Monday, 9 January 2017

RX480 h.264 problem update

ray_m
Hi, Engineering have analysed the ciip you provided and comeback saying "the corruption you see is because the clip itself is already corrupted, the first frame is a B-frame and it does not contain and SPS/PPS."  This of course is beyond my pay grade, but I found something odd. No matter what settings I use in MPCHC, the video is corrupted. If I play the same clip in VLC is plays fine. I've gone back responding that you also experience the corruption while watching the live TV broadcast. Is this correct ?
Frank Vella
Hi Ray, thanks for your response. I can confirm that when I enable LAV filter DXVA2 with H264 hw acc, the picture is corrupt when I watch it live, same applies when I use Microsoft decoder. This issue of no SPS/PPS in the media type was supposedly fixed by LAV support team in version 0.66.0
Also in my case that video I sent you plays fine in  MPCHC and DVBviewer when I disable h264 in LAV filter. 

LAV Filters 0.68.0 out - General DVBViewer Pro/GE...

If your engineers want to remote on to my PC let me know and I will try and help. Just as an additional note other users have uploaded videos for testing and it may be an idea to get another video from someone else just in case I have something wrong with my rig.

The question you need to ask is why does everything play fine with no HW acceleration h.264 and it goes wrong with DXVA2 turned on for h.264.



 what are SPS/PPS


Just spent about half an hour changing channels (all H.264 1080i) and noticed a variety of results. The data stream can vary from approx 3MBit/s to 10MBit/s ....most of the channels with very low bit rate the picture is very bad, the HD channels with higher bit rates fare a lot better and in some cases are ready for a minute or so before you notice a failure. This obviously throws a different perspective of the problem. The channels I was looking at in the UK ....BBC1 HD, ITV1 HD Channel 4 on Freeview, also tested on Freesat ....one channel NHK World HD the picture is totally frozen ( the sound is OK).


01-09_22-57-32_NHK World HD_NHK Newsline.ts - Goo... 

​The above video just recorded from NHK World HD the picture totally freezes when played live or recorded using H264 HW acc DXVA, when turned off it plays fine.  This was taken off fresat  (DVB-S2) so is different transmission type just in case it was DVB-T2 that was causing the issue.

btw Ray, when I play the first video I sent you on Friday in MPCHC with h.264 turned off in LAV it plays fine for me. Don't forget that if you use another decoder it may have H.264 HW acc turned on as default so may be initiating DXVA HW acceleration.