@@ -2,6 +2,9 @@ The last version increases of all libraries were on 2023-02-09
API changes, most recent first:
+2023-12-xx - xxxxxxxxxxx - lavc 60.36.100 - avcodec.h
+ Add AV_CODEC_FLAG_CLEAR.
+
2023-12-xx - xxxxxxxxxxx - lavu 58.33.100 - imguils.h
Add av_image_fill_color()
@@ -76,6 +76,20 @@ Apply interlaced motion estimation.
Use closed gop.
@item output_corrupt
Output even potentially corrupted frames.
+@item clear
+Clear the contents of the video buffer before decoding the next picture to it.
+
+Usually if only a part of a picture is affected by a decode error then the
+decoder (if it implements error concealment) tries to hide it by interpolating
+pixels from neighbouring areas or in some cases from the previous frame. Even
+without error concealment it is quite likely that the affected area will
+contain pixels from an earlier frame, due to frame pooling.
+
+For quality checking this might not be desirable, because it makes the errors
+less noticable. By using this flag, and combining it with disabled error
+concealment (@code{-ec 0}) it is possible to ensure that no leftover data from
+an earlier frame is presented in areas affected by decode errors.
+
@end table
@item time_base @var{rational number}
@@ -312,6 +312,10 @@ typedef struct RcOverride{
* loop filter.
*/
#define AV_CODEC_FLAG_LOOP_FILTER (1 << 11)
+/**
+ * Clear frame buffer contents before decoding.
+ */
+#define AV_CODEC_FLAG_CLEAR (1 << 12)
/**
* Only decode/encode grayscale.
*/
@@ -1675,6 +1675,12 @@ FF_ENABLE_DEPRECATION_WARNINGS
validate_avframe_allocation(avctx, frame);
+ if (avctx->flags & AV_CODEC_FLAG_CLEAR && avctx->codec_type == AVMEDIA_TYPE_VIDEO) {
+ uint32_t color[4] = {0};
+ ptrdiff_t linesize[4] = {frame->linesize[0], frame->linesize[1], frame->linesize[2], frame->linesize[3]};
+ av_image_fill_color(frame->data, linesize, frame->format, color, frame->width, frame->height);
+ }
+
ret = ff_attach_decode_data(frame);
if (ret < 0)
goto fail;
@@ -62,6 +62,7 @@ static const AVOption avcodec_options[] = {
{"frame_duration", "use frame durations", 0, AV_OPT_TYPE_CONST, {.i64 = AV_CODEC_FLAG_FRAME_DURATION}, .unit = "flags"},
{"pass1", "use internal 2-pass ratecontrol in first pass mode", 0, AV_OPT_TYPE_CONST, {.i64 = AV_CODEC_FLAG_PASS1 }, INT_MIN, INT_MAX, 0, "flags"},
{"pass2", "use internal 2-pass ratecontrol in second pass mode", 0, AV_OPT_TYPE_CONST, {.i64 = AV_CODEC_FLAG_PASS2 }, INT_MIN, INT_MAX, 0, "flags"},
+{"clear", "clear frames before decoding", 0, AV_OPT_TYPE_CONST, {.i64 = AV_CODEC_FLAG_CLEAR }, INT_MIN, INT_MAX, V|E|D, "flags"},
{"gray", "only decode/encode grayscale", 0, AV_OPT_TYPE_CONST, {.i64 = AV_CODEC_FLAG_GRAY }, INT_MIN, INT_MAX, V|E|D, "flags"},
{"psnr", "error[?] variables will be set during encoding", 0, AV_OPT_TYPE_CONST, {.i64 = AV_CODEC_FLAG_PSNR }, INT_MIN, INT_MAX, V|E, "flags"},
{"ildct", "use interlaced DCT", 0, AV_OPT_TYPE_CONST, {.i64 = AV_CODEC_FLAG_INTERLACED_DCT }, INT_MIN, INT_MAX, V|E, "flags"},
@@ -29,7 +29,7 @@
#include "version_major.h"
-#define LIBAVCODEC_VERSION_MINOR 35
+#define LIBAVCODEC_VERSION_MINOR 36
#define LIBAVCODEC_VERSION_MICRO 100
#define LIBAVCODEC_VERSION_INT AV_VERSION_INT(LIBAVCODEC_VERSION_MAJOR, \
Signed-off-by: Marton Balint <cus@passwd.hu> --- doc/APIchanges | 3 +++ doc/codecs.texi | 14 ++++++++++++++ libavcodec/avcodec.h | 4 ++++ libavcodec/decode.c | 6 ++++++ libavcodec/options_table.h | 1 + libavcodec/version.h | 2 +- 6 files changed, 29 insertions(+), 1 deletion(-)