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Image Sequence Processing

Posted: 2012-01-11T14:49:55-07:00
by wwwebsurfer
I'm working on generating short videos from still images (kind of a powerpoint to video equivalent converter.)

It's working nicely, but it's just dog dirt slow. By the time you generate 30 frames for a second of video and you try to feed in 50 slides at 10 seconds each it takes a long time to process.

My question is can I load in the video background photo and the slide photo into memory and the output a large sequence of images from it without processing them all multiple times loading them in and out of memory thousands of times (in my current process the slides are being slowly animated and dissolve transitions are being inserted - it's not as simple as using the copy command instead.) So for instance if I can load image A and image B into memory and then composite them hundreds of times while changing the -geometry values to simulate animation.

Currently I'm using a simple bash script on Ubuntu Server; but I'm open to switching to C-based languages if there's a significant performance advantage.

Thanks!

Re: Image Sequence Processing

Posted: 2012-01-11T15:31:25-07:00
by fmw42
What you want is something that I have asked about before, but I don't think it is in the cards. Possibly with IM 7 (underdevelopment). The IM developers can elaborate or correct me if I am wrong.

However in IM 6, you can copy images to memory (.mpr) format, but they go away after each command line. So you would have to prepare a very long command line with parenthesis and write statements, one for each composite. You won't be able to do a loop with a new command line in each iteration.

see
http://www.imagemagick.org/Usage/files/#mpr
http://www.imagemagick.org/Usage/basics/#parenthesis
http://www.imagemagick.org/Usage/files/#write