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mirror of https://github.com/FFmpeg/FFmpeg.git synced 2024-11-26 19:01:44 +02:00

aevalsrc: add duration option

This commit is contained in:
Stefano Sabatini 2011-12-02 15:33:15 +01:00
parent ba8410cb44
commit 6c26fe8b5a
3 changed files with 33 additions and 2 deletions

View File

@ -405,6 +405,16 @@ The description of the accepted options follows.
@table @option
@item duration, d
Set the minimum duration of the sourced audio. See the function
@code{av_parse_time()} for the accepted format.
Note that the resulting duration may be greater than the specified
duration, as the generated audio is always cut at the end of a
complete frame.
If not specified, or the expressed duration is negative, the audio is
supposed to be generated forever.
@item nb_samples, n
Set the number of samples per channel per each output frame,
default to 1024.

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@ -28,6 +28,7 @@
#include "libavutil/avstring.h"
#include "libavutil/eval.h"
#include "libavutil/opt.h"
#include "libavutil/parseutils.h"
#include "avfilter.h"
#include "internal.h"
@ -55,6 +56,8 @@ typedef struct {
AVExpr *expr[8];
char *expr_str[8];
int nb_samples; ///< number of samples per requested frame
char *duration_str; ///< total duration of the generated audio
double duration;
uint64_t n;
double var_values[VAR_VARS_NB];
} EvalContext;
@ -66,6 +69,8 @@ static const AVOption eval_options[]= {
{ "n", "set the number of samples per requested frame", OFFSET(nb_samples), AV_OPT_TYPE_INT, {.dbl = 1024}, 0, INT_MAX },
{ "sample_rate", "set the sample rate", OFFSET(sample_rate_str), AV_OPT_TYPE_STRING, {.str = "44100"}, CHAR_MIN, CHAR_MAX },
{ "s", "set the sample rate", OFFSET(sample_rate_str), AV_OPT_TYPE_STRING, {.str = "44100"}, CHAR_MIN, CHAR_MAX },
{ "duration", "set audio duration", OFFSET(duration_str), AV_OPT_TYPE_STRING, {.str = NULL}, 0, 0 },
{ "d", "set audio duration", OFFSET(duration_str), AV_OPT_TYPE_STRING, {.str = NULL}, 0, 0 },
{NULL},
};
@ -127,6 +132,16 @@ static int init(AVFilterContext *ctx, const char *args, void *opaque)
if ((ret = ff_parse_sample_rate(&eval->sample_rate, eval->sample_rate_str, ctx)))
goto end;
eval->duration = -1;
if (eval->duration_str) {
int64_t us = -1;
if ((ret = av_parse_time(&us, eval->duration_str, 1)) < 0) {
av_log(ctx, AV_LOG_ERROR, "Invalid duration: '%s'\n", eval->duration_str);
goto end;
}
eval->duration = (double)us / 1000000;
}
eval->n = 0;
end:
@ -143,6 +158,7 @@ static void uninit(AVFilterContext *ctx)
av_expr_free(eval->expr[i]);
eval->expr[i] = NULL;
}
av_freep(&eval->duration_str);
av_freep(&eval->sample_rate_str);
}
@ -159,7 +175,8 @@ static int config_props(AVFilterLink *outlink)
av_get_channel_layout_string(buf, sizeof(buf), 0, eval->chlayout);
av_log(outlink->src, AV_LOG_INFO,
"sample_rate:%d chlayout:%s\n", eval->sample_rate, buf);
"sample_rate:%d chlayout:%s duration:%f\n",
eval->sample_rate, buf, eval->duration);
return 0;
}
@ -183,6 +200,10 @@ static int request_frame(AVFilterLink *outlink)
EvalContext *eval = outlink->src->priv;
AVFilterBufferRef *samplesref;
int i, j;
double t = eval->var_values[VAR_N] * (double)1/eval->sample_rate;
if (eval->duration >= 0 && t > eval->duration)
return AVERROR_EOF;
samplesref = avfilter_get_audio_buffer(outlink, AV_PERM_WRITE, eval->nb_samples);

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@ -30,7 +30,7 @@
#define LIBAVFILTER_VERSION_MAJOR 2
#define LIBAVFILTER_VERSION_MINOR 50
#define LIBAVFILTER_VERSION_MICRO 0
#define LIBAVFILTER_VERSION_MICRO 1
#define LIBAVFILTER_VERSION_INT AV_VERSION_INT(LIBAVFILTER_VERSION_MAJOR, \
LIBAVFILTER_VERSION_MINOR, \