As promised, here are the specifics of the stuttering problem I mentioned yesterday. I've seen this weird stuttering sporadically on streamed video ever since I started running the Gotham beta's on the Pi (I checked back and reproduced it on March 23 but didn't verify any earlier) - and I suspect it occurs with videos with "glitches" in them that are perhaps poorly edited together or have some corrupted/missing frames, but this is the first time I've found one of my own local files to have the problem so that I can easily reproduce it.
First, here's two examples of what it looks like: (I didn't upload them to youtube as they'll probably get blocked for copyright reasons even though short clips should be "fair use"...also I didn't want youtube doing any processing or frame rate conversion on them. Download for best video quality)
https://www.dropbox.com/s/ixnz1tsyjrqycay/IMG_0665.MOV
https://www.dropbox.com/s/13563by7df84lh3/IMG_0666.MOV
On this particular video the symptoms are triggered by large forward jumps (10 minutes) and the first and second large jump from the beginning of the file will reproduce it. The above videos are shortly after two jumps forwards.
If I use many small (30 second) jumps from the beginning of the video to same point in the video, it plays fine. Here is an example of the second section of video reached via lots of small jumps instead of two large ones, and it can be seen playback is perfect:
https://www.dropbox.com/s/pq3gnchz3h4r06h/IMG_0667.MOV
Also if I skip further into the video playback synchronises properly and I can then skip back to the same place and playback is perfect. Here is a debug log taken during playback. It's a fairly clean .xbmc folder to minimise any outside influences. In the debug log I started playback of the video then skipped +10 minutes twice then let it play for a little while while it was stuttering:
http://pastebin.com/0Lc3kVe7
Here's a mediainfo on the file:
Code:
* * * MediaInfo Mac 0.7.36.0 file analysis report.
* * * MediaInfo Mac is ©2010 by Diego Massanti - http://mediainfo.massanti.com
* * * MediaInfoLib by Jerome Martinez - http://mediainfo.sourceforge.net
Created on: 29 Mar 2014 16:47:12 GMT
Report for file: 2001 A Space Odyssey (1968).mp4
General / Container Stream #1
Total Video Streams for this File.................1
Total Audio Streams for this File.................1
Video Codecs Used.................................AVC
Audio Codecs Used.................................AAC LC-SBR
File Format.......................................MPEG-4
Play Time.........................................2h 28mn
Total File Size...................................854 MiB
Total Stream BitRate..............................802 Kbps
Video Stream #1
Codec (Human Name)................................AVC
Codec (FourCC)....................................avc1
Codec [email protected]
Frame Width.......................................1 280 pixels
Frame Height......................................576 pixels
Frame Rate........................................23.976 fps
Total Frames......................................214145
Display Aspect Ratio..............................2.222
Scan Type.........................................Progressive
Color Space.......................................YUV
Codec Settings (Summary)..........................CABAC / 5 Ref Frames
QF (like Gordian Knot)............................0.042
Codec Settings (CABAC)............................Yes
Codec Settings (Reference Frames).................5
Video Stream Length...............................2h 28mn 51s 631ms
Video Stream BitRate..............................735 Kbps
Video Stream BitRate Mode.........................VBR
Bit Depth.........................................8 bits
Video Stream Size.................................782 MiB (92%)
Video Encoder.....................................x264 - core 116 r2074 2641b9e
Video Encoder (Settings)..........................cabac=1 / ref=5 / deblock=1:-2:-1 / analyse=0x3:0x113 / me=umh / subme=8 / psy=1 / psy_rd=1.00:0.00 / mixed_ref=1 / me_range=16 / chroma_me=1 / trellis=1 / 8x8dct=1 / cqm=0 / deadzone=21,11 / fast_pskip=1 / chroma_qp_offset=-2 / threads=12 / sliced_threads=0 / nr=0 / decimate=1 / interlaced=0 / bluray_compat=0 / constrained_intra=0 / bframes=3 / b_pyramid=2 / b_adapt=2 / b_bias=0 / direct=3 / weightb=1 / open_gop=0 / weightp=2 / keyint=250 / keyint_min=23 / scenecut=40 / intra_refresh=0 / rc_lookahead=50 / rc=2pass / mbtree=1 / bitrate=735 / ratetol=1.0 / qcomp=0.60 / qpmin=10 / qpmax=51 / qpstep=4 / cplxblur=20.0 / qblur=0.5 / ip_ratio=1.40 / aq=1:1.00
Date of Original Encoding.........................UTC 2011-12-26 13:47:23
Audio Stream #1
Codec.............................................AAC
Codec (FourCC)....................................40
Audio Stream Length...............................2h 28mn 51s 755ms
Audio Stream BitRate..............................64.0 Kbps
Audio Stream BitRate Mode.........................VBR
Number of Audio Channels..........................2
Audio Channel's Positions.........................Front: L R
Sampling Rate.....................................48.0 KHz
Audio Stream Size.................................68.1 MiB (8%)
Date of Original Encoding.........................UTC 2011-12-26 13:47:43
Some further observations - it's not related to display refresh rate, I've tried 24, 50, and 60Hz and with adjust refresh rate to match on and off. It doesn't happen if I switch back to the stable version of Frodo that comes with Raspbmc. It doesn't happen on Gotham Beta 2 on my Mac. The same problem happens on both an HDMI TV and a DVI PC monitor. It doesn't matter where the file is played from - in the above example it was playing directly from SD card. A random sampling of my movie collection didn't show any other files exhibiting the same problem.