mpegaudioparse: Parse encoder delay and encoder padding from the LAME header if present

This commit is contained in:
Sebastian Dröge 2011-04-01 14:47:43 +02:00 committed by Tim-Philipp Müller
parent a1ec326204
commit f3a1dc9796
2 changed files with 36 additions and 0 deletions

View file

@ -214,6 +214,9 @@ gst_mpeg_audio_parse_reset (GstMpegAudioParse * mp3parse)
mp3parse->vbri_seek_points = 0;
g_free (mp3parse->vbri_seek_table);
mp3parse->vbri_seek_table = NULL;
mp3parse->encoder_delay = 0;
mp3parse->encoder_padding = 0;
}
static void
@ -558,6 +561,7 @@ gst_mpeg_audio_parse_handle_first_frame (GstMpegAudioParse * mp3parse,
const guint32 xing_id = 0x58696e67; /* 'Xing' in hex */
const guint32 info_id = 0x496e666f; /* 'Info' in hex - found in LAME CBR files */
const guint32 vbri_id = 0x56425249; /* 'VBRI' in hex */
const guint32 lame_id = 0x4c414d45; /* 'LAME' in hex */
gint offset;
guint64 avail;
gint64 upstream_total_bytes = 0;
@ -725,6 +729,7 @@ gst_mpeg_audio_parse_handle_first_frame (GstMpegAudioParse * mp3parse,
if (xing_flags & XING_VBR_SCALE_FLAG) {
mp3parse->xing_vbr_scale = GST_READ_UINT32_BE (data);
data += 4;
} else
mp3parse->xing_vbr_scale = 0;
@ -741,6 +746,33 @@ gst_mpeg_audio_parse_handle_first_frame (GstMpegAudioParse * mp3parse,
mp3parse->xing_flags &= ~XING_BYTES_FLAG;
mp3parse->xing_flags &= ~XING_FRAMES_FLAG;
}
/* Optional LAME tag? */
if (avail - bytes_needed >= 36 && GST_READ_UINT32_BE (data) == lame_id) {
gchar lame_version[10] = { 0, };
guint tag_rev;
guint32 encoder_delay, encoder_padding;
memcpy (lame_version, data, 9);
data += 9;
tag_rev = data[0] >> 4;
GST_DEBUG_OBJECT (mp3parse, "Found LAME tag revision %d created by '%s'",
tag_rev, lame_version);
/* Skip all the information we're not interested in */
data += 12;
/* Encoder delay and end padding */
encoder_delay = GST_READ_UINT24_BE (data);
encoder_delay >>= 12;
encoder_padding = GST_READ_UINT24_BE (data);
encoder_padding &= 0x000fff;
mp3parse->encoder_delay = encoder_delay;
mp3parse->encoder_padding = encoder_padding;
GST_DEBUG_OBJECT (mp3parse, "Encoder delay %u, encoder padding %u",
encoder_delay, encoder_padding);
}
} else if (read_id == vbri_id) {
gint64 total_bytes, total_frames;
GstClockTime total_time;

View file

@ -88,6 +88,10 @@ struct _GstMpegAudioParse {
guint vbri_seek_points;
guint32 *vbri_seek_table;
gboolean vbri_valid;
/* LAME info */
guint32 encoder_delay;
guint32 encoder_padding;
};
/**