[Mp4-tech] reference of intra and inter Macroblcok!

[Zhao Ran]

> 1)Macroblocks' prediction in I frame can only take macroblock in the same
> slice as reference, then when one frame has two slices, then does
> macroblock in one slice can take the macroblock in another slice of the
> same frame as reference?

For intra prediction, only those macroblock in the same slice are available, which make the error resilience reliable.
> 2)P frame can have intra macroblock and inter macroblock. as far as inter
> macroblock is concerned,does it only take macroblocks in other frames
> decoded before as reference? or other rule? and what about reference of
> intra macroblocks in the P frame?

The first one is just as you said. For the frame have not decoded yet,  it is impossible to be used for the prediction of current frame.
As far as intra macroblocks,  if constrained_intra_pred_flag equal to 0, any macroblocks in the same slice is allowed for prediction; else if constrained_intra_pred_flag equal to 1, only the macorblocks coded in intra prediction mode in the same slice can be used for prediction.