avcodec/codec_internal: Add FFCodec.decode_sub

This increases type-safety by avoiding conversions from/through void*.
It also avoids the boilerplate "AVSubtitle *sub = data;" line
for subtitle decoders. Its only downside is that it increases
sizeof(FFCodec), yet this can be more than offset lateron.

Signed-off-by: Andreas Rheinhardt <andreas.rheinhardt@outlook.com>

1 files changed, 4 insertions, 4 deletions

diff --git a/libavcodec/xsubdec.c b/libavcodec/xsubdec.c
index cb7b7b7cab..c2c1b920cc 100644
--- a/libavcodec/xsubdec.c
+++ b/libavcodec/xsubdec.c
@@ -47,11 +47,11 @@ static int64_t parse_timecode(const uint8_t *buf, int64_t packet_time) {
     return ms - packet_time;
 }
 
-static int decode_frame(AVCodecContext *avctx, void *data, int *got_sub_ptr,
-                        AVPacket *avpkt) {
+static int decode_frame(AVCodecContext *avctx, AVSubtitle *sub,
+                        int *got_sub_ptr, AVPacket *avpkt)
+{
     const uint8_t *buf = avpkt->data;
     int buf_size = avpkt->size;
-    AVSubtitle *sub = data;
     AVSubtitleRect *rect;
     const uint8_t *buf_end = buf + buf_size;
     uint8_t *bitmap;
@@ -160,6 +160,6 @@ const FFCodec ff_xsub_decoder = {
     .p.type    = AVMEDIA_TYPE_SUBTITLE,
     .p.id      = AV_CODEC_ID_XSUB,
     .init      = decode_init,
-    .decode    = decode_frame,
+    .decode_sub = decode_frame,
     .caps_internal = FF_CODEC_CAP_INIT_THREADSAFE,
 };