[FFmpeg-devel] [PATCH] avfilter: add anoisesrc

[James Almer]

On 11/4/2015 3:19 PM, Kyle Swanson wrote:
> Signed-off-by: Kyle Swanson <k at ylo.ph>
> diff --git a/libavfilter/asrc_anoisesrc.c b/libavfilter/asrc_anoisesrc.c
> new file mode 100644
> index 0000000..d008d67
> --- /dev/null
> +++ b/libavfilter/asrc_anoisesrc.c
> @@ -0,0 +1,222 @@
> +/*
> + * Copyright (c) 2015 Kyle Swanson <k at ylo.ph>.
> + *
> + * 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 <float.h>
> +
> +#include "libavutil/opt.h"
> +#include "audio.h"
> +#include "avfilter.h"
> +#include "internal.h"
> +#include "libavutil/lfg.h"
> +
> +typedef struct {
> +    const AVClass *class;
> +    int sample_rate;
> +    double amplitude;
> +    int64_t dur;
> +    char *color;
> +    int seed;

uint32_t.

Also, why not use av_get_random_seed() when no seed is specified?
In that case both this and the AVOptions below should be int64_t, and the
range of values -1 to UINT32_MAX, with -1 as default.

See f_perms.c

> +
> +    int infinite;
> +    double (*filter)(double white, double *buf);
> +    double* buf;
> +    int buf_size;
> +    AVLFG c;
> +} ANoiseSrcContext;
> +
> +#define OFFSET(x) offsetof(ANoiseSrcContext, x)
> +#define FLAGS AV_OPT_FLAG_AUDIO_PARAM|AV_OPT_FLAG_FILTERING_PARAM
> +
> +static const AVOption anoisesrc_options[] = {
> +    { "sample_rate",  "set sample rate",  OFFSET(sample_rate),  AV_OPT_TYPE_INT,       {.i64 = 48000},    15,        INT_MAX,   FLAGS },
> +    { "r",            "set sample rate",  OFFSET(sample_rate),  AV_OPT_TYPE_INT,       {.i64 = 48000},    15,        INT_MAX,   FLAGS },
> +    { "amplitude",    "set amplitude",    OFFSET(amplitude),    AV_OPT_TYPE_DOUBLE,    {.dbl = 1.},       0.,        1.,        FLAGS },
> +    { "a",            "set amplitude",    OFFSET(amplitude),    AV_OPT_TYPE_DOUBLE,    {.dbl = 1.},       0.,        1.,        FLAGS },
> +    { "duration",     "set duration",     OFFSET(dur),          AV_OPT_TYPE_DURATION,  {.i64 = 0},       0,         INT64_MAX, FLAGS },
> +    { "d",            "set duration",     OFFSET(dur),          AV_OPT_TYPE_DURATION,  {.i64 = 0},       0,         INT64_MAX, FLAGS },
> +    { "color",        "set noise color",  OFFSET(color),        AV_OPT_TYPE_STRING,    {.str = "white"},  CHAR_MIN,  CHAR_MAX,  FLAGS },
> +    { "colour",       "set noise color",  OFFSET(color),        AV_OPT_TYPE_STRING,    {.str = "white"},  CHAR_MIN,  CHAR_MAX,  FLAGS },
> +    { "c",            "set noise color",  OFFSET(color),        AV_OPT_TYPE_STRING,    {.str = "white"},  CHAR_MIN,  CHAR_MAX,  FLAGS },
> +    { "seed",         "set random seed",  OFFSET(seed),         AV_OPT_TYPE_INT,       {.i64 = 0},        0,         UINT_MAX,   FLAGS },
> +    { "s",            "set random seed",  OFFSET(seed),         AV_OPT_TYPE_INT,       {.i64 = 0},        0,         UINT_MAX,   FLAGS },
> +    {NULL}
> +};