Library of JPEG images for decoder testing?

I'm writing an interface for a hardware JPEG decoder, and I'm looking for some test images.

Prior to hardware decompression, the software front-end must parse the JFIF and/or EXIF data to obtain the image dimension开发者_JS百科s and thumbnail. In testing, I found that my current version works well with images obtained from contemporary digital point-n-shoot cameras. In general, the parser obtains the dimensions from the SOF segment, and the thumbnail is retrieved from the EXIF data (if the thumbnail exists).

I'm looking for a broader range of test images to evaluate the system more exhaustively. For example, I have been unable to find any JPEG images that encode the thumbnail in a JFXX (i.e., second APP0) marker. Furthermore, I would like to test the code on a wide variety of images (sizes, progressive scans, etc.). This code is destined for a specialized consumer product, and images are expected to be obtained from a range of digital cameras, both old and new.

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