ffmpeg/libavfilter/aeval.c

479 lines
16 KiB
C

/*
* Copyright (c) 2011 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
* eval audio source
*/
#include "libavutil/avstring.h"
#include "libavutil/channel_layout.h"
#include "libavutil/eval.h"
#include "libavutil/opt.h"
#include "libavutil/parseutils.h"
#include "avfilter.h"
#include "audio.h"
#include "filters.h"
#include "internal.h"
static const char * const var_names[] = {
"ch", ///< the value of the current channel
"n", ///< number of frame
"nb_in_channels",
"nb_out_channels",
"t", ///< timestamp expressed in seconds
"s", ///< sample rate
NULL
};
enum var_name {
VAR_CH,
VAR_N,
VAR_NB_IN_CHANNELS,
VAR_NB_OUT_CHANNELS,
VAR_T,
VAR_S,
VAR_VARS_NB
};
typedef struct EvalContext {
const AVClass *class;
char *sample_rate_str;
int sample_rate;
int64_t chlayout;
char *chlayout_str;
int nb_channels; ///< number of output channels
int nb_in_channels; ///< number of input channels
int same_chlayout; ///< set output as input channel layout
int64_t pts;
AVExpr **expr;
char *exprs;
int nb_samples; ///< number of samples per requested frame
int64_t duration;
uint64_t n;
double var_values[VAR_VARS_NB];
double *channel_values;
int64_t out_channel_layout;
} EvalContext;
static double val(void *priv, double ch)
{
EvalContext *eval = priv;
return eval->channel_values[FFMIN((int)ch, eval->nb_in_channels-1)];
}
static double (* const aeval_func1[])(void *, double) = { val, NULL };
static const char * const aeval_func1_names[] = { "val", NULL };
#define OFFSET(x) offsetof(EvalContext, x)
#define FLAGS AV_OPT_FLAG_AUDIO_PARAM|AV_OPT_FLAG_FILTERING_PARAM
static const AVOption aevalsrc_options[]= {
{ "exprs", "set the '|'-separated list of channels expressions", OFFSET(exprs), AV_OPT_TYPE_STRING, {.str = NULL}, .flags = FLAGS },
{ "nb_samples", "set the number of samples per requested frame", OFFSET(nb_samples), AV_OPT_TYPE_INT, {.i64 = 1024}, 0, INT_MAX, FLAGS },
{ "n", "set the number of samples per requested frame", OFFSET(nb_samples), AV_OPT_TYPE_INT, {.i64 = 1024}, 0, INT_MAX, FLAGS },
{ "sample_rate", "set the sample rate", OFFSET(sample_rate_str), AV_OPT_TYPE_STRING, {.str = "44100"}, 0, 0, FLAGS },
{ "s", "set the sample rate", OFFSET(sample_rate_str), AV_OPT_TYPE_STRING, {.str = "44100"}, 0, 0, FLAGS },
{ "duration", "set audio duration", OFFSET(duration), AV_OPT_TYPE_DURATION, {.i64 = -1}, -1, INT64_MAX, FLAGS },
{ "d", "set audio duration", OFFSET(duration), AV_OPT_TYPE_DURATION, {.i64 = -1}, -1, INT64_MAX, FLAGS },
{ "channel_layout", "set channel layout", OFFSET(chlayout_str), AV_OPT_TYPE_STRING, {.str = NULL}, 0, 0, FLAGS },
{ "c", "set channel layout", OFFSET(chlayout_str), AV_OPT_TYPE_STRING, {.str = NULL}, 0, 0, FLAGS },
{ NULL }
};
AVFILTER_DEFINE_CLASS(aevalsrc);
static int parse_channel_expressions(AVFilterContext *ctx,
int expected_nb_channels)
{
EvalContext *eval = ctx->priv;
char *args1 = av_strdup(eval->exprs);
char *expr, *last_expr = NULL, *buf;
double (* const *func1)(void *, double) = NULL;
const char * const *func1_names = NULL;
int i, ret = 0;
if (!args1)
return AVERROR(ENOMEM);
if (!eval->exprs) {
av_log(ctx, AV_LOG_ERROR, "Channels expressions list is empty\n");
return AVERROR(EINVAL);
}
if (!strcmp(ctx->filter->name, "aeval")) {
func1 = aeval_func1;
func1_names = aeval_func1_names;
}
#define ADD_EXPRESSION(expr_) do { \
ret = av_dynarray_add_nofree(&eval->expr, \
&eval->nb_channels, NULL); \
if (ret < 0) \
goto end; \
eval->expr[eval->nb_channels-1] = NULL; \
ret = av_expr_parse(&eval->expr[eval->nb_channels - 1], expr_, \
var_names, func1_names, func1, \
NULL, NULL, 0, ctx); \
if (ret < 0) \
goto end; \
} while (0)
/* reset expressions */
for (i = 0; i < eval->nb_channels; i++) {
av_expr_free(eval->expr[i]);
eval->expr[i] = NULL;
}
av_freep(&eval->expr);
eval->nb_channels = 0;
buf = args1;
while (expr = av_strtok(buf, "|", &buf)) {
ADD_EXPRESSION(expr);
last_expr = expr;
}
if (expected_nb_channels > eval->nb_channels)
for (i = eval->nb_channels; i < expected_nb_channels; i++)
ADD_EXPRESSION(last_expr);
if (expected_nb_channels > 0 && eval->nb_channels != expected_nb_channels) {
av_log(ctx, AV_LOG_ERROR,
"Mismatch between the specified number of channel expressions '%d' "
"and the number of expected output channels '%d' for the specified channel layout\n",
eval->nb_channels, expected_nb_channels);
ret = AVERROR(EINVAL);
goto end;
}
end:
av_free(args1);
return ret;
}
static av_cold int init(AVFilterContext *ctx)
{
EvalContext *eval = ctx->priv;
int ret = 0;
if (eval->chlayout_str) {
if (!strcmp(eval->chlayout_str, "same") && !strcmp(ctx->filter->name, "aeval")) {
eval->same_chlayout = 1;
} else {
ret = ff_parse_channel_layout(&eval->chlayout, NULL, eval->chlayout_str, ctx);
if (ret < 0)
return ret;
ret = parse_channel_expressions(ctx, av_get_channel_layout_nb_channels(eval->chlayout));
if (ret < 0)
return ret;
}
} else {
/* guess channel layout from nb expressions/channels */
if ((ret = parse_channel_expressions(ctx, -1)) < 0)
return ret;
eval->chlayout = av_get_default_channel_layout(eval->nb_channels);
if (!eval->chlayout && eval->nb_channels <= 0) {
av_log(ctx, AV_LOG_ERROR, "Invalid number of channels '%d' provided\n",
eval->nb_channels);
return AVERROR(EINVAL);
}
}
if (eval->sample_rate_str)
if ((ret = ff_parse_sample_rate(&eval->sample_rate, eval->sample_rate_str, ctx)))
return ret;
eval->n = 0;
return ret;
}
static av_cold void uninit(AVFilterContext *ctx)
{
EvalContext *eval = ctx->priv;
int i;
for (i = 0; i < eval->nb_channels; i++) {
av_expr_free(eval->expr[i]);
eval->expr[i] = NULL;
}
av_freep(&eval->expr);
av_freep(&eval->channel_values);
}
static int config_props(AVFilterLink *outlink)
{
EvalContext *eval = outlink->src->priv;
char buf[128];
outlink->time_base = (AVRational){1, eval->sample_rate};
outlink->sample_rate = eval->sample_rate;
eval->var_values[VAR_S] = eval->sample_rate;
eval->var_values[VAR_NB_IN_CHANNELS] = NAN;
eval->var_values[VAR_NB_OUT_CHANNELS] = outlink->channels;
av_get_channel_layout_string(buf, sizeof(buf), 0, eval->chlayout);
av_log(outlink->src, AV_LOG_VERBOSE,
"sample_rate:%d chlayout:%s duration:%"PRId64"\n",
eval->sample_rate, buf, eval->duration);
return 0;
}
static int query_formats(AVFilterContext *ctx)
{
EvalContext *eval = ctx->priv;
static const enum AVSampleFormat sample_fmts[] = { AV_SAMPLE_FMT_DBLP, AV_SAMPLE_FMT_NONE };
int64_t chlayouts[] = { eval->chlayout ? eval->chlayout : FF_COUNT2LAYOUT(eval->nb_channels) , -1 };
int sample_rates[] = { eval->sample_rate, -1 };
int ret;
ret = ff_set_common_formats_from_list(ctx, sample_fmts);
if (ret < 0)
return ret;
ret = ff_set_common_channel_layouts_from_list(ctx, chlayouts);
if (ret < 0)
return ret;
return ff_set_common_samplerates_from_list(ctx, sample_rates);
}
static int activate(AVFilterContext *ctx)
{
AVFilterLink *outlink = ctx->outputs[0];
EvalContext *eval = outlink->src->priv;
AVFrame *samplesref;
int i, j;
int64_t t = av_rescale(eval->n, AV_TIME_BASE, eval->sample_rate);
int nb_samples;
if (!ff_outlink_frame_wanted(outlink))
return FFERROR_NOT_READY;
if (eval->duration >= 0 && t >= eval->duration) {
ff_outlink_set_status(outlink, AVERROR_EOF, eval->pts);
return 0;
}
if (eval->duration >= 0) {
nb_samples = FFMIN(eval->nb_samples, av_rescale(eval->duration, eval->sample_rate, AV_TIME_BASE) - eval->pts);
if (!nb_samples) {
ff_outlink_set_status(outlink, AVERROR_EOF, eval->pts);
return 0;
}
} else {
nb_samples = eval->nb_samples;
}
samplesref = ff_get_audio_buffer(outlink, nb_samples);
if (!samplesref)
return AVERROR(ENOMEM);
/* evaluate expression for each single sample and for each channel */
for (i = 0; i < nb_samples; i++, eval->n++) {
eval->var_values[VAR_N] = eval->n;
eval->var_values[VAR_T] = eval->var_values[VAR_N] * (double)1/eval->sample_rate;
for (j = 0; j < eval->nb_channels; j++) {
*((double *) samplesref->extended_data[j] + i) =
av_expr_eval(eval->expr[j], eval->var_values, NULL);
}
}
samplesref->pts = eval->pts;
samplesref->sample_rate = eval->sample_rate;
eval->pts += nb_samples;
return ff_filter_frame(outlink, samplesref);
}
#if CONFIG_AEVALSRC_FILTER
static const AVFilterPad aevalsrc_outputs[] = {
{
.name = "default",
.type = AVMEDIA_TYPE_AUDIO,
.config_props = config_props,
},
};
const AVFilter ff_asrc_aevalsrc = {
.name = "aevalsrc",
.description = NULL_IF_CONFIG_SMALL("Generate an audio signal generated by an expression."),
.init = init,
.uninit = uninit,
.activate = activate,
.priv_size = sizeof(EvalContext),
.inputs = NULL,
FILTER_OUTPUTS(aevalsrc_outputs),
FILTER_QUERY_FUNC(query_formats),
.priv_class = &aevalsrc_class,
};
#endif /* CONFIG_AEVALSRC_FILTER */
#define OFFSET(x) offsetof(EvalContext, x)
#define FLAGS AV_OPT_FLAG_AUDIO_PARAM|AV_OPT_FLAG_FILTERING_PARAM
static const AVOption aeval_options[]= {
{ "exprs", "set the '|'-separated list of channels expressions", OFFSET(exprs), AV_OPT_TYPE_STRING, {.str = NULL}, .flags = FLAGS },
{ "channel_layout", "set channel layout", OFFSET(chlayout_str), AV_OPT_TYPE_STRING, {.str = NULL}, 0, 0, FLAGS },
{ "c", "set channel layout", OFFSET(chlayout_str), AV_OPT_TYPE_STRING, {.str = NULL}, 0, 0, FLAGS },
{ NULL }
};
AVFILTER_DEFINE_CLASS(aeval);
static int aeval_query_formats(AVFilterContext *ctx)
{
AVFilterChannelLayouts *layouts;
AVFilterLink *inlink = ctx->inputs[0];
AVFilterLink *outlink = ctx->outputs[0];
EvalContext *eval = ctx->priv;
static const enum AVSampleFormat sample_fmts[] = {
AV_SAMPLE_FMT_DBLP, AV_SAMPLE_FMT_NONE
};
int ret;
// inlink supports any channel layout
layouts = ff_all_channel_counts();
if ((ret = ff_channel_layouts_ref(layouts, &inlink->outcfg.channel_layouts)) < 0)
return ret;
if (eval->same_chlayout) {
if ((ret = ff_set_common_all_channel_counts(ctx)) < 0)
return ret;
} else {
// outlink supports only requested output channel layout
layouts = NULL;
if ((ret = ff_add_channel_layout(&layouts,
eval->out_channel_layout ? eval->out_channel_layout :
FF_COUNT2LAYOUT(eval->nb_channels))) < 0)
return ret;
if ((ret = ff_channel_layouts_ref(layouts, &outlink->incfg.channel_layouts)) < 0)
return ret;
}
if ((ret = ff_set_common_formats_from_list(ctx, sample_fmts)) < 0)
return ret;
return ff_set_common_all_samplerates(ctx);
}
static int aeval_config_output(AVFilterLink *outlink)
{
AVFilterContext *ctx = outlink->src;
EvalContext *eval = ctx->priv;
AVFilterLink *inlink = ctx->inputs[0];
int ret;
if (eval->same_chlayout) {
eval->chlayout = inlink->channel_layout;
if ((ret = parse_channel_expressions(ctx, inlink->channels)) < 0)
return ret;
}
eval->n = 0;
eval->nb_in_channels = eval->var_values[VAR_NB_IN_CHANNELS] = inlink->channels;
eval->var_values[VAR_NB_OUT_CHANNELS] = outlink->channels;
eval->var_values[VAR_S] = inlink->sample_rate;
eval->var_values[VAR_T] = NAN;
eval->channel_values = av_realloc_f(eval->channel_values,
inlink->channels, sizeof(*eval->channel_values));
if (!eval->channel_values)
return AVERROR(ENOMEM);
return 0;
}
static int filter_frame(AVFilterLink *inlink, AVFrame *in)
{
EvalContext *eval = inlink->dst->priv;
AVFilterLink *outlink = inlink->dst->outputs[0];
int nb_samples = in->nb_samples;
AVFrame *out;
double t0;
int i, j;
out = ff_get_audio_buffer(outlink, nb_samples);
if (!out) {
av_frame_free(&in);
return AVERROR(ENOMEM);
}
av_frame_copy_props(out, in);
t0 = TS2T(in->pts, inlink->time_base);
/* evaluate expression for each single sample and for each channel */
for (i = 0; i < nb_samples; i++, eval->n++) {
eval->var_values[VAR_N] = eval->n;
eval->var_values[VAR_T] = t0 + i * (double)1/inlink->sample_rate;
for (j = 0; j < inlink->channels; j++)
eval->channel_values[j] = *((double *) in->extended_data[j] + i);
for (j = 0; j < outlink->channels; j++) {
eval->var_values[VAR_CH] = j;
*((double *) out->extended_data[j] + i) =
av_expr_eval(eval->expr[j], eval->var_values, eval);
}
}
av_frame_free(&in);
return ff_filter_frame(outlink, out);
}
#if CONFIG_AEVAL_FILTER
static const AVFilterPad aeval_inputs[] = {
{
.name = "default",
.type = AVMEDIA_TYPE_AUDIO,
.filter_frame = filter_frame,
},
};
static const AVFilterPad aeval_outputs[] = {
{
.name = "default",
.type = AVMEDIA_TYPE_AUDIO,
.config_props = aeval_config_output,
},
};
const AVFilter ff_af_aeval = {
.name = "aeval",
.description = NULL_IF_CONFIG_SMALL("Filter audio signal according to a specified expression."),
.init = init,
.uninit = uninit,
.priv_size = sizeof(EvalContext),
FILTER_INPUTS(aeval_inputs),
FILTER_OUTPUTS(aeval_outputs),
FILTER_QUERY_FUNC(aeval_query_formats),
.priv_class = &aeval_class,
.flags = AVFILTER_FLAG_SUPPORT_TIMELINE_GENERIC,
};
#endif /* CONFIG_AEVAL_FILTER */