[FFmpeg-cvslog] ac3enc: use MUL64() to multiply fixed-point coefficients

Justin Ruggles justin.ruggles
Wed Mar 9 22:47:48 CET 2011

On 03/09/2011 04:27 PM, Justin Ruggles wrote:

> On 03/09/2011 04:07 PM, Justin Ruggles wrote:
>> On 03/09/2011 02:05 PM, Michael Niedermayer wrote:
>>> The output of the MDCT should be more than 16bit.
>>> If thats not the case theres some quality that could be gained, at least at
>>> the high bitrate side IMHO
>> Hmmm... you bring up a good point about quality though.  The final
>> post-rotation does CMUL() which right shifts by 15.  We could possibly
>> gain some quality by having the post-rotation not right shift and adjust
>> the coefficient scaling accordingly.
> Nice.
> http://www.flickr.com/photos/justinruggles/5512657751/

Oops. I even made a mistake on that one. This one is better.



More information about the ffmpeg-cvslog mailing list