Image Compression Using Discrete Cosine Transform & Discrete Wavelet Transform
نویسنده
چکیده
Image compression plays a vital role in digital image processing. The need for image compression becomes apparent when number of bits per image are computed resulting from typical sampling rates and. quantization methods. For example, the amount of storage required for given images is (i) a low resolution, TV quality, color video image which has 512 x 512 pixels/color,8 bits/pixel, and 3 colors approximately consists of 6 x 106 bits;(ii) a 24 x 36 mm negative photograph scanned at 12 x 10−6mm:3000 x 2000 pixels/color, 8 bits/pixel, and 3 colors nearly contains 144 x 106 bits; (3) a 14 x 17 inch radiograph scanned at 70 x 10−6mm: 5000 x 6000 pixels, 12 bits/pixel nearly contains 360 x 106 bits. Thus storage of even a few images could cause a problem.DCT is one of the transforms used for lossy image compression. This paper reveals a study of the mathematical equations of the DCT and its uses with image compression.
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