gst/mpegaudioparse/gstmpegaudioparse.c: Interpolate the VBRI seek table entries to...

Original commit message from CVS:
* gst/mpegaudioparse/gstmpegaudioparse.c:
(gst_mp3parse_handle_first_frame), (mp3parse_time_to_bytepos),
(mp3parse_bytepos_to_time):
Interpolate the VBRI seek table entries to get better results,
support 3 byte seek table entries and prevent overflows in the
seek table by adding the relative offsets when using the seek
table in a large enough data type.

diff --git a/ChangeLog b/ChangeLog
index 8bbe143..47e6d37 100644 (file)
--- a/ChangeLog
+++ b/ChangeLog
@@ -1,3 +1,13 @@
+2008-01-15  Sebastian Dröge  <slomo@circular-chaos.org>
+
+       * gst/mpegaudioparse/gstmpegaudioparse.c:
+       (gst_mp3parse_handle_first_frame), (mp3parse_time_to_bytepos),
+       (mp3parse_bytepos_to_time):
+       Interpolate the VBRI seek table entries to get better results,
+       support 3 byte seek table entries and prevent overflows in the
+       seek table by adding the relative offsets when using the seek
+       table in a large enough data type.
+
 2008-01-14  Sebastian Dröge  <slomo@circular-chaos.org>
 
        * gst/mpegaudioparse/gstmpegaudioparse.c: (gst_mp3parse_reset),

diff --git a/common b/common
index 36e8d05..0efbab8 160000 (submodule)
--- a/common
+++ b/common
@@ -1 +1 @@
-Subproject commit 36e8d05157d6c831e0d3919ae2ee9c342498eda8
+Subproject commit 0efbab89d333b5d07cc7da1a501c38edf5bb4f72

diff --git a/gst/mpegaudioparse/gstmpegaudioparse.c b/gst/mpegaudioparse/gstmpegaudioparse.c
index b0fa5a3..b6360cf 100644 (file)
--- a/gst/mpegaudioparse/gstmpegaudioparse.c
+++ b/gst/mpegaudioparse/gstmpegaudioparse.c
@@ -29,6 +29,7 @@
 GST_DEBUG_CATEGORY_STATIC (mp3parse_debug);
 #define GST_CAT_DEFAULT mp3parse_debug
 
+#define GST_READ_UINT24_BE(p) (p[2] | (p[1] << 8) | (p[0] << 16))
 
 /* elementfactory information */
 static GstElementDetails mp3parse_details = {
@@ -922,8 +923,7 @@ gst_mp3parse_handle_first_frame (GstMPEGAudioParse * mp3parse)
       seek_frames = GST_READ_UINT16_BE (data);
       data += 2;
 
-      if (scale == 0 || seek_bytes == 0 || seek_bytes == 3 || seek_bytes > 4
-          || seek_frames == 0) {
+      if (scale == 0 || seek_bytes == 0 || seek_bytes > 4 || seek_frames == 0) {
         GST_WARNING_OBJECT (mp3parse, "Unsupported VBRI seek table");
         goto out_vbri;
       }
@@ -952,21 +952,19 @@ gst_mp3parse_handle_first_frame (GstMPEGAudioParse * mp3parse)
       mp3parse->vbri_seek_table = g_new (guint32, nseek_points);
       if (seek_bytes == 4)
         for (i = 0; i < nseek_points; i++) {
-          mp3parse->vbri_seek_table[i] =
-              (i > 0) ? mp3parse->vbri_seek_table[i - 1] : 0;
-          mp3parse->vbri_seek_table[i] += GST_READ_UINT32_BE (data) * scale;
+          mp3parse->vbri_seek_table[i] = GST_READ_UINT32_BE (data) * scale;
           data += 4;
+      } else if (seek_bytes == 3)
+        for (i = 0; i < nseek_points; i++) {
+          mp3parse->vbri_seek_table[i] = GST_READ_UINT24_BE (data) * scale;
+          data += 3;
       } else if (seek_bytes == 2)
         for (i = 0; i < nseek_points; i++) {
-          mp3parse->vbri_seek_table[i] =
-              (i > 0) ? mp3parse->vbri_seek_table[i - 1] : 0;
-          mp3parse->vbri_seek_table[i] += GST_READ_UINT16_BE (data) * scale;
+          mp3parse->vbri_seek_table[i] = GST_READ_UINT16_BE (data) * scale;
           data += 2;
       } else                    /* seek_bytes == 1 */
         for (i = 0; i < nseek_points; i++) {
-          mp3parse->vbri_seek_table[i] =
-              (i > 0) ? mp3parse->vbri_seek_table[i - 1] : 0;
-          mp3parse->vbri_seek_table[i] += GST_READ_UINT8 (data) * scale;
+          mp3parse->vbri_seek_table[i] = GST_READ_UINT8 (data) * scale;
           data += 1;
         }
     }
@@ -1371,11 +1369,28 @@ mp3parse_time_to_bytepos (GstMPEGAudioParse * mp3parse, GstClockTime ts,
   if (mp3parse->vbri_seek_table &&
       mp3parse_total_bytes (mp3parse, &total_bytes) &&
       mp3parse_total_time (mp3parse, &total_time)) {
-    gint i = gst_util_uint64_scale (ts, mp3parse->vbri_seek_points, total_time);
-
-    i = CLAMP (i, 0, mp3parse->vbri_seek_points);
+    gint i, j;
+    gdouble a, b, fa, fb;
+
+    i = gst_util_uint64_scale (ts, mp3parse->vbri_seek_points - 1, total_time);
+    i = CLAMP (i, 0, mp3parse->vbri_seek_points - 1);
+
+    a = gst_guint64_to_gdouble (gst_util_uint64_scale (i, total_time,
+            mp3parse->vbri_seek_points));
+    fa = 0.0;
+    for (j = i; j >= 0; j--)
+      fa += mp3parse->vbri_seek_table[j];
+
+    if (i + 1 < mp3parse->vbri_seek_points) {
+      b = gst_guint64_to_gdouble (gst_util_uint64_scale (i + 1, total_time,
+              mp3parse->vbri_seek_points));
+      fb = fa + mp3parse->vbri_seek_table[i + 1];
+    } else {
+      b = gst_guint64_to_gdouble (total_time);
+      fb = total_bytes;
+    }
 
-    *bytepos = mp3parse->vbri_seek_table[i];
+    *bytepos = fa + ((fb - fa) / (b - a)) * (ts - a);
 
     return TRUE;
   }
@@ -1433,14 +1448,31 @@ mp3parse_bytepos_to_time (GstMPEGAudioParse * mp3parse,
       mp3parse_total_bytes (mp3parse, &total_bytes) &&
       mp3parse_total_time (mp3parse, &total_time)) {
     gint i = 0;
+    guint64 sum = 0;
+    gdouble a, b, fa, fb;
 
-    while (mp3parse->vbri_seek_table[i] < bytepos
-        && i < mp3parse->vbri_seek_points)
-      i++;
 
-    i = CLAMP (i, 0, mp3parse->vbri_seek_points);
+    do {
+      sum += mp3parse->vbri_seek_table[i];
+      i++;
+    } while (i + 1 < mp3parse->vbri_seek_points
+        && sum + mp3parse->vbri_seek_table[i] < bytepos);
+    i--;
+
+    a = gst_guint64_to_gdouble (sum);
+    fa = gst_guint64_to_gdouble (gst_util_uint64_scale (i, total_time,
+            mp3parse->vbri_seek_points));
+
+    if (i + 1 < mp3parse->vbri_seek_points) {
+      b = a + mp3parse->vbri_seek_table[i + 1];
+      fb = gst_guint64_to_gdouble (gst_util_uint64_scale (i + 1, total_time,
+              mp3parse->vbri_seek_points));
+    } else {
+      b = total_bytes;
+      fb = gst_guint64_to_gdouble (total_time);
+    }
 
-    *ts = gst_util_uint64_scale (total_time, i, mp3parse->vbri_seek_points);
+    *ts = gst_gdouble_to_guint64 (fa + ((fb - fa) / (b - a)) * (bytepos - a));
 
     return TRUE;
   }