Re: [FFmpeg-devel] [PATCH] avfilter: add acontrast filter

[Paul B Mahol]

On 11/18/17, Rostislav Pehlivanov  wrote:
> On 18 November 2017 at 10:44, Paul B Mahol  wrote:
>
>> Signed-off-by: Paul B Mahol 
>> ---
>>  doc/filters.texi   |  10 +++
>>  libavfilter/Makefile   |   1 +
>>  libavfilter/af_acontrast.c | 219 ++
>> +++
>>  libavfilter/allfilters.c   |   1 +
>>  4 files changed, 231 insertions(+)
>>  create mode 100644 libavfilter/af_acontrast.c
>>
>> diff --git a/doc/filters.texi b/doc/filters.texi
>> index 5d99437871..e35952510b 100644
>> --- a/doc/filters.texi
>> +++ b/doc/filters.texi
>> @@ -429,6 +429,16 @@ How much to use compressed signal in output. Default
>> is 1.
>>  Range is between 0 and 1.
>>  @end table
>>
>> +@section acontrast
>> +Simple audio dynamic range commpression/expansion filter.
>> +
>> +The filter accepts the following options:
>> +
>> +@table @option
>> +@item c
>> +Set contrast. Default is 33. Allowed range is between 0 and 100.
>> +@end table
>> +
>>  @section acopy
>>
>>  Copy the input audio source unchanged to the output. This is mainly
>> useful for
>> diff --git a/libavfilter/Makefile b/libavfilter/Makefile
>> index 9acae3ff5b..71c6333a52 100644
>> --- a/libavfilter/Makefile
>> +++ b/libavfilter/Makefile
>> @@ -31,6 +31,7 @@ OBJS-$(CONFIG_QSVVPP)+= qsvvpp.o
>>  # audio filters
>>  OBJS-$(CONFIG_ABENCH_FILTER) += f_bench.o
>>  OBJS-$(CONFIG_ACOMPRESSOR_FILTER)+= af_sidechaincompress.o
>> +OBJS-$(CONFIG_ACONTRAST_FILTER)  += af_acontrast.o
>>  OBJS-$(CONFIG_ACOPY_FILTER)  += af_acopy.o
>>  OBJS-$(CONFIG_ACROSSFADE_FILTER) += af_afade.o
>>  OBJS-$(CONFIG_ACRUSHER_FILTER)   += af_acrusher.o
>> diff --git a/libavfilter/af_acontrast.c b/libavfilter/af_acontrast.c
>> new file mode 100644
>> index 00..38de08ffe5
>> --- /dev/null
>> +++ b/libavfilter/af_acontrast.c
>> @@ -0,0 +1,219 @@
>> +/*
>> + * Copyright (c) 2008 Rob Sykes
>> + * Copyright (c) 2017 Paul B Mahol
>> + *
>> + * 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 "libavutil/channel_layout.h"
>> +#include "libavutil/opt.h"
>> +#include "avfilter.h"
>> +#include "audio.h"
>> +#include "formats.h"
>> +
>> +typedef struct AudioContrastContext {
>> +const AVClass *class;
>> +float contrast;
>> +void (*filter)(void **dst, const void **src,
>> +   int nb_samples, int channels, float contrast);
>> +} AudioContrastContext;
>> +
>> +#define OFFSET(x) offsetof(AudioContrastContext, x)
>> +#define A AV_OPT_FLAG_AUDIO_PARAM|AV_OPT_FLAG_FILTERING_PARAM
>> +
>> +static const AVOption acontrast_options[] = {
>> +{ "c", "set contrast", OFFSET(contrast), AV_OPT_TYPE_FLOAT,
>> {.dbl=33}, 0, 100, A },
>>
>
> "contrast" instead of "c"? Not sure if single letter options are a good
> idea.
>
>
>
>> +{ NULL }
>> +};
>> +
>> +AVFILTER_DEFINE_CLASS(acontrast);
>> +
>> +static int query_formats(AVFilterContext *ctx)
>> +{
>> +AVFilterFormats *formats = NULL;
>> +AVFilterChannelLayouts *layouts = NULL;
>> +static const enum AVSampleFormat sample_fmts[] = {
>> +AV_SAMPLE_FMT_FLT, AV_SAMPLE_FMT_FLTP,
>> +AV_SAMPLE_FMT_DBL, AV_SAMPLE_FMT_DBLP,
>> +AV_SAMPLE_FMT_NONE
>> +};
>> +int ret;
>> +
>> +formats = ff_make_format_list(sample_fmts);
>> +if (!formats)
>> +return AVERROR(ENOMEM);
>> +ret = ff_set_common_formats(ctx, formats);
>> +if (ret < 0)
>> +return ret;
>> +
>> +layouts = ff_all_channel_counts();
>> +if (!layouts)
>> +return AVERROR(ENOMEM);
>> +
>> +ret = ff_set_common_channel_layouts(ctx, layouts);
>> +if (ret < 0)
>> +return ret;
>> +
>> +formats = ff_all_samplerates();
>> +return ff_set_common_samplerates(ctx, formats);
>> +}
>> +
>> +static void filter_flt(void **d, const void **s,
>> +   int nb_samples, int channels,
>> +   float contrast)
>> +{
>> +const float *src = s[0];
>> +float *dst = d[0];
>> +int n, c;
>> +
>> +for (n = 0; n < nb_samples; n++) {
>> +for (c = 0; c < channels; c++) {
>> +   

Re: [FFmpeg-devel] [PATCH] avfilter: add acontrast filter

[Rostislav Pehlivanov]

On 18 November 2017 at 10:44, Paul B Mahol  wrote:

> Signed-off-by: Paul B Mahol 
> ---
>  doc/filters.texi   |  10 +++
>  libavfilter/Makefile   |   1 +
>  libavfilter/af_acontrast.c | 219 ++
> +++
>  libavfilter/allfilters.c   |   1 +
>  4 files changed, 231 insertions(+)
>  create mode 100644 libavfilter/af_acontrast.c
>
> diff --git a/doc/filters.texi b/doc/filters.texi
> index 5d99437871..e35952510b 100644
> --- a/doc/filters.texi
> +++ b/doc/filters.texi
> @@ -429,6 +429,16 @@ How much to use compressed signal in output. Default
> is 1.
>  Range is between 0 and 1.
>  @end table
>
> +@section acontrast
> +Simple audio dynamic range commpression/expansion filter.
> +
> +The filter accepts the following options:
> +
> +@table @option
> +@item c
> +Set contrast. Default is 33. Allowed range is between 0 and 100.
> +@end table
> +
>  @section acopy
>
>  Copy the input audio source unchanged to the output. This is mainly
> useful for
> diff --git a/libavfilter/Makefile b/libavfilter/Makefile
> index 9acae3ff5b..71c6333a52 100644
> --- a/libavfilter/Makefile
> +++ b/libavfilter/Makefile
> @@ -31,6 +31,7 @@ OBJS-$(CONFIG_QSVVPP)+= qsvvpp.o
>  # audio filters
>  OBJS-$(CONFIG_ABENCH_FILTER) += f_bench.o
>  OBJS-$(CONFIG_ACOMPRESSOR_FILTER)+= af_sidechaincompress.o
> +OBJS-$(CONFIG_ACONTRAST_FILTER)  += af_acontrast.o
>  OBJS-$(CONFIG_ACOPY_FILTER)  += af_acopy.o
>  OBJS-$(CONFIG_ACROSSFADE_FILTER) += af_afade.o
>  OBJS-$(CONFIG_ACRUSHER_FILTER)   += af_acrusher.o
> diff --git a/libavfilter/af_acontrast.c b/libavfilter/af_acontrast.c
> new file mode 100644
> index 00..38de08ffe5
> --- /dev/null
> +++ b/libavfilter/af_acontrast.c
> @@ -0,0 +1,219 @@
> +/*
> + * Copyright (c) 2008 Rob Sykes
> + * Copyright (c) 2017 Paul B Mahol
> + *
> + * 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 "libavutil/channel_layout.h"
> +#include "libavutil/opt.h"
> +#include "avfilter.h"
> +#include "audio.h"
> +#include "formats.h"
> +
> +typedef struct AudioContrastContext {
> +const AVClass *class;
> +float contrast;
> +void (*filter)(void **dst, const void **src,
> +   int nb_samples, int channels, float contrast);
> +} AudioContrastContext;
> +
> +#define OFFSET(x) offsetof(AudioContrastContext, x)
> +#define A AV_OPT_FLAG_AUDIO_PARAM|AV_OPT_FLAG_FILTERING_PARAM
> +
> +static const AVOption acontrast_options[] = {
> +{ "c", "set contrast", OFFSET(contrast), AV_OPT_TYPE_FLOAT,
> {.dbl=33}, 0, 100, A },
>

"contrast" instead of "c"? Not sure if single letter options are a good
idea.



> +{ NULL }
> +};
> +
> +AVFILTER_DEFINE_CLASS(acontrast);
> +
> +static int query_formats(AVFilterContext *ctx)
> +{
> +AVFilterFormats *formats = NULL;
> +AVFilterChannelLayouts *layouts = NULL;
> +static const enum AVSampleFormat sample_fmts[] = {
> +AV_SAMPLE_FMT_FLT, AV_SAMPLE_FMT_FLTP,
> +AV_SAMPLE_FMT_DBL, AV_SAMPLE_FMT_DBLP,
> +AV_SAMPLE_FMT_NONE
> +};
> +int ret;
> +
> +formats = ff_make_format_list(sample_fmts);
> +if (!formats)
> +return AVERROR(ENOMEM);
> +ret = ff_set_common_formats(ctx, formats);
> +if (ret < 0)
> +return ret;
> +
> +layouts = ff_all_channel_counts();
> +if (!layouts)
> +return AVERROR(ENOMEM);
> +
> +ret = ff_set_common_channel_layouts(ctx, layouts);
> +if (ret < 0)
> +return ret;
> +
> +formats = ff_all_samplerates();
> +return ff_set_common_samplerates(ctx, formats);
> +}
> +
> +static void filter_flt(void **d, const void **s,
> +   int nb_samples, int channels,
> +   float contrast)
> +{
> +const float *src = s[0];
> +float *dst = d[0];
> +int n, c;
> +
> +for (n = 0; n < nb_samples; n++) {
> +for (c = 0; c < channels; c++) {
> +double d = src[c] * M_PI_2;
> +
> +dst[c] = sin(d + contrast * sin(d * 4));
>

sinf() instead of sin()



> +}
> +
> +dst += c;
> +src += c;
> +}
> +}
> +
> +static