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/* Gnome-Streamer
* Copyright (C) <1999> Erik Walthinsen <omega@cse.ogi.edu>
*
* This library is free software; you can redistribute it and/or
* modify it under the terms of the GNU Library General Public
* License as published by the Free Software Foundation; either
* version 2 of the License, or (at your option) any later version.
*
* This library is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
* Library General Public License for more details.
*
* You should have received a copy of the GNU Library General Public
* License along with this library; if not, write to the
* Free Software Foundation, Inc., 59 Temple Place - Suite 330,
* Boston, MA 02111-1307, USA.
*/
//#define DEBUG_ENABLED
#include <gst/gst.h>
#include <string.h> /* memcmp */
static GstCaps* mp3_typefind(GstBuffer *buf, gpointer private);
static GstTypeDefinition mp3type_definitions[] = {
{ "mp3types_audio/mp3", "audio/mp3", ".mp3 .mp2 .mp1 .mpga", mp3_typefind },
{ NULL, NULL, NULL, NULL },
};
static GstCaps*
mp3_typefind(GstBuffer *buf, gpointer private)
{
gchar *data;
gulong head;
GstCaps *caps;
data = GST_BUFFER_DATA(buf);
GST_DEBUG (0,"mp3typefind: typefind\n");
/* check for ID3 Tag first and forward ID3 length */
if (!memcmp (data, "ID3", 3))
{
guint32 skip;
/* ignore next 3 bytes */
data += 6;
/* if you want that thing faster, do it */
skip = GUINT32_FROM_BE(*((guint32 *)data));
skip = (((skip & 0x7f000000) >> 3) |
((skip & 0x007f0000) >> 2) |
((skip & 0x00007f00) >> 1) |
((skip & 0x0000007f) >> 0)) + 4;
GST_DEBUG (0, "mp3typefind: detected ID3 Tag with %u bytes\n", skip + 6);
/* return if buffer is not big enough */
if (GST_BUFFER_SIZE (buf) < skip + 10)
{
GST_DEBUG (0, "mp3typefind: buffer too small (%d) to go on typefinding\n", skip + 6);
return NULL;
}
data += skip;
}
/* now with the right postion, do typefinding */
head = GULONG_FROM_BE(*((gulong *)data));
if ((head & 0xffe00000) != 0xffe00000)
return NULL;
if (!((head >> 17) & 3))
return NULL;
if (((head >> 12) & 0xf) == 0xf)
return NULL;
if (!((head >> 12) & 0xf))
return NULL;
if (((head >> 10) & 0x3) == 0x3)
return NULL;
caps = gst_caps_new ("mp3_typefind", "audio/mp3", NULL);
/* gst_caps_set(caps,"layer",GST_PROPS_INT(4-((head>>17)&0x3))); */
return caps;
}
static gboolean
plugin_init (GModule *module, GstPlugin *plugin)
{
gint i=0;
while (mp3type_definitions[i].name) {
GstTypeFactory *type;
type = gst_typefactory_new (&mp3type_definitions[i]);
gst_plugin_add_feature (plugin, GST_PLUGIN_FEATURE (type));
i++;
}
/* gst_info("gsttypes: loaded %d mp3 types\n",i); */
return TRUE;
}
GstPluginDesc plugin_desc = {
GST_VERSION_MAJOR,
GST_VERSION_MINOR,
"mp3types",
plugin_init
};
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