ISO/IEC – Information technology – Generic coding of moving pictures and associated audio information – Part 2: Video. Amendment 2 to International Standard ISO/IEC was prepared by. Joint Technical Committee ISO/IEC JTC 1, Information technology, Sub-. ISO/IEC. Third edition. Information technology — Generic coding of moving pictures and associated audio information —. Part 2: Video.
|Published (Last):||15 March 2005|
|PDF File Size:||13.92 Mb|
|ePub File Size:||20.50 Mb|
|Price:||Free* [*Free Regsitration Required]|
Video based on H. The penalty of this step is the loss of some subtle distinctions in brightness and color.
H.262/MPEG-2 Part 2
Sometimes no suitable match is found. Digital Item Part 5: See Compression methods for methods and Compression software for codecs. MPEG-2 supports all three sampling types, although 4: All articles beginning with “ITU”.
Each picture element a pixel is then represented by one luma number and two chroma numbers. Then, for each of those macroblocks, the reconstructed reference frame is searched to find that 16 by 16 macroblock that best matches the macroblock being compressed. The tables below summarizes the limitations of each profile and level, though there are constraints not listed here.
H/MPEG-2 Part 2 – Wikipedia
Reference Software Part 5: Thus, each digitized picture is initially represented by three rectangular arrays of numbers. In it was extended by two amendments to include the Registration of Copyright Identifiers and the 4: These describe the brightness and the color of the pixel see YCbCr. Open Font Format Part A Iao stream may be recreated losslessly only if extended references are not used. But, if something in the picture is moving, the offset might be something like 23 pixels to the right and 4 pixels up.
High Efficiency Video Coding Part 3: Next, the quantized coefficient matrix is itself compressed. A profile defines sets of features such as B-pictures, 3D video, chroma format, etc. Streaming text format Part Briefly, the raw frame is divided into 8 pixel by 8 pixel blocks.
For example, the sky can be blue across the top of a picture and that blue sky can persist for frame after frame. Advanced Video Coding H. While the above generally describes MPEG-2 video compression, there are many details that are not discussed including details involving fields, chrominance formats, responses to scene changes, special codes that label the parts of the bitstream, and other pieces of information.
By starting in the opposite corner of the matrix, then zigzagging through the matrix to combine the coefficients into a string, then substituting run-length codes for consecutive zeros in that string, and then applying Huffman coding to that result, one reduces the matrix to a smaller array of numbers.
Retrieved 13 August If the video is not interlaced, then it is called progressive video and each picture is a frame. Video compression is practical because the data in pictures is often redundant in space and time. This works because the human visual system better resolves details of brightness than details in the hue and saturation of colors.
This page was last edited on 20 138188-2at The frame being compressed is 13818- into 16 pixel by 16 pixel macroblocks. Information technology – Generic coding of moving pictures and associated audio information: Scene description Part If one applies the inverse transform to the matrix after it is 31818-2, one gets an image that looks very similar to the original image but that is not quite as nuanced. Retrieved 24 July To generate a P-frame, the previous reference frame is reconstructed, just as it would be in a TV receiver or DVD player.