vf_select: switch to filter_frame

The new code reads the input frame when its ready, the previous
code did read the input frame during start_frame at which point it
may not yet be available.
Signed-off-by: Michael Niedermayer <michaelni@gmx.at>

libavfilter/vf_select.c

@@ -289,50 +289,27 @@ static int select_frame(AVFilterContext *ctx, AVFilterBufferRef *picref)
     return res;
 }
 
-static int start_frame(AVFilterLink *inlink, AVFilterBufferRef *picref)
+static int filter_frame(AVFilterLink *inlink, AVFilterBufferRef *frame)
 {
     SelectContext *select = inlink->dst->priv;
 
-    select->select = select_frame(inlink->dst, picref);
+    select->select = select_frame(inlink->dst, frame);
     if (select->select) {
-        AVFilterBufferRef *buf_out;
         /* frame was requested through poll_frame */
         if (select->cache_frames) {
-            if (!av_fifo_space(select->pending_frames))
+            if (!av_fifo_space(select->pending_frames)) {
                 av_log(inlink->dst, AV_LOG_ERROR,
                        "Buffering limit reached, cannot cache more frames\n");
-            else
-                av_fifo_generic_write(select->pending_frames, &picref,
-                                      sizeof(picref), NULL);
+                avfilter_unref_bufferp(&frame);
+            } else
+                av_fifo_generic_write(select->pending_frames, &frame,
+                                      sizeof(frame), NULL);
             return 0;
         }
-        buf_out = avfilter_ref_buffer(picref, ~0);
-        if (!buf_out)
-            return AVERROR(ENOMEM);
-        return ff_start_frame(inlink->dst->outputs[0], buf_out);
+        return ff_filter_frame(inlink->dst->outputs[0], frame);
     }
 
-    return 0;
-}
-
-static int draw_slice(AVFilterLink *inlink, int y, int h, int slice_dir)
-{
-    SelectContext *select = inlink->dst->priv;
-
-    if (select->select && !select->cache_frames)
-        return ff_draw_slice(inlink->dst->outputs[0], y, h, slice_dir);
-    return 0;
-}
-
-static int end_frame(AVFilterLink *inlink)
-{
-    SelectContext *select = inlink->dst->priv;
-
-    if (select->select) {
-        if (select->cache_frames)
-            return 0;
-        return ff_end_frame(inlink->dst->outputs[0]);
-    }
+    avfilter_unref_bufferp(&frame);
     return 0;
 }
 
@@ -345,14 +322,9 @@ static int request_frame(AVFilterLink *outlink)
 
     if (av_fifo_size(select->pending_frames)) {
         AVFilterBufferRef *picref;
-        int ret;
 
         av_fifo_generic_read(select->pending_frames, &picref, sizeof(picref), NULL);
-        if ((ret = ff_start_frame(outlink, picref)) < 0 ||
-            (ret = ff_draw_slice(outlink, 0, outlink->h, 1)) < 0 ||
-            (ret = ff_end_frame(outlink)) < 0);
-
-        return ret;
+        return ff_filter_frame(outlink, picref);
     }
 
     while (!select->select) {
@@ -432,9 +404,7 @@ static const AVFilterPad avfilter_vf_select_inputs[] = {
         .get_video_buffer = ff_null_get_video_buffer,
         .min_perms        = AV_PERM_PRESERVE,
         .config_props     = config_input,
-        .start_frame      = start_frame,
-        .draw_slice       = draw_slice,
-        .end_frame        = end_frame
+        .filter_frame     = filter_frame,
     },
     { NULL }
 };

tests/ref/fate/filter-metadata-scenedetect

-video|1|20|0.033333|20|0.033333|1|0.001667|29927|320|240|rgb24|1:1|I|0|0|0|0|0|0|1.000000
-video|1|1640|2.733333|1640|2.733333|1|0.001667|164269|320|240|rgb24|1:1|I|0|0|0|0|0|0|1.000000
-video|1|4160|6.933333|4160|6.933333|1|0.001667|808833|320|240|rgb24|1:1|I|0|0|0|0|0|0|0.880000
-video|1|5820|9.700000|5820|9.700000|1|0.001667|933313|320|240|rgb24|1:1|I|0|0|0|0|0|0|1.000000
-video|1|6740|11.233333|6740|11.233333|1|0.001667|1040437|320|240|rgb24|1:1|I|0|0|0|0|0|0|0.460000
-video|1|8180|13.633333|8180|13.633333|1|0.001667|1248589|320|240|rgb24|1:1|I|0|0|0|0|0|0|1.000000
-video|1|9780|16.300000|9780|16.300000|1|0.001667|1348821|320|240|rgb24|1:1|I|0|0|0|0|0|0|1.000000
-video|1|14100|23.500000|14100|23.500000|1|0.001667|2006431|320|240|rgb24|1:1|I|0|0|0|0|0|0|0.840000
-video|1|15720|26.200000|15720|26.200000|1|0.001667|2151283|320|240|rgb24|1:1|I|0|0|0|0|0|0|1.000000
-video|1|18520|30.866667|18520|30.866667|1|0.001667|2515017|320|240|rgb24|1:1|I|0|0|0|0|0|0|0.470000
-video|1|21780|36.300000|21780|36.300000|1|0.001667|2933379|320|240|rgb24|1:1|I|0|0|0|0|0|0|1.000000
+video|1|1620|2.700000|1620|2.700000|1|0.001667|155751|320|240|rgb24|1:1|I|0|0|0|0|0|0|1.000000
+video|1|4140|6.900000|4140|6.900000|1|0.001667|808205|320|240|rgb24|1:1|I|0|0|0|0|0|0|0.880000
+video|1|5800|9.666667|5800|9.666667|1|0.001667|928577|320|240|rgb24|1:1|I|0|0|0|0|0|0|1.000000
+video|1|6720|11.200000|6720|11.200000|1|0.001667|1027359|320|240|rgb24|1:1|I|0|0|0|0|0|0|0.460000
+video|1|8160|13.600000|8160|13.600000|1|0.001667|1247869|320|240|rgb24|1:1|I|0|0|0|0|0|0|1.000000
+video|1|9760|16.266667|9760|16.266667|1|0.001667|1337561|320|240|rgb24|1:1|I|0|0|0|0|0|0|1.000000
+video|1|14080|23.466667|14080|23.466667|1|0.001667|1994159|320|240|rgb24|1:1|I|0|0|0|0|0|0|0.840000
+video|1|15700|26.166667|15700|26.166667|1|0.001667|2145781|320|240|rgb24|1:1|I|0|0|0|0|0|0|1.000000
+video|1|18500|30.833333|18500|30.833333|1|0.001667|2507729|320|240|rgb24|1:1|I|0|0|0|0|0|0|0.470000
+video|1|21760|36.266667|21760|36.266667|1|0.001667|2932267|320|240|rgb24|1:1|I|0|0|0|0|0|0|1.000000