Error in example boolean decoder in bitstream guide

[Mehul Tikekar]

Hi,
In section 7.3 of the bitstream guide, init_bool_decoder() reads 24 bytes into value when it is supposed to read in 2 bytes. I compared this with the libvpx source code, and the two ought to match when VP8_BD_VALUE_SIZE is 16. This is because the read_bool function in the guide does SPLIT = split << 8, while the actual vp8dx_decode_bool does bigsplit = split << (VP8_BD_VALUE_SIZE - 8). And when VP8_BD_VALUE_SIZE is 16, you'll see that vp8dx_start_decode_c reads in 2 bytes.

Also, on the encoder side, the flush_bool_encoder function does some strange things while the source code in dboolhuff.c simply encodes 32 0's. The two are probably equivalent, but clearly the actual code is easier to understand.

Regards,
  Mehul  

[Lou Quillio]

Hopefully this clears it up:

https://review.webmproject.org/#change,1604

Thanks.

LQ

--
Lou Quillio
Webmaster
WebMProject.org

[Mehul Tikekar]

Thanks. There is a small typo in section 16.03 - the function vp8_prob *vp8_mv_ref_probs() should return "mv_ref_p" instead of "p".

Regards,
   Mehul

[Brooss]

On Jan 26, 9:06 am, Lou Quillio <louquil...@google.com> wrote:

This was also issue #52 on the bug tracker.
http://code.google.com/p/webm/issues/detail?id=52