[FFmpeg-devel] [PATCH] RDFT for Bink audio

[Michael Niedermayer]

On Thu, Jan 15, 2009 at 11:52:20AM -0500, Alex Converse wrote:
[...]
> +int ff_rdft_init(RDFTContext *s, int nbits, int inverse)
> +{
> +    int n = 1 << nbits;
> +    int i;
> +    const double theta = (1-2*inverse)*2*M_PI/n;
> +
> +    s->nbits = nbits;
> +    s->inverse = inverse;
> +
> +    if (ff_fft_init(&s->fft, nbits-1, !inverse) < 0)
> +        goto fail;
> +
> +    s->tcos = av_malloc((n>>2) * sizeof(FFTSample));
> +    if (!s->tcos)
> +        goto fail;
> +    s->tsin = av_malloc((n>>2) * sizeof(FFTSample));
> +    if (!s->tsin)
> +        goto fail;
> +    for (i = 0; i < (n>>2); i++) {
> +        s->tcos[i] = cos(i*theta);
> +        s->tsin[i] = sin(i*theta);
> +    }

we have a large number of sin and cos tables already
see ff_sine_* / ff_cos_*, no need to duplicate them in each context

[...]
-- 
Michael     GnuPG fingerprint: 9FF2128B147EF6730BADF133611EC787040B0FAB

I know you won't believe me, but the highest form of Human Excellence is
to question oneself and others. -- Socrates
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