Patent ID: 7054370

Claim:
An apparatus for transcoding a video snap image comprising: a video decoder for performing a variable length decoding (VLD), inverse discrete cosine transform (IDCT), and inverse quantization with respect to an input video bit stream to display the decoded bit steam; a DC extraction section for extracting DC components from discrete cosine transform (DCT) coefficients of variable-length-decoded macro blocks; an adder for averaging the extracted DC components; a differential pulse code modulation (DPCM) section for obtaining and outputting a difference value between the DC component averaged by the adder or the DC component outputted from the DC extraction section and a DC component of a previous macro block, wherein the DPCM section obtains the difference value between the DC component of a color extracted by the DC extraction section and the DC component of a color of the previous macro block; a Huffman encoding section for Huffman-encoding the difference value outputted from the DPCM section; and a storage device for storing a Huffman-encoded snap image and the video bit stream as one signal train.