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Diffstat (limited to 'libs/ffvpx/libavcodec/get_bits.h')
-rw-r--r--libs/ffvpx/libavcodec/get_bits.h281
1 files changed, 267 insertions, 14 deletions
diff --git a/libs/ffvpx/libavcodec/get_bits.h b/libs/ffvpx/libavcodec/get_bits.h
index 56ef5f0cb..c4ab60774 100644
--- a/libs/ffvpx/libavcodec/get_bits.h
+++ b/libs/ffvpx/libavcodec/get_bits.h
@@ -1,5 +1,6 @@
/*
- * copyright (c) 2004 Michael Niedermayer <michaelni@gmx.at>
+ * Copyright (c) 2004 Michael Niedermayer <michaelni@gmx.at>
+ * Copyright (c) 2016 Alexandra Hájková
*
* This file is part of FFmpeg.
*
@@ -53,13 +54,25 @@
#define UNCHECKED_BITSTREAM_READER !CONFIG_SAFE_BITSTREAM_READER
#endif
+#ifndef CACHED_BITSTREAM_READER
+#define CACHED_BITSTREAM_READER 0
+#endif
+
typedef struct GetBitContext {
const uint8_t *buffer, *buffer_end;
+#if CACHED_BITSTREAM_READER
+ uint64_t cache;
+ unsigned bits_left;
+#endif
int index;
int size_in_bits;
int size_in_bits_plus8;
} GetBitContext;
+static inline unsigned int get_bits(GetBitContext *s, int n);
+static inline void skip_bits(GetBitContext *s, int n);
+static inline unsigned int show_bits(GetBitContext *s, int n);
+
/* Bitstream reader API docs:
* name
* arbitrary name which is used as prefix for the internal variables
@@ -107,12 +120,16 @@ typedef struct GetBitContext {
* For examples see get_bits, show_bits, skip_bits, get_vlc.
*/
-#ifdef LONG_BITSTREAM_READER
+#if CACHED_BITSTREAM_READER
+# define MIN_CACHE_BITS 64
+#elif defined LONG_BITSTREAM_READER
# define MIN_CACHE_BITS 32
#else
# define MIN_CACHE_BITS 25
#endif
+#if !CACHED_BITSTREAM_READER
+
#define OPEN_READER_NOSIZE(name, gb) \
unsigned int name ## _index = (gb)->index; \
unsigned int av_unused name ## _cache
@@ -197,10 +214,72 @@ typedef struct GetBitContext {
#define GET_CACHE(name, gb) ((uint32_t) name ## _cache)
+#endif
+
static inline int get_bits_count(const GetBitContext *s)
{
+#if CACHED_BITSTREAM_READER
+ return s->index - s->bits_left;
+#else
return s->index;
+#endif
+}
+
+#if CACHED_BITSTREAM_READER
+static inline void refill_32(GetBitContext *s, int is_le)
+{
+#if !UNCHECKED_BITSTREAM_READER
+ if (s->index >> 3 >= s->buffer_end - s->buffer)
+ return;
+#endif
+
+ if (is_le)
+ s->cache = (uint64_t)AV_RL32(s->buffer + (s->index >> 3)) << s->bits_left | s->cache;
+ else
+ s->cache = s->cache | (uint64_t)AV_RB32(s->buffer + (s->index >> 3)) << (32 - s->bits_left);
+ s->index += 32;
+ s->bits_left += 32;
+}
+
+static inline void refill_64(GetBitContext *s, int is_le)
+{
+#if !UNCHECKED_BITSTREAM_READER
+ if (s->index >> 3 >= s->buffer_end - s->buffer)
+ return;
+#endif
+
+ if (is_le)
+ s->cache = AV_RL64(s->buffer + (s->index >> 3));
+ else
+ s->cache = AV_RB64(s->buffer + (s->index >> 3));
+ s->index += 64;
+ s->bits_left = 64;
+}
+
+static inline uint64_t get_val(GetBitContext *s, unsigned n, int is_le)
+{
+ uint64_t ret;
+ av_assert2(n>0 && n<=63);
+ if (is_le) {
+ ret = s->cache & ((UINT64_C(1) << n) - 1);
+ s->cache >>= n;
+ } else {
+ ret = s->cache >> (64 - n);
+ s->cache <<= n;
+ }
+ s->bits_left -= n;
+ return ret;
+}
+
+static inline unsigned show_val(const GetBitContext *s, unsigned n)
+{
+#ifdef BITSTREAM_READER_LE
+ return s->cache & ((UINT64_C(1) << n) - 1);
+#else
+ return s->cache >> (64 - n);
+#endif
}
+#endif
/**
* Skips the specified number of bits.
@@ -211,13 +290,29 @@ static inline int get_bits_count(const GetBitContext *s)
*/
static inline void skip_bits_long(GetBitContext *s, int n)
{
+#if CACHED_BITSTREAM_READER
+ skip_bits(s, n);
+#else
#if UNCHECKED_BITSTREAM_READER
s->index += n;
#else
s->index += av_clip(n, -s->index, s->size_in_bits_plus8 - s->index);
#endif
+#endif
}
+#if CACHED_BITSTREAM_READER
+static inline void skip_remaining(GetBitContext *s, unsigned n)
+{
+#ifdef BITSTREAM_READER_LE
+ s->cache >>= n;
+#else
+ s->cache <<= n;
+#endif
+ s->bits_left -= n;
+}
+#endif
+
/**
* Read MPEG-1 dc-style VLC (sign bit + mantissa with no MSB).
* if MSB not set it is negative
@@ -225,6 +320,13 @@ static inline void skip_bits_long(GetBitContext *s, int n)
*/
static inline int get_xbits(GetBitContext *s, int n)
{
+#if CACHED_BITSTREAM_READER
+ int32_t cache = show_bits(s, 32);
+ int sign = ~cache >> 31;
+ skip_remaining(s, n);
+
+ return ((((uint32_t)(sign ^ cache)) >> (32 - n)) ^ sign) - sign;
+#else
register int sign;
register int32_t cache;
OPEN_READER(re, s);
@@ -235,8 +337,10 @@ static inline int get_xbits(GetBitContext *s, int n)
LAST_SKIP_BITS(re, s, n);
CLOSE_READER(re, s);
return (NEG_USR32(sign ^ cache, n) ^ sign) - sign;
+#endif
}
+#if !CACHED_BITSTREAM_READER
static inline int get_xbits_le(GetBitContext *s, int n)
{
register int sign;
@@ -250,16 +354,22 @@ static inline int get_xbits_le(GetBitContext *s, int n)
CLOSE_READER(re, s);
return (zero_extend(sign ^ cache, n) ^ sign) - sign;
}
+#endif
static inline int get_sbits(GetBitContext *s, int n)
{
register int tmp;
+#if CACHED_BITSTREAM_READER
+ av_assert2(n>0 && n<=25);
+ tmp = sign_extend(get_bits(s, n), n);
+#else
OPEN_READER(re, s);
av_assert2(n>0 && n<=25);
UPDATE_CACHE(re, s);
tmp = SHOW_SBITS(re, s, n);
LAST_SKIP_BITS(re, s, n);
CLOSE_READER(re, s);
+#endif
return tmp;
}
@@ -268,13 +378,34 @@ static inline int get_sbits(GetBitContext *s, int n)
*/
static inline unsigned int get_bits(GetBitContext *s, int n)
{
- register int tmp;
+ register unsigned int tmp;
+#if CACHED_BITSTREAM_READER
+
+ av_assert2(n>0 && n<=32);
+ if (n > s->bits_left) {
+#ifdef BITSTREAM_READER_LE
+ refill_32(s, 1);
+#else
+ refill_32(s, 0);
+#endif
+ if (s->bits_left < 32)
+ s->bits_left = n;
+ }
+
+#ifdef BITSTREAM_READER_LE
+ tmp = get_val(s, n, 1);
+#else
+ tmp = get_val(s, n, 0);
+#endif
+#else
OPEN_READER(re, s);
av_assert2(n>0 && n<=25);
UPDATE_CACHE(re, s);
tmp = SHOW_UBITS(re, s, n);
LAST_SKIP_BITS(re, s, n);
CLOSE_READER(re, s);
+#endif
+ av_assert2(tmp < UINT64_C(1) << n);
return tmp;
}
@@ -288,6 +419,16 @@ static av_always_inline int get_bitsz(GetBitContext *s, int n)
static inline unsigned int get_bits_le(GetBitContext *s, int n)
{
+#if CACHED_BITSTREAM_READER
+ av_assert2(n>0 && n<=32);
+ if (n > s->bits_left) {
+ refill_32(s, 1);
+ if (s->bits_left < 32)
+ s->bits_left = n;
+ }
+
+ return get_val(s, n, 1);
+#else
register int tmp;
OPEN_READER(re, s);
av_assert2(n>0 && n<=25);
@@ -296,6 +437,7 @@ static inline unsigned int get_bits_le(GetBitContext *s, int n)
LAST_SKIP_BITS(re, s, n);
CLOSE_READER(re, s);
return tmp;
+#endif
}
/**
@@ -303,23 +445,72 @@ static inline unsigned int get_bits_le(GetBitContext *s, int n)
*/
static inline unsigned int show_bits(GetBitContext *s, int n)
{
- register int tmp;
+ register unsigned int tmp;
+#if CACHED_BITSTREAM_READER
+ if (n > s->bits_left)
+#ifdef BITSTREAM_READER_LE
+ refill_32(s, 1);
+#else
+ refill_32(s, 0);
+#endif
+
+ tmp = show_val(s, n);
+#else
OPEN_READER_NOSIZE(re, s);
av_assert2(n>0 && n<=25);
UPDATE_CACHE(re, s);
tmp = SHOW_UBITS(re, s, n);
+#endif
return tmp;
}
static inline void skip_bits(GetBitContext *s, int n)
{
+#if CACHED_BITSTREAM_READER
+ if (n < s->bits_left)
+ skip_remaining(s, n);
+ else {
+ n -= s->bits_left;
+ s->cache = 0;
+ s->bits_left = 0;
+
+ if (n >= 64) {
+ unsigned skip = (n / 8) * 8;
+
+ n -= skip;
+ s->index += skip;
+ }
+#ifdef BITSTREAM_READER_LE
+ refill_64(s, 1);
+#else
+ refill_64(s, 0);
+#endif
+ if (n)
+ skip_remaining(s, n);
+ }
+#else
OPEN_READER(re, s);
LAST_SKIP_BITS(re, s, n);
CLOSE_READER(re, s);
+#endif
}
static inline unsigned int get_bits1(GetBitContext *s)
{
+#if CACHED_BITSTREAM_READER
+ if (!s->bits_left)
+#ifdef BITSTREAM_READER_LE
+ refill_64(s, 1);
+#else
+ refill_64(s, 0);
+#endif
+
+#ifdef BITSTREAM_READER_LE
+ return get_val(s, 1, 1);
+#else
+ return get_val(s, 1, 0);
+#endif
+#else
unsigned int index = s->index;
uint8_t result = s->buffer[index >> 3];
#ifdef BITSTREAM_READER_LE
@@ -336,6 +527,7 @@ static inline unsigned int get_bits1(GetBitContext *s)
s->index = index;
return result;
+#endif
}
static inline unsigned int show_bits1(GetBitContext *s)
@@ -356,6 +548,10 @@ static inline unsigned int get_bits_long(GetBitContext *s, int n)
av_assert2(n>=0 && n<=32);
if (!n) {
return 0;
+#if CACHED_BITSTREAM_READER
+ }
+ return get_bits(s, n);
+#else
} else if (n <= MIN_CACHE_BITS) {
return get_bits(s, n);
} else {
@@ -367,6 +563,7 @@ static inline unsigned int get_bits_long(GetBitContext *s, int n)
return ret | get_bits(s, n - 16);
#endif
}
+#endif
}
/**
@@ -422,16 +619,8 @@ static inline int check_marker(void *logctx, GetBitContext *s, const char *msg)
return bit;
}
-/**
- * Initialize GetBitContext.
- * @param buffer bitstream buffer, must be AV_INPUT_BUFFER_PADDING_SIZE bytes
- * larger than the actual read bits because some optimized bitstream
- * readers read 32 or 64 bit at once and could read over the end
- * @param bit_size the size of the buffer in bits
- * @return 0 on success, AVERROR_INVALIDDATA if the buffer_size would overflow.
- */
-static inline int init_get_bits(GetBitContext *s, const uint8_t *buffer,
- int bit_size)
+static inline int init_get_bits_xe(GetBitContext *s, const uint8_t *buffer,
+ int bit_size, int is_le)
{
int buffer_size;
int ret = 0;
@@ -450,6 +639,12 @@ static inline int init_get_bits(GetBitContext *s, const uint8_t *buffer,
s->buffer_end = buffer + buffer_size;
s->index = 0;
+#if CACHED_BITSTREAM_READER
+ s->cache = 0;
+ s->bits_left = 0;
+ refill_64(s, is_le);
+#endif
+
return ret;
}
@@ -458,6 +653,24 @@ static inline int init_get_bits(GetBitContext *s, const uint8_t *buffer,
* @param buffer bitstream buffer, must be AV_INPUT_BUFFER_PADDING_SIZE bytes
* larger than the actual read bits because some optimized bitstream
* readers read 32 or 64 bit at once and could read over the end
+ * @param bit_size the size of the buffer in bits
+ * @return 0 on success, AVERROR_INVALIDDATA if the buffer_size would overflow.
+ */
+static inline int init_get_bits(GetBitContext *s, const uint8_t *buffer,
+ int bit_size)
+{
+#ifdef BITSTREAM_READER_LE
+ return init_get_bits_xe(s, buffer, bit_size, 1);
+#else
+ return init_get_bits_xe(s, buffer, bit_size, 0);
+#endif
+}
+
+/**
+ * Initialize GetBitContext.
+ * @param buffer bitstream buffer, must be AV_INPUT_BUFFER_PADDING_SIZE bytes
+ * larger than the actual read bits because some optimized bitstream
+ * readers read 32 or 64 bit at once and could read over the end
* @param byte_size the size of the buffer in bytes
* @return 0 on success, AVERROR_INVALIDDATA if the buffer_size would overflow.
*/
@@ -469,6 +682,14 @@ static inline int init_get_bits8(GetBitContext *s, const uint8_t *buffer,
return init_get_bits(s, buffer, byte_size * 8);
}
+static inline int init_get_bits8_le(GetBitContext *s, const uint8_t *buffer,
+ int byte_size)
+{
+ if (byte_size > INT_MAX / 8 || byte_size < 0)
+ byte_size = -1;
+ return init_get_bits_xe(s, buffer, byte_size * 8, 1);
+}
+
static inline const uint8_t *align_get_bits(GetBitContext *s)
{
int n = -get_bits_count(s) & 7;
@@ -551,6 +772,19 @@ static inline const uint8_t *align_get_bits(GetBitContext *s)
SKIP_BITS(name, gb, n); \
} while (0)
+/* Return the LUT element for the given bitstream configuration. */
+static inline int set_idx(GetBitContext *s, int code, int *n, int *nb_bits,
+ VLC_TYPE (*table)[2])
+{
+ unsigned idx;
+
+ *nb_bits = -*n;
+ idx = show_bits(s, *nb_bits) + code;
+ *n = table[idx][1];
+
+ return table[idx][0];
+}
+
/**
* Parse a vlc code.
* @param bits is the number of bits which will be read at once, must be
@@ -563,6 +797,24 @@ static inline const uint8_t *align_get_bits(GetBitContext *s)
static av_always_inline int get_vlc2(GetBitContext *s, VLC_TYPE (*table)[2],
int bits, int max_depth)
{
+#if CACHED_BITSTREAM_READER
+ int nb_bits;
+ unsigned idx = show_bits(s, bits);
+ int code = table[idx][0];
+ int n = table[idx][1];
+
+ if (max_depth > 1 && n < 0) {
+ skip_remaining(s, bits);
+ code = set_idx(s, code, &n, &nb_bits, table);
+ if (max_depth > 2 && n < 0) {
+ skip_remaining(s, nb_bits);
+ code = set_idx(s, code, &n, &nb_bits, table);
+ }
+ }
+ skip_remaining(s, n);
+
+ return code;
+#else
int code;
OPEN_READER(re, s);
@@ -573,6 +825,7 @@ static av_always_inline int get_vlc2(GetBitContext *s, VLC_TYPE (*table)[2],
CLOSE_READER(re, s);
return code;
+#endif
}
static inline int decode012(GetBitContext *gb)
generated by cgit v1.2.3 (git 2.26.2) at 2024-11-09 17:09:50 +0000