On Fri, Dec 24, 2021 at 03:00:10PM +0100, Timo Rothenpieler wrote: > On 24.12.2021 05:32, lance.lmw...@gmail.com wrote: > > From: Limin Wang <lance.lmw...@gmail.com> > > > > Note: > > nvenc sdk will truncated user data unregistered SEI if the size > 503. > > for example, hardcode its size to 504, trace_headers will report below > > error: > > Invalid SEI message: payload_size too large (504 504 bytes). > > I'm amazed it even does that now. > Last time I tested this, encoding straight up failed if the SEI data was too > large, since the allocated packet output buffer has a fixed size, and no API > to influence that size exists.
I'm not sure whether it's for the sdk version, I'm using nv-codec-headers(sdk/11.0) and encoding is OK, but I can't find any user data unregistered SEIs although my testing is created by libx264(default the data has encoding information by the UDU SEIs, its size > 503 always). So I using trace_headers to trace the output and find out it's truncated. > > Disabling unregistered SEIs by default is probably a good call, given 99% of > the time it'll lead to unexpected failures and is not actually intended or > used by the user. Yes, if it's not truncated, you'll see the x264 encoding setting after using h264_nvenc encoding with libx264 encoding file, it's very misleading in fact. > > It IS technically an API break though, so not 100% sure on this. It's introduced by commit: cee9f9628fb, it's not correct to import unregistered SEIs to output default and the patch try to fix that. We can bump the minor version for the API change. > Ideally it'd be possible to just increase the buffer size, so the SEI data > fits. > > Where exactly did you see this 503 byte truncation happening? You can tested with libx264 output file, the size of unregistered SEIs(for encoding setting) will > 503 always, if you don't make the size <= 503, you'll see below error by trace_eaders filter. Invalid SEI message: payload_size too large (xxx 504 bytes). Note, libavcodec/cbs_sei_syntax_template.c line 262, I print out "get_bits_left(rw) / 8". I think the buffer size is OK, but nvenc sdk truncate the data after encoding. > _______________________________________________ > ffmpeg-devel mailing list > ffmpeg-devel@ffmpeg.org > https://ffmpeg.org/mailman/listinfo/ffmpeg-devel > > To unsubscribe, visit link above, or email > ffmpeg-devel-requ...@ffmpeg.org with subject "unsubscribe". -- Thanks, Limin Wang _______________________________________________ ffmpeg-devel mailing list ffmpeg-devel@ffmpeg.org https://ffmpeg.org/mailman/listinfo/ffmpeg-devel To unsubscribe, visit link above, or email ffmpeg-devel-requ...@ffmpeg.org with subject "unsubscribe".
