Thread: GetImage slowing down image processing.
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Unread 12-02-2010, 18:42
Greg McKaskle Greg McKaskle is offline
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Re: GetImage slowing down image processing.
What are the settings for the camera? You mention setting FPS, but have other settings changed? In particular, setting the compression very low can cause the camera to be quite late. Try setting the image size to medium and the compression to 20%.

If this helps, the issue seems to be with large(>16kB) allocation of memory on vxWorks to hold the compressed image. By setting the medium image compression to 20%, I was able to get much higher frame rate. I suspect that this may be causing the glitches you are seeing. Memory managers tend to have internal allocation thresholds that determine which pool of memory an allocation comes from. There can be odd timing differences when crossing these thresholds and different timing differences when reallocating blocks of memory from these different heaps. I haven't had a chance to find a workaround except to keep the image sizes in the fast range.

Greg McKaskle