lavc/vp56: Refactor ff_vp56_init into ff_vp56_init/ff_vp56_init_context

Pave the way for per-thread context initialization.
Signed-off-by: Ben Jackson <ben@ben.com>
Signed-off-by: Michael Niedermayer <michaelni@gmx.at>

libavcodec/vp56.c

@@ -661,6 +661,12 @@ int ff_vp56_decode_frame(AVCodecContext *avctx, void *data, int *data_size,
 av_cold void ff_vp56_init(AVCodecContext *avctx, int flip, int has_alpha)
 {
     VP56Context *s = avctx->priv_data;
+    ff_vp56_init_context(avctx, s, flip, has_alpha);
+}
+
+av_cold void ff_vp56_init_context(AVCodecContext *avctx, VP56Context *s,
+                                  int flip, int has_alpha)
+{
     int i;
 
     s->avctx = avctx;
@@ -702,6 +708,12 @@ av_cold void ff_vp56_init(AVCodecContext *avctx, int flip, int has_alpha)
 av_cold int ff_vp56_free(AVCodecContext *avctx)
 {
     VP56Context *s = avctx->priv_data;
+    return ff_vp56_free_context(s);
+}
+
+av_cold int ff_vp56_free_context(VP56Context *s)
+{
+    AVCodecContext *avctx = s->avctx;
 
     av_freep(&s->qscale_table);
     av_freep(&s->above_blocks);

libavcodec/vp56.h

@@ -174,7 +174,10 @@ struct vp56_context {
 
 
 void ff_vp56_init(AVCodecContext *avctx, int flip, int has_alpha);
+void ff_vp56_init_context(AVCodecContext *avctx, VP56Context *s,
+                          int flip, int has_alpha);
 int ff_vp56_free(AVCodecContext *avctx);
+int ff_vp56_free_context(VP56Context *s);
 void ff_vp56_init_dequant(VP56Context *s, int quantizer);
 int ff_vp56_decode_frame(AVCodecContext *avctx, void *data, int *data_size,
                          AVPacket *avpkt);