JPEG Image Compression Algorithm

The JPEG image compression algorithm is a widely-used method for image compression. This algorithm first performs an 8x8 Discrete Cosine Transform (DCT) to convert spatial domain image information into frequency domain coefficients. The implementation typically involves dividing the image into 8x8 pixel blocks and applying DCT transformation to each block using mathematical operations that separate high-frequency and low-frequency components. Next, the algorithm quantizes the frequency domain coefficients using predefined quantization tables, which reduces data precision by dividing DCT coefficients by corresponding quantization values and rounding the results - this step achieves significant compression by eliminating less perceptually important high-frequency information. Finally, the quantized data undergoes Huffman encoding, where variable-length codes are assigned based on symbol frequency to minimize overall data size, completing the compression process with efficient entropy coding.