Fix regression test failure with pthreads on multiprocessor systems.

Fixes issue517

Originally committed as revision 15976 to svn://svn.ffmpeg.org/ffmpeg/trunk

libavcodec/motion_est.c

@@ -307,8 +307,6 @@ int ff_init_me(MpegEncContext *s){
         c->sub_motion_search= no_sub_motion_search;
     }
 
-    c->temp= c->scratchpad;
-
     return 0;
 }
 

libavcodec/mpegvideo.c

@@ -289,6 +289,7 @@ static int init_duplicate_context(MpegEncContext *s, MpegEncContext *base){
 
      //FIXME should be linesize instead of s->width*2 but that is not known before get_buffer()
     CHECKED_ALLOCZ(s->me.scratchpad,  (s->width+64)*4*16*2*sizeof(uint8_t))
+    s->me.temp=         s->me.scratchpad;
     s->rd_scratchpad=   s->me.scratchpad;
     s->b_scratchpad=    s->me.scratchpad;
     s->obmc_scratchpad= s->me.scratchpad + 16;
@@ -315,6 +316,7 @@ static void free_duplicate_context(MpegEncContext *s){
 
     av_freep(&s->allocated_edge_emu_buffer); s->edge_emu_buffer= NULL;
     av_freep(&s->me.scratchpad);
+    s->me.temp=
     s->rd_scratchpad=
     s->b_scratchpad=
     s->obmc_scratchpad= NULL;
@@ -331,6 +333,7 @@ static void backup_duplicate_context(MpegEncContext *bak, MpegEncContext *src){
     COPY(allocated_edge_emu_buffer);
     COPY(edge_emu_buffer);
     COPY(me.scratchpad);
+    COPY(me.temp);
     COPY(rd_scratchpad);
     COPY(b_scratchpad);
     COPY(obmc_scratchpad);

libavcodec/snow.c

@@ -4007,6 +4007,7 @@ static av_cold int encode_init(AVCodecContext *avctx)
     s->m.flags   = avctx->flags;
     s->m.bit_rate= avctx->bit_rate;
 
+    s->m.me.temp      =
     s->m.me.scratchpad= av_mallocz((avctx->width+64)*2*16*2*sizeof(uint8_t));
     s->m.me.map       = av_mallocz(ME_MAP_SIZE*sizeof(uint32_t));
     s->m.me.score_map = av_mallocz(ME_MAP_SIZE*sizeof(uint32_t));
@@ -4435,6 +4436,7 @@ static av_cold void common_end(SnowContext *s){
     av_freep(&s->spatial_dwt_buffer);
     av_freep(&s->spatial_idwt_buffer);
 
+    s->m.me.temp= NULL;
     av_freep(&s->m.me.scratchpad);
     av_freep(&s->m.me.map);
     av_freep(&s->m.me.score_map);