[FFmpeg-devel] [PATCH] libavfilter/af_ambisonic.c Added File for Ambisonic Filter
Paul B Mahol
onemda at gmail.com
Sat Mar 11 14:27:19 EET 2017
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
>
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