avisynth slow to load using FFVideoSource(....) than Virtualdub

[marcorocchini]

Hi cats

FFVideoSource(input.mxf)

I noted that avisynth (with installed the ffms2.dll plugin) to load an audiovideo .mxf of 45GB employs several minutes, meanwhile virtualdub (with the ffmpeg plugin) employs few seconds: why this?

In avisynth I have try use

FFvideoSource(input.mxf, seekmode=-1)

or seekmode=2 / 0 and others option about indexing but avisynth appear alwais slow lo to load video files. I have also try to change ffmp2.dll but nothing changes, it's alwais slow to open

Is there a remedy?

[Detmek]

Ffvideosource() needs to index video before opening it, ffmpeg plugin for VD does not index video.

[marcorocchini]

I use avisynth not for frameserve editing NLE or other similar application, I use it only to transcode from .mxf files into .avi mjpeg files so I wonder: there is a way to tell FFVideoSource to don't index video? Simply I don't like waiting 5-6 minutes each time I have a large .mxf file.

Why FFVideoSource have to indexing? or if not possible avoid indexing is there a way to reduce time for indexing?

[hello_hello]

I've barely used it myself (I tend to use ffms2 out of habit and because it has frame rate conversion options), but L-Smash has a non-indexing mode.

LWLibavVideoSource("D:\video.mkv")
http://forum.doom9.org/showthread.php?t=167435

I don't know much about it.... the types of video it'll open or whether indexing is generally the better method etc. Maybe someone else does.

[ndjamena]

Pre-indexing? That's the only way DGIndex/MPEG2Source works. You could try indexing the next file using ffmsindex.exe while encoding the current file...

[hello_hello]

Is DirectShowSource an option? It's generally not recommended as it's not frame accurate when seeking, but if you're just transcoding a whole file from start to finish it should be fine. No indexing required.

[hello_hello]

It appears I was wrong about LWLibavVideoSource not creating an index file (I discovered after reading some more of the thread I linked to and trying it myself). It seems it still indexes the video, but just keeps the index in RAM when "cache=false" is set. Which seems to be even worse..... because it needs to index every time a file is re-opened.

[Detmek]

Avisource(), Directshowsource() and dss2() (needs haali matroska splitter installed) are the only source options for avisynth that do not use indexing. If you don't seek or split file you can use these options.

[marcorocchini]

https://www.dropbox.com/s/ioy79qrqvfo0pss/C0020.mxf?dl=0

I need to load files type like this: mxf

but I also have .mxf of 45-50 GB and with this files avisynth (ffms2) employs also 12-15 minutes only for indexing

Can I use virtualdub to "frameserve" avisynth?

[Detmek]

You can but I still think it is easier to use directshowsource() or dss2().

I tried to use VD with some filters to frameservere video to MeGUI but sometimes VD would stack in the middle of encoding process.

[marcorocchini]

use directshow exposed to risks and problems of reliability... yes it could work but I think is not the correct way

but, also to understand, if I want pass trough virtualdub how I have to this in avisynt?

[marcorocchini]

can I batch frameserve virtualdub?

[marcorocchini]

I open virtualdub and load C00121.mxf (using the ffmpeg plugin)
alwais in virtualdub, I do: "start frameserver" and save c:\cat.vdr

frameserving active (I leave open that window)



in avisynth I do:

AviSource("c:\cat.vdr")

all ok, but now I have to batch automate the procedure.

I wonder: can I create with a batch automatically a .vdr file?

and Overall: is there a way to don't keep virtualdub alwais in "frameserver" active mode? Or else: is there a way to use the .vdr files so that virtualdub
is invoked only if necessary, by avisynth? because if I close the "frameserver mode" windows (after saved the cat.vdr file) ---> avisynth cannot load nothing

[hello_hello]

use directshow exposed to risks and problems of reliability...

As opposed to trying to frameserve with VirtualDub??

yes it could work but I think is not the correct way

What's the basis for your thoughts there? Why is it not "correct"?

DirectShow isn't frame accurate when it comes to seeking, but for decoding a video from start to finish it's fine. In fact DirectShow will sometimes work when other methods of decoding (ie ffms2 etc) won't.
Sometimes more complex Avisynth filtering can cause issues with DirectShow, in which case I'd decode via DirectShow to an intermediate lossless file first, then apply the filtering while re-encoding the lossless file, but for standard decoding and re-encoding from beginning to end, DirectShow is normally fine. I've re-encoded many to hundreds of videos via DirectShow in the past.

[marcorocchini]

with the direcshow I'm afraid that everything is at the mercy of too many uncontrolled variables. Plugins internally installed at least avoid certain problems

[hello_hello]

with the direcshow I'm afraid that everything is at the mercy of too many uncontrolled variables.

As opposed to trying to frameserve with VirtualDub??

Plugins internally installed at least avoid certain problems

Which ones?