[vlc-devel] [PATCH v1 14/33] filter_chain: use a local video sink to implement filter_chain_VideoFilter

[Steve Lhomme]

We assert that only one picture can be received by this picture chain.
Otherwise the caller should have used filter_chain_VideoFilterInto.

The difference of filter usage/expectations could be enforced by using two
different types.
---
 src/misc/filter_chain.c | 34 ++++++++++++++++------------------
 1 file changed, 16 insertions(+), 18 deletions(-)

diff --git a/src/misc/filter_chain.c b/src/misc/filter_chain.c
index 3019d67e749..083ed165f62 100644
--- a/src/misc/filter_chain.c
+++ b/src/misc/filter_chain.c
@@ -449,26 +449,24 @@ static picture_t *FilterChainVideoFilter( chained_filter_t *f, picture_t *p_pic
     return p_pic;
 }
 
+static int FilterChainLastPush(struct vlc_video_sink *sink, picture_t *p_pic)
+{
+    picture_t **outpic = sink->sys;
+    assert(*outpic == NULL);
+    *outpic = p_pic;
+    return VLC_SUCCESS;
+}
+
 picture_t *filter_chain_VideoFilter( filter_chain_t *p_chain, picture_t *p_pic )
 {
-    if( p_pic )
-    {
-        p_pic = FilterChainVideoFilter( p_chain->first, p_pic );
-        if( p_pic )
-            return p_pic;
-    }
-    for( chained_filter_t *b = p_chain->last; b != NULL; b = b->prev )
-    {
-        if( vlc_picture_chain_IsEmpty( &b->pending ) )
-            continue;
-        p_pic = b->pending.front;
-        b->pending = picture_GetAndResetChain( p_pic );
-
-        p_pic = FilterChainVideoFilter( b->next, p_pic );
-        if( p_pic )
-            return p_pic;
-    }
-    return NULL;
+    picture_t *result = NULL;
+    struct vlc_video_sink output = { &result, FilterChainLastPush };
+    int res;
+    assert( p_pic );
+    res = filter_chain_VideoFilterInto( p_chain, p_pic, &output );
+    // use filter_chain_VideoFilterInto to get all output at once
+    assert(!picture_HasChainedPics(result));
+    return result;
 }
 
 int filter_chain_VideoFilterInto(filter_chain_t *p_chain, picture_t *p_pic,
-- 
2.26.2