lavfi/blackframe: add support for named options

1 files changed, 28 insertions, 12 deletions

diff --git a/libavfilter/vf_blackframe.c b/libavfilter/vf_blackframe.c
index 52c56d8bc2..a69ed97a52 100644
--- a/libavfilter/vf_blackframe.c
+++ b/libavfilter/vf_blackframe.c
@@ -31,6 +31,7 @@
 #include <inttypes.h>
 
 #include "libavutil/internal.h"
+#include "libavutil/opt.h"
 #include "avfilter.h"
 #include "internal.h"
 #include "formats.h"
@@ -38,6 +39,7 @@
 #include "video.h"
 
 typedef struct {
+    const AVClass *class;
     unsigned int bamount; ///< black amount
     unsigned int bthresh; ///< black threshold
     unsigned int frame;   ///< frame number
@@ -45,6 +47,17 @@ typedef struct {
     unsigned int last_keyframe; ///< frame number of the last received key-frame
 } BlackFrameContext;
 
+#define OFFSET(x) offsetof(BlackFrameContext, x)
+#define FLAGS AV_OPT_FLAG_VIDEO_PARAM|AV_OPT_FLAG_FILTERING_PARAM
+
+static const AVOption blackframe_options[] = {
+    { "amount", "set least percentual amount of pixels below the black threshold enabling black detection", OFFSET(bamount), AV_OPT_TYPE_INT, {.i64=98}, 0, 100, FLAGS },
+    { "thresh", "set threshold below which a pixel value is considered black", OFFSET(bthresh), AV_OPT_TYPE_INT, {.i64=32}, 0, 255, FLAGS },
+    { NULL }
+};
+
+AVFILTER_DEFINE_CLASS(blackframe);
+
 static int query_formats(AVFilterContext *ctx)
 {
     static const enum AVPixelFormat pix_fmts[] = {
@@ -60,27 +73,27 @@ static int query_formats(AVFilterContext *ctx)
 static av_cold int init(AVFilterContext *ctx, const char *args)
 {
     BlackFrameContext *blackframe = ctx->priv;
+    static const char *shorthand[] = { "amount", "thresh", NULL };
+    int ret;
 
-    blackframe->bamount = 98;
-    blackframe->bthresh = 32;
-    blackframe->nblack = 0;
-    blackframe->frame = 0;
-    blackframe->last_keyframe = 0;
+    blackframe->class = &blackframe_class;
+    av_opt_set_defaults(blackframe);
 
-    if (args)
-        sscanf(args, "%u:%u", &blackframe->bamount, &blackframe->bthresh);
+    if ((ret = av_opt_set_from_string(blackframe, args, shorthand, "=", ":")) < 0)
+        return ret;
 
     av_log(ctx, AV_LOG_VERBOSE, "bamount:%u bthresh:%u\n",
            blackframe->bamount, blackframe->bthresh);
 
-    if (blackframe->bamount > 100 || blackframe->bthresh > 255) {
-        av_log(ctx, AV_LOG_ERROR, "Too big value for bamount (max is 100) or bthresh (max is 255)\n");
-        return AVERROR(EINVAL);
-    }
-
     return 0;
 }
 
+static av_cold void uninit(AVFilterContext *ctx)
+{
+    BlackFrameContext *blackframe = ctx->priv;
+    av_opt_free(blackframe);
+}
+
 static int filter_frame(AVFilterLink *inlink, AVFrame *frame)
 {
     AVFilterContext *ctx = inlink->dst;
@@ -135,10 +148,13 @@ AVFilter avfilter_vf_blackframe = {
 
     .priv_size = sizeof(BlackFrameContext),
     .init      = init,
+    .uninit    = uninit,
 
     .query_formats = query_formats,
 
     .inputs    = avfilter_vf_blackframe_inputs,
 
     .outputs   = avfilter_vf_blackframe_outputs,
+
+    .priv_class = &blackframe_class,
 };