sub: allow converting DVD subs to RGBA

The mplayer DVD sub decoder is the only remaining OSD image producer
that still requires the old mplayer OSD format (SUBBITMAP_OLD_PLANAR).

To make supporting this format optional in VOs, add a step that allows
converting these images to RGBA in case the VO doesn't have direct
support for it.

Note: the mplayer DVD sub decoder uses the old mplayer OSD format
(SUBBITMAP_OLD_PLANAR), which is assumed to use premultiplied alpha.
However, it seems DVDs allow only binary transparency, so the rendered
result will be the same.

1 files changed, 1 insertions, 1 deletions

diff --git a/sub/sub.h b/sub/sub.h
index 1dee0c8a8f..7deaf73b8e 100644
--- a/sub/sub.h
+++ b/sub/sub.h
@@ -34,7 +34,7 @@ struct vo;
 
 #define MAX_OSD_PARTS 5
 
-#define OSD_CONV_CACHE_MAX 2
+#define OSD_CONV_CACHE_MAX 3
 
 struct osd_object {
     int type; // OSDTYPE_*