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Diffstat (limited to 'media/libwebp/utils/rescaler_utils.c')
-rw-r--r--media/libwebp/utils/rescaler_utils.c122
1 files changed, 67 insertions, 55 deletions
diff --git a/media/libwebp/utils/rescaler_utils.c b/media/libwebp/utils/rescaler_utils.c
index 6e384f5078..3b64e27525 100644
--- a/media/libwebp/utils/rescaler_utils.c
+++ b/media/libwebp/utils/rescaler_utils.c
@@ -12,66 +12,74 @@
// Author: Skal (pascal.massimino@gmail.com)
#include <assert.h>
+#include <limits.h>
#include <stdlib.h>
#include <string.h>
#include "../dsp/dsp.h"
#include "../utils/rescaler_utils.h"
+#include "../utils/utils.h"
//------------------------------------------------------------------------------
-void WebPRescalerInit(WebPRescaler* const wrk, int src_width, int src_height,
- uint8_t* const dst,
- int dst_width, int dst_height, int dst_stride,
- int num_channels, rescaler_t* const work) {
+int WebPRescalerInit(WebPRescaler* const rescaler,
+ int src_width, int src_height,
+ uint8_t* const dst,
+ int dst_width, int dst_height, int dst_stride,
+ int num_channels, rescaler_t* const work) {
const int x_add = src_width, x_sub = dst_width;
const int y_add = src_height, y_sub = dst_height;
- wrk->x_expand = (src_width < dst_width);
- wrk->y_expand = (src_height < dst_height);
- wrk->src_width = src_width;
- wrk->src_height = src_height;
- wrk->dst_width = dst_width;
- wrk->dst_height = dst_height;
- wrk->src_y = 0;
- wrk->dst_y = 0;
- wrk->dst = dst;
- wrk->dst_stride = dst_stride;
- wrk->num_channels = num_channels;
+ const uint64_t total_size = 2ull * dst_width * num_channels * sizeof(*work);
+ if (!CheckSizeOverflow(total_size)) return 0;
+
+ rescaler->x_expand = (src_width < dst_width);
+ rescaler->y_expand = (src_height < dst_height);
+ rescaler->src_width = src_width;
+ rescaler->src_height = src_height;
+ rescaler->dst_width = dst_width;
+ rescaler->dst_height = dst_height;
+ rescaler->src_y = 0;
+ rescaler->dst_y = 0;
+ rescaler->dst = dst;
+ rescaler->dst_stride = dst_stride;
+ rescaler->num_channels = num_channels;
// for 'x_expand', we use bilinear interpolation
- wrk->x_add = wrk->x_expand ? (x_sub - 1) : x_add;
- wrk->x_sub = wrk->x_expand ? (x_add - 1) : x_sub;
- if (!wrk->x_expand) { // fx_scale is not used otherwise
- wrk->fx_scale = WEBP_RESCALER_FRAC(1, wrk->x_sub);
+ rescaler->x_add = rescaler->x_expand ? (x_sub - 1) : x_add;
+ rescaler->x_sub = rescaler->x_expand ? (x_add - 1) : x_sub;
+ if (!rescaler->x_expand) { // fx_scale is not used otherwise
+ rescaler->fx_scale = WEBP_RESCALER_FRAC(1, rescaler->x_sub);
}
// vertical scaling parameters
- wrk->y_add = wrk->y_expand ? y_add - 1 : y_add;
- wrk->y_sub = wrk->y_expand ? y_sub - 1 : y_sub;
- wrk->y_accum = wrk->y_expand ? wrk->y_sub : wrk->y_add;
- if (!wrk->y_expand) {
+ rescaler->y_add = rescaler->y_expand ? y_add - 1 : y_add;
+ rescaler->y_sub = rescaler->y_expand ? y_sub - 1 : y_sub;
+ rescaler->y_accum = rescaler->y_expand ? rescaler->y_sub : rescaler->y_add;
+ if (!rescaler->y_expand) {
// This is WEBP_RESCALER_FRAC(dst_height, x_add * y_add) without the cast.
- // Its value is <= WEBP_RESCALER_ONE, because dst_height <= wrk->y_add, and
- // wrk->x_add >= 1;
- const uint64_t ratio =
- (uint64_t)dst_height * WEBP_RESCALER_ONE / (wrk->x_add * wrk->y_add);
+ // Its value is <= WEBP_RESCALER_ONE, because dst_height <= rescaler->y_add
+ // and rescaler->x_add >= 1;
+ const uint64_t num = (uint64_t)dst_height * WEBP_RESCALER_ONE;
+ const uint64_t den = (uint64_t)rescaler->x_add * rescaler->y_add;
+ const uint64_t ratio = num / den;
if (ratio != (uint32_t)ratio) {
// When ratio == WEBP_RESCALER_ONE, we can't represent the ratio with the
// current fixed-point precision. This happens when src_height ==
- // wrk->y_add (which == src_height), and wrk->x_add == 1.
+ // rescaler->y_add (which == src_height), and rescaler->x_add == 1.
// => We special-case fxy_scale = 0, in WebPRescalerExportRow().
- wrk->fxy_scale = 0;
+ rescaler->fxy_scale = 0;
} else {
- wrk->fxy_scale = (uint32_t)ratio;
+ rescaler->fxy_scale = (uint32_t)ratio;
}
- wrk->fy_scale = WEBP_RESCALER_FRAC(1, wrk->y_sub);
+ rescaler->fy_scale = WEBP_RESCALER_FRAC(1, rescaler->y_sub);
} else {
- wrk->fy_scale = WEBP_RESCALER_FRAC(1, wrk->x_add);
- // wrk->fxy_scale is unused here.
+ rescaler->fy_scale = WEBP_RESCALER_FRAC(1, rescaler->x_add);
+ // rescaler->fxy_scale is unused here.
}
- wrk->irow = work;
- wrk->frow = work + num_channels * dst_width;
- memset(work, 0, 2 * dst_width * num_channels * sizeof(*work));
+ rescaler->irow = work;
+ rescaler->frow = work + num_channels * dst_width;
+ memset(work, 0, (size_t)total_size);
WebPRescalerDspInit();
+ return 1;
}
int WebPRescalerGetScaledDimensions(int src_width, int src_height,
@@ -82,19 +90,20 @@ int WebPRescalerGetScaledDimensions(int src_width, int src_height,
{
int width = *scaled_width;
int height = *scaled_height;
+ const int max_size = INT_MAX / 2;
// if width is unspecified, scale original proportionally to height ratio.
- if (width == 0) {
+ if (width == 0 && src_height > 0) {
width =
- (int)(((uint64_t)src_width * height + src_height / 2) / src_height);
+ (int)(((uint64_t)src_width * height + src_height - 1) / src_height);
}
// if height is unspecified, scale original proportionally to width ratio.
- if (height == 0) {
+ if (height == 0 && src_width > 0) {
height =
- (int)(((uint64_t)src_height * width + src_width / 2) / src_width);
+ (int)(((uint64_t)src_height * width + src_width - 1) / src_width);
}
// Check if the overall dimensions still make sense.
- if (width <= 0 || height <= 0) {
+ if (width <= 0 || height <= 0 || width > max_size || height > max_size) {
return 0;
}
@@ -107,31 +116,34 @@ int WebPRescalerGetScaledDimensions(int src_width, int src_height,
//------------------------------------------------------------------------------
// all-in-one calls
-int WebPRescaleNeededLines(const WebPRescaler* const wrk, int max_num_lines) {
- const int num_lines = (wrk->y_accum + wrk->y_sub - 1) / wrk->y_sub;
+int WebPRescaleNeededLines(const WebPRescaler* const rescaler,
+ int max_num_lines) {
+ const int num_lines =
+ (rescaler->y_accum + rescaler->y_sub - 1) / rescaler->y_sub;
return (num_lines > max_num_lines) ? max_num_lines : num_lines;
}
-int WebPRescalerImport(WebPRescaler* const wrk, int num_lines,
+int WebPRescalerImport(WebPRescaler* const rescaler, int num_lines,
const uint8_t* src, int src_stride) {
int total_imported = 0;
- while (total_imported < num_lines && !WebPRescalerHasPendingOutput(wrk)) {
- if (wrk->y_expand) {
- rescaler_t* const tmp = wrk->irow;
- wrk->irow = wrk->frow;
- wrk->frow = tmp;
+ while (total_imported < num_lines &&
+ !WebPRescalerHasPendingOutput(rescaler)) {
+ if (rescaler->y_expand) {
+ rescaler_t* const tmp = rescaler->irow;
+ rescaler->irow = rescaler->frow;
+ rescaler->frow = tmp;
}
- WebPRescalerImportRow(wrk, src);
- if (!wrk->y_expand) { // Accumulate the contribution of the new row.
+ WebPRescalerImportRow(rescaler, src);
+ if (!rescaler->y_expand) { // Accumulate the contribution of the new row.
int x;
- for (x = 0; x < wrk->num_channels * wrk->dst_width; ++x) {
- wrk->irow[x] += wrk->frow[x];
+ for (x = 0; x < rescaler->num_channels * rescaler->dst_width; ++x) {
+ rescaler->irow[x] += rescaler->frow[x];
}
}
- ++wrk->src_y;
+ ++rescaler->src_y;
src += src_stride;
++total_imported;
- wrk->y_accum -= wrk->y_sub;
+ rescaler->y_accum -= rescaler->y_sub;
}
return total_imported;
}