[theora-dev] dead DCSearchPoints code

[Mike Melanson]

On Sat, 14 Jun 2003, Ralph Giles wrote:

> Dan,
>
> In reviewing the code, derf came across the DCSearchPoints array in
> QuadCodeDisplayFragments(), encode.c:696. It looks like it specifies a
> search order for nearby coded fragments for prediction if there isn't a
> nearest neighbor. However, the upper search bound is defined as *0*, so
> the search loop (line 917) is never executed and it always falls back
> to the last coded fragment.
>
> This table and supporting code is duplicated on the decode side in
> dct_decode.c around lines 1022 and 1191.
>
> Derf thought this code was similarly bypassed in VP3 as well. I enabled
> it and tested a couple of files, but it didn't make an appreciable
> difference in efficiency. Therefore it seems reasonable to just take it
> out as dead code. I wanted to ask what you knew about it first, and
> make sure we're not breaking lossless VP3 transcode.

        I can confirm that the search point coding stuff is not used in
VP3. I brought this up in February:
  http://www.xiph.org/archives/theora-dev/200302/0026.html


--
	-Mike Melanson

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