/*
*
* This file is part of Libav.
*
* Libav 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.
*
* Libav 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 Libav; 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/audioconvert.h"
#include "libavutil/avassert.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.
*/
AVFilterBufferRef **input_frames;
/**
* Temporary storage for data pointers, for assembling the output buffer.
*/
uint8_t **data;
} JoinContext;
/**
* To avoid copying the data from input buffers, this filter creates
* a custom output buffer that stores references to all inputs and
* unrefs them on free.
*/
typedef struct JoinBufferPriv {
AVFilterBufferRef **in_buffers;
int nb_in_buffers;
} JoinBufferPriv;
#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 },
};
static const AVClass join_class = {
.class_name = "join filter",
.item_name = av_default_item_name,
.option = join_options,
.version = LIBAVUTIL_VERSION_INT,
};
static int filter_samples(AVFilterLink *link, AVFilterBufferRef *buf)
{
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] = buf;
return 0;
}
static int parse_maps(AVFilterContext *ctx)
{
JoinContext *s = ctx->priv;
char *cur = s->map;
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, ',');
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 int join_init(AVFilterContext *ctx, const char *args)
{
JoinContext *s = ctx->priv;
int ret, i;
s->class = &join_class;
av_opt_set_defaults(s);
if ((ret = av_set_options_string(s, args, "=", ":")) < 0)
return ret;
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);
ret = AVERROR(EINVAL);
goto fail;
}
s->nb_channels = av_get_channel_layout_nb_channels(s->channel_layout);
s->channels = av_mallocz(sizeof(*s->channels) * s->nb_channels);
s->data = av_mallocz(sizeof(*s->data) * s->nb_channels);
s->input_frames = av_mallocz(sizeof(*s->input_frames) * s->inputs);
if (!s->channels || !s->data || !s->input_frames) {
ret = AVERROR(ENOMEM);
goto fail;
}
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)
goto fail;
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_samples = filter_samples;
pad.needs_fifo = 1;
ff_insert_inpad(ctx, i, &pad);
}
fail:
av_opt_free(s);
return ret;
}
static 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);
avfilter_unref_bufferp(&s->input_frames[i]);
}
av_freep(&s->channels);
av_freep(&s->data);
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 void join_free_buffer(AVFilterBuffer *buf)
{
JoinBufferPriv *priv = buf->priv;
if (priv) {
int i;
for (i = 0; i < priv->nb_in_buffers; i++)
avfilter_unref_bufferp(&priv->in_buffers[i]);
av_freep(&priv->in_buffers);
av_freep(&buf->priv);
}
if (buf->extended_data != buf->data)
av_freep(&buf->extended_data);
av_freep(&buf);
}
static int join_request_frame(AVFilterLink *outlink)
{
AVFilterContext *ctx = outlink->src;
JoinContext *s = ctx->priv;
AVFilterBufferRef *buf;
JoinBufferPriv *priv;
int linesize = INT_MAX;
int perms = ~0;
int nb_samples = 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]->audio->nb_samples;
for (j = 1; !i && j < ctx->nb_inputs; j++)
ctx->inputs[j]->request_samples = nb_samples;
}
}
for (i = 0; i < s->nb_channels; i++) {
ChannelMap *ch = &s->channels[i];
AVFilterBufferRef *cur_buf = s->input_frames[ch->input];
s->data[i] = cur_buf->extended_data[ch->in_channel_idx];
linesize = FFMIN(linesize, cur_buf->linesize[0]);
perms &= cur_buf->perms;
}
av_assert0(nb_samples > 0);
buf = avfilter_get_audio_buffer_ref_from_arrays(s->data, linesize, perms,
nb_samples, outlink->format,
outlink->channel_layout);
if (!buf)
return AVERROR(ENOMEM);
buf->buf->free = join_free_buffer;
buf->pts = s->input_frames[0]->pts;
if (!(priv = av_mallocz(sizeof(*priv))))
goto fail;
if (!(priv->in_buffers = av_mallocz(sizeof(*priv->in_buffers) * ctx->nb_inputs)))
goto fail;
for (i = 0; i < ctx->nb_inputs; i++)
priv->in_buffers[i] = s->input_frames[i];
priv->nb_in_buffers = ctx->nb_inputs;
buf->buf->priv = priv;
ret = ff_filter_samples(outlink, buf);
memset(s->input_frames, 0, sizeof(*s->input_frames) * ctx->nb_inputs);
return ret;
fail:
avfilter_unref_buffer(buf);
if (priv)
av_freep(&priv->in_buffers);
av_freep(&priv);
return AVERROR(ENOMEM);
}
AVFilter avfilter_af_join = {
.name = "join",
.description = NULL_IF_CONFIG_SMALL("Join multiple audio streams into "
"multi-channel output"),
.priv_size = sizeof(JoinContext),
.init = join_init,
.uninit = join_uninit,
.query_formats = join_query_formats,
.inputs = NULL,
.outputs = (const AVFilterPad[]){{ .name = "default",
.type = AVMEDIA_TYPE_AUDIO,
.config_props = join_config_output,
.request_frame = join_request_frame, },
{ NULL }},
.priv_class = &join_class,
};