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/*
* Copyright (c) 2012 Stefano Sabatini
*
* 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
* audio to video multimedia filter
*/
#include "libavutil/audioconvert.h"
#include "libavutil/opt.h"
#include "libavutil/parseutils.h"
#include "avfilter.h"
#include "formats.h"
#include "audio.h"
#include "video.h"
#include "internal.h"
typedef struct {
const AVClass *class;
int w, h;
char *rate_str;
AVRational rate;
int buf_idx;
AVFilterBufferRef *outpicref;
int req_fullfilled;
int n;
int sample_count_mod;
} ShowWavesContext;
#define OFFSET(x) offsetof(ShowWavesContext, x)
static const AVOption showwaves_options[] = {
{ "rate", "set video rate", OFFSET(rate_str), AV_OPT_TYPE_STRING, {.str = NULL}, 0, 0 },
{ "r", "set video rate", OFFSET(rate_str), AV_OPT_TYPE_STRING, {.str = NULL}, 0, 0 },
{ "size", "set video size", OFFSET(w), AV_OPT_TYPE_IMAGE_SIZE, {.str = "600x240"}, 0, 0 },
{ "s", "set video size", OFFSET(w), AV_OPT_TYPE_IMAGE_SIZE, {.str = "600x240"}, 0, 0 },
{ "n", "set how many samples to show in the same point", OFFSET(n), AV_OPT_TYPE_INT, {.dbl = 0}, 0, INT_MAX},
{ NULL },
};
AVFILTER_DEFINE_CLASS(showwaves);
static av_cold int init(AVFilterContext *ctx, const char *args)
{
ShowWavesContext *showwaves = ctx->priv;
int err;
showwaves->class = &showwaves_class;
av_opt_set_defaults(showwaves);
showwaves->buf_idx = 0;
if ((err = av_set_options_string(showwaves, args, "=", ":")) < 0) {
av_log(ctx, AV_LOG_ERROR, "Error parsing options string: '%s'\n", args);
return err;
}
return 0;
}
static av_cold void uninit(AVFilterContext *ctx)
{
ShowWavesContext *showwaves = ctx->priv;
av_freep(&showwaves->rate_str);
avfilter_unref_bufferp(&showwaves->outpicref);
}
static int query_formats(AVFilterContext *ctx)
{
AVFilterFormats *formats = NULL;
AVFilterChannelLayouts *layouts = NULL;
AVFilterLink *inlink = ctx->inputs[0];
AVFilterLink *outlink = ctx->outputs[0];
static const enum AVSampleFormat sample_fmts[] = { AV_SAMPLE_FMT_S16, -1 };
static const enum PixelFormat pix_fmts[] = { PIX_FMT_GRAY8, -1 };
/* set input audio formats */
formats = ff_make_format_list(sample_fmts);
if (!formats)
return AVERROR(ENOMEM);
ff_formats_ref(formats, &inlink->out_formats);
layouts = ff_all_channel_layouts();
if (!layouts)
return AVERROR(ENOMEM);
ff_channel_layouts_ref(layouts, &inlink->out_channel_layouts);
formats = ff_all_samplerates();
if (!formats)
return AVERROR(ENOMEM);
ff_formats_ref(formats, &inlink->out_samplerates);
/* set output video format */
formats = ff_make_format_list(pix_fmts);
if (!formats)
return AVERROR(ENOMEM);
ff_formats_ref(formats, &outlink->in_formats);
return 0;
}
static int config_output(AVFilterLink *outlink)
{
AVFilterContext *ctx = outlink->src;
AVFilterLink *inlink = ctx->inputs[0];
ShowWavesContext *showwaves = ctx->priv;
int err;
if (showwaves->n && showwaves->rate_str) {
av_log(ctx, AV_LOG_ERROR, "Options 'n' and 'rate' cannot be set at the same time\n");
return AVERROR(EINVAL);
}
if (!showwaves->n) {
if (!showwaves->rate_str)
showwaves->rate = (AVRational){25,1}; /* set default value */
else if ((err = av_parse_video_rate(&showwaves->rate, showwaves->rate_str)) < 0) {
av_log(ctx, AV_LOG_ERROR, "Invalid frame rate: '%s'\n", showwaves->rate_str);
return err;
}
showwaves->n = FFMAX(1, ((double)inlink->sample_rate / (showwaves->w * av_q2d(showwaves->rate))) + 0.5);
}
outlink->w = showwaves->w;
outlink->h = showwaves->h;
outlink->sample_aspect_ratio = (AVRational){1,1};
outlink->frame_rate = av_div_q((AVRational){inlink->sample_rate,showwaves->n},
(AVRational){showwaves->w,1});
av_log(ctx, AV_LOG_VERBOSE, "s:%dx%d r:%f n:%d\n",
showwaves->w, showwaves->h, av_q2d(outlink->frame_rate), showwaves->n);
return 0;
}
inline static void push_frame(AVFilterLink *outlink)
{
ShowWavesContext *showwaves = outlink->src->priv;
ff_start_frame(outlink, showwaves->outpicref);
ff_draw_slice(outlink, 0, outlink->h, 1);
ff_end_frame(outlink);
showwaves->req_fullfilled = 1;
showwaves->outpicref = NULL;
showwaves->buf_idx = 0;
}
static int request_frame(AVFilterLink *outlink)
{
ShowWavesContext *showwaves = outlink->src->priv;
AVFilterLink *inlink = outlink->src->inputs[0];
int ret;
showwaves->req_fullfilled = 0;
do {
ret = ff_request_frame(inlink);
} while (!showwaves->req_fullfilled && ret >= 0);
if (ret == AVERROR_EOF && showwaves->outpicref)
push_frame(outlink);
return ret;
}
#define MAX_INT16 ((1<<15) -1)
static int filter_samples(AVFilterLink *inlink, AVFilterBufferRef *insamples)
{
AVFilterContext *ctx = inlink->dst;
AVFilterLink *outlink = ctx->outputs[0];
ShowWavesContext *showwaves = ctx->priv;
const int nb_samples = insamples->audio->nb_samples;
AVFilterBufferRef *outpicref = showwaves->outpicref;
int linesize = outpicref ? outpicref->linesize[0] : 0;
int16_t *p = (int16_t *)insamples->data[0];
int nb_channels = av_get_channel_layout_nb_channels(insamples->audio->channel_layout);
int i, j, h;
const int n = showwaves->n;
const int x = 255 / (nb_channels * n); /* multiplication factor, pre-computed to avoid in-loop divisions */
/* draw data in the buffer */
for (i = 0; i < nb_samples; i++) {
if (showwaves->buf_idx == 0 && showwaves->sample_count_mod == 0) {
showwaves->outpicref = outpicref =
ff_get_video_buffer(outlink, AV_PERM_WRITE|AV_PERM_ALIGN,
outlink->w, outlink->h);
outpicref->video->w = outlink->w;
outpicref->video->h = outlink->h;
outpicref->pts = insamples->pts +
av_rescale_q((p - (int16_t *)insamples->data[0]) / nb_channels,
(AVRational){ 1, inlink->sample_rate },
outlink->time_base);
linesize = outpicref->linesize[0];
memset(outpicref->data[0], 0, showwaves->h*linesize);
}
for (j = 0; j < nb_channels; j++) {
h = showwaves->h/2 - av_rescale(*p++, showwaves->h/2, MAX_INT16);
if (h >= 0 && h < outlink->h)
*(outpicref->data[0] + showwaves->buf_idx + h * linesize) += x;
}
showwaves->sample_count_mod++;
if (showwaves->sample_count_mod == n) {
showwaves->sample_count_mod = 0;
showwaves->buf_idx++;
}
if (showwaves->buf_idx == showwaves->w)
push_frame(outlink);
}
avfilter_unref_buffer(insamples);
return 0;
}
AVFilter avfilter_avf_showwaves = {
.name = "showwaves",
.description = NULL_IF_CONFIG_SMALL("Convert input audio to a video output."),
.init = init,
.uninit = uninit,
.query_formats = query_formats,
.priv_size = sizeof(ShowWavesContext),
.inputs = (const AVFilterPad[]) {
{
.name = "default",
.type = AVMEDIA_TYPE_AUDIO,
.filter_samples = filter_samples,
.min_perms = AV_PERM_READ,
},
{ .name = NULL }
},
.outputs = (const AVFilterPad[]) {
{
.name = "default",
.type = AVMEDIA_TYPE_VIDEO,
.config_props = config_output,
.request_frame = request_frame,
},
{ .name = NULL }
},
};
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