+ * \retval TH_EIMPL Not supported by this implementation.*/
+#define TH_ENCCTL_2PASS_OUT (24)
+/**Submits two-pass encoding metric data collected the first encoding pass to
+ * the second pass.
+ * The first call must be made before the first frame is encoded, and a target
+ * bitrate must have already been specified to the encoder.
+ * It sets the encoder to pass 2 mode implicitly; this cannot be disabled.
+ * The encoder may require reading data from some or all of the frames in
+ * advance, depending on, e.g., the reservoir size used in the second pass.
+ * You must call this function repeatedly before each frame to provide data
+ * until either a) it fails to consume all of the data presented or b) all of
+ * the pass 1 data has been consumed.
+ * In the first case, you must save the remaining data to be presented after
+ * the next frame.
+ * You can call this function with a NULL argument to get an upper bound on
+ * the number of bytes that will be required before the next frame.
+ *
+ * When pass 2 is first enabled, the default bit reservoir is set to the entire
+ * file; this gives maximum flexibility but can lead to very high peak rates.
+ * You can subsequently set it to another value with #TH_ENCCTL_SET_RATE_BUFFER
+ * (e.g., to set it to the keyframe interval for non-live streaming), however,
+ * you may then need to provide more data before the next frame.
+ *
+ * \param[in] _buf <tt>char[]</tt>: A buffer containing the data returned by
+ * #TH_ENCCTL_2PASS_OUT in pass 1.
+ * You may pass <tt>NULL</tt> for \a _buf to return an upper
+ * bound on the number of additional bytes needed before the
+ * next frame.
+ * The summary data returned at the end of pass 1 must be at
+ * the head of the buffer on the first call with a
+ * non-<tt>NULL</tt> \a _buf, and the placeholder data
+ * returned at the start of pass 1 should be omitted.
+ * After each call you should advance this buffer by the number
+ * of bytes consumed.
+ * \retval >0 The number of bytes of metric data required/consumed.
+ * \retval 0 No more data is required before the next frame.
+ * \retval TH_EFAULT \a _enc is <tt>NULL</tt>.
+ * \retval TH_EINVAL No target bitrate has been set, or the first call was
+ * made after the first frame was submitted for
+ * encoding.
+ * \retval TH_ENOTFORMAT The data did not appear to be pass 1 from a compatible
+ * implementation of this library.
+ * \retval TH_EBADHEADER The data was invalid; this may be returned when
+ * attempting to read an aborted pass 1 file that still
+ * has the placeholder data in place of the summary
+ * data.
+ * \retval TH_EIMPL Not supported by this implementation.*/
+#define TH_ENCCTL_2PASS_IN (26)
+/**Sets the current encoding quality.
+ * This is only valid so long as no bitrate has been specified, either through
+ * the #th_info struct used to initialize the encoder or through
+ * #TH_ENCCTL_SET_BITRATE (this restriction may be relaxed in a future
+ * version).
+ * If it is set before the headers are emitted, the target quality encoded in
+ * them will be updated.
+ *
+ * \param[in] _buf <tt>int</tt>: The new target quality, in the range 0...63,
+ * inclusive.
+ * \retval 0 Success.
+ * \retval TH_EFAULT \a _enc or \a _buf is <tt>NULL</tt>.
+ * \retval TH_EINVAL A target bitrate has already been specified, or the
+ * quality index was not in the range 0...63.
+ * \retval TH_EIMPL Not supported by this implementation.*/
+#define TH_ENCCTL_SET_QUALITY (28)
+/**Sets the current encoding bitrate.
+ * Once a bitrate is set, the encoder must use a rate-controlled mode for all
+ * future frames (this restriction may be relaxed in a future version).
+ * If it is set before the headers are emitted, the target bitrate encoded in
+ * them will be updated.
+ * Due to the buffer delay, the exact bitrate of each section of the encode is
+ * not guaranteed.
+ * The encoder may have already used more bits than allowed for the frames it
+ * has encoded, expecting to make them up in future frames, or it may have
+ * used fewer, holding the excess in reserve.
+ * The exact transition between the two bitrates is not well-defined by this
+ * API, but may be affected by flags set with #TH_ENCCTL_SET_RATE_FLAGS.
+ * After a number of frames equal to the buffer delay, one may expect further
+ * output to average at the target bitrate.
+ *
+ * \param[in] _buf <tt>long</tt>: The new target bitrate, in bits per second.
+ * \retval 0 Success.
+ * \retval TH_EFAULT \a _enc or \a _buf is <tt>NULL</tt>.
+ * \retval TH_EINVAL The target bitrate was not positive.
+ * \retval TH_EIMPL Not supported by this implementation.*/
+#define TH_ENCCTL_SET_BITRATE (30)
+/**Sets the configuration to be compatible with that from the given setup
+ * header.
+ * This sets the Huffman codebooks and quantization parameters to match those
+ * found in the given setup header.
+ * This guarantees that packets encoded by this encoder will be decodable using
+ * a decoder configured with the passed-in setup header.
+ * It does <em>not</em> guarantee that th_encode_flushheader() will produce a
+ * bit-identical setup header, only that they will be compatible.
+ * If you need a bit-identical setup header, then use the one you passed into
+ * this command, and not the one returned by th_encode_flushheader().
+ *
+ * This also does <em>not</em> enable or disable VP3 compatibility; that is not
+ * signaled in the setup header (or anywhere else in the encoded stream), and
+ * is controlled independently by the #TH_ENCCTL_SET_VP3_COMPATIBLE function.
+ * If you wish to enable VP3 compatibility mode <em>and</em> want the codebooks
+ * and quantization parameters to match the given setup header, you should
+ * enable VP3 compatibility before invoking this command, otherwise the
+ * codebooks and quantization parameters will be reset to the VP3 defaults.
+ *
+ * The current encoder does not support Huffman codebooks which do not contain
+ * codewords for all 32 tokens.
+ * Such codebooks are legal, according to the specification, but cannot be
+ * configured with this function.
+ *
+ * \param[in] _buf <tt>unsigned char[]</tt>: The encoded setup header to copy
+ * the configuration from.
+ * This should be the original,
+ * undecoded setup header packet,
+ * and <em>not</em> a #th_setup_info
+ * structure filled in by
+ * th_decode_headerin().
+ * \retval TH_EFAULT \a _enc or \a _buf is <tt>NULL</tt>.
+ * \retval TH_EINVAL Encoding has already begun, so the codebooks and
+ * quantization parameters cannot be changed, or the
+ * data in the setup header was not supported by this
+ * encoder.
+ * \retval TH_EBADHEADER \a _buf did not contain a valid setup header packet.
+ * \retval TH_ENOTFORMAT \a _buf did not contain a Theora header at all.
+ * \retval TH_EIMPL Not supported by this implementation.*/
+#define TH_ENCCTL_SET_COMPAT_CONFIG (32)
+
+/*@}*/
+
+
+/**\name TH_ENCCTL_SET_RATE_FLAGS flags
+ * \anchor ratectlflags
+ * These are the flags available for use with #TH_ENCCTL_SET_RATE_FLAGS.*/
+/*@{*/
+/**Drop frames to keep within bitrate buffer constraints.
+ * This can have a severe impact on quality, but is the only way to ensure that
+ * bitrate targets are met at low rates during sudden bursts of activity.*/
+#define TH_RATECTL_DROP_FRAMES (0x1)
+/**Ignore bitrate buffer overflows.
+ * If the encoder uses so few bits that the reservoir of available bits
+ * overflows, ignore the excess.
+ * The encoder will not try to use these extra bits in future frames.
+ * At high rates this may cause the result to be undersized, but allows a
+ * client to play the stream using a finite buffer; it should normally be
+ * enabled.*/
+#define TH_RATECTL_CAP_OVERFLOW (0x2)
+/**Ignore bitrate buffer underflows.
+ * If the encoder uses so many bits that the reservoir of available bits
+ * underflows, ignore the deficit.
+ * The encoder will not try to make up these extra bits in future frames.
+ * At low rates this may cause the result to be oversized; it should normally
+ * be disabled.*/
+#define TH_RATECTL_CAP_UNDERFLOW (0x4)
+/*@}*/
+
+
+
+/**The quantization parameters used by VP3.*/
+extern const th_quant_info TH_VP31_QUANT_INFO;
+
+/**The Huffman tables used by VP3.*/
+extern const th_huff_code
+ TH_VP31_HUFF_CODES[TH_NHUFFMAN_TABLES][TH_NDCT_TOKENS];
+
+
+
+/**\name Encoder state
+ The following data structure is opaque, and its contents are not publicly
+ defined by this API.
+ Referring to its internals directly is unsupported, and may break without
+ warning.*/
+/*@{*/
+/**The encoder context.*/
+typedef struct th_enc_ctx th_enc_ctx;
+/*@}*/
+
+
+
+/**\defgroup encfuncs Functions for Encoding*/
+/*@{*/
+/**\name Functions for encoding
+ * You must link to <tt>libtheoraenc</tt> and <tt>libtheoradec</tt>
+ * if you use any of the functions in this section.
+ *
+ * The functions are listed in the order they are used in a typical encode.
+ * The basic steps are:
+ * - Fill in a #th_info structure with details on the format of the video you
+ * wish to encode.
+ * - Allocate a #th_enc_ctx handle with th_encode_alloc().
+ * - Perform any additional encoder configuration required with
+ * th_encode_ctl().
+ * - Repeatedly call th_encode_flushheader() to retrieve all the header
+ * packets.
+ * - For each uncompressed frame:
+ * - Submit the uncompressed frame via th_encode_ycbcr_in()
+ * - Repeatedly call th_encode_packetout() to retrieve any video data packets
+ * that are ready.
+ * - Call th_encode_free() to release all encoder memory.*/
+/*@{*/
+/**Allocates an encoder instance.
+ * \param _info A #th_info struct filled with the desired encoding parameters.
+ * \return The initialized #th_enc_ctx handle.
+ * \retval NULL If the encoding parameters were invalid.*/
+extern th_enc_ctx *th_encode_alloc(const th_info *_info);
+/**Encoder control function.
+ * This is used to provide advanced control the encoding process.
+ * \param _enc A #th_enc_ctx handle.
+ * \param _req The control code to process.
+ * See \ref encctlcodes "the list of available control codes"
+ * for details.
+ * \param _buf The parameters for this control code.
+ * \param _buf_sz The size of the parameter buffer.*/
+extern int th_encode_ctl(th_enc_ctx *_enc,int _req,void *_buf,size_t _buf_sz);
+/**Outputs the next header packet.
+ * This should be called repeatedly after encoder initialization until it
+ * returns 0 in order to get all of the header packets, in order, before
+ * encoding actual video data.
+ * \param _enc A #th_enc_ctx handle.
+ * \param _comments The metadata to place in the comment header, when it is
+ * encoded.
+ * \param _op An <tt>ogg_packet</tt> structure to fill.
+ * All of the elements of this structure will be set,
+ * including a pointer to the header data.
+ * The memory for the header data is owned by
+ * <tt>libtheoraenc</tt>, and may be invalidated when the
+ * next encoder function is called.
+ * \return A positive value indicates that a header packet was successfully
+ * produced.
+ * \retval 0 No packet was produced, and no more header packets remain.
+ * \retval TH_EFAULT \a _enc, \a _comments, or \a _op was <tt>NULL</tt>.*/
+extern int th_encode_flushheader(th_enc_ctx *_enc,
+ th_comment *_comments,ogg_packet *_op);
+/**Submits an uncompressed frame to the encoder.
+ * \param _enc A #th_enc_ctx handle.
+ * \param _ycbcr A buffer of Y'CbCr data to encode.
+ * If the width and height of the buffer matches the frame size
+ * the encoder was initialized with, the encoder will only
+ * reference the portion inside the picture region.
+ * Any data outside this region will be ignored, and need not map
+ * to a valid address.
+ * Alternatively, you can pass a buffer equal to the size of the
+ * picture region, if this is less than the full frame size.
+ * When using subsampled chroma planes, odd picture sizes or odd
+ * picture offsets may require an unexpected chroma plane size,
+ * and their use is generally discouraged, as they will not be
+ * well-supported by players and other media frameworks.
+ * See Section 4.4 of
+ * <a href="http://www.theora.org/doc/Theora.pdf">the Theora
+ * specification</a> for details if you wish to use them anyway.
+ * \retval 0 Success.
+ * \retval TH_EFAULT \a _enc or \a _ycbcr is <tt>NULL</tt>.
+ * \retval TH_EINVAL The buffer size matches neither the frame size nor the
+ * picture size the encoder was initialized with, or
+ * encoding has already completed.*/
+extern int th_encode_ycbcr_in(th_enc_ctx *_enc,th_ycbcr_buffer _ycbcr);
+/**Retrieves encoded video data packets.
+ * This should be called repeatedly after each frame is submitted to flush any
+ * encoded packets, until it returns 0.
+ * The encoder will not buffer these packets as subsequent frames are
+ * compressed, so a failure to do so will result in lost video data.
+ * \note Currently the encoder operates in a one-frame-in, one-packet-out
+ * manner.
+ * However, this may be changed in the future.
+ * \param _enc A #th_enc_ctx handle.
+ * \param _last Set this flag to a non-zero value if no more uncompressed
+ * frames will be submitted.
+ * This ensures that a proper EOS flag is set on the last packet.
+ * \param _op An <tt>ogg_packet</tt> structure to fill.
+ * All of the elements of this structure will be set, including a
+ * pointer to the video data.
+ * The memory for the video data is owned by
+ * <tt>libtheoraenc</tt>, and may be invalidated when the next
+ * encoder function is called.
+ * \return A positive value indicates that a video data packet was successfully
+ * produced.
+ * \retval 0 No packet was produced, and no more encoded video data
+ * remains.
+ * \retval TH_EFAULT \a _enc or \a _op was <tt>NULL</tt>.*/
+extern int th_encode_packetout(th_enc_ctx *_enc,int _last,ogg_packet *_op);
+/**Frees an allocated encoder instance.
+ * \param _enc A #th_enc_ctx handle.*/
+extern void th_encode_free(th_enc_ctx *_enc);
+/*@}*/
+/*@}*/
+
+
+
+#if defined(__cplusplus)
+}
+#endif
+
+#endif