[FFmpeg-devel] [PATCH 1/2] Move float windowing code in mp3 decoder to dsputils

[Vitor Sessak]

On 06/18/2010 02:45 PM, Michael Niedermayer wrote:
> On Thu, Jun 17, 2010 at 05:34:48PM +0200, Vitor Sessak wrote:
>> On 06/17/2010 04:50 PM, M?ns Rullg?rd wrote:
>>> Vitor Sessak<vitor1001 at gmail.com>   writes:
>>>
>>>> $subj. It introduces some code duplication that I have no good idea
>>>> how to avoid.
>>>
>>> Can we please not clutter dsputil with even more codec-specific stuff?
>>
>> As attached?
> [...]
>>   /* layer 3 huffman tables */
>> @@ -178,7 +180,7 @@
>>   void ff_mpa_synth_filter_float(MPA_INT *synth_buf_ptr, int *synth_buf_offset,
>>                            MPA_INT *window, int *dither_state,
>>                            OUT_INT *samples, int incr,
>> -                         INTFLOAT sb_samples[SBLIMIT]);
>> +                         INTFLOAT sb_samples[SBLIMIT], MPADecodeContext *s);
>
> whats the context needd for ?

To get a pointer to the apply_window_mp3() function:

> +/* 32 sub band synthesis filter. Input: 32 sub band samples, Output:
> +   32 samples. */
> +/* XXX: optimize by avoiding ring buffer usage */
> +#if CONFIG_FLOAT
> +void ff_mpa_synth_filter_float(float *synth_buf_ptr,
> +                               int *synth_buf_offset,
> +                               float *window, int *dither_state,
> +                               float *samples, int incr,
> +                               float sb_samples[SBLIMIT],
> +                               MPADecodeContext *s)
> +{
> +    float *synth_buf;
> +    int offset;
> +
> +    offset = *synth_buf_offset;
> +    synth_buf = synth_buf_ptr + offset;
> +
> +    dct32(synth_buf, sb_samples);
> +    s->apply_window_mp3(synth_buf, window, dither_state, samples, incr);
        ^^^

It will be also useful later to get a DCTContext for the asm-optimized 
dct32()...

-Vitor