From e700d87b200fe618d99dcefa9b7e041ac7f5a931 Mon Sep 17 00:00:00 2001 From: Oleg <oafanasiev@gmail.com> Date: Sat, 29 Apr 2023 19:56:46 +0100 Subject: avfilter/setpts: add command support Add support for changing expr on the fly. Signed-off-by: Oleg <oafanasiev@gmail.com> --- libavfilter/setpts.c | 73 ++++++++++++++++++++++++++++++++++++++++------------ 1 file changed, 56 insertions(+), 17 deletions(-) (limited to 'libavfilter') diff --git a/libavfilter/setpts.c b/libavfilter/setpts.c index 7a5cd3ef78..6dade06e6a 100644 --- a/libavfilter/setpts.c +++ b/libavfilter/setpts.c @@ -63,6 +63,7 @@ static const char *const var_names[] = { "S", // Number of samples in the current frame "SR", // Audio sample rate "FR", ///< defined only for constant frame-rate video + "T_CHANGE", ///< time of first frame after latest command was applied NULL }; @@ -90,7 +91,8 @@ enum var_name { VAR_S, VAR_SR, VAR_FR, - VAR_VARS_NB + VAR_T_CHANGE, + VAR_VARS_NB, }; typedef struct SetPTSContext { @@ -120,6 +122,7 @@ static av_cold int init(AVFilterContext *ctx) setpts->var_values[VAR_PREV_OUTT] = NAN; setpts->var_values[VAR_STARTPTS] = NAN; setpts->var_values[VAR_STARTT] = NAN; + setpts->var_values[VAR_T_CHANGE] = NAN; return 0; } @@ -163,6 +166,9 @@ static double eval_pts(SetPTSContext *setpts, AVFilterLink *inlink, AVFrame *fra setpts->var_values[VAR_STARTPTS] = TS2D(pts); setpts->var_values[VAR_STARTT ] = TS2T(pts, inlink->time_base); } + if (isnan(setpts->var_values[VAR_T_CHANGE])) { + setpts->var_values[VAR_T_CHANGE] = TS2T(pts, inlink->time_base); + } setpts->var_values[VAR_PTS ] = TS2D(pts); setpts->var_values[VAR_T ] = TS2T(pts, inlink->time_base); #if FF_API_FRAME_PKT @@ -269,14 +275,45 @@ static av_cold void uninit(AVFilterContext *ctx) setpts->expr = NULL; } +static int process_command(AVFilterContext *ctx, const char *cmd, const char *arg, + char *res, int res_len, int flags) +{ + SetPTSContext *setpts = ctx->priv; + AVExpr *new_expr; + int ret; + + ret = ff_filter_process_command(ctx, cmd, arg, res, res_len, flags); + + if (ret < 0) + return ret; + + if (!strcmp(cmd, "expr")) { + ret = av_expr_parse(&new_expr, arg, var_names, NULL, NULL, NULL, NULL, 0, ctx); + // Only free and replace previous expression if new one succeeds, + // otherwise defensively keep everything intact even if reporting an error. + if (ret < 0) { + av_log(ctx, AV_LOG_ERROR, "Error while parsing expression '%s'\n", arg); + } else { + av_expr_free(setpts->expr); + setpts->expr = new_expr; + setpts->var_values[VAR_T_CHANGE] = NAN; + } + } else { + ret = AVERROR(EINVAL); + } + + return ret; +} + #define OFFSET(x) offsetof(SetPTSContext, x) #define V AV_OPT_FLAG_VIDEO_PARAM #define A AV_OPT_FLAG_AUDIO_PARAM +#define R AV_OPT_FLAG_RUNTIME_PARAM #define F AV_OPT_FLAG_FILTERING_PARAM #if CONFIG_SETPTS_FILTER static const AVOption setpts_options[] = { - { "expr", "Expression determining the frame timestamp", OFFSET(expr_str), AV_OPT_TYPE_STRING, { .str = "PTS" }, .flags = V|F }, + { "expr", "Expression determining the frame timestamp", OFFSET(expr_str), AV_OPT_TYPE_STRING, { .str = "PTS" }, .flags = V|F|R }, { NULL } }; AVFILTER_DEFINE_CLASS(setpts); @@ -297,12 +334,13 @@ static const AVFilterPad avfilter_vf_setpts_outputs[] = { }; const AVFilter ff_vf_setpts = { - .name = "setpts", - .description = NULL_IF_CONFIG_SMALL("Set PTS for the output video frame."), - .init = init, - .activate = activate, - .uninit = uninit, - .flags = AVFILTER_FLAG_METADATA_ONLY, + .name = "setpts", + .description = NULL_IF_CONFIG_SMALL("Set PTS for the output video frame."), + .init = init, + .activate = activate, + .uninit = uninit, + .process_command = process_command, + .flags = AVFILTER_FLAG_METADATA_ONLY, .priv_size = sizeof(SetPTSContext), .priv_class = &setpts_class, @@ -315,7 +353,7 @@ const AVFilter ff_vf_setpts = { #if CONFIG_ASETPTS_FILTER static const AVOption asetpts_options[] = { - { "expr", "Expression determining the frame timestamp", OFFSET(expr_str), AV_OPT_TYPE_STRING, { .str = "PTS" }, .flags = A|F }, + { "expr", "Expression determining the frame timestamp", OFFSET(expr_str), AV_OPT_TYPE_STRING, { .str = "PTS" }, .flags = A|F|R }, { NULL } }; AVFILTER_DEFINE_CLASS(asetpts); @@ -336,14 +374,15 @@ static const AVFilterPad asetpts_outputs[] = { }; const AVFilter ff_af_asetpts = { - .name = "asetpts", - .description = NULL_IF_CONFIG_SMALL("Set PTS for the output audio frame."), - .init = init, - .activate = activate, - .uninit = uninit, - .priv_size = sizeof(SetPTSContext), - .priv_class = &asetpts_class, - .flags = AVFILTER_FLAG_METADATA_ONLY, + .name = "asetpts", + .description = NULL_IF_CONFIG_SMALL("Set PTS for the output audio frame."), + .init = init, + .activate = activate, + .uninit = uninit, + .process_command = process_command, + .priv_size = sizeof(SetPTSContext), + .priv_class = &asetpts_class, + .flags = AVFILTER_FLAG_METADATA_ONLY, FILTER_INPUTS(asetpts_inputs), FILTER_OUTPUTS(asetpts_outputs), }; -- cgit v1.2.3