/*
* Copyright (c) 2011 Nicolas George <nicolas.george@normalesup.org>
*
* 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 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 merging filter
*/
#include "libswresample/swresample.h" // only for SWR_CH_MAX
#include "avfilter.h"
#include "audio.h"
#include "internal.h"
#define QUEUE_SIZE 16
typedef struct {
int nb_in_ch[2]; /**< number of channels for each input */
int route[SWR_CH_MAX]; /**< channels routing, see copy_samples */
int bps;
struct amerge_queue {
AVFilterBufferRef *buf[QUEUE_SIZE];
int nb_buf, nb_samples, pos;
} queue[2];
} AMergeContext;
static av_cold void uninit(AVFilterContext *ctx)
{
AMergeContext *am = ctx->priv;
int i, j;
for (i = 0; i < 2; i++)
for (j = 0; j < am->queue[i].nb_buf; j++)
avfilter_unref_buffer(am->queue[i].buf[j]);
}
static int query_formats(AVFilterContext *ctx)
{
AMergeContext *am = ctx->priv;
int64_t inlayout[2], outlayout;
AVFilterFormats *formats;
AVFilterChannelLayouts *layouts;
int i;
for (i = 0; i < 2; i++) {
if (!ctx->inputs[i]->in_channel_layouts ||
!ctx->inputs[i]->in_channel_layouts->nb_channel_layouts) {
av_log(ctx, AV_LOG_ERROR,
"No channel layout for input %d\n", i + 1);
return AVERROR(EINVAL);
}
inlayout[i] = ctx->inputs[i]->in_channel_layouts->channel_layouts[0];
if (ctx->inputs[i]->in_channel_layouts->nb_channel_layouts > 1) {
char buf[256];
av_get_channel_layout_string(buf, sizeof(buf), 0, inlayout[i]);
av_log(ctx, AV_LOG_INFO, "Using \"%s\" for input %d\n", buf, i + 1);
}
am->nb_in_ch[i] = av_get_channel_layout_nb_channels(inlayout[i]);
}
if (am->nb_in_ch[0] + am->nb_in_ch[1] > SWR_CH_MAX) {
av_log(ctx, AV_LOG_ERROR, "Too many channels (max %d)\n", SWR_CH_MAX);
return AVERROR(EINVAL);
}
if (inlayout[0] & inlayout[1]) {
av_log(ctx, AV_LOG_WARNING,
"Inputs overlap: output layout will be meaningless\n");
for (i = 0; i < am->nb_in_ch[0] + am->nb_in_ch[1]; i++)
am->route[i] = i;
outlayout = av_get_default_channel_layout(am->nb_in_ch[0] +
am->nb_in_ch[1]);
if (!outlayout)
outlayout = ((int64_t)1 << (am->nb_in_ch[0] + am->nb_in_ch[1])) - 1;
} else {
int *route[2] = { am->route, am->route + am->nb_in_ch[0] };
int c, out_ch_number = 0;
outlayout = inlayout[0] | inlayout[1];
for (c = 0; c < 64; c++)
for (i = 0; i < 2; i++)
if ((inlayout[i] >> c) & 1)
*(route[i]++) = out_ch_number++;
}
formats = avfilter_make_format_list(ff_packed_sample_fmts);
avfilter_set_common_sample_formats(ctx, formats);
for (i = 0; i < 2; i++) {
layouts = NULL;
ff_add_channel_layout(&layouts, inlayout[i]);
ff_channel_layouts_ref(layouts, &ctx->inputs[i]->out_channel_layouts);
}
layouts = NULL;
ff_add_channel_layout(&layouts, outlayout);
ff_channel_layouts_ref(layouts, &ctx->outputs[0]->in_channel_layouts);
ff_set_common_samplerates(ctx, ff_all_samplerates());
return 0;
}
static int config_output(AVFilterLink *outlink)
{
AVFilterContext *ctx = outlink->src;
AMergeContext *am = ctx->priv;
int64_t layout;
char name[3][256];
int i;
if (ctx->inputs[0]->sample_rate != ctx->inputs[1]->sample_rate) {
av_log(ctx, AV_LOG_ERROR,
"Inputs must have the same sample rate "
"(%"PRIi64" vs %"PRIi64")\n",
ctx->inputs[0]->sample_rate, ctx->inputs[1]->sample_rate);
return AVERROR(EINVAL);
}
am->bps = av_get_bytes_per_sample(ctx->outputs[0]->format);
outlink->sample_rate = ctx->inputs[0]->sample_rate;
outlink->time_base = ctx->inputs[0]->time_base;
for (i = 0; i < 3; i++) {
layout = (i < 2 ? ctx->inputs[i] : ctx->outputs[0])->channel_layout;
av_get_channel_layout_string(name[i], sizeof(name[i]), -1, layout);
}
av_log(ctx, AV_LOG_INFO,
"in1:%s + in2:%s -> out:%s\n", name[0], name[1], name[2]);
return 0;
}
static int request_frame(AVFilterLink *outlink)
{
AVFilterContext *ctx = outlink->src;
AMergeContext *am = ctx->priv;
int i, ret;
for (i = 0; i < 2; i++)
if (!am->queue[i].nb_samples)
if ((ret = avfilter_request_frame(ctx->inputs[i])) < 0)
return ret;
return 0;
}
/**
* Copy samples from two input streams to one output stream.
* @param nb_in_ch number of channels in each input stream
* @param route routing values;
* input channel i goes to output channel route[i];
* i < nb_in_ch[0] are the channels from the first output;
* i >= nb_in_ch[0] are the channels from the second output
* @param ins pointer to the samples of each inputs, in packed format;
* will be left at the end of the copied samples
* @param outs pointer to the samples of the output, in packet format;
* must point to a buffer big enough;
* will be left at the end of the copied samples
* @param ns number of samples to copy
* @param bps bytes per sample
*/
static inline void copy_samples(int nb_in_ch[2], int *route, uint8_t *ins[2],
uint8_t **outs, int ns, int bps)
{
int *route_cur;
int i, c;
while (ns--) {
route_cur = route;
for (i = 0; i < 2; i++) {
for (c = 0; c < nb_in_ch[i]; c++) {
memcpy((*outs) + bps * *(route_cur++), ins[i], bps);
ins[i] += bps;
}
}
*outs += (nb_in_ch[0] + nb_in_ch[1]) * bps;
}
}
static void filter_samples(AVFilterLink *inlink, AVFilterBufferRef *insamples)
{
AVFilterContext *ctx = inlink->dst;
AMergeContext *am = ctx->priv;
AVFilterLink *const outlink = ctx->outputs[0];
int input_number = inlink == ctx->inputs[1];
struct amerge_queue *inq = &am->queue[input_number];
int nb_samples, ns, i;
AVFilterBufferRef *outbuf, **inbuf[2];
uint8_t *ins[2], *outs;
if (inq->nb_buf == QUEUE_SIZE) {
av_log(ctx, AV_LOG_ERROR, "Packet queue overflow; dropped\n");
avfilter_unref_buffer(insamples);
return;
}
inq->buf[inq->nb_buf++] = avfilter_ref_buffer(insamples, AV_PERM_READ |
AV_PERM_PRESERVE);
inq->nb_samples += insamples->audio->nb_samples;
avfilter_unref_buffer(insamples);
if (!am->queue[!input_number].nb_samples)
return;
nb_samples = FFMIN(am->queue[0].nb_samples,
am->queue[1].nb_samples);
outbuf = ff_get_audio_buffer(ctx->outputs[0], AV_PERM_WRITE,
nb_samples);
outs = outbuf->data[0];
for (i = 0; i < 2; i++) {
inbuf[i] = am->queue[i].buf;
ins[i] = (*inbuf[i])->data[0] +
am->queue[i].pos * am->nb_in_ch[i] * am->bps;
}
outbuf->pts = (*inbuf[0])->pts == AV_NOPTS_VALUE ? AV_NOPTS_VALUE :
(*inbuf[0])->pts +
av_rescale_q(am->queue[0].pos,
(AVRational){ 1, ctx->inputs[0]->sample_rate },
ctx->outputs[0]->time_base);
avfilter_copy_buffer_ref_props(outbuf, *inbuf[0]);
outbuf->audio->nb_samples = nb_samples;
outbuf->audio->channel_layout = outlink->channel_layout;
while (nb_samples) {
ns = nb_samples;
for (i = 0; i < 2; i++)
ns = FFMIN(ns, (*inbuf[i])->audio->nb_samples - am->queue[i].pos);
/* Unroll the most common sample formats: speed +~350% for the loop,
+~13% overall (including two common decoders) */
switch (am->bps) {
case 1:
copy_samples(am->nb_in_ch, am->route, ins, &outs, ns, 1);
break;
case 2:
copy_samples(am->nb_in_ch, am->route, ins, &outs, ns, 2);
break;
case 4:
copy_samples(am->nb_in_ch, am->route, ins, &outs, ns, 4);
break;
default:
copy_samples(am->nb_in_ch, am->route, ins, &outs, ns, am->bps);
break;
}
nb_samples -= ns;
for (i = 0; i < 2; i++) {
am->queue[i].nb_samples -= ns;
am->queue[i].pos += ns;
if (am->queue[i].pos == (*inbuf[i])->audio->nb_samples) {
am->queue[i].pos = 0;
avfilter_unref_buffer(*inbuf[i]);
*inbuf[i] = NULL;
inbuf[i]++;
ins[i] = *inbuf[i] ? (*inbuf[i])->data[0] : NULL;
}
}
}
for (i = 0; i < 2; i++) {
int nbufused = inbuf[i] - am->queue[i].buf;
if (nbufused) {
am->queue[i].nb_buf -= nbufused;
memmove(am->queue[i].buf, inbuf[i],
am->queue[i].nb_buf * sizeof(**inbuf));
}
}
ff_filter_samples(ctx->outputs[0], outbuf);
}
AVFilter avfilter_af_amerge = {
.name = "amerge",
.description = NULL_IF_CONFIG_SMALL("Merge two audio streams into "
"a single multi-channel stream."),
.priv_size = sizeof(AMergeContext),
.uninit = uninit,
.query_formats = query_formats,
.inputs = (const AVFilterPad[]) {
{ .name = "in1",
.type = AVMEDIA_TYPE_AUDIO,
.filter_samples = filter_samples,
.min_perms = AV_PERM_READ, },
{ .name = "in2",
.type = AVMEDIA_TYPE_AUDIO,
.filter_samples = filter_samples,
.min_perms = AV_PERM_READ, },
{ .name = NULL }
},
.outputs = (const AVFilterPad[]) {
{ .name = "default",
.type = AVMEDIA_TYPE_AUDIO,
.config_props = config_output,
.request_frame = request_frame, },
{ .name = NULL }
},
};