skip flag is set, even if it was coded as zero, if a block had no coefficients

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I think the code that does this (vp9_decodeframe.c:decode_block()) stems from 
vp8, where it was possible to disable coding of the skip flag. That feature was 
removed in vp9:

    // Prediction
    vp9_dec_build_inter_predictors_sb(pbi, xd, mi_row, mi_col, bsize);

    // Reconstruction
    if (!mbmi->skip) {
      int eobtotal = 0;
      struct inter_args arg = {cm, xd, r, counts, &eobtotal, y_dequant,
                               uv_dequant};
      vp9_foreach_transformed_block(xd, bsize, reconstruct_inter_block, &arg);
      if (!less8x8 && eobtotal == 0)
        mbmi->skip = 1;  // skip loopfilter
    }

However, the comment is wrong; we don't just skip loopfilter, we also affect 
bitstream decoding (since this is used for contextualization of coding of 
future blocks). I guess this code should just be removed in vp10, or possibly 
be replaced by a flag that is purely used in the loopfilter, not used in 20 
places in the bitstream spec.

Original issue reported on code.google.com by rsbul...@gmail.com on 4 Jun 2015 at 11:50

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Original comment by fgalli...@google.com on 18 Jun 2015 at 10:11

• Changed state: Available

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Original comment by ya...@google.com on 10 Jul 2015 at 11:11

• Added labels: Hotlist-VP10-must-fix

[GoogleCodeExporter]

Original comment by ya...@google.com on 14 Jul 2015 at 4:42

• Added labels: Component-libvpx, Type-Enhancement

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Original comment by ya...@google.com on 12 Aug 2015 at 10:06

• Changed state: Assigned