Question

I was writing a program for capturing the screen at a set interval and when I started testing, I found that I get an OutOfMemoryException almost immediately after it starts capturing pictures. I tried allocating more memory – I gave it 256m, but that hardly helped. All that it did was make it last 2 or 3 more seconds before throwing the exception and crashing again.

I understand that the createScreenCapture(…) method uses a lot of memory, but I have seen example programs that can record for long amount of times using the same method – how do they do it?

Edit: I’ve used some of your guys’ advice and now I don’t get OutOfMemoryExceptions! Hooray! I took the route that involves saving the photos to the hard drive. However, actually writing them to an archive file does take quite a long time. Writing 63 frames into an archive file takes almost 2 minutes!

I can’t provide any code because I’m rewriting the I/O part. Working on improving the ^ situation.

Answer 1

I have seen example programs that can record for long amount of times using the same method – how do they do it?

Serialize the images to disk (as separate files or into a single Zip).

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Is there a certain procedure I should use for saving it on a hard drive? I was thinking of converting images into an int[] array and then just storing that, since arrays are serializable.

There are a number of strategies that can be pursued.

• Convert the image to a non-lossy (& easy to encode) image format and store the image either:
  1. In separate files on disk, or..
  2. As separate entries in an (uncompressed) Zip archive. By using a Zip we can get around early problems reported with storing ‘thousands’ of files. Make it uncompressed for considerations of speed (and the fact that Zip does very little for most media formats).
• I once saw code on usenet that was called (AFAIR) ‘Screenies’ or something like that (can’t find it now) that did much like you suggested. It stored the raw information (without any encoding) onto disk. I tried the code and could not get better performance for it than encoding the image to PNG & serializing the image to disk. You might want to run some tests to see which approach comes out faster now.