Strange x264 problem

[raziel666]

I'm relatively new on x264, but haven't found this problem anywhere else, so I decided to post.
I noticed that on some videos I have that begin with fade-ins and/or end with fade-outs, the x264 compresses them, I get the same number of frames and fps, but some frames of the fade are missing from the final video. I've tried several x264 configs (even the default) but I got nothing. I tried to compress the same videos with xvid and it worked just fine. Does anyone have some idea about this? Thanks a lot.

[W3ird_N3rd]

Just checking: how do you check for the missing frames?

If you do so by playback, check your CPU load. Maybe your CPU just can't keep up and skips some frames. You could try encoding at a lower resolution.

Do fades in the middle of a video work fine?

If you go through the frames, are there double frames in the fades?

[raziel666]

The thing is that these videos are parts of a bigger video and when I try to join them I get the exact problem. For the missing frames I also view each frame with virtualdub and see the differences there as well.

[GodofaGap]

If you use b-frames with VFW the last few frames inevitably get dropped, due to encoding lag. This is only avoidable by not using VFW, or not using b-frames.

[Caroliano]

:search:

The same problem, the causes and the solution: http://forum.doom9.org/showthread.php?t=111704

[raziel666]

This problem does not appear only in VFW mode (apparently virtualdubmod i'm using) but also using MeGUI. I don't know if the disabling of b-frames will solve this, I will try it and will see what happens.

[huang_ch]

I'm also experience a frame drop problem, though the frame number of the final video is almost the same, but it really cause about de-async in video/audio for about 2 sec at the last, and I've at least found one scene that the encoded video droped about 30 frames, it is a pretty staticaly scene. Is there any suggestion on how to find the root cause? or any suggestion on which options to try?
And I've tried to only encode a small period which contains that scene(about 10~20 sec), the problem doesn't exist. But when I encode the whole video (it is an Anime for about 24 min long), the problem appears. I'm now trying for a second time. And I'm using MeGUI, no VirtualDub

[Sharktooth]

what x264 revision and build are you using?

[huang_ch]

I've to say sorry, because I've found that my problem is not X264, but FFDSHOW+AVISYNTH.
My source is a XVID+AC3 packed MKV, and I use latest FFDSHOW (2006/05/26 from free-codecs.com), and set to use libavcodec to decode the XVID videos.
The version of AVISynth is 2.5.6, and my script is pretty simple, first line is a directshowsource and next is convert to YV12.
And when I tried to play this AVS in MPC, I can also found the frame drop, but when I install XVID 1.1/1.2 and make it the default decoder of XVID, everything is all right.
But if I directly play that MKV with FFDSHOW in MPC, no frame drop happens.

Any ideas?

[MeteorRain]

try demux xvid into avi, and use avisource() instead.