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gst/mpegaudioparse/gstmpegaudioparse.c: Interpolate the VBRI seek table entries to get better results, support 3 byte...

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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.
This commit is contained in:
Sebastian Dröge 2008-01-15 17:18:31 +00:00
parent 7b5d4c287e
commit eecdae5af2
3 changed files with 61 additions and 19 deletions
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10
ChangeLog
View file

@ -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),

2
common

@ -1 +1 @@
Subproject commit 36e8d05157d6c831e0d3919ae2ee9c342498eda8
Subproject commit 0efbab89d333b5d07cc7da1a501c38edf5bb4f72

68
gst/mpegaudioparse/gstmpegaudioparse.c
View file

@ -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);
gint i, j;
gdouble a, b, fa, fb;
i = CLAMP (i, 0, mp3parse->vbri_seek_points);
i = gst_util_uint64_scale (ts, mp3parse->vbri_seek_points - 1, total_time);
i = CLAMP (i, 0, mp3parse->vbri_seek_points - 1);
*bytepos = mp3parse->vbri_seek_table[i];
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 = 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)
do {
sum += mp3parse->vbri_seek_table[i];
i++;
} while (i + 1 < mp3parse->vbri_seek_points
&& sum + mp3parse->vbri_seek_table[i] < bytepos);
i--;
i = CLAMP (i, 0, mp3parse->vbri_seek_points);
a = gst_guint64_to_gdouble (sum);
fa = gst_guint64_to_gdouble (gst_util_uint64_scale (i, total_time,
mp3parse->vbri_seek_points));
*ts = gst_util_uint64_scale (total_time, i, 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_gdouble_to_guint64 (fa + ((fb - fa) / (b - a)) * (bytepos - a));
return TRUE;
}