$8 \times 8$ block matrix in JPEG image compression?

1. Why we need to divide images into 8 8 blocks in JPEG encoding scheme?
2. What is the standard size of block in JPEG compression?
3. Does JPEG use overlapping DCT blocks?

Why we need to divide images into 8 8 blocks in JPEG encoding scheme?

Any matrices of sizes less than 8 X 8 dont have enough information to continue along with the pipeline. It results in bad quality of the compressed image.

What is the standard size of block in JPEG compression?

The image is split into blocks of 8×8 pixels, and for each block, each of the Y, C_B, and C_R data undergoes the discrete cosine transform (DCT).

Does JPEG use overlapping DCT blocks?

The goal of DCT transform coding is to minimize the number of retained transform coefficients while keeping distortion at an acceptable this http URL JPEG, it is done in 8X8 non overlapping blocks. It divides an image into blocks of equal size and processes each block independently.