From henjin.iamtheweirdo on February 04, 2012 21:11:51

I think the cause of this issue is r518 . I know that commit meant to prevent crash when decoder returns an empty frame. However, I get that error message very often when I open my own encoded MP4s with FFMS2 and seek through them (even when I let x264 output as RAW AVC then mux the result to MP4 by L-SMASH muxer, that error still occurred). In fact, if I revert that commit for my own build or remux those MP4s to MKVs, I can seek them without any problems (with threads>1, of course).

From SAPikachu on February 05, 2012 02:24:53

SAPikachu/ffms2_hacks@5651d56 I also encountered this problem. Just made this workaround patch on my private build and seems the problem disappeared. (Sorry for the incorrect white spaces, I didn't notice that before pushing, fixed them in another commit)

From kalle.blomster on February 06, 2012 02:01:04

I downloaded a random animu fagsub in mp4, loaded it in VirtualDub and clicked around a lot with threads=8 without managing to reproduce the issue. Please provide a sample that shows this behavior reliably.

From kalle.blomster on February 06, 2012 02:02:21

Also, if commenting out the check seems to solve the problem there's some really bizarre threading magic going on, because otherwise FFMS2 WILL crash with a null pointer dereference.

From kalle.blomster on February 06, 2012 02:30:59

Never mind the sample, I loaded the wrong file, hurpa durpa durp. I can reproduce it now.

From arslanoglou.georgios on February 06, 2012 02:38:26

Latest Kyuubi release for Fairy Tail is one example.
If you were so lucky and didn't get it with seeking, you can start a simple encode and you will see it.

From 4Selur on February 12, 2012 06:33:19

ran into the same problem with a mov(avc,pcm) file: http://www.mediafire.com/?80iz1u6ezjx75rh FFVideoSource("d:\canon_powershot_sx1_is_02_aliasing.mov",cachefile="D:\Encoding Temp\canon_powershot_sx1_is_02_aliasing_41.ffindex")
causes artefact
FFVideoSource("d:\canon_powershot_sx1_is_02_aliasing.mov",cachefile="D:\Encoding Temp\canon_powershot_sx1_is_02_aliasing_41.ffindex", threads=1)
works fine

using: Avisynth 32bit 2.6 and the latest ffmpegsource from Jan 25

From arslanoglou.georgios on February 12, 2012 06:35:44

Well, doesn't sound too weird, since if I am correct, mov is essentially a hacked mp4 container. You may try to rename your file to mp4 and play it. Most of the times, it works, and the video plays smoother than when in mov, since the mp4 decoders are much better than the mov ones...

From 4Selur on February 12, 2012 06:59:30

You may try to rename your file to mp4 and play it.
-> tried, does not help

From arslanoglou.georgios on February 12, 2012 07:03:05

I didn't mean it will help you with the issue here. It was just a comment in general.
But if renaming it to mp4 allows you to play it with a video player, then you can try to remux the renamed mp4 to mkv via mkvtoolnix.
The remuxed mkv should work correctly with ffms2 and threads>1 ;)

From 4Selur on February 12, 2012 07:15:12

The remuxed mkv should work correctly with ffms2 and threads>1 ;)
it does not, as soon as ",threads=1" is missing I get artifacts, see: http://www.mediahump.com/gallery/4005/

From 4Selur on February 12, 2012 07:21:01

side-note: ffplay, mplayer, mpc-hc all have no problem during playback

From martin.hamant on June 16, 2012 03:45:35

Same problem here with FFmpegSource2 2.17 / seeking in a H264 AVC video.
Avisynth 2.5 32 bits.
Win7 x64

From arslanoglou.georgios on June 16, 2012 05:59:54

2.17 is r637 or r640 . This should be fixed with r691 , but it a compiled build is not yet available.

From tgoyne on June 20, 2012 19:01:10

Status: Fixed