last played few second added at start of video at encoding time

[anonyme-x22]

Hello,

I use virtualdub 64bit + x265 encoding + avisynth.
When opening the file with virtualdub i have no issue.
When opening the avs, if i play the video in virtual dub or seek somewhere, when i start the encoding process the last position few frame are
added to the start of the video after encoding.
You see it by virtualdub preview.
Seeking to something black or just open encode without seeking help, but there is audio is always unsync.

Can help?

Here is the script:
Video=Avisource("F:\test.avi")
TextSub(Video, "F:\test.srt")

Video is x265+ac3, just two stream.

Ps: It's avisynth+
Thanks in advance,
Have a good day,
Rgds,

[hello_hello]

Try something other than Avisource.

http://avisynth.nl/index.php/LSMASHSource
To open just the video
LWLibavVideoSource("F:\test.avi")
or to open video and audio
V = LWLibavVideoSource("F:\test.avi")
A = LWLibavAudioSource("F:\test.avi")
AudioDub(V, A)

http://avisynth.nl/index.php/FFmpegSource
latest version
https://github.com/FFMS/ffms2/
To open just the video
FFVideoSource("F:\test.avi")
or to open video and audio
FFmpegSource2("F:\test.avi", atrack=-1)

The first time you open a file with one of the above source filters it'll be indexed so it might seem a bit slow. After that it'll be quite fast as long as you don't delete the index file. If either have a problem with your AVI, try remuxing it as an MKV with MKVToolNix first, then open the MKV instead.

This one's apparently very reliable, but also very slow to index files.
https://github.com/vapoursynth/bestsource

[anonyme-x22]

thanks i will try, ffmpegsource2 to see if better.
i prefer avi to mkv, much more compatible and don't require system muxer/demuxer add-on.
I think the issue is related to virtual audio/video buffer, which isn't reset when using avisynth script...
I have set them to max (256Mo), perhaps will also try default settings...
Also it is possible that the script use avisynth+ 32bit into vdub 64 causing this issue.
by the way if some know a correct (like vobsub with gui for font format) vdub64 subtitle plugin that would definitively be better...

[jagabo]

Your source video has some leading B-frames that cannot be decoded (the file was presumably trimmed from a longer open GOP source). Some source filters return the first I-frame in place of the bad B-frames. Some just start with the I frame. Some return whatever junk is in the frame buffer (so if you seek forward, then back to the start, you'll get that later frame).

Try LSMASH in addition to ffmpeg source filters.

Also, one shouldn't use AVI for inter-frame codecs like x265. Especially with open GOPs.