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|
/*
* filter graphs
* Copyright (c) 2008 Vitor Sessak
* Copyright (c) 2007 Bobby Bingham
*
* 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
*/
#include <string.h>
#include "libavutil/avassert.h"
#include "libavutil/channel_layout.h"
#include "libavutil/common.h"
#include "libavutil/log.h"
#include "avfilter.h"
#include "avfiltergraph.h"
#include "formats.h"
#include "internal.h"
static const AVClass filtergraph_class = {
.class_name = "AVFilterGraph",
.item_name = av_default_item_name,
.version = LIBAVUTIL_VERSION_INT,
};
AVFilterGraph *avfilter_graph_alloc(void)
{
AVFilterGraph *ret = av_mallocz(sizeof(*ret));
if (!ret)
return NULL;
ret->av_class = &filtergraph_class;
return ret;
}
void avfilter_graph_free(AVFilterGraph **graph)
{
if (!*graph)
return;
for (; (*graph)->nb_filters > 0; (*graph)->nb_filters--)
avfilter_free((*graph)->filters[(*graph)->nb_filters - 1]);
av_freep(&(*graph)->scale_sws_opts);
av_freep(&(*graph)->resample_lavr_opts);
av_freep(&(*graph)->filters);
av_freep(graph);
}
int avfilter_graph_add_filter(AVFilterGraph *graph, AVFilterContext *filter)
{
AVFilterContext **filters = av_realloc(graph->filters,
sizeof(*filters) * (graph->nb_filters + 1));
if (!filters)
return AVERROR(ENOMEM);
graph->filters = filters;
graph->filters[graph->nb_filters++] = filter;
return 0;
}
int avfilter_graph_create_filter(AVFilterContext **filt_ctx, AVFilter *filt,
const char *name, const char *args, void *opaque,
AVFilterGraph *graph_ctx)
{
int ret;
if ((ret = avfilter_open(filt_ctx, filt, name)) < 0)
goto fail;
if ((ret = avfilter_init_filter(*filt_ctx, args, opaque)) < 0)
goto fail;
if ((ret = avfilter_graph_add_filter(graph_ctx, *filt_ctx)) < 0)
goto fail;
return 0;
fail:
if (*filt_ctx)
avfilter_free(*filt_ctx);
*filt_ctx = NULL;
return ret;
}
/**
* Check for the validity of graph.
*
* A graph is considered valid if all its input and output pads are
* connected.
*
* @return 0 in case of success, a negative value otherwise
*/
static int graph_check_validity(AVFilterGraph *graph, AVClass *log_ctx)
{
AVFilterContext *filt;
int i, j;
for (i = 0; i < graph->nb_filters; i++) {
filt = graph->filters[i];
for (j = 0; j < filt->nb_inputs; j++) {
if (!filt->inputs[j] || !filt->inputs[j]->src) {
av_log(log_ctx, AV_LOG_ERROR,
"Input pad \"%s\" for the filter \"%s\" of type \"%s\" not connected to any source\n",
filt->input_pads[j].name, filt->name, filt->filter->name);
return AVERROR(EINVAL);
}
}
for (j = 0; j < filt->nb_outputs; j++) {
if (!filt->outputs[j] || !filt->outputs[j]->dst) {
av_log(log_ctx, AV_LOG_ERROR,
"Output pad \"%s\" for the filter \"%s\" of type \"%s\" not connected to any destination\n",
filt->output_pads[j].name, filt->name, filt->filter->name);
return AVERROR(EINVAL);
}
}
}
return 0;
}
/**
* Configure all the links of graphctx.
*
* @return 0 in case of success, a negative value otherwise
*/
static int graph_config_links(AVFilterGraph *graph, AVClass *log_ctx)
{
AVFilterContext *filt;
int i, ret;
for (i = 0; i < graph->nb_filters; i++) {
filt = graph->filters[i];
if (!filt->nb_outputs) {
if ((ret = avfilter_config_links(filt)))
return ret;
}
}
return 0;
}
AVFilterContext *avfilter_graph_get_filter(AVFilterGraph *graph, char *name)
{
int i;
for (i = 0; i < graph->nb_filters; i++)
if (graph->filters[i]->name && !strcmp(name, graph->filters[i]->name))
return graph->filters[i];
return NULL;
}
static int query_formats(AVFilterGraph *graph, AVClass *log_ctx)
{
int i, j, ret;
int scaler_count = 0, resampler_count = 0;
/* ask all the sub-filters for their supported media formats */
for (i = 0; i < graph->nb_filters; i++) {
if (graph->filters[i]->filter->query_formats)
graph->filters[i]->filter->query_formats(graph->filters[i]);
else
ff_default_query_formats(graph->filters[i]);
}
/* go through and merge as many format lists as possible */
for (i = 0; i < graph->nb_filters; i++) {
AVFilterContext *filter = graph->filters[i];
for (j = 0; j < filter->nb_inputs; j++) {
AVFilterLink *link = filter->inputs[j];
int convert_needed = 0;
if (!link)
continue;
if (link->in_formats != link->out_formats &&
!ff_merge_formats(link->in_formats,
link->out_formats))
convert_needed = 1;
if (link->type == AVMEDIA_TYPE_AUDIO) {
if (link->in_channel_layouts != link->out_channel_layouts &&
!ff_merge_channel_layouts(link->in_channel_layouts,
link->out_channel_layouts))
convert_needed = 1;
if (link->in_samplerates != link->out_samplerates &&
!ff_merge_samplerates(link->in_samplerates,
link->out_samplerates))
convert_needed = 1;
}
if (convert_needed) {
AVFilterContext *convert;
AVFilter *filter;
AVFilterLink *inlink, *outlink;
char scale_args[256];
char inst_name[30];
/* couldn't merge format lists. auto-insert conversion filter */
switch (link->type) {
case AVMEDIA_TYPE_VIDEO:
if (!(filter = avfilter_get_by_name("scale"))) {
av_log(log_ctx, AV_LOG_ERROR, "'scale' filter "
"not present, cannot convert pixel formats.\n");
return AVERROR(EINVAL);
}
snprintf(inst_name, sizeof(inst_name), "auto-inserted scaler %d",
scaler_count++);
snprintf(scale_args, sizeof(scale_args), "0:0:%s", graph->scale_sws_opts);
if ((ret = avfilter_graph_create_filter(&convert, filter,
inst_name, scale_args, NULL,
graph)) < 0)
return ret;
break;
case AVMEDIA_TYPE_AUDIO:
if (!(filter = avfilter_get_by_name("resample"))) {
av_log(log_ctx, AV_LOG_ERROR, "'resample' filter "
"not present, cannot convert audio formats.\n");
return AVERROR(EINVAL);
}
snprintf(inst_name, sizeof(inst_name), "auto-inserted resampler %d",
resampler_count++);
scale_args[0] = '\0';
if (graph->resample_lavr_opts)
snprintf(scale_args, sizeof(scale_args), "%s",
graph->resample_lavr_opts);
if ((ret = avfilter_graph_create_filter(&convert, filter,
inst_name, scale_args,
NULL, graph)) < 0)
return ret;
break;
default:
return AVERROR(EINVAL);
}
if ((ret = avfilter_insert_filter(link, convert, 0, 0)) < 0)
return ret;
convert->filter->query_formats(convert);
inlink = convert->inputs[0];
outlink = convert->outputs[0];
if (!ff_merge_formats( inlink->in_formats, inlink->out_formats) ||
!ff_merge_formats(outlink->in_formats, outlink->out_formats))
ret |= AVERROR(ENOSYS);
if (inlink->type == AVMEDIA_TYPE_AUDIO &&
(!ff_merge_samplerates(inlink->in_samplerates,
inlink->out_samplerates) ||
!ff_merge_channel_layouts(inlink->in_channel_layouts,
inlink->out_channel_layouts)))
ret |= AVERROR(ENOSYS);
if (outlink->type == AVMEDIA_TYPE_AUDIO &&
(!ff_merge_samplerates(outlink->in_samplerates,
outlink->out_samplerates) ||
!ff_merge_channel_layouts(outlink->in_channel_layouts,
outlink->out_channel_layouts)))
ret |= AVERROR(ENOSYS);
if (ret < 0) {
av_log(log_ctx, AV_LOG_ERROR,
"Impossible to convert between the formats supported by the filter "
"'%s' and the filter '%s'\n", link->src->name, link->dst->name);
return ret;
}
}
}
}
return 0;
}
static int pick_format(AVFilterLink *link)
{
if (!link || !link->in_formats)
return 0;
link->in_formats->format_count = 1;
link->format = link->in_formats->formats[0];
if (link->type == AVMEDIA_TYPE_AUDIO) {
if (!link->in_samplerates->format_count) {
av_log(link->src, AV_LOG_ERROR, "Cannot select sample rate for"
" the link between filters %s and %s.\n", link->src->name,
link->dst->name);
return AVERROR(EINVAL);
}
link->in_samplerates->format_count = 1;
link->sample_rate = link->in_samplerates->formats[0];
if (!link->in_channel_layouts->nb_channel_layouts) {
av_log(link->src, AV_LOG_ERROR, "Cannot select channel layout for"
"the link between filters %s and %s.\n", link->src->name,
link->dst->name);
return AVERROR(EINVAL);
}
link->in_channel_layouts->nb_channel_layouts = 1;
link->channel_layout = link->in_channel_layouts->channel_layouts[0];
}
ff_formats_unref(&link->in_formats);
ff_formats_unref(&link->out_formats);
ff_formats_unref(&link->in_samplerates);
ff_formats_unref(&link->out_samplerates);
ff_channel_layouts_unref(&link->in_channel_layouts);
ff_channel_layouts_unref(&link->out_channel_layouts);
return 0;
}
#define REDUCE_FORMATS(fmt_type, list_type, list, var, nb, add_format) \
do { \
for (i = 0; i < filter->nb_inputs; i++) { \
AVFilterLink *link = filter->inputs[i]; \
fmt_type fmt; \
\
if (!link->out_ ## list || link->out_ ## list->nb != 1) \
continue; \
fmt = link->out_ ## list->var[0]; \
\
for (j = 0; j < filter->nb_outputs; j++) { \
AVFilterLink *out_link = filter->outputs[j]; \
list_type *fmts; \
\
if (link->type != out_link->type || \
out_link->in_ ## list->nb == 1) \
continue; \
fmts = out_link->in_ ## list; \
\
if (!out_link->in_ ## list->nb) { \
add_format(&out_link->in_ ##list, fmt); \
break; \
} \
\
for (k = 0; k < out_link->in_ ## list->nb; k++) \
if (fmts->var[k] == fmt) { \
fmts->var[0] = fmt; \
fmts->nb = 1; \
ret = 1; \
break; \
} \
} \
} \
} while (0)
static int reduce_formats_on_filter(AVFilterContext *filter)
{
int i, j, k, ret = 0;
REDUCE_FORMATS(int, AVFilterFormats, formats, formats,
format_count, ff_add_format);
REDUCE_FORMATS(int, AVFilterFormats, samplerates, formats,
format_count, ff_add_format);
REDUCE_FORMATS(uint64_t, AVFilterChannelLayouts, channel_layouts,
channel_layouts, nb_channel_layouts, ff_add_channel_layout);
return ret;
}
static void reduce_formats(AVFilterGraph *graph)
{
int i, reduced;
do {
reduced = 0;
for (i = 0; i < graph->nb_filters; i++)
reduced |= reduce_formats_on_filter(graph->filters[i]);
} while (reduced);
}
static void swap_samplerates_on_filter(AVFilterContext *filter)
{
AVFilterLink *link = NULL;
int sample_rate;
int i, j;
for (i = 0; i < filter->nb_inputs; i++) {
link = filter->inputs[i];
if (link->type == AVMEDIA_TYPE_AUDIO &&
link->out_samplerates->format_count == 1)
break;
}
if (i == filter->nb_inputs)
return;
sample_rate = link->out_samplerates->formats[0];
for (i = 0; i < filter->nb_outputs; i++) {
AVFilterLink *outlink = filter->outputs[i];
int best_idx, best_diff = INT_MAX;
if (outlink->type != AVMEDIA_TYPE_AUDIO ||
outlink->in_samplerates->format_count < 2)
continue;
for (j = 0; j < outlink->in_samplerates->format_count; j++) {
int diff = abs(sample_rate - outlink->in_samplerates->formats[j]);
if (diff < best_diff) {
best_diff = diff;
best_idx = j;
}
}
FFSWAP(int, outlink->in_samplerates->formats[0],
outlink->in_samplerates->formats[best_idx]);
}
}
static void swap_samplerates(AVFilterGraph *graph)
{
int i;
for (i = 0; i < graph->nb_filters; i++)
swap_samplerates_on_filter(graph->filters[i]);
}
#define CH_CENTER_PAIR (AV_CH_FRONT_LEFT_OF_CENTER | AV_CH_FRONT_RIGHT_OF_CENTER)
#define CH_FRONT_PAIR (AV_CH_FRONT_LEFT | AV_CH_FRONT_RIGHT)
#define CH_STEREO_PAIR (AV_CH_STEREO_LEFT | AV_CH_STEREO_RIGHT)
#define CH_WIDE_PAIR (AV_CH_WIDE_LEFT | AV_CH_WIDE_RIGHT)
#define CH_SIDE_PAIR (AV_CH_SIDE_LEFT | AV_CH_SIDE_RIGHT)
#define CH_DIRECT_PAIR (AV_CH_SURROUND_DIRECT_LEFT | AV_CH_SURROUND_DIRECT_RIGHT)
#define CH_BACK_PAIR (AV_CH_BACK_LEFT | AV_CH_BACK_RIGHT)
/* allowable substitutions for channel pairs when comparing layouts,
* ordered by priority for both values */
static const uint64_t ch_subst[][2] = {
{ CH_FRONT_PAIR, CH_CENTER_PAIR },
{ CH_FRONT_PAIR, CH_WIDE_PAIR },
{ CH_FRONT_PAIR, AV_CH_FRONT_CENTER },
{ CH_CENTER_PAIR, CH_FRONT_PAIR },
{ CH_CENTER_PAIR, CH_WIDE_PAIR },
{ CH_CENTER_PAIR, AV_CH_FRONT_CENTER },
{ CH_WIDE_PAIR, CH_FRONT_PAIR },
{ CH_WIDE_PAIR, CH_CENTER_PAIR },
{ CH_WIDE_PAIR, AV_CH_FRONT_CENTER },
{ AV_CH_FRONT_CENTER, CH_FRONT_PAIR },
{ AV_CH_FRONT_CENTER, CH_CENTER_PAIR },
{ AV_CH_FRONT_CENTER, CH_WIDE_PAIR },
{ CH_SIDE_PAIR, CH_DIRECT_PAIR },
{ CH_SIDE_PAIR, CH_BACK_PAIR },
{ CH_SIDE_PAIR, AV_CH_BACK_CENTER },
{ CH_BACK_PAIR, CH_DIRECT_PAIR },
{ CH_BACK_PAIR, CH_SIDE_PAIR },
{ CH_BACK_PAIR, AV_CH_BACK_CENTER },
{ AV_CH_BACK_CENTER, CH_BACK_PAIR },
{ AV_CH_BACK_CENTER, CH_DIRECT_PAIR },
{ AV_CH_BACK_CENTER, CH_SIDE_PAIR },
};
static void swap_channel_layouts_on_filter(AVFilterContext *filter)
{
AVFilterLink *link = NULL;
int i, j, k;
for (i = 0; i < filter->nb_inputs; i++) {
link = filter->inputs[i];
if (link->type == AVMEDIA_TYPE_AUDIO &&
link->out_channel_layouts->nb_channel_layouts == 1)
break;
}
if (i == filter->nb_inputs)
return;
for (i = 0; i < filter->nb_outputs; i++) {
AVFilterLink *outlink = filter->outputs[i];
int best_idx = -1, best_score = INT_MIN, best_count_diff = INT_MAX;
if (outlink->type != AVMEDIA_TYPE_AUDIO ||
outlink->in_channel_layouts->nb_channel_layouts < 2)
continue;
for (j = 0; j < outlink->in_channel_layouts->nb_channel_layouts; j++) {
uint64_t in_chlayout = link->out_channel_layouts->channel_layouts[0];
uint64_t out_chlayout = outlink->in_channel_layouts->channel_layouts[j];
int in_channels = av_get_channel_layout_nb_channels(in_chlayout);
int out_channels = av_get_channel_layout_nb_channels(out_chlayout);
int count_diff = out_channels - in_channels;
int matched_channels, extra_channels;
int score = 0;
/* channel substitution */
for (k = 0; k < FF_ARRAY_ELEMS(ch_subst); k++) {
uint64_t cmp0 = ch_subst[k][0];
uint64_t cmp1 = ch_subst[k][1];
if (( in_chlayout & cmp0) && (!(out_chlayout & cmp0)) &&
(out_chlayout & cmp1) && (!( in_chlayout & cmp1))) {
in_chlayout &= ~cmp0;
out_chlayout &= ~cmp1;
/* add score for channel match, minus a deduction for
having to do the substitution */
score += 10 * av_get_channel_layout_nb_channels(cmp1) - 2;
}
}
/* no penalty for LFE channel mismatch */
if ( (in_chlayout & AV_CH_LOW_FREQUENCY) &&
(out_chlayout & AV_CH_LOW_FREQUENCY))
score += 10;
in_chlayout &= ~AV_CH_LOW_FREQUENCY;
out_chlayout &= ~AV_CH_LOW_FREQUENCY;
matched_channels = av_get_channel_layout_nb_channels(in_chlayout &
out_chlayout);
extra_channels = av_get_channel_layout_nb_channels(out_chlayout &
(~in_chlayout));
score += 10 * matched_channels - 5 * extra_channels;
if (score > best_score ||
(count_diff < best_count_diff && score == best_score)) {
best_score = score;
best_idx = j;
best_count_diff = count_diff;
}
}
av_assert0(best_idx >= 0);
FFSWAP(uint64_t, outlink->in_channel_layouts->channel_layouts[0],
outlink->in_channel_layouts->channel_layouts[best_idx]);
}
}
static void swap_channel_layouts(AVFilterGraph *graph)
{
int i;
for (i = 0; i < graph->nb_filters; i++)
swap_channel_layouts_on_filter(graph->filters[i]);
}
static void swap_sample_fmts_on_filter(AVFilterContext *filter)
{
AVFilterLink *link = NULL;
int format, bps;
int i, j;
for (i = 0; i < filter->nb_inputs; i++) {
link = filter->inputs[i];
if (link->type == AVMEDIA_TYPE_AUDIO &&
link->out_formats->format_count == 1)
break;
}
if (i == filter->nb_inputs)
return;
format = link->out_formats->formats[0];
bps = av_get_bytes_per_sample(format);
for (i = 0; i < filter->nb_outputs; i++) {
AVFilterLink *outlink = filter->outputs[i];
int best_idx = -1, best_score = INT_MIN;
if (outlink->type != AVMEDIA_TYPE_AUDIO ||
outlink->in_formats->format_count < 2)
continue;
for (j = 0; j < outlink->in_formats->format_count; j++) {
int out_format = outlink->in_formats->formats[j];
int out_bps = av_get_bytes_per_sample(out_format);
int score;
if (av_get_packed_sample_fmt(out_format) == format ||
av_get_planar_sample_fmt(out_format) == format) {
best_idx = j;
break;
}
/* for s32 and float prefer double to prevent loss of information */
if (bps == 4 && out_bps == 8) {
best_idx = j;
break;
}
/* prefer closest higher or equal bps */
score = -abs(out_bps - bps);
if (out_bps >= bps)
score += INT_MAX/2;
if (score > best_score) {
best_score = score;
best_idx = j;
}
}
av_assert0(best_idx >= 0);
FFSWAP(int, outlink->in_formats->formats[0],
outlink->in_formats->formats[best_idx]);
}
}
static void swap_sample_fmts(AVFilterGraph *graph)
{
int i;
for (i = 0; i < graph->nb_filters; i++)
swap_sample_fmts_on_filter(graph->filters[i]);
}
static int pick_formats(AVFilterGraph *graph)
{
int i, j, ret;
for (i = 0; i < graph->nb_filters; i++) {
AVFilterContext *filter = graph->filters[i];
for (j = 0; j < filter->nb_inputs; j++)
if ((ret = pick_format(filter->inputs[j])) < 0)
return ret;
for (j = 0; j < filter->nb_outputs; j++)
if ((ret = pick_format(filter->outputs[j])) < 0)
return ret;
}
return 0;
}
/**
* Configure the formats of all the links in the graph.
*/
static int graph_config_formats(AVFilterGraph *graph, AVClass *log_ctx)
{
int ret;
/* find supported formats from sub-filters, and merge along links */
if ((ret = query_formats(graph, log_ctx)) < 0)
return ret;
/* Once everything is merged, it's possible that we'll still have
* multiple valid media format choices. We try to minimize the amount
* of format conversion inside filters */
reduce_formats(graph);
/* for audio filters, ensure the best format, sample rate and channel layout
* is selected */
swap_sample_fmts(graph);
swap_samplerates(graph);
swap_channel_layouts(graph);
if ((ret = pick_formats(graph)) < 0)
return ret;
return 0;
}
static int graph_insert_fifos(AVFilterGraph *graph, AVClass *log_ctx)
{
AVFilterContext *f;
int i, j, ret;
int fifo_count = 0;
for (i = 0; i < graph->nb_filters; i++) {
f = graph->filters[i];
for (j = 0; j < f->nb_inputs; j++) {
AVFilterLink *link = f->inputs[j];
AVFilterContext *fifo_ctx;
AVFilter *fifo;
char name[32];
if (!link->dstpad->needs_fifo)
continue;
fifo = f->inputs[j]->type == AVMEDIA_TYPE_VIDEO ?
avfilter_get_by_name("fifo") :
avfilter_get_by_name("afifo");
snprintf(name, sizeof(name), "auto-inserted fifo %d", fifo_count++);
ret = avfilter_graph_create_filter(&fifo_ctx, fifo, name, NULL,
NULL, graph);
if (ret < 0)
return ret;
ret = avfilter_insert_filter(link, fifo_ctx, 0, 0);
if (ret < 0)
return ret;
}
}
return 0;
}
int avfilter_graph_config(AVFilterGraph *graphctx, void *log_ctx)
{
int ret;
if ((ret = graph_check_validity(graphctx, log_ctx)))
return ret;
if ((ret = graph_insert_fifos(graphctx, log_ctx)) < 0)
return ret;
if ((ret = graph_config_formats(graphctx, log_ctx)))
return ret;
if ((ret = graph_config_links(graphctx, log_ctx)))
return ret;
return 0;
}
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