[FFmpeg-devel] [libav-devel] [PATCH] s302m: fix resampling for 16 and 24bits.

[Alex Converse]

On Sat, Jun 4, 2011 at 6:07 AM, Clément Bœsch <ubitux at gmail.com> wrote:
> Hi,
>
> Here are two fixes for the SMPTE 302M codec.
>
> 24 bits resampling:
>    input:
>        offset:  00 11 22 33 44 55 66
>        nibbles: AB CD EF #G HI JK L# ('#'=unused)
>    wanted output (2*32bits):
>        nibbles: 76 54 32 10
>        output1: FE DC BA 00
>        output2: LK JI HG 00
>
>    #G (offset 3) is truncated and reversed so it becomes G0 and so it
>    only needs a <<4 shift to set nibble 2 (it will be mixed with nibble
>    3 if <<8).
>

This chunk looks obviously OK by inspection

> 16 bits resampling:
>    input:
>        offset:  00 11 22 33 44
>        nibbles: AB CD #E FG H#
>    wanted output (2*16bits):
>        nibbles: 32 10
>        output1: DC BA
>        output2: HG FE
>
>    Here, the issue is similar, we get: HGF0|E0 instead of HGF0|(E0>>4).
>

OK

yes I see that this is removing wide band noise on the right channel

> 16-bits fix is taken from FFmbc, and the second has been discussed on
> IRC with Baptiste.
>

Approved