On Thu, Jun 14, 2012 at 9:51 PM, Sujoy Roy <[email protected]> wrote: > I have uploaded the "specific" video using ftp. The filename is > beating_bars.ogv. While debugging through producer_avformat.c, i checked the > value of pkt.dts after av_read_frame being called in producer_get_image. And > found that its value is jumping from 0, 1 to directly to 169. And if i press > shift+h, then it goes back to the begining and plays perfectly ok, and value > of pkt.dts increases smoothly from 0,1,2,3, ... > After digging through this phenomena of shift+h, i found that when i am > pressing shft+h, it is calling reopen_video.
There is something that is preventing libavformat from properly seeking within the first 20% or so of this file. When I play it in avplay and seek in the 5% to 20% range, then it too pauses for a while until time "catches up" to the stream. So, even if it were possible to overcome the problem playing from the beginning, if you set an in point somewhere before 169, then it will have a problem. If I force the clip to be non-seekable within producer_avformat.c:get_basic_info() then it does play fine, and that looks to be the only real workaround. The test for seek-ability passes on this clip, but it is not desirable to make the test more stringent. Usually, there are more false negatives than false positives. I could add a force_seekable property to the consumer so people can choose to workaround faulty clips for simple, sequential playback or transcode scenarios. > - Sujoy > > > On Fri, Jun 15, 2012 at 6:09 AM, Dan Dennedy <[email protected]> wrote: >> >> On Tue, Jun 12, 2012 at 11:36 AM, Sujoy Roy <[email protected]> wrote: >> > When i play a "specific" Theora video using melt, it freezes (sort of) >> > the >> > melt-screen upto first 190 frames, then it moves as expected. But it >> > plays >> > smoothly in ffmpeg or totem player, no freezing; i am on Fedora 16. I >> > have >> > downloaded the source code of melt. But there is no text containing >> > "theora" in those files. I guess the video decoding is being handled by >> > libavformat. Any tip about where to dive-in to find the cause of the >> > video >> > freezing? >> >> See src/modules/avformat/producer_avformat.c >> >> I am in the middle of a complete overhaul of the seek and sync in that >> piece of code. Likely your file will be affected as well as possibly >> any fix you come up with. If you upload it via anonymous ftp to >> dennedy.org, then I will take a look at it in the midst of checking my >> code changes. >> >> -- >> +-DRD-+ > > > > ------------------------------------------------------------------------------ > Live Security Virtual Conference > Exclusive live event will cover all the ways today's security and > threat landscape has changed and how IT managers can respond. Discussions > will include endpoint security, mobile security and the latest in malware > threats. http://www.accelacomm.com/jaw/sfrnl04242012/114/50122263/ > _______________________________________________ > Mlt-devel mailing list > [email protected] > https://lists.sourceforge.net/lists/listinfo/mlt-devel > -- +-DRD-+ ------------------------------------------------------------------------------ Live Security Virtual Conference Exclusive live event will cover all the ways today's security and threat landscape has changed and how IT managers can respond. Discussions will include endpoint security, mobile security and the latest in malware threats. http://www.accelacomm.com/jaw/sfrnl04242012/114/50122263/ _______________________________________________ Mlt-devel mailing list [email protected] https://lists.sourceforge.net/lists/listinfo/mlt-devel
