/*
* 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 join filter
*
* Join multiple audio inputs as different channels in
* a single output
*/
#include "libavutil/avassert.h"
#include "libavutil/channel_layout.h"
#include "libavutil/common.h"
#include "libavutil/opt.h"
#include "audio.h"
#include "avfilter.h"
#include "formats.h"
#include "internal.h"
typedef struct ChannelMap {
int input; ///< input stream index
int in_channel_idx; ///< index of in_channel in the input stream data
uint64_t in_channel; ///< layout describing the input channel
uint64_t out_channel; ///< layout describing the output channel
} ChannelMap;
typedef struct JoinContext {
const AVClass *class;
int inputs;
char *map;
char *channel_layout_str;
uint64_t channel_layout;
int nb_channels;
ChannelMap *channels;
/**
* Temporary storage for input frames, until we get one on each input.
*/
AVFrame **input_frames;
/**
* Temporary storage for buffer references, for assembling the output frame.
*/
AVBufferRef **buffers;
} JoinContext;
#define OFFSET(x) offsetof(JoinContext, x)
#define A AV_OPT_FLAG_AUDIO_PARAM
#define F AV_OPT_FLAG_FILTERING_PARAM
static const AVOption join_options[] = {
{ "inputs", "Number of input streams.", OFFSET(inputs), AV_OPT_TYPE_INT, { .i64 = 2 }, 1, INT_MAX, A|F },
{ "channel_layout", "Channel layout of the "
"output stream.", OFFSET(channel_layout_str), AV_OPT_TYPE_STRING, {.str = "stereo"}, 0, 0, A|F },
{ "map", "A comma-separated list of channels maps in the format "
"'input_stream.input_channel-output_channel.",
OFFSET(map), AV_OPT_TYPE_STRING, .flags = A|F },
{ NULL }
};
AVFILTER_DEFINE_CLASS(join);
static int filter_frame(AVFilterLink *link, AVFrame *frame)
{
AVFilterContext *ctx = link->dst;
JoinContext *s = ctx->priv;
int i;
for (i = 0; i < ctx->nb_inputs; i++)
if (link == ctx->inputs[i])
break;
av_assert0(i < ctx->nb_inputs);
av_assert0(!s->input_frames[i]);
s->input_frames[i] = frame;
return 0;
}
static int parse_maps(AVFilterContext *ctx)
{
JoinContext *s = ctx->priv;
char separator = '|';
char *cur = s->map;
#if FF_API_OLD_FILTER_OPTS
if (cur && strchr(cur, ',')) {
av_log(ctx, AV_LOG_WARNING, "This syntax is deprecated, use '|' to "
"separate the mappings.\n");
separator = ',';
}
#endif
while (cur && *cur) {
char *sep, *next, *p;
uint64_t in_channel = 0, out_channel = 0;
int input_idx, out_ch_idx, in_ch_idx;
next = strchr(cur, separator);
if (next)
*next++ = 0;
/* split the map into input and output parts */
if (!(sep = strchr(cur, '-'))) {
av_log(ctx, AV_LOG_ERROR, "Missing separator '-' in channel "
"map '%s'\n", cur);
return AVERROR(EINVAL);
}
*sep++ = 0;
#define PARSE_CHANNEL(str, var, inout) \
if (!(var = av_get_channel_layout(str))) { \
av_log(ctx, AV_LOG_ERROR, "Invalid " inout " channel: %s.\n", str);\
return AVERROR(EINVAL); \
} \
if (av_get_channel_layout_nb_channels(var) != 1) { \
av_log(ctx, AV_LOG_ERROR, "Channel map describes more than one " \
inout " channel.\n"); \
return AVERROR(EINVAL); \
}
/* parse output channel */
PARSE_CHANNEL(sep, out_channel, "output");
if (!(out_channel & s->channel_layout)) {
av_log(ctx, AV_LOG_ERROR, "Output channel '%s' is not present in "
"requested channel layout.\n", sep);
return AVERROR(EINVAL);
}
out_ch_idx = av_get_channel_layout_channel_index(s->channel_layout,
out_channel);
if (s->channels[out_ch_idx].input >= 0) {
av_log(ctx, AV_LOG_ERROR, "Multiple maps for output channel "
"'%s'.\n", sep);
return AVERROR(EINVAL);
}
/* parse input channel */
input_idx = strtol(cur, &cur, 0);
if (input_idx < 0 || input_idx >= s->inputs) {
av_log(ctx, AV_LOG_ERROR, "Invalid input stream index: %d.\n",
input_idx);
return AVERROR(EINVAL);
}
if (*cur)
cur++;
in_ch_idx = strtol(cur, &p, 0);
if (p == cur) {
/* channel specifier is not a number,
* try to parse as channel name */
PARSE_CHANNEL(cur, in_channel, "input");
}
s->channels[out_ch_idx].input = input_idx;
if (in_channel)
s->channels[out_ch_idx].in_channel = in_channel;
else
s->channels[out_ch_idx].in_channel_idx = in_ch_idx;
cur = next;
}
return 0;
}
static av_cold int join_init(AVFilterContext *ctx)
{
JoinContext *s = ctx->priv;
int ret, i;
if (!(s->channel_layout = av_get_channel_layout(s->channel_layout_str))) {
av_log(ctx, AV_LOG_ERROR, "Error parsing channel layout '%s'.\n",
s->channel_layout_str);
return AVERROR(EINVAL);
}
s->nb_channels = av_get_channel_layout_nb_channels(s->channel_layout);
s->channels = av_mallocz(sizeof(*s->channels) * s->nb_channels);
s->buffers = av_mallocz(sizeof(*s->buffers) * s->nb_channels);
s->input_frames = av_mallocz(sizeof(*s->input_frames) * s->inputs);
if (!s->channels || !s->buffers|| !s->input_frames)
return AVERROR(ENOMEM);
for (i = 0; i < s->nb_channels; i++) {
s->channels[i].out_channel = av_channel_layout_extract_channel(s->channel_layout, i);
s->channels[i].input = -1;
}
if ((ret = parse_maps(ctx)) < 0)
return ret;
for (i = 0; i < s->inputs; i++) {
char name[32];
AVFilterPad pad = { 0 };
snprintf(name, sizeof(name), "input%d", i);
pad.type = AVMEDIA_TYPE_AUDIO;
pad.name = av_strdup(name);
pad.filter_frame = filter_frame;
pad.needs_fifo = 1;
ff_insert_inpad(ctx, i, &pad);
}
return 0;
}
static av_cold void join_uninit(AVFilterContext *ctx)
{
JoinContext *s = ctx->priv;
int i;
for (i = 0; i < ctx->nb_inputs; i++) {
av_freep(&ctx->input_pads[i].name);
av_frame_free(&s->input_frames[i]);
}
av_freep(&s->channels);
av_freep(&s->buffers);
av_freep(&s->input_frames);
}
static int join_query_formats(AVFilterContext *ctx)
{
JoinContext *s = ctx->priv;
AVFilterChannelLayouts *layouts = NULL;
int i;
ff_add_channel_layout(&layouts, s->channel_layout);
ff_channel_layouts_ref(layouts, &ctx->outputs[0]->in_channel_layouts);
for (i = 0; i < ctx->nb_inputs; i++)
ff_channel_layouts_ref(ff_all_channel_layouts(),
&ctx->inputs[i]->out_channel_layouts);
ff_set_common_formats (ctx, ff_planar_sample_fmts());
ff_set_common_samplerates(ctx, ff_all_samplerates());
return 0;
}
static void guess_map_matching(AVFilterContext *ctx, ChannelMap *ch,
uint64_t *inputs)
{
int i;
for (i = 0; i < ctx->nb_inputs; i++) {
AVFilterLink *link = ctx->inputs[i];
if (ch->out_channel & link->channel_layout &&
!(ch->out_channel & inputs[i])) {
ch->input = i;
ch->in_channel = ch->out_channel;
inputs[i] |= ch->out_channel;
return;
}
}
}
static void guess_map_any(AVFilterContext *ctx, ChannelMap *ch,
uint64_t *inputs)
{
int i;
for (i = 0; i < ctx->nb_inputs; i++) {
AVFilterLink *link = ctx->inputs[i];
if ((inputs[i] & link->channel_layout) != link->channel_layout) {
uint64_t unused = link->channel_layout & ~inputs[i];
ch->input = i;
ch->in_channel = av_channel_layout_extract_channel(unused, 0);
inputs[i] |= ch->in_channel;
return;
}
}
}
static int join_config_output(AVFilterLink *outlink)
{
AVFilterContext *ctx = outlink->src;
JoinContext *s = ctx->priv;
uint64_t *inputs; // nth element tracks which channels are used from nth input
int i, ret = 0;
/* initialize inputs to user-specified mappings */
if (!(inputs = av_mallocz(sizeof(*inputs) * ctx->nb_inputs)))
return AVERROR(ENOMEM);
for (i = 0; i < s->nb_channels; i++) {
ChannelMap *ch = &s->channels[i];
AVFilterLink *inlink;
if (ch->input < 0)
continue;
inlink = ctx->inputs[ch->input];
if (!ch->in_channel)
ch->in_channel = av_channel_layout_extract_channel(inlink->channel_layout,
ch->in_channel_idx);
if (!(ch->in_channel & inlink->channel_layout)) {
av_log(ctx, AV_LOG_ERROR, "Requested channel %s is not present in "
"input stream #%d.\n", av_get_channel_name(ch->in_channel),
ch->input);
ret = AVERROR(EINVAL);
goto fail;
}
inputs[ch->input] |= ch->in_channel;
}
/* guess channel maps when not explicitly defined */
/* first try unused matching channels */
for (i = 0; i < s->nb_channels; i++) {
ChannelMap *ch = &s->channels[i];
if (ch->input < 0)
guess_map_matching(ctx, ch, inputs);
}
/* if the above failed, try to find _any_ unused input channel */
for (i = 0; i < s->nb_channels; i++) {
ChannelMap *ch = &s->channels[i];
if (ch->input < 0)
guess_map_any(ctx, ch, inputs);
if (ch->input < 0) {
av_log(ctx, AV_LOG_ERROR, "Could not find input channel for "
"output channel '%s'.\n",
av_get_channel_name(ch->out_channel));
goto fail;
}
ch->in_channel_idx = av_get_channel_layout_channel_index(ctx->inputs[ch->input]->channel_layout,
ch->in_channel);
}
/* print mappings */
av_log(ctx, AV_LOG_VERBOSE, "mappings: ");
for (i = 0; i < s->nb_channels; i++) {
ChannelMap *ch = &s->channels[i];
av_log(ctx, AV_LOG_VERBOSE, "%d.%s => %s ", ch->input,
av_get_channel_name(ch->in_channel),
av_get_channel_name(ch->out_channel));
}
av_log(ctx, AV_LOG_VERBOSE, "\n");
for (i = 0; i < ctx->nb_inputs; i++) {
if (!inputs[i])
av_log(ctx, AV_LOG_WARNING, "No channels are used from input "
"stream %d.\n", i);
}
fail:
av_freep(&inputs);
return ret;
}
static int join_request_frame(AVFilterLink *outlink)
{
AVFilterContext *ctx = outlink->src;
JoinContext *s = ctx->priv;
AVFrame *frame;
int linesize = INT_MAX;
int nb_samples = 0;
int nb_buffers = 0;
int i, j, ret;
/* get a frame on each input */
for (i = 0; i < ctx->nb_inputs; i++) {
AVFilterLink *inlink = ctx->inputs[i];
if (!s->input_frames[i] &&
(ret = ff_request_frame(inlink)) < 0)
return ret;
/* request the same number of samples on all inputs */
if (i == 0) {
nb_samples = s->input_frames[0]->nb_samples;
for (j = 1; !i && j < ctx->nb_inputs; j++)
ctx->inputs[j]->request_samples = nb_samples;
}
}
/* setup the output frame */
frame = av_frame_alloc();
if (!frame)
return AVERROR(ENOMEM);
if (s->nb_channels > FF_ARRAY_ELEMS(frame->data)) {
frame->extended_data = av_mallocz(s->nb_channels *
sizeof(*frame->extended_data));
if (!frame->extended_data) {
ret = AVERROR(ENOMEM);
goto fail;
}
}
/* copy the data pointers */
for (i = 0; i < s->nb_channels; i++) {
ChannelMap *ch = &s->channels[i];
AVFrame *cur = s->input_frames[ch->input];
AVBufferRef *buf;
frame->extended_data[i] = cur->extended_data[ch->in_channel_idx];
linesize = FFMIN(linesize, cur->linesize[0]);
/* add the buffer where this plan is stored to the list if it's
* not already there */
buf = av_frame_get_plane_buffer(cur, ch->in_channel_idx);
if (!buf) {
ret = AVERROR(EINVAL);
goto fail;
}
for (j = 0; j < nb_buffers; j++)
if (s->buffers[j]->buffer == buf->buffer)
break;
if (j == i)
s->buffers[nb_buffers++] = buf;
}
/* create references to the buffers we copied to output */
if (nb_buffers > FF_ARRAY_ELEMS(frame->buf)) {
frame->nb_extended_buf = nb_buffers - FF_ARRAY_ELEMS(frame->buf);
frame->extended_buf = av_mallocz(sizeof(*frame->extended_buf) *
frame->nb_extended_buf);
if (!frame->extended_buf) {
frame->nb_extended_buf = 0;
ret = AVERROR(ENOMEM);
goto fail;
}
}
for (i = 0; i < FFMIN(FF_ARRAY_ELEMS(frame->buf), nb_buffers); i++) {
frame->buf[i] = av_buffer_ref(s->buffers[i]);
if (!frame->buf[i]) {
ret = AVERROR(ENOMEM);
goto fail;
}
}
for (i = 0; i < frame->nb_extended_buf; i++) {
frame->extended_buf[i] = av_buffer_ref(s->buffers[i +
FF_ARRAY_ELEMS(frame->buf)]);
if (!frame->extended_buf[i]) {
ret = AVERROR(ENOMEM);
goto fail;
}
}
frame->nb_samples = nb_samples;
frame->channel_layout = outlink->channel_layout;
av_frame_set_channels(frame, outlink->channels);
frame->format = outlink->format;
frame->sample_rate = outlink->sample_rate;
frame->pts = s->input_frames[0]->pts;
frame->linesize[0] = linesize;
if (frame->data != frame->extended_data) {
memcpy(frame->data, frame->extended_data, sizeof(*frame->data) *
FFMIN(FF_ARRAY_ELEMS(frame->data), s->nb_channels));
}
ret = ff_filter_frame(outlink, frame);
for (i = 0; i < ctx->nb_inputs; i++)
av_frame_free(&s->input_frames[i]);
return ret;
fail:
av_frame_free(&frame);
return ret;
}
static const AVFilterPad avfilter_af_join_outputs[] = {
{
.name = "default",
.type = AVMEDIA_TYPE_AUDIO,
.config_props = join_config_output,
.request_frame = join_request_frame,
},
{ NULL }
};
AVFilter ff_af_join = {
.name = "join",
.description = NULL_IF_CONFIG_SMALL("Join multiple audio streams into "
"multi-channel output."),
.priv_size = sizeof(JoinContext),
.priv_class = &join_class,
.init = join_init,
.uninit = join_uninit,
.query_formats = join_query_formats,
.inputs = NULL,
.outputs = avfilter_af_join_outputs,
.flags = AVFILTER_FLAG_DYNAMIC_INPUTS,
};