Howtosignalprocessing
- Why Discrete Cosine Transform DCT is widely used in image compression?
- Why was DCT chosen as transform domain for JPEG?
- What is 2d DCT in image processing?
Why Discrete Cosine Transform DCT is widely used in image compression?
Discrete Cosine Transform is used in lossy image compression because it has very strong energy compaction, i.e., its large amount of information is stored in very low frequency component of a signal and rest other frequency having very small data which can be stored by using very less number of bits (usually, at most 2 ...
Why was DCT chosen as transform domain for JPEG?
DCT has cosine function which is easier to compute and the number of coefficients become less. Thus, DCT can result more accurate image reconstruction even if the JPEG is lossy transformation. There is one step called quantization where less important pixels are discarded according to the frequency distribution.
What is 2d DCT in image processing?
The discrete cosine transform (DCT) represents an image as a sum of sinusoids of varying magnitudes and frequencies. The dct2 function computes the two-dimensional discrete cosine transform (DCT) of an image.
