[FFmpeg-devel] [PATCH 1/3] DCA: break out lfe_interpolation_fir() inner loops to a function

[Måns Rullgård]

Mans Rullgard <mans at mansr.com> writes:

> new file mode 100644
> index 0000000..614aa49
> --- /dev/null
> +++ b/libavcodec/dcadsp.c
> @@ -0,0 +1,52 @@
> +/*
> + * Copyright (c) 2004 Gildas Bazin
> + * Copyright (c) 2004 Benjamin Zores
> + * Copyright (c) 2006 Benjamin Larsson
> + * Copyright (c) 2007 Konstantin Shishkov
> + * Copyright (c) 2010 Mans Rullgard <mans at mansr.com>
> + *
> + * This file is part of FFmpeg.
> + *
> + * FFmpeg is free software; you can redistribute it and/or
> + * modify it under the terms of the GNU Lesser General Public
> + * License as published by the Free Software Foundation; either
> + * version 2.1 of the License, or (at your option) any later version.
> + *
> + * FFmpeg is distributed in the hope that it will be useful,
> + * but WITHOUT ANY WARRANTY; without even the implied warranty of
> + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
> + * Lesser General Public License for more details.
> + *
> + * You should have received a copy of the GNU Lesser General Public
> + * License along with FFmpeg; if not, write to the Free Software
> + * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
> + */
> +
> +#include "dcadsp.h"
> +
> +static void dca_lfe_fir_c(float *out, const float *in, const float *coefs,
> +                          int decifactor, float scale, float bias)
> +{
> +    float *out2 = out + decifactor;
> +    const float *cf0 = coefs;
> +    const float *cf1 = coefs + 256;
> +    int j, k;
> +
> +    /* One decimated sample generates 2*decifactor interpolated ones */
> +    for (k = 0; k < decifactor; k++) {
> +        float v0 = 0.0;
> +        float v1 = 0.0;
> +        for (j = 0; j < 256 / decifactor; j++) {
> +            float s = in[-j];
> +            v0 += s * *cf0++;
> +            v1 += s * *--cf1;
> +        }
> +        *out++  = (v0 * scale) + bias;
> +        *out2++ = (v1 * scale) + bias;
> +    }
> +}

Does anyone remember who actually wrote this function?  I don't think
having all those names in the copyright header makes sense.

-- 
M?ns Rullg?rd
mans at mansr.com