[FFmpeg-devel] [PATCH] libavfilter/af_ambisonic.c Added File for Ambisonic Filter

Sanchit Sinha sanchit15083 at iiitd.ac.in
Sat Mar 11 15:26:21 EET 2017


On Sat, Mar 11, 2017 at 5:57 PM, Paul B Mahol <onemda at gmail.com> wrote:

> On 3/11/17, Sanchit Sinha <sanchit15083 at iiitd.ac.in> wrote:
> > Patch details:
> > File added avfilter/af_ambisonic.c
> > Entries made in avfilter/Makefile and avfilter/allfilters.c
> > Entry made in Changelog
>
> Learn not to top post.
>
> > From bb9915658d1089e36f5b3131ec5851a058a57c62 Mon Sep 17 00:00:00 2001
> > From: Sanchit Sinha <sanchit15083 at iiitd.ac.in>
> > Date: Sat, 11 Mar 2017 17:04:47 +0530
> > Subject: [PATCH] avfiler/af_ambisonic.c: file added
> avfilter/allfilters.c and
> >  Makefile: entry added Changelog: entry mentioned
> >
> > ---
> >  Changelog                  |   1 +
> >  libavfilter/Makefile       |   1 +
> >  libavfilter/af_ambisonic.c | 137 ++++++++++++++++++++++++++++++
> +++++++++++++++
> >  libavfilter/allfilters.c   |   1 +
> >  4 files changed, 140 insertions(+)
> >  create mode 100644 libavfilter/af_ambisonic.c
> >
> > diff --git a/Changelog b/Changelog
> > index 13628ca..b917ac2 100644
> > --- a/Changelog
> > +++ b/Changelog
> > @@ -26,6 +26,7 @@ version <next>:
> >  - native Opus encoder
> >  - ScreenPressor decoder
> >  - incomplete ClearVideo decoder
> > +- Ambisonic Decoder
> >
> >  version 3.2:
> >  - libopenmpt demuxer
> > diff --git a/libavfilter/Makefile b/libavfilter/Makefile
> > index 0ba1c74..16fd612 100644
> > --- a/libavfilter/Makefile
> > +++ b/libavfilter/Makefile
> > @@ -47,6 +47,7 @@ OBJS-$(CONFIG_ALOOP_FILTER)                  +=
> f_loop.o
> >  OBJS-$(CONFIG_AMERGE_FILTER)                 += af_amerge.o
> >  OBJS-$(CONFIG_AMETADATA_FILTER)              += f_metadata.o
> >  OBJS-$(CONFIG_AMIX_FILTER)                   += af_amix.o
> > +OBJS-$(CONFIG_AMBISONIC_FILTER)              += af_ambisonic.o
>
> B comes before I
>
> >  OBJS-$(CONFIG_ANEQUALIZER_FILTER)            += af_anequalizer.o
> >  OBJS-$(CONFIG_ANULL_FILTER)                  += af_anull.o
> >  OBJS-$(CONFIG_APAD_FILTER)                   += af_apad.o
> > diff --git a/libavfilter/af_ambisonic.c b/libavfilter/af_ambisonic.c
> > new file mode 100644
> > index 0000000..32f3c0c
> > --- /dev/null
> > +++ b/libavfilter/af_ambisonic.c
> > @@ -0,0 +1,137 @@
> > +/*
> > + * 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 <stdio.h>
> > +#include "libavutil/avstring.h"
> > +#include "libavutil/channel_layout.h"
> > +#include "libavutil/opt.h"
> > +#include "audio.h"
> > +#include "avfilter.h"
> > +#include "formats.h"
> > +#include <math.h>
> > +
> > +typedef struct AmbisonicContext {
> > +     const AVClass *class;
> > +     /*Not needed, if any new variables are to be used, this struct can
> be populated(f)*/
> > +
> > +} AmbisonicContext;
> > +
> > +#define OFFSET(x) offsetof(AmbisonicContext, x)
> > +
> > +static const AVOption ambisonic_options[] = {  //square will be an
> option
> > +{NULL}
> > +};
> > +
> > +AVFILTER_DEFINE_CLASS(ambisonic);
> > +static int query_formats(AVFilterContext *ctx)
> > +{
> > +     AVFilterFormats *formats = NULL;
> > +     AVFilterChannelLayouts *layout = NULL;
> > +     int ret;
> > +     if ((ret = ff_add_format     (&formats, AV_SAMPLE_FMT_FLTP   )) <
> 0 ||
> > +     (ret = ff_set_common_formats     (ctx    , formats )) < 0 ||
> > +     (ret = ff_add_channel_layout     (&layout , AV_CH_LAYOUT_4POINT0))
> < 0 ||
> > +     (ret = ff_set_common_channel_layouts (ctx    , layout   )) < 0)
> > +     return ret;
> > +     formats = ff_all_samplerates();
> > +     return ff_set_common_samplerates(ctx, formats);
> > +}
> > +static int filter_frame(AVFilterLink *inlink, AVFrame *in)
> > +{
> > +     AVFilterContext *ctx = inlink->dst;
> > +     AVFilterLink *outlink = ctx->outputs[0];
> > +     /*If variables used, this has to be created*/
> > +     // AmbisonicContext *s = ctx->priv;
> > +     // const float *src = (const float *)in->data[0];
> > +     // float *dst;
> > +     AVFrame *out;
> > +     int itr;
> > +     float *w,*x,*y;
> > +     float root8= sqrt(8);
> > +     float lf=0,lb=0,rb=0,rf=0;
> > +
> > +     if (av_frame_is_writable(in))
> > +     {
> > +             out = in;
> > +     }
> > +     else
> > +     {
>
> Code style is awful.
>
> > +             out = ff_get_audio_buffer(inlink, in->nb_samples);
> > +             if (!out)
> > +             {
>
> Please do not change code style of code you copied.
> Instead follow its style to the end.
>
> > +                     av_frame_free(&in);
> > +                     return AVERROR(ENOMEM);
> > +             }
> > +             av_frame_copy_props(out, in);
> > +     }
> > +
> > +     /*If planar samples are used, output must be put in dst*/
> > +     //dst = (float *)out->data[0];
>
> Remove those remnants.
>
> > +
> > +     w=(float *)in->extended_data[0];
> > +     x=(float *)in->extended_data[1];
> > +     y=(float *)in->extended_data[2];
> > +
> > +     for(itr=0;itr<in->nb_samples;itr++)
> > +     {
>
> For loops { comes in line above.
>
> > +             /*Float pointers to the samples*/
>
> Please remove this, maybe this is still hopeful for you, but
> I really hope not. If you still have problems with pointers I advise
> you to look at other projects.
>
> > +
> > +             lf = root8 * (2*(w[itr])+x[itr]+y[itr]);
> > +             lb = root8 * (2*(w[itr])-x[itr]+y[itr]);
> > +             rb = root8 * (2*(w[itr])-x[itr]-y[itr]);
> > +             rf = root8 * (2*(w[itr])+x[itr]-y[itr]);
> > +
> > +             out->extended_data[0][itr]= lf;
> > +             out->extended_data[1][itr]= lb;
> > +             out->extended_data[2][itr]= rb;
> > +             out->extended_data[3][itr]= rf;
>
> This is wrong. Must use similar pointers like what was done for
> in->extended_data.
>
> > +     }
> > +
> > +     if (out != in)
> > +     av_frame_free(&in);
>
> Wrong indentation.
>
> > +     return ff_filter_frame(outlink, out);
> > +}
> > +
> > +static const AVFilterPad inputs[] = {
> > +     {
> > +     .name    = "default",
>
> Indentation is wrong.
>
> > +     .type    = AVMEDIA_TYPE_AUDIO,
> > +     .filter_frame = filter_frame,
> > +     // .config_props = config_input,
>
> Remove commented out stuff.
>
> > +     },
> > +     { NULL }
> > +};
> > +
> > +static const AVFilterPad outputs[] = {
> > +     {
> > +     .name = "default",
> > +     .type = AVMEDIA_TYPE_AUDIO,
> > +     },
> > +     { NULL }
> > +};
> > +
> > +AVFilter ff_af_ambisonic = {
> > +     .name      = "ambisonic",
> > +     .description    = NULL_IF_CONFIG_SMALL("An ambisonic filter"),
> > +     .query_formats  = query_formats,
> > +     .priv_size    = sizeof(AmbisonicContext),
> > +     .priv_class  = &ambisonic_class,
> > +     // .uninit   = uninit,
>
> Remove commented out stuff.
>
> > +     .inputs  = inputs,
> > +     .outputs    = outputs,
> > +};
> > \ No newline at end of file
> > diff --git a/libavfilter/allfilters.c b/libavfilter/allfilters.c
> > index df1af8d..59aeb6d 100644
> > --- a/libavfilter/allfilters.c
> > +++ b/libavfilter/allfilters.c
> > @@ -56,6 +56,7 @@ static void register_all(void)
> >      REGISTER_FILTER(ALIMITER,       alimiter,       af);
> >      REGISTER_FILTER(ALLPASS,        allpass,        af);
> >      REGISTER_FILTER(ALOOP,          aloop,          af);
> > +    REGISTER_FILTER(AMBISONIC,      ambisonic,      af);
> >      REGISTER_FILTER(AMERGE,         amerge,         af);
> >      REGISTER_FILTER(AMETADATA,      ametadata,      af);
> >      REGISTER_FILTER(AMIX,           amix,           af);
> > --
> > 2.7.4
> >
> _______________________________________________
> ffmpeg-devel mailing list
> ffmpeg-devel at ffmpeg.org
> http://ffmpeg.org/mailman/listinfo/ffmpeg-devel
>



-- 
Sanchit Sinha
B.Tech- CSE
IIIT-Delhi
Roll-2015083
-------------- next part --------------
A non-text attachment was scrubbed...
Name: 0001-avfiler-af_ambisonic.c-sound-quality-improvement.patch
Type: text/x-patch
Size: 3363 bytes
Desc: not available
URL: <http://ffmpeg.org/pipermail/ffmpeg-devel/attachments/20170311/578dad2b/attachment.bin>


More information about the ffmpeg-devel mailing list