JPEG Compression Algorithm
JPEG Compression Algorithm
This Demonstration shows how a two-dimensional discrete cosine transform works on the image blocks during JPEG compression and how the data is degraded by the quantization matrix. Red points in the graphs on the right side display zeros, which are important for the file size reduction. More zeros give more size reduction but worse image quality. You can choose photos and images with patterns; most of them are difficult to compress by the JPEG algorithm.