H.264 解码器函数流程

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while (decode_one_frame(img, input, snr) != EOS)
..........//进入解码阶段，对每一帧进行解码
.
.
.while ((currSlice->next_header != EOS && currSlice->next_header != SOP))
{
    current_header = read_new_slice();

    if (current_header == EOS)
    {
      exit_picture();
      return EOS;
    }

    decode_slice(img, inp, current_header);

    img->newframe = 0;
    img->current_slice_nr++;
}//对每一帧的slice进行解码，silce是由宏块构成的，接下来，应该是对以宏块的单元进行解码

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.........
// decode main slice information
if ((current_header == SOP || current_header == SOS) && currSlice->ei_flag == 0)
    decode_one_slice(img,inp);
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.......
while (end_of_slice == FALSE) // loop over macroblocks
{

#if TRACE
fprintf(p_trace,"/n*********** POC: %i (I/P) MB: %i Slice: %i Type %d **********/n", img->ThisPOC, img->current_mb_nr, img->current_slice_nr, img->type);
#endif

    // Initializes the current macroblock
    start_macroblock(img,inp, img->current_mb_nr);
    // Get the syntax elements from the NAL
    read_flag = read_one_macroblock(img,inp);
    decode_one_macroblock(img,inp);

    if(img->MbaffFrameFlag && dec_picture->mb_field[img->current_mb_nr])
    {
      img->num_ref_idx_l0_active >>= 1;
      img->num_ref_idx_l1_active >>= 1;
    }

    ercWriteMBMODEandMV(img,inp);

    end_of_slice=exit_macroblock(img,inp,(!img->MbaffFrameFlag||img->current_mb_nr%2));
}
.......