decoding jpeg

hi guys

i'm working on my project to decode jpeg files. i did well untill the dequantization stage. all my calculations are all corect. i confirmed it with jpegsnoop software.

but then the problem is there, this software doesnt provide the values after idct process.

i did the idct process, and then converted the YCbCr values to RGB. but, i didnt get the right RGB values. i got the idct matrix from matlab. and there is this "gain of dct transform". in an example, it said that after dequantized the values, you need to divide them with this "gain of dct tranform". well, i havent done that.

does this "gain of dct transform" refers to idct matrix?? has anyone done this kind of project before??

thanks