[FFmpeg-devel] [PATCH] avcodec/cbs_av1: don't abort when splitting Temporal Units containing OBUs with no obu_size field
James Almer
jamrial at gmail.com
Thu Nov 15 06:27:12 EET 2018
The ISOBMFF and Matroska specs allow the last OBU in a Sample/Block to have
obu_has_size_field equal to 0.
Signed-off-by: James Almer <jamrial at gmail.com>
---
See https://0x0.st/sUsU.mp4
It apparently can't be decoded with either aom or dav1d atm, but the latter
should be able to soon.
You can try remuxing it using the av1_metadata bsf after this patch while at it,
since the code to write obu_size fields unconditionally is still in place, and
that should make it decodable with either library.
For some reason cbs_av1_read_unit() is already able to handle OBUs with no
obu_size field. It was only cbs_av1_split_fragment() bailing out with them.
libavcodec/cbs_av1.c | 16 ++++++----------
1 file changed, 6 insertions(+), 10 deletions(-)
diff --git a/libavcodec/cbs_av1.c b/libavcodec/cbs_av1.c
index ed5211be19..e02bc7027a 100644
--- a/libavcodec/cbs_av1.c
+++ b/libavcodec/cbs_av1.c
@@ -788,13 +788,6 @@ static int cbs_av1_split_fragment(CodedBitstreamContext *ctx,
if (err < 0)
goto fail;
- if (!header.obu_has_size_field) {
- av_log(ctx->log_ctx, AV_LOG_ERROR, "Invalid OBU for raw "
- "stream: size field must be present.\n");
- err = AVERROR_INVALIDDATA;
- goto fail;
- }
-
if (get_bits_left(&gbc) < 8) {
av_log(ctx->log_ctx, AV_LOG_ERROR, "Invalid OBU: fragment "
"too short (%zu bytes).\n", size);
@@ -802,9 +795,12 @@ static int cbs_av1_split_fragment(CodedBitstreamContext *ctx,
goto fail;
}
- err = cbs_av1_read_leb128(ctx, &gbc, "obu_size", &obu_size);
- if (err < 0)
- goto fail;
+ if (header.obu_has_size_field) {
+ err = cbs_av1_read_leb128(ctx, &gbc, "obu_size", &obu_size);
+ if (err < 0)
+ goto fail;
+ } else
+ obu_size = size - 1 - header.obu_extension_flag;
pos = get_bits_count(&gbc);
av_assert0(pos % 8 == 0 && pos / 8 <= size);
--
2.19.1
More information about the ffmpeg-devel
mailing list