typefinding: add AAC profile to ADTS caps

This looks at the AAC profile for ADTS streams and adds the profile as a
string in the corresponding caps.

Profile is the actual profile, base-profile denotes the minimum codec
requirements to decode this stream. In this case they're always the
same, but they may differ e.g. in case of certain HE-AAC streams that
can be partially decoded by LC decoders (with loss of quality of course)
if no suitable HE-AAC decoder is available.

Fixes #612312.
This commit is contained in:
Arun Raghavan 2010-03-10 13:32:53 +00:00 committed by Tim-Philipp Müller
parent 57cc1150a9
commit 34dcb8458e

View file

@ -650,6 +650,8 @@ static GstStaticCaps aac_caps = GST_STATIC_CAPS ("audio/mpeg, "
static void
aac_type_find (GstTypeFind * tf, gpointer unused)
{
/* LUT to convert the AudioObjectType from the ADTS header to a string */
static const gchar profile_to_string[][5] = { "main", "lc", "ssr", "ltp" };
DataScanCtx c = { 0, NULL, 0 };
while (c.offset < AAC_AMOUNT) {
@ -680,14 +682,17 @@ aac_type_find (GstTypeFind * tf, gpointer unused)
snc = GST_READ_UINT16_BE (c.data + len);
if ((snc & 0xfff6) == 0xfff0) {
gint mpegversion;
gint mpegversion, profile;
mpegversion = (c.data[1] & 0x08) ? 2 : 4;
profile = c.data[2] >> 6;
GST_DEBUG ("Found second ADTS-%d syncpoint at offset 0x%"
G_GINT64_MODIFIER "x, framelen %u", mpegversion, c.offset, len);
gst_type_find_suggest_simple (tf, GST_TYPE_FIND_LIKELY, "audio/mpeg",
"framed", G_TYPE_BOOLEAN, FALSE,
"mpegversion", G_TYPE_INT, mpegversion,
"base-profile", G_TYPE_STRING, profile_to_string[profile],
"profile", G_TYPE_STRING, profile_to_string[profile],
"stream-type", G_TYPE_STRING, "adts", NULL);
break;
}