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I am using python to work on my project in image processing. Suppose I got a very large image ( 100000 x 100000), and I need to randomly select a 200 x 200 square from this large image. Are there any easy way to do this job? Please share some light with me. Thank you
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Sorry I don’t think it is 100000 x 100000, but the resolution of images are in 1 km and 2km. I am having trouble with selecting the area of 200 x 200.
If you convert to binary PPM format, then there should be an easy way to seek to the appropriate offsets – it’s not compressed, so there should be simple relationships.
So pick two random numbers between 0 and 100000-200-1, and go to town.
(I’m assuming you don’t have a system with 10’s of gigabytes of RAM)