.png) is a lossless image-compression codec. Its RBG color palette is, however, increased from 24 bits to 32 bits and 48 bits. One of the interesting features of PNG is object transparency (also available to some more limited extent in GIF), i.e., the possibility of making certain image objects appear translucent over their background, as achieved through a supplementary "alpha" channel. The core PNG compression algorithm is based on the license-free DEFLATE which, as we have seen earlier, combines LZ77 and See, for instance: http://en.wikipedia.org/wiki/JPEG_2000. See also, the JPEG-2000 official website: www.jpeg.org/jpeg2000/. 34 See, for instance: http://en.wikipedia.org/wiki/Wavelet; http://en.wikipedia.org/wiki/Discrete_wavele transform. 35 See, for instance: http://en.wikipedia.org/wiki/GIF. 36 See, for instance: http://en.wikipedia.org/wiki/Portable_Network_Graphics. Overview of data compression standards Huffman coding. Under its MNG extension, PNG also supports graphic animation, although it is more complex and not widely supported on the Internet. Two other image formats are TIFF (tagged image file format)³8 and BMP (short for bitmap)³. In short, TIFF (filename extension .tiff) was originally designed as a common standard for image scanners; with a 32-bit uncompressed format albeit with the option of lossless LZW (Lempel-Ziv-Welch) compression. Its specificity, hence, its name, is the capability of handling multiple images and data in a single file with as many header "tags." The format BMP (filename extensions .bmp or .dib) offers a variety of coloring depths (1, 2, 4, 8, 16, or 32 bits) with an uncompressed image format. Owing to their redundancy, BMP files lend themselves to efficient lossless compression, for instance through ZIP (see above). Video The most generic standard to encode video data is known as MPEG (short for motion pictures expert group), 40 more accurately defined under MPEG-1, MPEG-2, and MPEG-4. It is beyond the scope of this overview to approach such standards in the appropriate l