Very long checking AviSynth script

[kibi]

There is an issue at checking AviSynt stage while processing external AVS video file as video source.

I made a simple workflow like this:
In Folder - A/V Media - Compress MP4 - Out Folder

In-folder monitors for *.AVS files. A/V Media makes full decompress, MP4 packs in x264 format to Output folder.
My source AVS files have structure like this (it glues together several files):

src1 = FFmpegSource2("R:\To_VOD\Test\SubFolder\VODGRF000001.mp4",cachefile = "C:\FFAStrans\Test-zone\Temp\rundown-697\VODGRF000001.mp4.ffindex",atrack=-1).AssumeFPS("pal_video")
src2 = FFmpegSource2("R:\To_VOD\Test\SubFolder\VODGRF000002.mp4",cachefile = "C:\FFAStrans\Test-zone\Temp\rundown-697\VODGRF000002.mp4.ffindex",atrack=-1).AssumeFPS("pal_video")
src3 = FFmpegSource2("R:\To_VOD\Test\SubFolder\VODGRF000004.mp4",cachefile = "C:\FFAStrans\Test-zone\Temp\rundown-697\VODGRF000004.mp4.ffindex",atrack=-1).AssumeFPS("pal_video")
dest = src1 + src2 + src3
return dest

It's fully working when is opened, for example in AVSPMOD, so it's not an issue of the system AviSynth installation. More over, FFASTrans makes resulting video, but stage of checking script takes all the TTL. Temporary ~AVS could be also successfully played in an external viewer (AVSPMOD).

The issue was reproduced at 0.6.5 and 0.7.0 versions.

[admin]

What happens if you skip the "A/V Media"-decoder?: In Folder - Compress MP4 - Out Folder

-steipal

[kibi]

Wow! Works like charm.
Please tell, why sometimes it's necessary to use A/V Media decoder and sometimes not?
Thank's a lot.

[admin]

Great!
The "A/V Media"-decoder does two things:

1. It makes you media ready for the filters. If you want to use filters then you MUST decode. Decoding actually creates a AviSynth-script from your file. All filter-nodes are based on AviSynth.

2. It tries to create proper intermediates of your media in case of any known anomalies during the initial media checking, so that "bad" media is conformed to "good" media. It sometimes helps encoding. This is especially important when using the "Custom FFmpeg"-encoder because it cannot adapt to the initial source like the built in encoders does. So decoding makes sure you ALWAYS have ONE video stream and ONE audio stream with 32 audio-channels.

-steipal