lavc: add ff_init_buffer_info()

Fixes seeking per fileposition in ffplay.
Signed-off-by: Michael Niedermayer <michaelni@gmx.at>

libavcodec/internal.h

@@ -55,4 +55,9 @@ int ff_match_2uint16(const uint16_t (*tab)[2], int size, int a, int b);
 
 unsigned int ff_toupper4(unsigned int x);
 
+/**
+ * does needed setup of pkt_pts/pos and such for (re)get_buffer();
+ */
+void ff_init_buffer_info(AVCodecContext *s, AVFrame *pic);
+
 #endif /* AVCODEC_INTERNAL_H */

libavcodec/pthread.c

@@ -32,6 +32,7 @@
 #include <pthread.h>
 
 #include "avcodec.h"
+#include "internal.h"
 #include "thread.h"
 
 typedef int (action_func)(AVCodecContext *c, void *arg);
@@ -787,6 +788,8 @@ int ff_thread_get_buffer(AVCodecContext *avctx, AVFrame *f)
 
     f->owner = avctx;
 
+    ff_init_buffer_info(avctx, f);
+
     if (!(avctx->active_thread_type&FF_THREAD_FRAME)) {
         f->thread_opaque = NULL;
         return avctx->get_buffer(avctx, f);

libavcodec/utils.c

@@ -238,6 +238,22 @@ void avcodec_align_dimensions(AVCodecContext *s, int *width, int *height){
     *width=FFALIGN(*width, align);
 }
 
+void ff_init_buffer_info(AVCodecContext *s, AVFrame *pic)
+{
+    if (s->pkt) {
+        pic->pkt_pts = s->pkt->pts;
+        pic->pkt_pos = s->pkt->pos;
+    } else {
+        pic->pkt_pts = AV_NOPTS_VALUE;
+        pic->pkt_pos = -1;
+    }
+    pic->reordered_opaque= s->reordered_opaque;
+    pic->sample_aspect_ratio = s->sample_aspect_ratio;
+    pic->width               = s->width;
+    pic->height              = s->height;
+    pic->format              = s->pix_fmt;
+}
+
 int avcodec_default_get_buffer(AVCodecContext *s, AVFrame *pic){
     int i;
     int w= s->width;
@@ -1357,6 +1373,9 @@ unsigned int ff_toupper4(unsigned int x)
 int ff_thread_get_buffer(AVCodecContext *avctx, AVFrame *f)
 {
     f->owner = avctx;
+
+    ff_init_buffer_info(avctx, f);
+
     return avctx->get_buffer(avctx, f);
 }