Seeking support for AC3/A52 files. We assume they are always CBR.

git-svn-id: svn://svn.rockbox.org/rockbox/trunk@7650 a1c6a512-1295-4272-9138-f99709370657

3 files changed, 20 insertions, 5 deletions

diff --git a/apps/codecs/a52.c b/apps/codecs/a52.c
index fb881f8..e214cbb 100644
--- a/apps/codecs/a52.c
+++ b/apps/codecs/a52.c
@@ -24,6 +24,8 @@
 
 #define BUFFER_SIZE 4096
 
+#define A52_SAMPLESPERFRAME (6*256)
+
 struct codec_api *ci;
 
 static a52_state_t *state;
@@ -124,6 +126,7 @@ enum codec_status codec_start(struct codec_api *api)
 {
     long n;
     unsigned char *filebuf;
+    int sample_loc;
 
     /* Generic codec initialisation */
     TEST_CODEC_API(api);
@@ -160,6 +163,16 @@ next_track:
         if (ci->stop_codec || ci->reload_codec)
             break;
 
+        if (ci->seek_time) {
+            sample_loc = ci->seek_time/1000 * ci->id3->frequency;
+
+            if (ci->seek_buffer((sample_loc/A52_SAMPLESPERFRAME)*ci->id3->bytesperframe)) {
+                samplesdone = sample_loc;
+                ci->set_elapsed(samplesdone/(ci->id3->frequency/1000));
+            }
+            ci->seek_time = 0;
+        }
+
         filebuf = ci->request_buffer(&n, BUFFER_SIZE);
 
         if (n == 0) /* End of Stream */
diff --git a/apps/metadata.c b/apps/metadata.c
index f22e10d..d8aa120 100644
--- a/apps/metadata.c
+++ b/apps/metadata.c
@@ -1259,7 +1259,6 @@ bool get_metadata(struct track_info* track, int fd, const char* trackname,
 {
     unsigned char* buf;
     unsigned long totalsamples;
-    int bytesperframe;
     int i;
       
     /* Load codec specific track tag information. */
@@ -1381,17 +1380,17 @@ bool get_metadata(struct track_info* track, int fd, const char* trackname,
         {
         case 0x00: 
             track->id3.frequency = 48000; 
-            bytesperframe=track->id3.bitrate * 2 * 2;
+            track->id3.bytesperframe=track->id3.bitrate * 2 * 2;
             break;
             
         case 0x40: 
             track->id3.frequency = 44100;
-            bytesperframe = a52_441framesizes[i];
+            track->id3.bytesperframe = a52_441framesizes[i];
             break;
         
         case 0x80: 
             track->id3.frequency = 32000; 
-            bytesperframe = track->id3.bitrate * 3 * 2;
+            track->id3.bytesperframe = track->id3.bitrate * 3 * 2;
             break;
         
         default: 
@@ -1401,7 +1400,7 @@ bool get_metadata(struct track_info* track, int fd, const char* trackname,
         }
 
         /* One A52 frame contains 6 blocks, each containing 256 samples */
-        totalsamples = (track->filesize / bytesperframe) * 6 * 256;
+        totalsamples = (track->filesize / track->id3.bytesperframe) * 6 * 256;
         track->id3.length = (totalsamples / track->id3.frequency) * 1000;
         break;
 
diff --git a/firmware/export/id3.h b/firmware/export/id3.h
index deb6ba2..1e75353 100644
--- a/firmware/export/id3.h
+++ b/firmware/export/id3.h
@@ -82,6 +82,9 @@ struct mp3entry {
     /* MP3 stream specific info */
     unsigned long frame_count; /* number of frames in the file (if VBR) */
 
+    /* Used for A52/AC3 */
+    unsigned long bytesperframe; /* number of bytes per frame (if CBR) */
+
     /* Xing VBR fields */
     bool vbr;
     bool has_toc;           /* True if there is a VBR header in the file */