lavfi/vf_fps: allow to set the rounding method.

By default, fps selects frames near PTS 0, 0.5, 1.5, 2.5, etc.
With round=down, it selects the frames near PTS 0, 1, 2, 3, etc.
This commit is contained in:
Nicolas George 2012-10-25 17:58:08 +02:00
parent cc72d52dc1
commit 77a72d3485
2 changed files with 12 additions and 2 deletions

View File

@ -2186,6 +2186,9 @@ This filter accepts the following named parameters:
@item fps
Desired output framerate.
@item round
Rounding method. The default is @code{near}.
@end table
@section framestep

View File

@ -46,6 +46,7 @@ typedef struct FPSContext {
AVRational framerate; ///< target framerate
char *fps; ///< a string describing target framerate
int rounding; ///< AVRounding method for timestamps
/* statistics */
int frames_in; ///< number of frames on input
@ -59,6 +60,12 @@ typedef struct FPSContext {
#define F AV_OPT_FLAG_FILTERING_PARAM
static const AVOption fps_options[] = {
{ "fps", "A string describing desired output framerate", OFFSET(fps), AV_OPT_TYPE_STRING, { .str = "25" }, .flags = V|F },
{ "round", "set rounding method for timestamps", OFFSET(rounding), AV_OPT_TYPE_INT, { .i64 = AV_ROUND_NEAR_INF }, 0, 5, V|F, "round" },
{ "zero", "round towards 0", OFFSET(rounding), AV_OPT_TYPE_CONST, { .i64 = AV_ROUND_ZERO }, 0, 5, V|F, "round" },
{ "inf", "round away from 0", OFFSET(rounding), AV_OPT_TYPE_CONST, { .i64 = AV_ROUND_INF }, 0, 5, V|F, "round" },
{ "down", "round towards -infty", OFFSET(rounding), AV_OPT_TYPE_CONST, { .i64 = AV_ROUND_DOWN }, 0, 5, V|F, "round" },
{ "up", "round towards +infty", OFFSET(rounding), AV_OPT_TYPE_CONST, { .i64 = AV_ROUND_UP }, 0, 5, V|F, "round" },
{ "near", "round to nearest", OFFSET(rounding), AV_OPT_TYPE_CONST, { .i64 = AV_ROUND_NEAR_INF }, 0, 5, V|F, "round" },
{ NULL },
};
@ -206,8 +213,8 @@ static int end_frame(AVFilterLink *inlink)
}
/* number of output frames */
delta = av_rescale_q(buf->pts - s->pts, inlink->time_base,
outlink->time_base);
delta = av_rescale_q_rnd(buf->pts - s->pts, inlink->time_base,
outlink->time_base, s->rounding);
if (delta < 1) {
/* drop the frame and everything buffered except the first */