multithreaded mpeg2 decoding

Originally committed as revision 2810 to svn://svn.ffmpeg.org/ffmpeg/trunk

ffmpeg.c

@@ -2256,6 +2256,11 @@ static void opt_input_file(const char *filename)
     /* update the current parameters so that they match the one of the input stream */
     for(i=0;i<ic->nb_streams;i++) {
         AVCodecContext *enc = &ic->streams[i]->codec;
+#if defined(HAVE_PTHREADS) || defined(HAVE_W32THREADS)
+        if(thread_count>1)
+            avcodec_thread_init(enc, thread_count);
+#endif
+        enc->thread_count= thread_count;
         switch(enc->codec_type) {
         case CODEC_TYPE_AUDIO:
             //fprintf(stderr, "\nInput Audio channels: %d", enc->channels);

ffplay.c

@@ -168,6 +168,7 @@ static int64_t start_time = AV_NOPTS_VALUE;
 static int debug = 0;
 static int debug_mv = 0;
 static int step = 0;
+static int thread_count = 1;
 
 /* current context */
 static int is_full_screen;
@@ -1169,6 +1170,12 @@ static int stream_component_open(VideoState *is, int stream_index)
     if (!codec ||
         avcodec_open(enc, codec) < 0)
         return -1;
+    enc->debug = debug;
+#if defined(HAVE_PTHREADS) || defined(HAVE_W32THREADS)
+    if(thread_count>1)
+        avcodec_thread_init(enc, thread_count);
+#endif
+    enc->thread_count= thread_count;
     switch(enc->codec_type) {
     case CODEC_TYPE_AUDIO:
         is->audio_stream = stream_index;
@@ -1197,7 +1204,6 @@ static int stream_component_open(VideoState *is, int stream_index)
 
         packet_queue_init(&is->videoq);
         is->video_tid = SDL_CreateThread(video_thread, is);
-        enc->debug = debug;
         enc->debug_mv = debug_mv;
         break;
     default:
@@ -1794,6 +1800,14 @@ static void opt_vismv(const char *arg)
     debug_mv = atoi(arg);
 }
 
+static void opt_thread_count(const char *arg)
+{
+    thread_count= atoi(arg);
+#if !defined(HAVE_PTHREADS) && !defined(HAVE_W32THREADS)
+    fprintf(stderr, "Warning: not compiled with thread support, using thread emulation\n");
+#endif
+}
+    
 const OptionDef options[] = {
     { "h", 0, {(void*)show_help}, "show help" },    
     { "x", HAS_ARG, {(void*)opt_width}, "force displayed width", "width" },
@@ -1814,7 +1828,8 @@ const OptionDef options[] = {
 #ifdef CONFIG_NETWORK
     { "rtp_tcp", OPT_EXPERT, {(void*)&opt_rtp_tcp}, "force RTP/TCP protocol usage", "" },
 #endif
-    { "sync", HAS_ARG | OPT_EXPERT, {(void*)&opt_sync}, "set audio-video sync. type (type=audio/video/ext)", "type" },
+    { "sync", HAS_ARG | OPT_EXPERT, {(void*)opt_sync}, "set audio-video sync. type (type=audio/video/ext)", "type" },
+    { "threads", HAS_ARG | OPT_EXPERT, {(void*)opt_thread_count}, "thread count", "count" },
     { NULL, },
 };
 

libavcodec/error_resilience.c

@@ -652,7 +652,7 @@ void ff_er_add_slice(MpegEncContext *s, int startx, int starty, int endx, int en
  
     s->error_status_table[start_xy] |= VP_START;
 
-    if(start_xy > 0){
+    if(start_xy > 0 && s->avctx->thread_count <= 1){
         int prev_status= s->error_status_table[ s->mb_index2xy[start_i - 1] ];
         
         prev_status &= ~ VP_START;

libavcodec/mpegvideo.c

@@ -468,13 +468,17 @@ static void backup_duplicate_context(MpegEncContext *bak, MpegEncContext *src){
 #undef COPY
 }
 
-static void update_duplicate_context(MpegEncContext *dst, MpegEncContext *src){
+void ff_update_duplicate_context(MpegEncContext *dst, MpegEncContext *src){
     MpegEncContext bak;
+    int i;
     //FIXME copy only needed parts
 //START_TIMER
     backup_duplicate_context(&bak, dst);
     memcpy(dst, src, sizeof(MpegEncContext));
     backup_duplicate_context(dst, &bak);
+    for(i=0;i<12;i++){
+        dst->pblocks[i] = (short *)(&dst->block[i]);
+    }
 //STOP_TIMER("update_duplicate_context") //about 10k cycles / 0.01 sec for 1000frames on 1ghz with 2 threads
 }
 
@@ -4632,7 +4636,7 @@ static void encode_picture(MpegEncContext *s, int picture_number)
     
     s->mb_intra=0; //for the rate distoration & bit compare functions
     for(i=1; i<s->avctx->thread_count; i++){
-        update_duplicate_context(s->thread_context[i], s);
+        ff_update_duplicate_context(s->thread_context[i], s);
     }
     
     /* Estimate motion for every MB */

libavcodec/mpegvideo.h

@@ -736,6 +736,7 @@ void ff_print_debug_info(MpegEncContext *s, AVFrame *pict);
 void ff_write_quant_matrix(PutBitContext *pb, int16_t *matrix);
 int ff_find_unused_picture(MpegEncContext *s, int shared);
 void ff_denoise_dct(MpegEncContext *s, DCTELEM *block);
+void ff_update_duplicate_context(MpegEncContext *dst, MpegEncContext *src);
 
 void ff_er_frame_start(MpegEncContext *s);
 void ff_er_frame_end(MpegEncContext *s);