HuffmanTabellen

HuffmanTabellen, also known as Huffman Tables, are a fundamental component in the JPEG image compression standard. They are used to encode and decode the discrete cosine transform (DCT) coefficients of an image, which are then quantized and entropy-coded. Huffman Tables are named after David A. Huffman, who developed the Huffman coding algorithm in 1952.

There are two types of Huffman Tables used in JPEG: one for the luminance (Y) component and one for the chrominance (Cb and Cr) components. Each table consists of a set of codewords, which are variable-length binary codes assigned to the DCT coefficients based on their frequency of occurrence. The more frequent coefficients are assigned shorter codes, while the less frequent ones are assigned longer codes.

The Huffman Tables are generated during the encoding process by analyzing the frequency of each DCT coefficient in the image. This analysis is used to create a probability distribution, which is then used to generate the optimal set of codewords for that image. The resulting Huffman Tables are stored in the JPEG file header and are used during the decoding process to reconstruct the image.

Huffman Tables play a crucial role in the JPEG compression standard, as they allow for efficient encoding and decoding of the DCT coefficients, which are then used to reconstruct the image. The use of variable-length codes in the Huffman Tables helps to reduce the overall file size, while still maintaining a high level of image quality.