On 11/14/2017 10:11 PM, Sasi Inguva wrote: > I don't know if the patch can be made more generic to work for all > demuxers, because this patch requires that PTS of all packets be available > in the header. The other route is to make it very specific to codecs with > B-frames.
All PTS may not be available in MP4 either, in the live profile fragmented MP4 case, no? I am not familiar enough with the fragmented MP4 demuxing code say whether we seek to each fragment and make it available or not. I assume you've tested such a case, or can (or know the fragment code)? It's feasible to restrict it to codecs, I suppose. >> You do not appear to be restricting this to one specific codec, or even >> codecs >> with B-frames. >> >> I can make it specific to only H264 / H265. The GOP structure should be applicable to most MPEG codecs, I think. > It is true that the patch will fail to compute the correct delay in lots of > cases. However the consequence of wrongly computing the has_b_frames is > pretty benign. It only increases the buffer size held for PTS reordering. > I can put a max-value check on the computed video_delay here. So in my > opinion, we won't see fatal regressions where a file is not able to be > decoded / played. It's true it's likely benign, but it's not exactly a "fix" either... From a user perspective, it's kinda possible to work around it "properly" (I use that term loosely here) by decoding enough frames to fill the max DPB for a given codec (e.g. 16 for H.264) in avformat_find_stream_info (or in a user's code if they don't use that function), isn't it? Though, I feel that particular fix won't be welcomed with open arms, due to a ~16x 'slow down' in probing. Does anyone else have an opinion™ on this? I guess it's "OK enough" if restricted by codec...? :V - Derek _______________________________________________ ffmpeg-devel mailing list ffmpeg-devel@ffmpeg.org http://ffmpeg.org/mailman/listinfo/ffmpeg-devel
