sub: basic subtitle converters

Add a basic infrastructure for subtitle converters. These converters
work sort-of like decoders, except that they produce packets instead
of subtitle bitmaps. They are put in front of actual decoders.

Start with sd_movtext. 4 lines of code are blown up to a 55 lines file,
but fortunately this is not going to be that bad for the following
converters.

1 files changed, 1 insertions, 0 deletions

diff --git a/Makefile b/Makefile
index 6e52253543..583eaf87ec 100644
--- a/Makefile
+++ b/Makefile
@@ -231,6 +231,7 @@ SOURCES = talloc.c \
           sub/find_subfiles.c \
           sub/img_convert.c \
           sub/sd_lavc.c \
+          sub/sd_movtext.c \
           sub/sd_spu.c \
           sub/spudec.c \
           sub/sub.c \