X-Git-Url: https://git.libav.org/?p=libav.git;a=blobdiff_plain;f=libavfilter%2Fvf_slicify.c;h=d1c9fbc6ac353b55edc204141b20252d188f1be3;hp=40824cefdc668103d6842f91ed74677714cecc5a;hb=94a5218c108d078491aa69db72433f2918bdab5d;hpb=bc37ec923debca2647b086306d360341b2492bfe

diff --git a/libavfilter/vf_slicify.c b/libavfilter/vf_slicify.c
index 40824cefdc..d1c9fbc6ac 100644
--- a/libavfilter/vf_slicify.c
+++ b/libavfilter/vf_slicify.c
@@ -24,6 +24,7 @@
  */
 
 #include "avfilter.h"
+#include "libavutil/pixdesc.h"
 
 typedef struct {
     int h;          ///< output slice height
@@ -44,9 +45,8 @@ static av_cold int init(AVFilterContext *ctx, const char *args, void *opaque)
 static int config_props(AVFilterLink *link)
 {
     SliceContext *slice = link->dst->priv;
-    int tmp;
 
-    avcodec_get_chroma_sub_sample(link->format, &tmp, &slice->vshift);
+    slice->vshift = av_pix_fmt_descriptors[link->format].log2_chroma_h;
 
     /* ensure that slices play nice with chroma subsampling, and enforce
      * a reasonable minimum size for the slices */
@@ -73,16 +73,24 @@ static void end_frame(AVFilterLink *link)
     avfilter_end_frame(link->dst->outputs[0]);
 }
 
-static void draw_slice(AVFilterLink *link, int y, int h)
+static void draw_slice(AVFilterLink *link, int y, int h, int slice_dir)
 {
     SliceContext *slice = link->dst->priv;
     int y2;
 
-    for (y2 = y; y2 + slice->h <= y + h; y2 += slice->h)
-        avfilter_draw_slice(link->dst->outputs[0], y2, slice->h);
+    if (slice_dir == 1) {
+        for (y2 = y; y2 + slice->h <= y + h; y2 += slice->h)
+            avfilter_draw_slice(link->dst->outputs[0], y2, slice->h, slice_dir);
 
-    if (y2 < y + h)
-        avfilter_draw_slice(link->dst->outputs[0], y2, y + h - y2);
+        if (y2 < y + h)
+            avfilter_draw_slice(link->dst->outputs[0], y2, y + h - y2, slice_dir);
+    } else if (slice_dir == -1) {
+        for (y2 = y + h; y2 - slice->h >= y; y2 -= slice->h)
+            avfilter_draw_slice(link->dst->outputs[0], y2 - slice->h, slice->h, slice_dir);
+
+        if (y2 > y)
+            avfilter_draw_slice(link->dst->outputs[0], y, y2 - y, slice_dir);
+    }
 }
 
 AVFilter avfilter_vf_slicify = {