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Freddy
June 9, 2006, 16:29:54
Hello,
Is it possible to capture to buffer memory and saving later on (or discarding) to AVI file on HDD?

Thank you very much for your answer

Stefan Geissler
June 9, 2006, 16:58:49
Freddy,

Yes it is possible. If you lock a memory buffer, it will not be overwritten.
Saving single image buffer into an AVI file is a little bit more compilcated. If you want to do this, you must do the complete AVI stuff on your own.

The count of image buffers should not be so big. 500 image buffers is a lot, because each image buffer needs a lot of memory.

Please specify in more detail what you want to do.

Freddy
June 9, 2006, 18:19:04
I was thinking that maybe saving to HDD was a problem when trying to capture from two different cameras at the same time. I've seen a software that captures both cameras at the same time, but doesn't save to HDD until you stop the capture.
Maybe when capturing to buffer you are not collapsing the machine that much??
Maybe the problem is something else, but since i now know that capturing with 2 cameras is possible, i would like to try to do it.
Maybe VB6 (ActiveX) is too slow? I don't know what language is been used for this other software. Probably C.
I would appreciate any help about how to speed up my soft in order to capture from the two firewire cameras.

Thank you very much

Stefan Geissler
June 12, 2006, 09:04:09
Hello Freddy,

Capturing from two cameras should not be a problem. A simple way to check this is to use IC Capture. Also the IC ActiveX has no problems if two of them are used in one application.
You should have a look on the amount of data, that is to be saved to harddisc, but usually there is enough bandwidth available if the AVI files are compressed.

I can not imagine, that there is a software, that does not save the incoming frames into the AVI files while capturing. May be Windows shows a file size of 0 due to capturing, but this could be normal. If frames are saved in memory, then the physical memory of a computer would be fast at its end. Then Windows would start paging and this costs time.

Thus please check out IC Capture and capture two video streams. Use a fast codec like DivX.