[gegl/video-rejuvenation: 15/30] examples/gegl-video: add jit SDL audio output

[Øyvind Kolås <ok src gnome org>]

commit e123cf5db241fea9dda789e4e1515290c1d5376c
Author: Øyvind Kolås <pippin gimp org>
Date:   Fri Oct 9 20:09:05 2015 +0200

    examples/gegl-video: add jit SDL audio output

 examples/Makefile.am          |    3 +-
 examples/gegl-video.c         |   79 ++++++++++++++++++++++++++++++++++++++---
 operations/external/ff-load.c |    2 +-
 3 files changed, 77 insertions(+), 7 deletions(-)
---
diff --git a/examples/Makefile.am b/examples/Makefile.am
index b10add8..edc1186 100644
--- a/examples/Makefile.am
+++ b/examples/Makefile.am
@@ -22,13 +22,14 @@ AM_CPPFLAGS = \
        -I$(top_builddir)/gegl/property-types \
        -I$(top_srcdir)/gegl/property-types
 
-AM_CFLAGS = $(DEP_CFLAGS) $(BABL_CFLAGS) $(GEXIV2_CFLAGS)
+AM_CFLAGS = $(DEP_CFLAGS) $(BABL_CFLAGS) $(GEXIV2_CFLAGS) $(SDL_CFLAGS)
 
 AM_LDFLAGS =  \
        $(top_builddir)/gegl/libgegl-$(GEGL_API_VERSION).la \
        $(GEXIV2_LIBS) \
        $(BABL_LIBS) \
        $(DEP_LIBS) \
+       $(SDL_LIBS) \
        $(MATH_LIB)
 
 bin_PROGRAMS = \
diff --git a/examples/gegl-video.c b/examples/gegl-video.c
index 6c32bf5..44d861f 100644
--- a/examples/gegl-video.c
+++ b/examples/gegl-video.c
@@ -27,6 +27,7 @@
 #include <stdlib.h>
 #include <string.h>
 #include <math.h>
+#include <SDL.h>
 
 typedef enum NeglRunMode {
   NEGL_NO_UI = 0,
@@ -137,7 +138,6 @@ static void parse_args (int argc, char **argv)
       stage = 1;
     } 
   }
-
 }
 
 GeglNode   *gegl_decode  = NULL;
@@ -162,13 +162,53 @@ static void decode_frame_no (int frame)
 
 GeglNode *translate = NULL;
 
+static int audio_len = 0;
+static int audio_pos = 0;
+
+int16_t audio_data[8192000];
+
+
+static void fill_audio(void *udata, Uint8 *stream, int len)
+{
+  int audio_remaining = audio_len - audio_pos;
+  if (audio_remaining < 0)
+    return;
+
+  if (audio_remaining < len) len = audio_remaining;
+
+  //SDL_MixAudio(stream, (uint8_t*)&audio_data[audio_pos/2], len, SDL_MIX_MAXVOLUME);
+  memcpy (stream, (uint8_t*)&audio_data[audio_pos/2], len);
+  audio_pos += len;
+}
+
+static int audio_started = 0;
+
 gint
 main (gint    argc,
       gchar **argv)
 {
+  SDL_AudioSpec AudioSettings = {0};
+
   GeglNode *display = NULL;
   GeglNode *readbuf = NULL;
 
+  SDL_Init(SDL_INIT_AUDIO);
+  AudioSettings.freq = 48000;
+  AudioSettings.format = AUDIO_S16SYS;
+  AudioSettings.channels = 2;
+  AudioSettings.samples = 1024;
+  AudioSettings.callback = fill_audio;
+  SDL_OpenAudio(&AudioSettings, 0);
+
+  if (AudioSettings.format != AUDIO_S16SYS)
+   {
+      fprintf (stderr, "not getting format we wanted\n");
+   }
+  if (AudioSettings.freq != 48000)
+   {
+      fprintf (stderr, "not getting rate we wanted\n");
+   }
+
   if (argc < 2)
     usage();
 
@@ -234,14 +274,42 @@ main (gint    argc,
         }
 
        decode_frame_no (frame);
+        {
+        GeglAudio *audio;
+        gdouble fps;
+        gegl_node_get (load, "audio", &audio,
+                             "frame-rate", &fps, NULL);
+
+
+
+        if (audio->samples > 0)
+        {
+          int i;
+          if (!audio_started)
+           {
+             SDL_PauseAudio(0);
+             audio_started = 1;
+           }
+          for (i = 0; i < audio->samples; i++)
+          {
+            audio_data[audio_len/2 + 0] = audio->left[i] * 32767.0;
+            audio_data[audio_len/2 + 1] = audio->right[i] * 32767.0;
+            audio_len += 4;
+          }
+        }
 
         switch(run_mode)
         {
           case NEGL_NO_UI:
             break;
           case NEGL_VIDEO:
+
            gegl_node_set (readbuf, "buffer", video_frame, NULL);
            gegl_node_process (display);
+           while ( (audio_pos / 4.0) / audio->samplerate < (frame / fps) - 0.05 )
+            {
+              g_usleep (500); /* sync audio */
+            }
             break;
         }
 
@@ -250,19 +318,18 @@ main (gint    argc,
           char *path = g_strdup_printf ("%s%07i%s", frame_path, output_frame_no++, frame_extension);
          GeglNode *save_graph = gegl_node_new ();
          GeglNode *readbuf, *save;
-          GeglAudio *audio;
-          gegl_node_get (load, "audio", &audio, NULL);
      
          readbuf = gegl_node_new_child (save_graph, "operation", "gegl:buffer-source", "buffer", 
video_frame, NULL);
-         save = gegl_node_new_child (save_graph, "operation", "gegl:png-save", "bitdepth", 8, "compression", 
2,
+         save = gegl_node_new_child (save_graph, "operation", "gegl:save",
            "path", path, NULL);
            gegl_node_link_many (readbuf, save, NULL);
          gegl_node_process (save);
          g_object_unref (save_graph);
           gegl_meta_set_audio (path, audio);
           g_free (path);
-          g_object_unref (audio);
        }
+        g_object_unref (audio);
+        }
 
       }
       if (show_progress)
@@ -312,6 +379,8 @@ gegl_meta_set_audio (const char *path,
     g_string_free (str, TRUE);
   }
   gexiv2_metadata_free (e2m);
+
+  SDL_CloseAudio();
 }
 
 void
diff --git a/operations/external/ff-load.c b/operations/external/ff-load.c
index dad5844..61a6888 100644
--- a/operations/external/ff-load.c
+++ b/operations/external/ff-load.c
@@ -82,7 +82,7 @@ typedef struct
   glong            prevframe;      /* previously decoded frame in loadedfile */
 } Priv;
 
-typedef struct AudioFrame {     /* XXX: hardcoded for 16bit chunky stereo, */
+typedef struct AudioFrame {        /* XXX: hardcoded for 16bit chunky stereo, */
   uint8_t          buf[16000]; 
   int              len;
   long             pos;