On Fri, 1 Mar 2019 at 05:30, Michael Niedermayer wrote: > When data is missing (in live streaming or otherwise) it under > almost all cases cannot be losslessly recovered. So this use matches > the definition
Yes, this is reasonable. But then "Frame num gap" should be of ERROR level too. H.264 standard states if there is a frame num gap, the decoder should infer an unintentional loss of pictures, assuming gaps_in_frame_num_value_allowed_flag = 0. But it is possible that FFmpeg encounters a frame loss but does not print any error messages, because the error concealment procedure (https://github.com/FFmpeg/FFmpeg/blob/n4.1.1/libavcodec/h264_slice.c#L1577) will clone the previous frame in place of the missing one. Also, regarding to the error concealment, why isn't `short_ref[0].field_poc` copied for cloned frames? The unset field_poc causes "co located POCs unavailable" error, despite `ref_list[1][0].poc` is valid when doing spatial direct predition. _______________________________________________ ffmpeg-devel mailing list ffmpeg-devel@ffmpeg.org https://ffmpeg.org/mailman/listinfo/ffmpeg-devel
