I want to know what size should be the image to use it as a hashset/dictionary key. I’m also thinking about using hash functions for this purpose but i’m afraid of hash collisions. I need to store about million of images.
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I want to know what size should be the image to use it as a hashset/dictionary key. I’m also thinking about using hash functions for this purpose but i’m afraid of hash collisions. I need to store about million of images.
A bitmap image as a key? That’s not a very good idea. Hashset keys should be as small as possible, otherwise performance will suffer significantly.
What you can do is calculate a hash value (say a SHA1) from the image, and then use that as the key. It’s only 20 bytes so that should be a good size, much better than a full bitmap image anyway.