[xiph-commits] r9148 - experimental/giles/theora-exp-mt/examples
giles at motherfish-iii.xiph.org
giles at motherfish-iii.xiph.org
Sun Apr 17 00:39:36 PDT 2005
Author: giles
Date: 2005-04-17 00:39:35 -0700 (Sun, 17 Apr 2005)
New Revision: 9148
Modified:
experimental/giles/theora-exp-mt/examples/player_example.c
Log:
Improve multithreading in the example player. We now use separate
threads to handle the copy of the stripe data as it becomes available,
and to show the final completely frame. This is a modest increase in
parallelism.
Also, use condition variables to signal the worker threads instead
of the earlier scheme relying only on the mutex unlock.
Modified: experimental/giles/theora-exp-mt/examples/player_example.c
===================================================================
--- experimental/giles/theora-exp-mt/examples/player_example.c 2005-04-17 04:53:39 UTC (rev 9147)
+++ experimental/giles/theora-exp-mt/examples/player_example.c 2005-04-17 07:39:35 UTC (rev 9148)
@@ -81,6 +81,7 @@
}
/* never forget that globals are a one-way ticket to Hell */
+/* once you start, you'll just add more and more... */
/* Ogg and codec state for demux/decode */
ogg_sync_state oy;
ogg_page og;
@@ -109,8 +110,20 @@
int videobuf_ready=0;
ogg_int64_t videobuf_granulepos=-1;
double videobuf_time=0;
+
#ifdef HAVE_PTHREAD
-pthread_mutex_t videobuf_mutex; /* clear when ready to show a frame */
+/* background stripe copy thread */
+pthread_t stripe_copy_thread;
+pthread_mutex_t stripe_mutex;
+pthread_cond_t stripe_ready_cond;
+int stripe_fragy0 = 0;
+int stripe_fragy_end = 0;
+theora_ycbcr_buffer videobuf_src;
+
+/* background frame display thread */
+pthread_t video_display_thread;
+pthread_mutex_t videobuf_mutex;
+pthread_cond_t videobuf_ready_cond;
#endif
/* single audio fragment audio buffering */
@@ -336,25 +349,48 @@
}
#ifdef HAVE_PTHREAD
+static void video_stripe_mark(void *_ctx, theora_ycbcr_buffer _src,
+ int _fragy0, int _fragy_end){
+ /* mark data stripe as available */
+ pthread_mutex_lock(&stripe_mutex);
+ memcpy(videobuf_src, _src, sizeof(theora_ycbcr_buffer));
+ stripe_fragy0 = _fragy0;
+ stripe_fragy_end = _fragy_end;
+
+ /* notify data copy thread */
+ pthread_cond_signal(&stripe_ready_cond);
+ pthread_mutex_unlock(&stripe_mutex);
+}
+
+/* loop, copying decoded data to the overlay */
static void *video_write_loop(void *arg){
- int min_delay = 1000.0 * ti.fps_denominator/ti.fps_numerator;
while(1){
- /* wait until a frame is ready */
- pthread_mutex_lock(&videobuf_mutex);
- if(videobuf_ready){
- /* Show, baby, show! */
- SDL_DisplayYUVOverlay(yuv_overlay, &rect);
- videobuf_ready=0;
- pthread_mutex_unlock(&videobuf_mutex);
- }else{
- pthread_mutex_unlock(&videobuf_mutex);
- SDL_Delay(min_delay);
- }
+ pthread_mutex_lock(&stripe_mutex);
+ /* wait until stripe data is ready */
+ pthread_cond_wait(&stripe_ready_cond, &stripe_mutex);
+ video_stripe_copy(NULL, videobuf_src, stripe_fragy0, stripe_fragy_end);
+ pthread_mutex_unlock(&stripe_mutex);
}
return NULL;
}
-#endif
+/* loop, showing the current frame when we get a signal */
+static void *video_display_loop(void *arg){
+ pthread_mutex_lock(&videobuf_mutex);
+ while (!videobuf_ready) {
+ pthread_cond_wait(&videobuf_ready_cond, &videobuf_mutex);
+ /* we could lock stripe_mutex here too, to make sure the
+ video write thread isn't active, but the way we're
+ called from outside theora_decode_packetin() makes that
+ unnecessary */
+ SDL_DisplayYUVOverlay(yuv_overlay, &rect);
+ videobuf_ready = 0;
+ }
+ pthread_mutex_unlock(&videobuf_mutex);
+ return NULL;
+}
+#endif /* HAVE_PTHREAD */
+
static void open_video(void){
theora_stripe_callback cb;
@@ -383,14 +419,32 @@
rect.w = ti.pic_width;
rect.h = ti.pic_height;
+ /* initialize video playback threads */
+#ifdef HAVE_PTHREAD
+ /* spawn the display loop */
+ pthread_mutex_init(&videobuf_mutex, NULL);
+ pthread_cond_init(&videobuf_ready_cond, NULL);
+ pthread_create(&video_display_thread, NULL, video_display_loop, NULL);
+ /* spawn the stripe-copy loop */
+ pthread_mutex_init(&stripe_mutex, NULL);
+ pthread_cond_init(&stripe_ready_cond, NULL);
+ pthread_create(&stripe_copy_thread, NULL, video_write_loop, NULL);
/* install stripe callback */
cb.ctx = yuv_overlay;
+ cb.stripe_decoded=(theora_stripe_decoded_func)video_stripe_mark;
+ theora_decode_ctl(td,OC_DECCTL_SET_STRIPE_CB,&cb,sizeof(cb));
+#else
+ /* just copy stripe data directly in the callback */
+ cb.ctx = yuv_overlay;
cb.stripe_decoded=(theora_stripe_decoded_func)video_stripe_copy;
theora_decode_ctl(td,OC_DECCTL_SET_STRIPE_CB,&cb,sizeof(cb));
+#endif /* HAVE_PTHREAD */
SDL_DisplayYUVOverlay(yuv_overlay, &rect);
}
+/* Full frame copy and display. To use, set a null stripe callback
+ and call this instead after theora_decode_packetin() returns */
static void video_write(void){
static const int planemap[3] = {0,2,1};
int pli;
@@ -402,9 +456,6 @@
theora_decode_ycbcr_out(td,ycbcr);
/* Lock SDL_yuv_overlay */
- if ( SDL_MUSTLOCK(screen) ) {
- if ( SDL_LockSurface(screen) < 0 ) return;
- }
if (SDL_LockYUVOverlay(yuv_overlay) < 0) return;
/* let's draw the data on a SDL screen (*screen) */
@@ -426,16 +477,12 @@
}
/* Unlock SDL_yuv_overlay */
- if ( SDL_MUSTLOCK(screen) ) {
- SDL_UnlockSurface(screen);
- }
SDL_UnlockYUVOverlay(yuv_overlay);
-
/* Show, baby, show! */
SDL_DisplayYUVOverlay(yuv_overlay, &rect);
+}
-}
/* dump the theora (or vorbis) comment header */
static int dump_comments(theora_comment *tc){
int i, len;
@@ -512,10 +559,6 @@
int frames = 0;
int dropped = 0;
-#ifdef HAVE_PTHREAD
- pthread_t video_thread;
-#endif
-
#ifdef _WIN32 /* We need to set stdin/stdout to binary mode. Damn windows. */
/* Beware the evil ifdef. We avoid these where we can, but this one we
cannot. Don't add any more, you'll probably go to hell if you do. */
@@ -673,17 +716,6 @@
vorbis_comment_clear(&vc);
}
- /* initialize video playback thread */
-#ifdef HAVE_PTHREAD
- pthread_mutex_init(&videobuf_mutex, NULL);
- /* hold for a video frame */
- pthread_mutex_lock(&videobuf_mutex);
- videobuf_ready = 0;
- /* spawn the display loop */
- pthread_create(&video_thread, NULL, video_write_loop, NULL);
- pthread_mutex_unlock(&videobuf_mutex);
-#endif
-
/* open audio */
if(vorbis_p)open_audio();
@@ -773,7 +805,7 @@
#ifdef HAVE_PTHREAD
pthread_mutex_lock(&videobuf_mutex);
#endif
- videobuf_ready=1;
+ videobuf_ready=1;
}else{
/*If we are too slow, reduce the pp level.*/
pp_inc=pp_level>0?-1:0;
@@ -801,6 +833,8 @@
/* are we at or past time for this video frame? */
if(stateflag && videobuf_ready && videobuf_time<=get_time()){
#ifdef HAVE_PTHREAD
+ /* signal the display thread to show the frame */
+ pthread_cond_signal(&videobuf_ready_cond);
pthread_mutex_unlock(&videobuf_mutex);
#else
SDL_DisplayYUVOverlay(yuv_overlay, &rect);
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