boundary strengh of macroblcock!

[angelzhang]

hi,experts
In the H.264 standard,value of boundary strength is calculate according to
judgement of different macroblocks, such as mb_type and the prediction mode
etc. but I am confused why value of boundary strengh of IntraMb (here 4 or
3) are larger than that of InterMb(2,1,or0). is it mean that the filter
strength of IntraMb is stronger than InterMb? why?

and another question is that whether deblock filter is only used for P
frame and I frame don't need deblock filter.

thanks in advance.
best regards
angel

[angelzhang]

please give me some hints?

[akupenguin]

Intra are deblocked stronger because there is more opportunity for blocking artifacts: Inter blocks usually code only a small residual, so the pixel values are mostly from the previous frame, which was already deblocked.
All frames are deblocked, there's nothing special about I.

[angelzhang]

hi,akupenguin
Thanks for your answer. and i get it now. I have get a wrong idea of deblock filter process. I frame's prediction is made before deblock filter doesn't mean that it need not deblock filter process.

then,can you tell me the mechanism in the encoder of choosing inter or intra code mode of a certain slice of macroblock?

best regards
angel

[akupenguin]

Originally posted by angelzhang
then,can you tell me the mechanism in the encoder of choosing inter or intra code mode of a certain slice of macroblock? There are lots of ways to decide, and this is the main feature that distinguishes different codecs.
A reasonably simple and fast comparison method is "Sum of Absolute Hadamard Transformed Differences", which approximates the number of bits it would take to encode the macroblock in a given mode. (If you want more details, there are many papers on the subject, but I can't suggest one in particular.)

[angelzhang]

I know what's your mean, and i will go to look some special applications material. thanks a lot1

angel