[FFmpeg-devel] atrac1 decoder and aea demuxer rev 6

Vitor Sessak vitor1001
Sun Sep 6 21:26:36 CEST 2009


Benjamin Larsson wrote:
> Changes:
> 
> Lots of cosmetics fixes.
> Optimized the mdct window use.
> Removed one memcopy.
> Changed some code.
> 
> Did not do anything to the qmf routines that will be shared with atrac3
> as it will be a svn copy and I'll take comments on that when the code is
>  split out in it's own file.

[...]

> +
> +    /* round, convert to 16bit and interleave */
> +    if (q->channels == 1) {
> +        /* mono */
> +        for (i = 0; i<AT1_SU_SAMPLES; i++)
> +            samples[i]     = av_clipf(q->out_samples[0][i], -32700./(1<<15), 32700./(1<<15));
> +    } else {
> +        /* stereo */
> +        for (i = 0; i < AT1_SU_SAMPLES; i++) {
> +            samples[i*2]   = av_clipf(q->out_samples[0][i], -32700./(1<<15), 32700./(1<<15));
> +            samples[i*2+1] = av_clipf(q->out_samples[1][i], -32700./(1<<15), 32700./(1<<15));
> +        }
> +    }

av_clipf() is slow...

-Vitor



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