diff mbox

[FFmpeg-devel] avfilter: add arbitrary audio FIR filter

Message ID 20170501083020.5250-1-onemda@gmail.com
State Superseded
Headers show

Commit Message

Paul B Mahol May 1, 2017, 8:30 a.m. UTC
Signed-off-by: Paul B Mahol <onemda@gmail.com>
---
 configure                   |   2 +
 doc/filters.texi            |  10 ++
 libavfilter/Makefile        |   1 +
 libavfilter/af_afirfilter.c | 409 ++++++++++++++++++++++++++++++++++++++++++++
 libavfilter/allfilters.c    |   1 +
 5 files changed, 423 insertions(+)
 create mode 100644 libavfilter/af_afirfilter.c

Comments

Muhammad Faiz May 2, 2017, 7:25 a.m. UTC | #1
On Mon, May 1, 2017 at 3:30 PM, Paul B Mahol <onemda@gmail.com> wrote:
> Signed-off-by: Paul B Mahol <onemda@gmail.com>
> ---
>  configure                   |   2 +
>  doc/filters.texi            |  10 ++
>  libavfilter/Makefile        |   1 +
>  libavfilter/af_afirfilter.c | 409 ++++++++++++++++++++++++++++++++++++++++++++
>  libavfilter/allfilters.c    |   1 +
>  5 files changed, 423 insertions(+)
>  create mode 100644 libavfilter/af_afirfilter.c
>
> diff --git a/configure b/configure
> index b3cb5b0..7fc7af4 100755
> --- a/configure
> +++ b/configure
> @@ -3078,6 +3078,8 @@ unix_protocol_select="network"
>  # filters
>  afftfilt_filter_deps="avcodec"
>  afftfilt_filter_select="fft"
> +afirfilter_filter_deps="avcodec"
> +afirfilter_filter_select="fft"
>  amovie_filter_deps="avcodec avformat"
>  aresample_filter_deps="swresample"
>  ass_filter_deps="libass"
> diff --git a/doc/filters.texi b/doc/filters.texi
> index 119e747..ea343d1 100644
> --- a/doc/filters.texi
> +++ b/doc/filters.texi
> @@ -878,6 +878,16 @@ afftfilt="1-clip((b/nb)*b,0,1)"
>  @end example
>  @end itemize
>
> +@section afirfilter
> +
> +Apply an Arbitary Frequency Impulse Response filter.
> +
> +This filter uses second stream as FIR coefficients.
> +If second stream holds single channel, it will be used
> +for all input channels in first stream, otherwise
> +number of channels in second stream must be same as
> +number of channels in first stream.
> +
>  @anchor{aformat}
>  @section aformat
>
> diff --git a/libavfilter/Makefile b/libavfilter/Makefile
> index 66c36e4..1a0f24b 100644
> --- a/libavfilter/Makefile
> +++ b/libavfilter/Makefile
> @@ -38,6 +38,7 @@ OBJS-$(CONFIG_AEMPHASIS_FILTER)              += af_aemphasis.o
>  OBJS-$(CONFIG_AEVAL_FILTER)                  += aeval.o
>  OBJS-$(CONFIG_AFADE_FILTER)                  += af_afade.o
>  OBJS-$(CONFIG_AFFTFILT_FILTER)               += af_afftfilt.o window_func.o
> +OBJS-$(CONFIG_AFIRFILTER_FILTER)             += af_afirfilter.o
>  OBJS-$(CONFIG_AFORMAT_FILTER)                += af_aformat.o
>  OBJS-$(CONFIG_AGATE_FILTER)                  += af_agate.o
>  OBJS-$(CONFIG_AINTERLEAVE_FILTER)            += f_interleave.o
> diff --git a/libavfilter/af_afirfilter.c b/libavfilter/af_afirfilter.c
> new file mode 100644
> index 0000000..ef2488a
> --- /dev/null
> +++ b/libavfilter/af_afirfilter.c
> @@ -0,0 +1,409 @@
> +/*
> + * 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
> + */
> +
> +/**
> + * @file
> + * An arbitrary audio FIR filter
> + */
> +
> +#include "libavutil/audio_fifo.h"
> +#include "libavutil/avassert.h"
> +#include "libavutil/channel_layout.h"
> +#include "libavutil/common.h"
> +#include "libavutil/opt.h"
> +#include "libavcodec/avfft.h"
> +
> +#include "audio.h"
> +#include "avfilter.h"
> +#include "formats.h"
> +#include "internal.h"
> +
> +typedef struct FIRContext {
> +    const AVClass *class;
> +
> +    int n;
> +    int eof_coeffs;
> +    int have_coeffs;
> +    int nb_taps;
> +    int fft_length;
> +    int nb_channels;
> +    int one2many;
> +
> +    FFTContext *fft, *ifft;
> +    FFTComplex **fft_data;
> +    FFTComplex **fft_coef;

Probably you may use rdft for performance reason.



> +
> +    AVAudioFifo *fifo[2];
> +    AVFrame *in[2];
> +    AVFrame *buffer;
> +    int64_t pts;
> +    int hop_size;
> +    int start, end;
> +} FIRContext;
> +
> +static int fir_filter(FIRContext *s, AVFilterLink *outlink)
> +{
> +    AVFilterContext *ctx = outlink->src;
> +    int start = s->start, end = s->end;
> +    int ret = 0, n, ch, j, k;
> +    int nb_samples;
> +    AVFrame *out;
> +
> +    nb_samples = FFMIN(s->fft_length, av_audio_fifo_size(s->fifo[0]));
> +
> +    s->in[0] = ff_get_audio_buffer(ctx->inputs[0], nb_samples);
> +    if (!s->in[0])
> +        return AVERROR(ENOMEM);
> +
> +    av_audio_fifo_peek(s->fifo[0], (void **)s->in[0]->extended_data, nb_samples);
> +
> +    for (ch = 0; ch < outlink->channels; ch++) {
> +        const float *src = (float *)s->in[0]->extended_data[ch];
> +        float *buf = (float *)s->buffer->extended_data[ch];
> +        FFTComplex *fft_data = s->fft_data[ch];
> +        FFTComplex *fft_coef = s->fft_coef[ch];
> +
> +        memset(fft_data, 0, sizeof(*fft_data) * s->fft_length);
> +        for (n = 0; n < nb_samples; n++) {
> +            fft_data[n].re = src[n];
> +            fft_data[n].im = 0;
> +        }
> +
> +        av_fft_permute(s->fft, fft_data);
> +        av_fft_calc(s->fft, fft_data);
> +
> +        fft_data[0].re *= fft_coef[0].re;
> +        fft_data[0].im *= fft_coef[0].im;
> +        for (n = 1; n < s->fft_length; n++) {
> +            const float re = fft_data[n].re;
> +            const float im = fft_data[n].im;
> +
> +            fft_data[n].re = re * fft_coef[n].re - im * fft_coef[n].im;
> +            fft_data[n].im = re * fft_coef[n].im + im * fft_coef[n].re;
> +        }
> +
> +        av_fft_permute(s->ifft, fft_data);
> +        av_fft_calc(s->ifft, fft_data);
> +
> +        start = s->start;
> +        end = s->end;
> +        k = end;
> +
> +        for (n = 0, j = start; j < k && n < s->fft_length; n++, j++) {
> +            buf[j] = fft_data[n].re;
> +        }
> +
> +        for (; n < s->fft_length; n++, j++) {
> +            buf[j] = fft_data[n].re;
> +        }
> +
> +        start += s->hop_size;
> +        end = j;
> +    }
> +
> +    s->start = start;
> +    s->end   = end;
> +
> +    if (start >= nb_samples) {
> +        float *dst, *buf;
> +
> +        start -= nb_samples;
> +        end   -= nb_samples;
> +
> +        s->start = start;
> +        s->end = end;
> +
> +        out = ff_get_audio_buffer(outlink, nb_samples);
> +        if (!out)
> +            return AVERROR(ENOMEM);
> +
> +        out->pts = s->pts;
> +        s->pts += nb_samples;

Is pts handled correctly here? Seem it is not derived from input pts.


> +
> +        for (ch = 0; ch < s->nb_channels; ch++) {
> +            dst = (float *)out->extended_data[ch];
> +            buf = (float *)s->buffer->extended_data[ch];
> +
> +            for (n = 0; n < nb_samples; n++)
> +                dst[n] = buf[n];
> +            memmove(buf, buf + nb_samples, nb_samples * 4);
> +        }
> +
> +        ret = ff_filter_frame(outlink, out);
> +    }
> +
> +    av_audio_fifo_drain(s->fifo[0], FFMIN(nb_samples, s->hop_size));
> +    av_frame_free(&s->in[0]);
> +
> +    return ret;
> +}
> +
> +static int convert_coeffs(AVFilterContext *ctx)
> +{
> +    FIRContext *s = ctx->priv;
> +    int ch, n;
> +
> +    s->nb_taps = av_audio_fifo_size(s->fifo[1]);
> +    if (s->nb_taps > 32768) {
> +        av_log(ctx, AV_LOG_ERROR, "Too big number of taps: %d > 32768.\n", s->nb_taps);
> +        return AVERROR(EINVAL);
> +    }
> +
> +    for (n = 1; (1 << n) < s->nb_taps; n++);
> +    s->n = n + 2;
> +    s->fft_length = 1 << s->n;
> +
> +    for (ch = 0; ch < ctx->inputs[0]->channels; ch++) {
> +        s->fft_data[ch] = av_calloc(s->fft_length, sizeof(**s->fft_data));
> +        if (!s->fft_data[ch])
> +            return AVERROR(ENOMEM);
> +    }
> +
> +    for (ch = 0; ch < ctx->inputs[1]->channels; ch++) {
> +        s->fft_coef[ch] = av_calloc(s->fft_length, sizeof(**s->fft_coef));
> +        if (!s->fft_coef[ch])
> +            return AVERROR(ENOMEM);
> +    }
> +
> +    s->hop_size = s->fft_length - s->nb_taps + 1;
> +    if (s->hop_size <= 0) {
> +        av_log(ctx, AV_LOG_ERROR, "Too big number of taps.\n");
> +        return AVERROR(EINVAL);
> +    }
> +
> +    s->buffer = ff_get_audio_buffer(ctx->inputs[0], s->fft_length * 2);
> +    if (!s->buffer)
> +        return AVERROR(ENOMEM);
> +
> +    s->fft  = av_fft_init(s->n, 0);
> +    s->ifft = av_fft_init(s->n, 1);
> +    if (!s->fft || !s->ifft)
> +        return AVERROR(ENOMEM);
> +
> +    s->in[1] = ff_get_audio_buffer(ctx->inputs[1], s->nb_taps);
> +    if (!s->in[1])
> +        return AVERROR(ENOMEM);
> +
> +    av_audio_fifo_read(s->fifo[1], (void **)s->in[1]->extended_data, s->nb_taps);
> +    for (ch = 0; ch < ctx->inputs[1]->channels; ch++) {
> +        FFTComplex *fft_coef = s->fft_coef[ch];
> +        const float *re = (const float *)s->in[1]->extended_data[!s->one2many * ch];
> +        const float scale = 1.f / s->fft_length;
> +        const int offset = (s->fft_length - s->nb_taps);
> +
> +        memset(fft_coef, 0, sizeof(*fft_coef) * s->fft_length);
> +        for (n = 0; n < s->nb_taps; n++) {
> +            fft_coef[n + offset].re = re[n] * scale;
> +        }
> +        av_fft_permute(s->fft, fft_coef);
> +        av_fft_calc(s->fft, fft_coef);
> +    }
> +
> +    av_frame_free(&s->in[1]);
> +    s->have_coeffs = 1;
> +
> +    return 0;
> +}
> +
> +static int read_coeffs(AVFilterLink *link, AVFrame *frame)
> +{
> +    AVFilterContext *ctx = link->dst;
> +    FIRContext *s = ctx->priv;
> +
> +    av_audio_fifo_write(s->fifo[1], (void **)frame->extended_data,
> +                        frame->nb_samples);
> +    av_frame_free(&frame);
> +
> +    return 0;
> +}
> +
> +static int filter_frame(AVFilterLink *link, AVFrame *frame)
> +{
> +    AVFilterContext *ctx = link->dst;
> +    FIRContext *s = ctx->priv;
> +    AVFilterLink *outlink = ctx->outputs[0];
> +    int ret = 0;
> +
> +    av_audio_fifo_write(s->fifo[0], (void **)frame->extended_data,
> +                        frame->nb_samples);
> +    av_frame_free(&frame);
> +
> +    if (!s->have_coeffs && s->eof_coeffs) {
> +        ret = convert_coeffs(ctx);
> +        if (ret < 0)
> +            return ret;
> +    }
> +
> +    if (s->have_coeffs) {
> +        while (av_audio_fifo_size(s->fifo[0]) >= s->fft_length) {
> +            ret = fir_filter(s, outlink);
> +            if (ret < 0)
> +                break;
> +        }
> +    }
> +    return ret;
> +}
> +
> +static int request_frame(AVFilterLink *outlink)
> +{
> +    AVFilterContext *ctx = outlink->src;
> +    FIRContext *s = ctx->priv;
> +    int ret;
> +
> +    if (!s->eof_coeffs) {
> +        ret = ff_request_frame(ctx->inputs[1]);
> +        if (ret == AVERROR_EOF) {
> +            s->eof_coeffs = 1;
> +            ret = 0;
> +        }
> +        return ret;
> +    }
> +    ret = ff_request_frame(ctx->inputs[0]);
> +    if (ret == AVERROR_EOF && s->have_coeffs) {
> +        while (av_audio_fifo_size(s->fifo[0]) > 0) {
> +            ret = fir_filter(s, outlink);
> +            if (ret < 0)
> +                return ret;
> +        }
> +        ret = AVERROR_EOF;
> +    }
> +    return ret;
> +}
> +
> +static int query_formats(AVFilterContext *ctx)
> +{
> +    AVFilterFormats *formats;
> +    AVFilterChannelLayouts *layouts = NULL;
> +    static const enum AVSampleFormat sample_fmts[] = {
> +        AV_SAMPLE_FMT_FLTP,
> +        AV_SAMPLE_FMT_NONE
> +    };
> +    int ret, i;
> +
> +    layouts = ff_all_channel_counts();
> +    if ((ret = ff_channel_layouts_ref(layouts, &ctx->outputs[0]->in_channel_layouts)) < 0)
> +        return ret;
> +
> +    for (i = 0; i < 2; i++) {
> +        layouts = ff_all_channel_counts();
> +        if ((ret = ff_channel_layouts_ref(layouts, &ctx->inputs[i]->out_channel_layouts)) < 0)
> +            return ret;
> +    }
> +
> +    formats = ff_make_format_list(sample_fmts);
> +    if ((ret = ff_set_common_formats(ctx, formats)) < 0)
> +        return ret;
> +
> +    formats = ff_all_samplerates();
> +    return ff_set_common_samplerates(ctx, formats);
> +}
> +
> +static int config_output(AVFilterLink *outlink)
> +{
> +    AVFilterContext *ctx = outlink->src;
> +    FIRContext *s = ctx->priv;
> +
> +    if (ctx->inputs[0]->channels != ctx->inputs[1]->channels &&
> +        ctx->inputs[1]->channels != 1) {
> +        av_log(ctx, AV_LOG_ERROR,
> +               "Second input must have same number of channels as first input or "
> +               "exactly 1 channel.\n");
> +        return AVERROR(EINVAL);
> +    }
> +
> +    s->one2many = ctx->inputs[1]->channels == 1;
> +    outlink->sample_rate = ctx->inputs[0]->sample_rate;
> +    outlink->time_base   = ctx->inputs[0]->time_base;
> +    outlink->channel_layout = ctx->inputs[0]->channel_layout;
> +    outlink->channels = ctx->inputs[0]->channels;
> +
> +    s->fifo[0] = av_audio_fifo_alloc(ctx->inputs[0]->format, ctx->inputs[0]->channels, 1024);
> +    s->fifo[1] = av_audio_fifo_alloc(ctx->inputs[1]->format, ctx->inputs[1]->channels, 1024);
> +    if (!s->fifo[0] || !s->fifo[1])
> +        return AVERROR(ENOMEM);
> +
> +    s->fft_data = av_calloc(outlink->channels, sizeof(*s->fft_data));
> +    s->fft_coef = av_calloc(ctx->inputs[1]->channels, sizeof(*s->fft_coef));
> +    if (!s->fft_data || !s->fft_coef)
> +        return AVERROR(ENOMEM);
> +    s->nb_channels = outlink->channels;
> +
> +    return 0;
> +}
> +
> +static av_cold void uninit(AVFilterContext *ctx)
> +{
> +    FIRContext *s = ctx->priv;
> +    int ch;
> +
> +    for (ch = 0; ch < s->nb_channels; ch++) {
> +        if (s->fft_data)
> +            av_freep(&s->fft_data[ch]);
> +    }
> +    av_freep(&s->fft_data);
> +
> +    for (ch = 0; ch < s->nb_channels; ch++) {
> +        if (s->fft_coef)
> +            av_freep(&s->fft_coef[ch]);
> +    }
> +    av_freep(&s->fft_coef);
> +
> +    av_fft_end(s->fft);
> +    av_fft_end(s->ifft);
> +
> +    av_frame_free(&s->in[0]);
> +    av_frame_free(&s->in[1]);
> +
> +    av_audio_fifo_free(s->fifo[0]);
> +    av_audio_fifo_free(s->fifo[1]);
> +}
> +
> +static const AVFilterPad afirfilter_inputs[] = {
> +    {
> +        .name           = "main",
> +        .type           = AVMEDIA_TYPE_AUDIO,
> +        .filter_frame   = filter_frame,
> +    },{
> +        .name           = "coefficients",
> +        .type           = AVMEDIA_TYPE_AUDIO,
> +        .filter_frame   = read_coeffs,
> +    },
> +    { NULL }
> +};
> +
> +static const AVFilterPad afirfilter_outputs[] = {
> +    {
> +        .name          = "default",
> +        .type          = AVMEDIA_TYPE_AUDIO,
> +        .config_props  = config_output,
> +        .request_frame = request_frame,
> +    },
> +    { NULL }
> +};
> +
> +AVFilter ff_af_afirfilter = {
> +    .name           = "afirfilter",
> +    .description    = NULL_IF_CONFIG_SMALL("Apply Finite Impulse Response filter with supplied coefficients in 2nd stream."),
> +    .priv_size      = sizeof(FIRContext),
> +    .query_formats  = query_formats,
> +    .uninit         = uninit,
> +    .inputs         = afirfilter_inputs,
> +    .outputs        = afirfilter_outputs,
> +};
> diff --git a/libavfilter/allfilters.c b/libavfilter/allfilters.c
> index 8fb87eb..8bfe1ae 100644
> --- a/libavfilter/allfilters.c
> +++ b/libavfilter/allfilters.c
> @@ -50,6 +50,7 @@ static void register_all(void)
>      REGISTER_FILTER(AEVAL,          aeval,          af);
>      REGISTER_FILTER(AFADE,          afade,          af);
>      REGISTER_FILTER(AFFTFILT,       afftfilt,       af);
> +    REGISTER_FILTER(AFIRFILTER,     afirfilter,     af);
>      REGISTER_FILTER(AFORMAT,        aformat,        af);
>      REGISTER_FILTER(AGATE,          agate,          af);
>      REGISTER_FILTER(AINTERLEAVE,    ainterleave,    af);
> --
> 2.9.3
>
> _______________________________________________
> ffmpeg-devel mailing list
> ffmpeg-devel@ffmpeg.org
> http://ffmpeg.org/mailman/listinfo/ffmpeg-devel
Paul B Mahol May 2, 2017, 6:47 p.m. UTC | #2
On 5/2/17, Muhammad Faiz <mfcc64@gmail.com> wrote:
> On Mon, May 1, 2017 at 3:30 PM, Paul B Mahol <onemda@gmail.com> wrote:
>> Signed-off-by: Paul B Mahol <onemda@gmail.com>
>> ---
>>  configure                   |   2 +
>>  doc/filters.texi            |  10 ++
>>  libavfilter/Makefile        |   1 +
>>  libavfilter/af_afirfilter.c | 409
>> ++++++++++++++++++++++++++++++++++++++++++++
>>  libavfilter/allfilters.c    |   1 +
>>  5 files changed, 423 insertions(+)
>>  create mode 100644 libavfilter/af_afirfilter.c
>>
>> diff --git a/configure b/configure
>> index b3cb5b0..7fc7af4 100755
>> --- a/configure
>> +++ b/configure
>> @@ -3078,6 +3078,8 @@ unix_protocol_select="network"
>>  # filters
>>  afftfilt_filter_deps="avcodec"
>>  afftfilt_filter_select="fft"
>> +afirfilter_filter_deps="avcodec"
>> +afirfilter_filter_select="fft"
>>  amovie_filter_deps="avcodec avformat"
>>  aresample_filter_deps="swresample"
>>  ass_filter_deps="libass"
>> diff --git a/doc/filters.texi b/doc/filters.texi
>> index 119e747..ea343d1 100644
>> --- a/doc/filters.texi
>> +++ b/doc/filters.texi
>> @@ -878,6 +878,16 @@ afftfilt="1-clip((b/nb)*b,0,1)"
>>  @end example
>>  @end itemize
>>
>> +@section afirfilter
>> +
>> +Apply an Arbitary Frequency Impulse Response filter.
>> +
>> +This filter uses second stream as FIR coefficients.
>> +If second stream holds single channel, it will be used
>> +for all input channels in first stream, otherwise
>> +number of channels in second stream must be same as
>> +number of channels in first stream.
>> +
>>  @anchor{aformat}
>>  @section aformat
>>
>> diff --git a/libavfilter/Makefile b/libavfilter/Makefile
>> index 66c36e4..1a0f24b 100644
>> --- a/libavfilter/Makefile
>> +++ b/libavfilter/Makefile
>> @@ -38,6 +38,7 @@ OBJS-$(CONFIG_AEMPHASIS_FILTER)              +=
>> af_aemphasis.o
>>  OBJS-$(CONFIG_AEVAL_FILTER)                  += aeval.o
>>  OBJS-$(CONFIG_AFADE_FILTER)                  += af_afade.o
>>  OBJS-$(CONFIG_AFFTFILT_FILTER)               += af_afftfilt.o
>> window_func.o
>> +OBJS-$(CONFIG_AFIRFILTER_FILTER)             += af_afirfilter.o
>>  OBJS-$(CONFIG_AFORMAT_FILTER)                += af_aformat.o
>>  OBJS-$(CONFIG_AGATE_FILTER)                  += af_agate.o
>>  OBJS-$(CONFIG_AINTERLEAVE_FILTER)            += f_interleave.o
>> diff --git a/libavfilter/af_afirfilter.c b/libavfilter/af_afirfilter.c
>> new file mode 100644
>> index 0000000..ef2488a
>> --- /dev/null
>> +++ b/libavfilter/af_afirfilter.c
>> @@ -0,0 +1,409 @@
>> +/*
>> + * 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
>> + */
>> +
>> +/**
>> + * @file
>> + * An arbitrary audio FIR filter
>> + */
>> +
>> +#include "libavutil/audio_fifo.h"
>> +#include "libavutil/avassert.h"
>> +#include "libavutil/channel_layout.h"
>> +#include "libavutil/common.h"
>> +#include "libavutil/opt.h"
>> +#include "libavcodec/avfft.h"
>> +
>> +#include "audio.h"
>> +#include "avfilter.h"
>> +#include "formats.h"
>> +#include "internal.h"
>> +
>> +typedef struct FIRContext {
>> +    const AVClass *class;
>> +
>> +    int n;
>> +    int eof_coeffs;
>> +    int have_coeffs;
>> +    int nb_taps;
>> +    int fft_length;
>> +    int nb_channels;
>> +    int one2many;
>> +
>> +    FFTContext *fft, *ifft;
>> +    FFTComplex **fft_data;
>> +    FFTComplex **fft_coef;
>
> Probably you may use rdft for performance reason.

I will concentrate on correctness of output first.

>
>
>
>> +
>> +    AVAudioFifo *fifo[2];
>> +    AVFrame *in[2];
>> +    AVFrame *buffer;
>> +    int64_t pts;
>> +    int hop_size;
>> +    int start, end;
>> +} FIRContext;
>> +
>> +static int fir_filter(FIRContext *s, AVFilterLink *outlink)
>> +{
>> +    AVFilterContext *ctx = outlink->src;
>> +    int start = s->start, end = s->end;
>> +    int ret = 0, n, ch, j, k;
>> +    int nb_samples;
>> +    AVFrame *out;
>> +
>> +    nb_samples = FFMIN(s->fft_length, av_audio_fifo_size(s->fifo[0]));
>> +
>> +    s->in[0] = ff_get_audio_buffer(ctx->inputs[0], nb_samples);
>> +    if (!s->in[0])
>> +        return AVERROR(ENOMEM);
>> +
>> +    av_audio_fifo_peek(s->fifo[0], (void **)s->in[0]->extended_data,
>> nb_samples);
>> +
>> +    for (ch = 0; ch < outlink->channels; ch++) {
>> +        const float *src = (float *)s->in[0]->extended_data[ch];
>> +        float *buf = (float *)s->buffer->extended_data[ch];
>> +        FFTComplex *fft_data = s->fft_data[ch];
>> +        FFTComplex *fft_coef = s->fft_coef[ch];
>> +
>> +        memset(fft_data, 0, sizeof(*fft_data) * s->fft_length);
>> +        for (n = 0; n < nb_samples; n++) {
>> +            fft_data[n].re = src[n];
>> +            fft_data[n].im = 0;
>> +        }
>> +
>> +        av_fft_permute(s->fft, fft_data);
>> +        av_fft_calc(s->fft, fft_data);
>> +
>> +        fft_data[0].re *= fft_coef[0].re;
>> +        fft_data[0].im *= fft_coef[0].im;
>> +        for (n = 1; n < s->fft_length; n++) {
>> +            const float re = fft_data[n].re;
>> +            const float im = fft_data[n].im;
>> +
>> +            fft_data[n].re = re * fft_coef[n].re - im * fft_coef[n].im;
>> +            fft_data[n].im = re * fft_coef[n].im + im * fft_coef[n].re;
>> +        }
>> +
>> +        av_fft_permute(s->ifft, fft_data);
>> +        av_fft_calc(s->ifft, fft_data);
>> +
>> +        start = s->start;
>> +        end = s->end;
>> +        k = end;
>> +
>> +        for (n = 0, j = start; j < k && n < s->fft_length; n++, j++) {
>> +            buf[j] = fft_data[n].re;
>> +        }
>> +
>> +        for (; n < s->fft_length; n++, j++) {
>> +            buf[j] = fft_data[n].re;
>> +        }
>> +
>> +        start += s->hop_size;
>> +        end = j;
>> +    }
>> +
>> +    s->start = start;
>> +    s->end   = end;
>> +
>> +    if (start >= nb_samples) {
>> +        float *dst, *buf;
>> +
>> +        start -= nb_samples;
>> +        end   -= nb_samples;
>> +
>> +        s->start = start;
>> +        s->end = end;
>> +
>> +        out = ff_get_audio_buffer(outlink, nb_samples);
>> +        if (!out)
>> +            return AVERROR(ENOMEM);
>> +
>> +        out->pts = s->pts;
>> +        s->pts += nb_samples;
>
> Is pts handled correctly here? Seem it is not derived from input pts.
>

It can not be derived in any other way.
Muhammad Faiz May 3, 2017, 9:12 a.m. UTC | #3
On Wed, May 3, 2017 at 1:47 AM, Paul B Mahol <onemda@gmail.com> wrote:
> On 5/2/17, Muhammad Faiz <mfcc64@gmail.com> wrote:
>> On Mon, May 1, 2017 at 3:30 PM, Paul B Mahol <onemda@gmail.com> wrote:
>>> Signed-off-by: Paul B Mahol <onemda@gmail.com>
>>> ---
>>>  configure                   |   2 +
>>>  doc/filters.texi            |  10 ++
>>>  libavfilter/Makefile        |   1 +
>>>  libavfilter/af_afirfilter.c | 409
>>> ++++++++++++++++++++++++++++++++++++++++++++
>>>  libavfilter/allfilters.c    |   1 +
>>>  5 files changed, 423 insertions(+)
>>>  create mode 100644 libavfilter/af_afirfilter.c
>>>
>>> diff --git a/configure b/configure
>>> index b3cb5b0..7fc7af4 100755
>>> --- a/configure
>>> +++ b/configure
>>> @@ -3078,6 +3078,8 @@ unix_protocol_select="network"
>>>  # filters
>>>  afftfilt_filter_deps="avcodec"
>>>  afftfilt_filter_select="fft"
>>> +afirfilter_filter_deps="avcodec"
>>> +afirfilter_filter_select="fft"
>>>  amovie_filter_deps="avcodec avformat"
>>>  aresample_filter_deps="swresample"
>>>  ass_filter_deps="libass"
>>> diff --git a/doc/filters.texi b/doc/filters.texi
>>> index 119e747..ea343d1 100644
>>> --- a/doc/filters.texi
>>> +++ b/doc/filters.texi
>>> @@ -878,6 +878,16 @@ afftfilt="1-clip((b/nb)*b,0,1)"
>>>  @end example
>>>  @end itemize
>>>
>>> +@section afirfilter
>>> +
>>> +Apply an Arbitary Frequency Impulse Response filter.
>>> +
>>> +This filter uses second stream as FIR coefficients.
>>> +If second stream holds single channel, it will be used
>>> +for all input channels in first stream, otherwise
>>> +number of channels in second stream must be same as
>>> +number of channels in first stream.
>>> +
>>>  @anchor{aformat}
>>>  @section aformat
>>>
>>> diff --git a/libavfilter/Makefile b/libavfilter/Makefile
>>> index 66c36e4..1a0f24b 100644
>>> --- a/libavfilter/Makefile
>>> +++ b/libavfilter/Makefile
>>> @@ -38,6 +38,7 @@ OBJS-$(CONFIG_AEMPHASIS_FILTER)              +=
>>> af_aemphasis.o
>>>  OBJS-$(CONFIG_AEVAL_FILTER)                  += aeval.o
>>>  OBJS-$(CONFIG_AFADE_FILTER)                  += af_afade.o
>>>  OBJS-$(CONFIG_AFFTFILT_FILTER)               += af_afftfilt.o
>>> window_func.o
>>> +OBJS-$(CONFIG_AFIRFILTER_FILTER)             += af_afirfilter.o
>>>  OBJS-$(CONFIG_AFORMAT_FILTER)                += af_aformat.o
>>>  OBJS-$(CONFIG_AGATE_FILTER)                  += af_agate.o
>>>  OBJS-$(CONFIG_AINTERLEAVE_FILTER)            += f_interleave.o
>>> diff --git a/libavfilter/af_afirfilter.c b/libavfilter/af_afirfilter.c
>>> new file mode 100644
>>> index 0000000..ef2488a
>>> --- /dev/null
>>> +++ b/libavfilter/af_afirfilter.c
>>> @@ -0,0 +1,409 @@
>>> +/*
>>> + * 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
>>> + */
>>> +
>>> +/**
>>> + * @file
>>> + * An arbitrary audio FIR filter
>>> + */
>>> +
>>> +#include "libavutil/audio_fifo.h"
>>> +#include "libavutil/avassert.h"
>>> +#include "libavutil/channel_layout.h"
>>> +#include "libavutil/common.h"
>>> +#include "libavutil/opt.h"
>>> +#include "libavcodec/avfft.h"
>>> +
>>> +#include "audio.h"
>>> +#include "avfilter.h"
>>> +#include "formats.h"
>>> +#include "internal.h"
>>> +
>>> +typedef struct FIRContext {
>>> +    const AVClass *class;
>>> +
>>> +    int n;
>>> +    int eof_coeffs;
>>> +    int have_coeffs;
>>> +    int nb_taps;
>>> +    int fft_length;
>>> +    int nb_channels;
>>> +    int one2many;
>>> +
>>> +    FFTContext *fft, *ifft;
>>> +    FFTComplex **fft_data;
>>> +    FFTComplex **fft_coef;
>>
>> Probably you may use rdft for performance reason.
>
> I will concentrate on correctness of output first.

OK.

>
>>
>>
>>
>>> +
>>> +    AVAudioFifo *fifo[2];
>>> +    AVFrame *in[2];
>>> +    AVFrame *buffer;
>>> +    int64_t pts;
>>> +    int hop_size;
>>> +    int start, end;
>>> +} FIRContext;
>>> +
>>> +static int fir_filter(FIRContext *s, AVFilterLink *outlink)
>>> +{
>>> +    AVFilterContext *ctx = outlink->src;
>>> +    int start = s->start, end = s->end;
>>> +    int ret = 0, n, ch, j, k;
>>> +    int nb_samples;
>>> +    AVFrame *out;
>>> +
>>> +    nb_samples = FFMIN(s->fft_length, av_audio_fifo_size(s->fifo[0]));
>>> +
>>> +    s->in[0] = ff_get_audio_buffer(ctx->inputs[0], nb_samples);
>>> +    if (!s->in[0])
>>> +        return AVERROR(ENOMEM);
>>> +
>>> +    av_audio_fifo_peek(s->fifo[0], (void **)s->in[0]->extended_data,
>>> nb_samples);
>>> +
>>> +    for (ch = 0; ch < outlink->channels; ch++) {
>>> +        const float *src = (float *)s->in[0]->extended_data[ch];
>>> +        float *buf = (float *)s->buffer->extended_data[ch];
>>> +        FFTComplex *fft_data = s->fft_data[ch];
>>> +        FFTComplex *fft_coef = s->fft_coef[ch];
>>> +
>>> +        memset(fft_data, 0, sizeof(*fft_data) * s->fft_length);
>>> +        for (n = 0; n < nb_samples; n++) {
>>> +            fft_data[n].re = src[n];
>>> +            fft_data[n].im = 0;
>>> +        }
>>> +
>>> +        av_fft_permute(s->fft, fft_data);
>>> +        av_fft_calc(s->fft, fft_data);
>>> +
>>> +        fft_data[0].re *= fft_coef[0].re;
>>> +        fft_data[0].im *= fft_coef[0].im;
>>> +        for (n = 1; n < s->fft_length; n++) {
>>> +            const float re = fft_data[n].re;
>>> +            const float im = fft_data[n].im;
>>> +
>>> +            fft_data[n].re = re * fft_coef[n].re - im * fft_coef[n].im;
>>> +            fft_data[n].im = re * fft_coef[n].im + im * fft_coef[n].re;
>>> +        }
>>> +
>>> +        av_fft_permute(s->ifft, fft_data);
>>> +        av_fft_calc(s->ifft, fft_data);
>>> +
>>> +        start = s->start;
>>> +        end = s->end;
>>> +        k = end;
>>> +
>>> +        for (n = 0, j = start; j < k && n < s->fft_length; n++, j++) {
>>> +            buf[j] = fft_data[n].re;
>>> +        }
>>> +
>>> +        for (; n < s->fft_length; n++, j++) {
>>> +            buf[j] = fft_data[n].re;
>>> +        }
>>> +
>>> +        start += s->hop_size;
>>> +        end = j;
>>> +    }
>>> +
>>> +    s->start = start;
>>> +    s->end   = end;
>>> +
>>> +    if (start >= nb_samples) {
>>> +        float *dst, *buf;
>>> +
>>> +        start -= nb_samples;
>>> +        end   -= nb_samples;
>>> +
>>> +        s->start = start;
>>> +        s->end = end;
>>> +
>>> +        out = ff_get_audio_buffer(outlink, nb_samples);
>>> +        if (!out)
>>> +            return AVERROR(ENOMEM);
>>> +
>>> +        out->pts = s->pts;
>>> +        s->pts += nb_samples;
>>
>> Is pts handled correctly here? Seem it is not derived from input pts.
>>
>
> It can not be derived in any other way.

Probably, at least, first pts should be derived from input pts.
Also, is time_base always 1/sample_rate?

Thank's.
Moritz Barsnick May 3, 2017, 11:34 a.m. UTC | #4
On Mon, May 01, 2017 at 10:30:20 +0200, Paul B Mahol wrote:
> +    .name           = "afirfilter",

Does a filter have any reason to have "filter" in its name? It seems
unusual.

Moritz
Muhammad Faiz May 5, 2017, 1:02 p.m. UTC | #5
On Wed, May 3, 2017 at 4:12 PM, Muhammad Faiz <mfcc64@gmail.com> wrote:
> On Wed, May 3, 2017 at 1:47 AM, Paul B Mahol <onemda@gmail.com> wrote:
>> On 5/2/17, Muhammad Faiz <mfcc64@gmail.com> wrote:
>>> On Mon, May 1, 2017 at 3:30 PM, Paul B Mahol <onemda@gmail.com> wrote:
>>>> Signed-off-by: Paul B Mahol <onemda@gmail.com>
>>>> ---
>>>>  configure                   |   2 +
>>>>  doc/filters.texi            |  10 ++
>>>>  libavfilter/Makefile        |   1 +
>>>>  libavfilter/af_afirfilter.c | 409
>>>> ++++++++++++++++++++++++++++++++++++++++++++
>>>>  libavfilter/allfilters.c    |   1 +
>>>>  5 files changed, 423 insertions(+)
>>>>  create mode 100644 libavfilter/af_afirfilter.c
>>>>
>>>> diff --git a/configure b/configure
>>>> index b3cb5b0..7fc7af4 100755
>>>> --- a/configure
>>>> +++ b/configure
>>>> @@ -3078,6 +3078,8 @@ unix_protocol_select="network"
>>>>  # filters
>>>>  afftfilt_filter_deps="avcodec"
>>>>  afftfilt_filter_select="fft"
>>>> +afirfilter_filter_deps="avcodec"
>>>> +afirfilter_filter_select="fft"
>>>>  amovie_filter_deps="avcodec avformat"
>>>>  aresample_filter_deps="swresample"
>>>>  ass_filter_deps="libass"
>>>> diff --git a/doc/filters.texi b/doc/filters.texi
>>>> index 119e747..ea343d1 100644
>>>> --- a/doc/filters.texi
>>>> +++ b/doc/filters.texi
>>>> @@ -878,6 +878,16 @@ afftfilt="1-clip((b/nb)*b,0,1)"
>>>>  @end example
>>>>  @end itemize
>>>>
>>>> +@section afirfilter
>>>> +
>>>> +Apply an Arbitary Frequency Impulse Response filter.
>>>> +
>>>> +This filter uses second stream as FIR coefficients.
>>>> +If second stream holds single channel, it will be used
>>>> +for all input channels in first stream, otherwise
>>>> +number of channels in second stream must be same as
>>>> +number of channels in first stream.
>>>> +
>>>>  @anchor{aformat}
>>>>  @section aformat
>>>>
>>>> diff --git a/libavfilter/Makefile b/libavfilter/Makefile
>>>> index 66c36e4..1a0f24b 100644
>>>> --- a/libavfilter/Makefile
>>>> +++ b/libavfilter/Makefile
>>>> @@ -38,6 +38,7 @@ OBJS-$(CONFIG_AEMPHASIS_FILTER)              +=
>>>> af_aemphasis.o
>>>>  OBJS-$(CONFIG_AEVAL_FILTER)                  += aeval.o
>>>>  OBJS-$(CONFIG_AFADE_FILTER)                  += af_afade.o
>>>>  OBJS-$(CONFIG_AFFTFILT_FILTER)               += af_afftfilt.o
>>>> window_func.o
>>>> +OBJS-$(CONFIG_AFIRFILTER_FILTER)             += af_afirfilter.o
>>>>  OBJS-$(CONFIG_AFORMAT_FILTER)                += af_aformat.o
>>>>  OBJS-$(CONFIG_AGATE_FILTER)                  += af_agate.o
>>>>  OBJS-$(CONFIG_AINTERLEAVE_FILTER)            += f_interleave.o
>>>> diff --git a/libavfilter/af_afirfilter.c b/libavfilter/af_afirfilter.c
>>>> new file mode 100644
>>>> index 0000000..ef2488a
>>>> --- /dev/null
>>>> +++ b/libavfilter/af_afirfilter.c
>>>> @@ -0,0 +1,409 @@
>>>> +/*
>>>> + * 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
>>>> + */
>>>> +
>>>> +/**
>>>> + * @file
>>>> + * An arbitrary audio FIR filter
>>>> + */
>>>> +
>>>> +#include "libavutil/audio_fifo.h"
>>>> +#include "libavutil/avassert.h"
>>>> +#include "libavutil/channel_layout.h"
>>>> +#include "libavutil/common.h"
>>>> +#include "libavutil/opt.h"
>>>> +#include "libavcodec/avfft.h"
>>>> +
>>>> +#include "audio.h"
>>>> +#include "avfilter.h"
>>>> +#include "formats.h"
>>>> +#include "internal.h"
>>>> +
>>>> +typedef struct FIRContext {
>>>> +    const AVClass *class;
>>>> +
>>>> +    int n;
>>>> +    int eof_coeffs;
>>>> +    int have_coeffs;
>>>> +    int nb_taps;
>>>> +    int fft_length;
>>>> +    int nb_channels;
>>>> +    int one2many;
>>>> +
>>>> +    FFTContext *fft, *ifft;
>>>> +    FFTComplex **fft_data;
>>>> +    FFTComplex **fft_coef;
>>>
>>> Probably you may use rdft for performance reason.
>>
>> I will concentrate on correctness of output first.
>
> OK.
>
>>
>>>
>>>
>>>
>>>> +
>>>> +    AVAudioFifo *fifo[2];
>>>> +    AVFrame *in[2];
>>>> +    AVFrame *buffer;
>>>> +    int64_t pts;
>>>> +    int hop_size;
>>>> +    int start, end;
>>>> +} FIRContext;
>>>> +
>>>> +static int fir_filter(FIRContext *s, AVFilterLink *outlink)
>>>> +{
>>>> +    AVFilterContext *ctx = outlink->src;
>>>> +    int start = s->start, end = s->end;
>>>> +    int ret = 0, n, ch, j, k;
>>>> +    int nb_samples;
>>>> +    AVFrame *out;
>>>> +
>>>> +    nb_samples = FFMIN(s->fft_length, av_audio_fifo_size(s->fifo[0]));
>>>> +
>>>> +    s->in[0] = ff_get_audio_buffer(ctx->inputs[0], nb_samples);
>>>> +    if (!s->in[0])
>>>> +        return AVERROR(ENOMEM);
>>>> +
>>>> +    av_audio_fifo_peek(s->fifo[0], (void **)s->in[0]->extended_data,
>>>> nb_samples);
>>>> +
>>>> +    for (ch = 0; ch < outlink->channels; ch++) {
>>>> +        const float *src = (float *)s->in[0]->extended_data[ch];
>>>> +        float *buf = (float *)s->buffer->extended_data[ch];
>>>> +        FFTComplex *fft_data = s->fft_data[ch];
>>>> +        FFTComplex *fft_coef = s->fft_coef[ch];
>>>> +
>>>> +        memset(fft_data, 0, sizeof(*fft_data) * s->fft_length);
>>>> +        for (n = 0; n < nb_samples; n++) {
>>>> +            fft_data[n].re = src[n];
>>>> +            fft_data[n].im = 0;
>>>> +        }
>>>> +
>>>> +        av_fft_permute(s->fft, fft_data);
>>>> +        av_fft_calc(s->fft, fft_data);
>>>> +
>>>> +        fft_data[0].re *= fft_coef[0].re;
>>>> +        fft_data[0].im *= fft_coef[0].im;
>>>> +        for (n = 1; n < s->fft_length; n++) {
>>>> +            const float re = fft_data[n].re;
>>>> +            const float im = fft_data[n].im;
>>>> +
>>>> +            fft_data[n].re = re * fft_coef[n].re - im * fft_coef[n].im;
>>>> +            fft_data[n].im = re * fft_coef[n].im + im * fft_coef[n].re;
>>>> +        }
>>>> +
>>>> +        av_fft_permute(s->ifft, fft_data);
>>>> +        av_fft_calc(s->ifft, fft_data);
>>>> +
>>>> +        start = s->start;
>>>> +        end = s->end;
>>>> +        k = end;
>>>> +
>>>> +        for (n = 0, j = start; j < k && n < s->fft_length; n++, j++) {
>>>> +            buf[j] = fft_data[n].re;
>>>> +        }
>>>> +
>>>> +        for (; n < s->fft_length; n++, j++) {
>>>> +            buf[j] = fft_data[n].re;
>>>> +        }
>>>> +
>>>> +        start += s->hop_size;
>>>> +        end = j;
>>>> +    }
>>>> +
>>>> +    s->start = start;
>>>> +    s->end   = end;
>>>> +
>>>> +    if (start >= nb_samples) {
>>>> +        float *dst, *buf;
>>>> +
>>>> +        start -= nb_samples;
>>>> +        end   -= nb_samples;
>>>> +
>>>> +        s->start = start;
>>>> +        s->end = end;
>>>> +
>>>> +        out = ff_get_audio_buffer(outlink, nb_samples);
>>>> +        if (!out)
>>>> +            return AVERROR(ENOMEM);
>>>> +
>>>> +        out->pts = s->pts;
>>>> +        s->pts += nb_samples;
>>>
>>> Is pts handled correctly here? Seem it is not derived from input pts.
>>>
>>
>> It can not be derived in any other way.
>
> Probably, at least, first pts should be derived from input pts.
> Also, is time_base always 1/sample_rate?
>
> Thank's.

Probably, like in asetnsamples filter.

Thank's.
Paul B Mahol May 5, 2017, 7:32 p.m. UTC | #6
On 5/3/17, Moritz Barsnick <barsnick@gmx.net> wrote:
> On Mon, May 01, 2017 at 10:30:20 +0200, Paul B Mahol wrote:
>> +    .name           = "afirfilter",
>
> Does a filter have any reason to have "filter" in its name? It seems
> unusual.
>

Renamed.
Paul B Mahol May 5, 2017, 7:33 p.m. UTC | #7
On 5/5/17, Muhammad Faiz <mfcc64@gmail.com> wrote:
>>>> Is pts handled correctly here? Seem it is not derived from input pts.
>>>>
>>>
>>> It can not be derived in any other way.
>>
>> Probably, at least, first pts should be derived from input pts.
>> Also, is time_base always 1/sample_rate?
>>
>> Thank's.
>
> Probably, like in asetnsamples filter.

Done. Have an idea where artifacst come out for some IRs?
Muhammad Faiz May 6, 2017, midnight UTC | #8
On Sat, May 6, 2017 at 2:33 AM, Paul B Mahol <onemda@gmail.com> wrote:
> On 5/5/17, Muhammad Faiz <mfcc64@gmail.com> wrote:
>>>>> Is pts handled correctly here? Seem it is not derived from input pts.
>>>>>
>>>>
>>>> It can not be derived in any other way.
>>>
>>> Probably, at least, first pts should be derived from input pts.
>>> Also, is time_base always 1/sample_rate?
>>>
>>> Thank's.
>>
>> Probably, like in asetnsamples filter.
>
> Done. Have an idea where artifacst come out for some IRs?

I have no idea what's wrong here? I currently don't understand
partitioned convolution.

My test case:
./ffplay -f lavfi "aevalsrc='if(lt(t,1), if(n,0,1), sin(1000*t*t))',
aformat= channel_layouts=mono, asplit [afir_in0], firequalizer=
zero_phase=on:gain_entry='entry(0, 0); entry(100, -4); entry(1000,
-30); entry(5000, -50); entry(6000, -10); entry(10000, -5)', aformat=
channel_layouts=mono,a
split [merge1], atrim= end_sample=883 [afir_in1]; [afir_in0][afir_in1]
afir, aformat=channel_layouts=mono, [merge1] amerge,
asplit[out0],showspectrum=s=1024x512[out1]"

Note that your old patch didn't generate artifact.

Thank's.
Paul B Mahol May 6, 2017, 7:49 p.m. UTC | #9
On 5/6/17, Muhammad Faiz <mfcc64@gmail.com> wrote:
> On Sat, May 6, 2017 at 2:33 AM, Paul B Mahol <onemda@gmail.com> wrote:
>> On 5/5/17, Muhammad Faiz <mfcc64@gmail.com> wrote:
>>>>>> Is pts handled correctly here? Seem it is not derived from input pts.
>>>>>>
>>>>>
>>>>> It can not be derived in any other way.
>>>>
>>>> Probably, at least, first pts should be derived from input pts.
>>>> Also, is time_base always 1/sample_rate?
>>>>
>>>> Thank's.
>>>
>>> Probably, like in asetnsamples filter.
>>
>> Done. Have an idea where artifacst come out for some IRs?
>
> I have no idea what's wrong here? I currently don't understand
> partitioned convolution.
>
> My test case:
> ./ffplay -f lavfi "aevalsrc='if(lt(t,1), if(n,0,1), sin(1000*t*t))',
> aformat= channel_layouts=mono, asplit [afir_in0], firequalizer=
> zero_phase=on:gain_entry='entry(0, 0); entry(100, -4); entry(1000,
> -30); entry(5000, -50); entry(6000, -10); entry(10000, -5)', aformat=
> channel_layouts=mono,a
> split [merge1], atrim= end_sample=883 [afir_in1]; [afir_in0][afir_in1]
> afir, aformat=channel_layouts=mono, [merge1] amerge,
> asplit[out0],showspectrum=s=1024x512[out1]"
>
> Note that your old patch didn't generate artifact.

Artifacts are gone if you use bigger IR size, >2048.

UPOLS should be rather trivial to understand and to implement.
Muhammad Faiz May 6, 2017, 10:32 p.m. UTC | #10
On Sun, May 7, 2017 at 2:49 AM, Paul B Mahol <onemda@gmail.com> wrote:
> On 5/6/17, Muhammad Faiz <mfcc64@gmail.com> wrote:
>> On Sat, May 6, 2017 at 2:33 AM, Paul B Mahol <onemda@gmail.com> wrote:
>>> On 5/5/17, Muhammad Faiz <mfcc64@gmail.com> wrote:
>>>>>>> Is pts handled correctly here? Seem it is not derived from input pts.
>>>>>>>
>>>>>>
>>>>>> It can not be derived in any other way.
>>>>>
>>>>> Probably, at least, first pts should be derived from input pts.
>>>>> Also, is time_base always 1/sample_rate?
>>>>>
>>>>> Thank's.
>>>>
>>>> Probably, like in asetnsamples filter.
>>>
>>> Done. Have an idea where artifacst come out for some IRs?
>>
>> I have no idea what's wrong here? I currently don't understand
>> partitioned convolution.
>>
>> My test case:
>> ./ffplay -f lavfi "aevalsrc='if(lt(t,1), if(n,0,1), sin(1000*t*t))',
>> aformat= channel_layouts=mono, asplit [afir_in0], firequalizer=
>> zero_phase=on:gain_entry='entry(0, 0); entry(100, -4); entry(1000,
>> -30); entry(5000, -50); entry(6000, -10); entry(10000, -5)', aformat=
>> channel_layouts=mono,a
>> split [merge1], atrim= end_sample=883 [afir_in1]; [afir_in0][afir_in1]
>> afir, aformat=channel_layouts=mono, [merge1] amerge,
>> asplit[out0],showspectrum=s=1024x512[out1]"
>>
>> Note that your old patch didn't generate artifact.
>
> Artifacts are gone if you use bigger IR size, >2048.
>
> UPOLS should be rather trivial to understand and to implement.

Still happens at 8821 (44100 Hz with 0.1s delay):
./ffplay -f lavfi "aevalsrc='if(lt(t,1), if(n,0,1), sin(1000*t*t))',
aformat=channel_layouts=mono, asplit [afir_in0], fir
equalizer=zero_phase=on:gain_entry='entry(0, 0); entry(100, -4);
entry(1000, -30); entry(5000, -50); entry(6000, -10); entry(10000,
-5)':delay=0.1, aformat=channel_layo
uts=mono,asplit [merge1], atrim=end_sample=8821 [afir_in1];
[afir_in0][afir_in1] afir, aformat=channel_layouts=mono, [merge1]
amerge, asplit[out0],showspectrum=s=1024x5
12[out1]"
diff mbox

Patch

diff --git a/configure b/configure
index b3cb5b0..7fc7af4 100755
--- a/configure
+++ b/configure
@@ -3078,6 +3078,8 @@  unix_protocol_select="network"
 # filters
 afftfilt_filter_deps="avcodec"
 afftfilt_filter_select="fft"
+afirfilter_filter_deps="avcodec"
+afirfilter_filter_select="fft"
 amovie_filter_deps="avcodec avformat"
 aresample_filter_deps="swresample"
 ass_filter_deps="libass"
diff --git a/doc/filters.texi b/doc/filters.texi
index 119e747..ea343d1 100644
--- a/doc/filters.texi
+++ b/doc/filters.texi
@@ -878,6 +878,16 @@  afftfilt="1-clip((b/nb)*b,0,1)"
 @end example
 @end itemize
 
+@section afirfilter
+
+Apply an Arbitary Frequency Impulse Response filter.
+
+This filter uses second stream as FIR coefficients.
+If second stream holds single channel, it will be used
+for all input channels in first stream, otherwise
+number of channels in second stream must be same as
+number of channels in first stream.
+
 @anchor{aformat}
 @section aformat
 
diff --git a/libavfilter/Makefile b/libavfilter/Makefile
index 66c36e4..1a0f24b 100644
--- a/libavfilter/Makefile
+++ b/libavfilter/Makefile
@@ -38,6 +38,7 @@  OBJS-$(CONFIG_AEMPHASIS_FILTER)              += af_aemphasis.o
 OBJS-$(CONFIG_AEVAL_FILTER)                  += aeval.o
 OBJS-$(CONFIG_AFADE_FILTER)                  += af_afade.o
 OBJS-$(CONFIG_AFFTFILT_FILTER)               += af_afftfilt.o window_func.o
+OBJS-$(CONFIG_AFIRFILTER_FILTER)             += af_afirfilter.o
 OBJS-$(CONFIG_AFORMAT_FILTER)                += af_aformat.o
 OBJS-$(CONFIG_AGATE_FILTER)                  += af_agate.o
 OBJS-$(CONFIG_AINTERLEAVE_FILTER)            += f_interleave.o
diff --git a/libavfilter/af_afirfilter.c b/libavfilter/af_afirfilter.c
new file mode 100644
index 0000000..ef2488a
--- /dev/null
+++ b/libavfilter/af_afirfilter.c
@@ -0,0 +1,409 @@ 
+/*
+ * 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
+ */
+
+/**
+ * @file
+ * An arbitrary audio FIR filter
+ */
+
+#include "libavutil/audio_fifo.h"
+#include "libavutil/avassert.h"
+#include "libavutil/channel_layout.h"
+#include "libavutil/common.h"
+#include "libavutil/opt.h"
+#include "libavcodec/avfft.h"
+
+#include "audio.h"
+#include "avfilter.h"
+#include "formats.h"
+#include "internal.h"
+
+typedef struct FIRContext {
+    const AVClass *class;
+
+    int n;
+    int eof_coeffs;
+    int have_coeffs;
+    int nb_taps;
+    int fft_length;
+    int nb_channels;
+    int one2many;
+
+    FFTContext *fft, *ifft;
+    FFTComplex **fft_data;
+    FFTComplex **fft_coef;
+
+    AVAudioFifo *fifo[2];
+    AVFrame *in[2];
+    AVFrame *buffer;
+    int64_t pts;
+    int hop_size;
+    int start, end;
+} FIRContext;
+
+static int fir_filter(FIRContext *s, AVFilterLink *outlink)
+{
+    AVFilterContext *ctx = outlink->src;
+    int start = s->start, end = s->end;
+    int ret = 0, n, ch, j, k;
+    int nb_samples;
+    AVFrame *out;
+
+    nb_samples = FFMIN(s->fft_length, av_audio_fifo_size(s->fifo[0]));
+
+    s->in[0] = ff_get_audio_buffer(ctx->inputs[0], nb_samples);
+    if (!s->in[0])
+        return AVERROR(ENOMEM);
+
+    av_audio_fifo_peek(s->fifo[0], (void **)s->in[0]->extended_data, nb_samples);
+
+    for (ch = 0; ch < outlink->channels; ch++) {
+        const float *src = (float *)s->in[0]->extended_data[ch];
+        float *buf = (float *)s->buffer->extended_data[ch];
+        FFTComplex *fft_data = s->fft_data[ch];
+        FFTComplex *fft_coef = s->fft_coef[ch];
+
+        memset(fft_data, 0, sizeof(*fft_data) * s->fft_length);
+        for (n = 0; n < nb_samples; n++) {
+            fft_data[n].re = src[n];
+            fft_data[n].im = 0;
+        }
+
+        av_fft_permute(s->fft, fft_data);
+        av_fft_calc(s->fft, fft_data);
+
+        fft_data[0].re *= fft_coef[0].re;
+        fft_data[0].im *= fft_coef[0].im;
+        for (n = 1; n < s->fft_length; n++) {
+            const float re = fft_data[n].re;
+            const float im = fft_data[n].im;
+
+            fft_data[n].re = re * fft_coef[n].re - im * fft_coef[n].im;
+            fft_data[n].im = re * fft_coef[n].im + im * fft_coef[n].re;
+        }
+
+        av_fft_permute(s->ifft, fft_data);
+        av_fft_calc(s->ifft, fft_data);
+
+        start = s->start;
+        end = s->end;
+        k = end;
+
+        for (n = 0, j = start; j < k && n < s->fft_length; n++, j++) {
+            buf[j] = fft_data[n].re;
+        }
+
+        for (; n < s->fft_length; n++, j++) {
+            buf[j] = fft_data[n].re;
+        }
+
+        start += s->hop_size;
+        end = j;
+    }
+
+    s->start = start;
+    s->end   = end;
+
+    if (start >= nb_samples) {
+        float *dst, *buf;
+
+        start -= nb_samples;
+        end   -= nb_samples;
+
+        s->start = start;
+        s->end = end;
+
+        out = ff_get_audio_buffer(outlink, nb_samples);
+        if (!out)
+            return AVERROR(ENOMEM);
+
+        out->pts = s->pts;
+        s->pts += nb_samples;
+
+        for (ch = 0; ch < s->nb_channels; ch++) {
+            dst = (float *)out->extended_data[ch];
+            buf = (float *)s->buffer->extended_data[ch];
+
+            for (n = 0; n < nb_samples; n++)
+                dst[n] = buf[n];
+            memmove(buf, buf + nb_samples, nb_samples * 4);
+        }
+
+        ret = ff_filter_frame(outlink, out);
+    }
+
+    av_audio_fifo_drain(s->fifo[0], FFMIN(nb_samples, s->hop_size));
+    av_frame_free(&s->in[0]);
+
+    return ret;
+}
+
+static int convert_coeffs(AVFilterContext *ctx)
+{
+    FIRContext *s = ctx->priv;
+    int ch, n;
+
+    s->nb_taps = av_audio_fifo_size(s->fifo[1]);
+    if (s->nb_taps > 32768) {
+        av_log(ctx, AV_LOG_ERROR, "Too big number of taps: %d > 32768.\n", s->nb_taps);
+        return AVERROR(EINVAL);
+    }
+
+    for (n = 1; (1 << n) < s->nb_taps; n++);
+    s->n = n + 2;
+    s->fft_length = 1 << s->n;
+
+    for (ch = 0; ch < ctx->inputs[0]->channels; ch++) {
+        s->fft_data[ch] = av_calloc(s->fft_length, sizeof(**s->fft_data));
+        if (!s->fft_data[ch])
+            return AVERROR(ENOMEM);
+    }
+
+    for (ch = 0; ch < ctx->inputs[1]->channels; ch++) {
+        s->fft_coef[ch] = av_calloc(s->fft_length, sizeof(**s->fft_coef));
+        if (!s->fft_coef[ch])
+            return AVERROR(ENOMEM);
+    }
+
+    s->hop_size = s->fft_length - s->nb_taps + 1;
+    if (s->hop_size <= 0) {
+        av_log(ctx, AV_LOG_ERROR, "Too big number of taps.\n");
+        return AVERROR(EINVAL);
+    }
+
+    s->buffer = ff_get_audio_buffer(ctx->inputs[0], s->fft_length * 2);
+    if (!s->buffer)
+        return AVERROR(ENOMEM);
+
+    s->fft  = av_fft_init(s->n, 0);
+    s->ifft = av_fft_init(s->n, 1);
+    if (!s->fft || !s->ifft)
+        return AVERROR(ENOMEM);
+
+    s->in[1] = ff_get_audio_buffer(ctx->inputs[1], s->nb_taps);
+    if (!s->in[1])
+        return AVERROR(ENOMEM);
+
+    av_audio_fifo_read(s->fifo[1], (void **)s->in[1]->extended_data, s->nb_taps);
+    for (ch = 0; ch < ctx->inputs[1]->channels; ch++) {
+        FFTComplex *fft_coef = s->fft_coef[ch];
+        const float *re = (const float *)s->in[1]->extended_data[!s->one2many * ch];
+        const float scale = 1.f / s->fft_length;
+        const int offset = (s->fft_length - s->nb_taps);
+
+        memset(fft_coef, 0, sizeof(*fft_coef) * s->fft_length);
+        for (n = 0; n < s->nb_taps; n++) {
+            fft_coef[n + offset].re = re[n] * scale;
+        }
+        av_fft_permute(s->fft, fft_coef);
+        av_fft_calc(s->fft, fft_coef);
+    }
+
+    av_frame_free(&s->in[1]);
+    s->have_coeffs = 1;
+
+    return 0;
+}
+
+static int read_coeffs(AVFilterLink *link, AVFrame *frame)
+{
+    AVFilterContext *ctx = link->dst;
+    FIRContext *s = ctx->priv;
+
+    av_audio_fifo_write(s->fifo[1], (void **)frame->extended_data,
+                        frame->nb_samples);
+    av_frame_free(&frame);
+
+    return 0;
+}
+
+static int filter_frame(AVFilterLink *link, AVFrame *frame)
+{
+    AVFilterContext *ctx = link->dst;
+    FIRContext *s = ctx->priv;
+    AVFilterLink *outlink = ctx->outputs[0];
+    int ret = 0;
+
+    av_audio_fifo_write(s->fifo[0], (void **)frame->extended_data,
+                        frame->nb_samples);
+    av_frame_free(&frame);
+
+    if (!s->have_coeffs && s->eof_coeffs) {
+        ret = convert_coeffs(ctx);
+        if (ret < 0)
+            return ret;
+    }
+
+    if (s->have_coeffs) {
+        while (av_audio_fifo_size(s->fifo[0]) >= s->fft_length) {
+            ret = fir_filter(s, outlink);
+            if (ret < 0)
+                break;
+        }
+    }
+    return ret;
+}
+
+static int request_frame(AVFilterLink *outlink)
+{
+    AVFilterContext *ctx = outlink->src;
+    FIRContext *s = ctx->priv;
+    int ret;
+
+    if (!s->eof_coeffs) {
+        ret = ff_request_frame(ctx->inputs[1]);
+        if (ret == AVERROR_EOF) {
+            s->eof_coeffs = 1;
+            ret = 0;
+        }
+        return ret;
+    }
+    ret = ff_request_frame(ctx->inputs[0]);
+    if (ret == AVERROR_EOF && s->have_coeffs) {
+        while (av_audio_fifo_size(s->fifo[0]) > 0) {
+            ret = fir_filter(s, outlink);
+            if (ret < 0)
+                return ret;
+        }
+        ret = AVERROR_EOF;
+    }
+    return ret;
+}
+
+static int query_formats(AVFilterContext *ctx)
+{
+    AVFilterFormats *formats;
+    AVFilterChannelLayouts *layouts = NULL;
+    static const enum AVSampleFormat sample_fmts[] = {
+        AV_SAMPLE_FMT_FLTP,
+        AV_SAMPLE_FMT_NONE
+    };
+    int ret, i;
+
+    layouts = ff_all_channel_counts();
+    if ((ret = ff_channel_layouts_ref(layouts, &ctx->outputs[0]->in_channel_layouts)) < 0)
+        return ret;
+
+    for (i = 0; i < 2; i++) {
+        layouts = ff_all_channel_counts();
+        if ((ret = ff_channel_layouts_ref(layouts, &ctx->inputs[i]->out_channel_layouts)) < 0)
+            return ret;
+    }
+
+    formats = ff_make_format_list(sample_fmts);
+    if ((ret = ff_set_common_formats(ctx, formats)) < 0)
+        return ret;
+
+    formats = ff_all_samplerates();
+    return ff_set_common_samplerates(ctx, formats);
+}
+
+static int config_output(AVFilterLink *outlink)
+{
+    AVFilterContext *ctx = outlink->src;
+    FIRContext *s = ctx->priv;
+
+    if (ctx->inputs[0]->channels != ctx->inputs[1]->channels &&
+        ctx->inputs[1]->channels != 1) {
+        av_log(ctx, AV_LOG_ERROR,
+               "Second input must have same number of channels as first input or "
+               "exactly 1 channel.\n");
+        return AVERROR(EINVAL);
+    }
+
+    s->one2many = ctx->inputs[1]->channels == 1;
+    outlink->sample_rate = ctx->inputs[0]->sample_rate;
+    outlink->time_base   = ctx->inputs[0]->time_base;
+    outlink->channel_layout = ctx->inputs[0]->channel_layout;
+    outlink->channels = ctx->inputs[0]->channels;
+
+    s->fifo[0] = av_audio_fifo_alloc(ctx->inputs[0]->format, ctx->inputs[0]->channels, 1024);
+    s->fifo[1] = av_audio_fifo_alloc(ctx->inputs[1]->format, ctx->inputs[1]->channels, 1024);
+    if (!s->fifo[0] || !s->fifo[1])
+        return AVERROR(ENOMEM);
+
+    s->fft_data = av_calloc(outlink->channels, sizeof(*s->fft_data));
+    s->fft_coef = av_calloc(ctx->inputs[1]->channels, sizeof(*s->fft_coef));
+    if (!s->fft_data || !s->fft_coef)
+        return AVERROR(ENOMEM);
+    s->nb_channels = outlink->channels;
+
+    return 0;
+}
+
+static av_cold void uninit(AVFilterContext *ctx)
+{
+    FIRContext *s = ctx->priv;
+    int ch;
+
+    for (ch = 0; ch < s->nb_channels; ch++) {
+        if (s->fft_data)
+            av_freep(&s->fft_data[ch]);
+    }
+    av_freep(&s->fft_data);
+
+    for (ch = 0; ch < s->nb_channels; ch++) {
+        if (s->fft_coef)
+            av_freep(&s->fft_coef[ch]);
+    }
+    av_freep(&s->fft_coef);
+
+    av_fft_end(s->fft);
+    av_fft_end(s->ifft);
+
+    av_frame_free(&s->in[0]);
+    av_frame_free(&s->in[1]);
+
+    av_audio_fifo_free(s->fifo[0]);
+    av_audio_fifo_free(s->fifo[1]);
+}
+
+static const AVFilterPad afirfilter_inputs[] = {
+    {
+        .name           = "main",
+        .type           = AVMEDIA_TYPE_AUDIO,
+        .filter_frame   = filter_frame,
+    },{
+        .name           = "coefficients",
+        .type           = AVMEDIA_TYPE_AUDIO,
+        .filter_frame   = read_coeffs,
+    },
+    { NULL }
+};
+
+static const AVFilterPad afirfilter_outputs[] = {
+    {
+        .name          = "default",
+        .type          = AVMEDIA_TYPE_AUDIO,
+        .config_props  = config_output,
+        .request_frame = request_frame,
+    },
+    { NULL }
+};
+
+AVFilter ff_af_afirfilter = {
+    .name           = "afirfilter",
+    .description    = NULL_IF_CONFIG_SMALL("Apply Finite Impulse Response filter with supplied coefficients in 2nd stream."),
+    .priv_size      = sizeof(FIRContext),
+    .query_formats  = query_formats,
+    .uninit         = uninit,
+    .inputs         = afirfilter_inputs,
+    .outputs        = afirfilter_outputs,
+};
diff --git a/libavfilter/allfilters.c b/libavfilter/allfilters.c
index 8fb87eb..8bfe1ae 100644
--- a/libavfilter/allfilters.c
+++ b/libavfilter/allfilters.c
@@ -50,6 +50,7 @@  static void register_all(void)
     REGISTER_FILTER(AEVAL,          aeval,          af);
     REGISTER_FILTER(AFADE,          afade,          af);
     REGISTER_FILTER(AFFTFILT,       afftfilt,       af);
+    REGISTER_FILTER(AFIRFILTER,     afirfilter,     af);
     REGISTER_FILTER(AFORMAT,        aformat,        af);
     REGISTER_FILTER(AGATE,          agate,          af);
     REGISTER_FILTER(AINTERLEAVE,    ainterleave,    af);