Tips on doing a wall of 16 videos?

[wrybread]

I'm using AVISynth to make a grids of videos, going from 1 video to 4 videos to 9 videos to 16 videos. I'm using VirtualDub to render the videos, so they don't have to play well in real time.

My source media is H264, avc1, 640x480, 60fps, with sound. I'm wondering what the best way to import those clips is? Importing as DirectShowSource works well until I reach 16 clips, and then VirtualDub runs out of memory and can't finish rendering. Using FFmpegSource2 works, but it seems much slower than DirectShowSource, and the resulting files seem corrupt (won't play in VLC, though they will in Zoom Player).

Anyway, before banging my head against this wall much longer I thought I'd see if anyone has any optimization tips for working with H264 sources.

[poisondeathray]

What is your exact script? maybe there are more efficient methods, or fewer calls you can make to reduce memory consumption

Have you tried SetMemoryMax() for the memory issue? e.g. SetMemoryMax(1024)

Have you tried FFMS-MT ? the multithreaded branch instead of vanilla ?

[pbristow]

You could try doing the job in several passes, i.e. pre-render four sets of 2x2 (save them in a high bit-rate, low compute-requirement format, ideally something lossless like lagarith), then run the results through the same script again to get your final 4x4 result...?