[FFmpeg-devel] [PATCH] DCA floating point output

Måns Rullgård mans
Mon Apr 26 13:42:47 CEST 2010

FB2000 <flybird2k at gmail.com> writes:

> 2010/4/26 M?ns Rullg?rd <mans at mansr.com>
>> Trust me, it will.  It will spend 5x more time in the conversion than
>> in the decoder itself.  I've seen it.
> I am not sure about how efficient the DCA decoding part works. At least when
> downmixing is involved, I see a lot of floating point multiplications. Take
> DCA_3F2R to DCA_STEREO downmixing for example, it's done as:

I plan do those with SIMD later.

> So you see, for each sample, there will be 5 multiplications. I guess adding
> another floating point division at output won't hurt that much.
> I assume downmixing 5.1 channel to stereo is the scenario most people used
> when it comes to DTS, especial for those who is still on old hardware.

Stop assuming stuff and listen to those who know what they're talking
about (that would be me).

M?ns Rullg?rd
mans at mansr.com

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