【单选题】Image compression is familiar to most users of computers in the form of image file extension,such as ________file extension is the lossy compression.
【单选题】_________ is the standard image file format in Windows operating system which uses bit map as storage format. In addition to optional image depth, it does not use any other compression.
【单选题】There is an image of 100 * 100 pixels, and the gray value of each pixel is represented in 8 bits. After Huffman coding, the image data is compressed to 40000 bits. The image compression ratio is ( ).