Merge remote-tracking branch 'richardpl/framestep'

* richardpl/framestep:
  lavfi/framestep: remove request_frame hack
  lavfi/framestep: switch to an AVOptions-based system
Merged-by: Michael Niedermayer <michaelni@gmx.at>

doc/filters.texi

@@ -3212,10 +3212,14 @@ See also the @ref{setpts} filter.
 
 @section framestep
 
-Select one frame every N.
+Select one frame every N-th frame.
 
-This filter accepts in input a string representing a positive
-integer. Default argument is @code{1}.
+This filter accepts the following option:
+@table @option
+@item step
+Select frame after every @code{step} frames.
+Allowed values are positive integers higher than 0. Default value is @code{1}.
+@end table
 
 @anchor{frei0r}
 @section frei0r

libavfilter/avfilter.c

@@ -683,6 +683,7 @@ int avfilter_init_filter(AVFilterContext *filter, const char *args, void *opaque
         !strcmp(filter->filter->name,  "field"     ) ||
         !strcmp(filter->filter->name,  "fieldorder") ||
         !strcmp(filter->filter->name,  "fps"       ) ||
+        !strcmp(filter->filter->name,  "framestep" ) ||
         !strcmp(filter->filter->name,  "frei0r"    ) ||
         !strcmp(filter->filter->name,  "frei0r_src") ||
         !strcmp(filter->filter->name,  "geq"       ) ||

libavfilter/vf_framestep.c

@@ -23,32 +23,25 @@
  * Daniele Fornighieri <guru AT digitalfantasy it>.
  */
 
+#include "libavutil/opt.h"
 #include "avfilter.h"
 #include "internal.h"
 #include "video.h"
 
 typedef struct {
-    int frame_step, frame_count, frame_selected;
+    const AVClass *class;
+    int frame_step, frame_count;
 } FrameStepContext;
 
-static av_cold int init(AVFilterContext *ctx, const char *args)
-{
-    FrameStepContext *framestep = ctx->priv;
-    char *tailptr;
-    long int n = 1;
+#define OFFSET(x) offsetof(FrameStepContext, x)
+#define FLAGS AV_OPT_FLAG_FILTERING_PARAM|AV_OPT_FLAG_VIDEO_PARAM
 
-    if (args) {
-        n = strtol(args, &tailptr, 10);
-        if (*tailptr || n <= 0 || n >= INT_MAX) {
-            av_log(ctx, AV_LOG_ERROR,
-                   "Invalid argument '%s', must be a positive integer <= INT_MAX\n", args);
-            return AVERROR(EINVAL);
-        }
-    }
+static const AVOption framestep_options[] = {
+    { "step", "set frame step",  OFFSET(frame_step), AV_OPT_TYPE_INT, {.i64=1}, 1, INT_MAX, FLAGS},
+    {NULL},
+};
 
-    framestep->frame_step = n;
-    return 0;
-}
+AVFILTER_DEFINE_CLASS(framestep);
 
 static int config_output_props(AVFilterLink *outlink)
 {
@@ -56,6 +49,7 @@ static int config_output_props(AVFilterLink *outlink)
     FrameStepContext *framestep = ctx->priv;
     AVFilterLink *inlink = ctx->inputs[0];
 
+    outlink->flags |= FF_LINK_FLAG_REQUEST_LOOP;
     outlink->frame_rate =
         av_div_q(inlink->frame_rate, (AVRational){framestep->frame_step, 1});
 
@@ -71,34 +65,17 @@ static int filter_frame(AVFilterLink *inlink, AVFrame *ref)
     FrameStepContext *framestep = inlink->dst->priv;
 
     if (!(framestep->frame_count++ % framestep->frame_step)) {
-        framestep->frame_selected = 1;
         return ff_filter_frame(inlink->dst->outputs[0], ref);
     } else {
-        framestep->frame_selected = 0;
         av_frame_free(&ref);
         return 0;
     }
 }
 
-static int request_frame(AVFilterLink *outlink)
-{
-    FrameStepContext *framestep = outlink->src->priv;
-    AVFilterLink *inlink = outlink->src->inputs[0];
-    int ret;
-
-    framestep->frame_selected = 0;
-    do {
-        ret = ff_request_frame(inlink);
-    } while (!framestep->frame_selected && ret >= 0);
-
-    return ret;
-}
-
 static const AVFilterPad framestep_inputs[] = {
     {
         .name             = "default",
         .type             = AVMEDIA_TYPE_VIDEO,
-        .get_video_buffer = ff_null_get_video_buffer,
         .filter_frame     = filter_frame,
     },
     { NULL }
@@ -109,7 +86,6 @@ static const AVFilterPad framestep_outputs[] = {
         .name          = "default",
         .type          = AVMEDIA_TYPE_VIDEO,
         .config_props  = config_output_props,
-        .request_frame = request_frame,
     },
     { NULL }
 };
@@ -117,8 +93,8 @@ static const AVFilterPad framestep_outputs[] = {
 AVFilter avfilter_vf_framestep = {
     .name      = "framestep",
     .description = NULL_IF_CONFIG_SMALL("Select one frame every N frames."),
-    .init      = init,
     .priv_size = sizeof(FrameStepContext),
+    .priv_class = &framestep_class,
     .inputs    = framestep_inputs,
     .outputs   = framestep_outputs,
 };