In one paper i read giving values bits/pixel in the range 0.25-2.?what does it mean?will it affect the psnr?psnr is dependent upon B,dynamic range,does bits/pixel(rate) has any relation with dynamic range also?

 

The number of distinct colors that can be represented by a pixel depends on the number of bits per pixel. A 1 bpp image uses 1-bit for each pixel, so each pixel can be either on or off. Each additional bit doubles the number of colors available, so a 2 bpp image can have 4 colors, and a 3 bpp image can have 8 colors:

• 1 bpp, 2^1 = 2 colors
• 2 bpp, 2^2 = 4 colors
• 3 bpp, 2^3 = 8 colors....

Peak Signal to Noise Ratio (PSNR) is the ratio between the maximum possible power of a signal and the power of corrupting noise that affects the fidelity of its representation.
For example,

PSNR = 10 * log10 (M^2/Ms);

where: M is the maximum possible pixel value of the image (if you using 8 bits per sample, M is 255); Ms is mean squared error (MSE).

 

what about the gray scale image ?in the particular paper they have given bpp from 0.5 -2 range? so psnr doesnt depend on bpp?

 

what about the gray scale image ?in the particular so psnr doesnt depend on bpp?

Look at mathematical formula that defines PSNR. In the mathematical formula there is a term denoted by "M" which, according to its definition, is directly proportional to bpp. So, we can say that: PSNR depend on bpp.

 

thank u for the reply.what does it mean to give manually bits/pixel or compression rate from 0.25 to 2