1 /* -*- Mode: C; tab-width: 2; indent-tabs-mode: t; c-basic-offset: 2 -*- */
2 /* GStreamer ID3 tag demuxer
3 * Copyright (C) 2005 Jan Schmidt <thaytan@mad.scientist.com>
4 * Copyright (C) 2003-2004 Benjamin Otte <otte@gnome.org>
6 * This library is free software; you can redistribute it and/or
7 * modify it under the terms of the GNU Library General Public
8 * License as published by the Free Software Foundation; either
9 * version 2 of the License, or (at your option) any later version.
11 * This library is distributed in the hope that it will be useful,
12 * but WITHOUT ANY WARRANTY; without even the implied warranty of
13 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
14 * Library General Public License for more details.
16 * You should have received a copy of the GNU Library General Public
17 * License along with this library; if not, write to the
18 * Free Software Foundation, Inc., 59 Temple Place - Suite 330,
19 * Boston, MA 02111-1307, USA.
23 * SECTION:element-id3demux
25 * id3demux accepts data streams with either (or both) ID3v2 regions at the
26 * start, or ID3v1 at the end. The mime type of the data between the tag blocks
27 * is detected using typefind functions, and the appropriate output mime type
28 * set on outgoing buffers.
30 * The element is only able to read ID3v1 tags from a seekable stream, because
31 * they are at the end of the stream. That is, when get_range mode is supported
32 * by the upstream elements. If get_range operation is available, id3demux makes
33 * it available downstream. This means that elements which require get_range
34 * mode, such as wavparse, can operate on files containing ID3 tag information.
36 * This id3demux element replaced an older element with the same name which
37 * relied on libid3tag from the MAD project.
40 * <title>Example launch line</title>
42 * gst-launch filesrc location=file.mp3 ! id3demux ! fakesink -t
43 * ]| This pipeline should read any available ID3 tag information and output it.
44 * The contents of the file inside the ID3 tag regions should be detected, and
45 * the appropriate mime type set on buffers produced from id3demux.
52 #include <gst/gst-i18n-plugin.h>
53 #include <gst/tag/tag.h>
54 #include <gst/pbutils/pbutils.h>
57 #include "gstid3demux.h"
65 #define DEFAULT_PREFER_V1 FALSE
67 GST_DEBUG_CATEGORY (id3demux_debug);
68 #define GST_CAT_DEFAULT (id3demux_debug)
70 #define ID3V1_TAG_SIZE 128
71 #define ID3V2_HDR_SIZE GST_TAG_ID3V2_HEADER_SIZE
73 static GstStaticPadTemplate sink_factory = GST_STATIC_PAD_TEMPLATE ("sink",
76 GST_STATIC_CAPS ("application/x-id3")
79 static gboolean gst_id3demux_identify_tag (GstTagDemux * demux,
80 GstBuffer * buffer, gboolean start_tag, guint * tag_size);
81 static GstTagDemuxResult gst_id3demux_parse_tag (GstTagDemux * demux,
82 GstBuffer * buffer, gboolean start_tag, guint * tag_size,
84 static GstTagList *gst_id3demux_merge_tags (GstTagDemux * tagdemux,
85 const GstTagList * start_tags, const GstTagList * end_tags);
87 static void gst_id3demux_set_property (GObject * object, guint prop_id,
88 const GValue * value, GParamSpec * pspec);
89 static void gst_id3demux_get_property (GObject * object, guint prop_id,
90 GValue * value, GParamSpec * pspec);
92 #define gst_id3demux_parent_class parent_class
93 G_DEFINE_TYPE (GstID3Demux, gst_id3demux, GST_TYPE_TAG_DEMUX);
96 gst_id3demux_class_init (GstID3DemuxClass * klass)
98 GObjectClass *gobject_class = (GObjectClass *) klass;
99 GstElementClass *gstelement_class = (GstElementClass *) klass;
100 GstTagDemuxClass *tagdemux_class = (GstTagDemuxClass *) klass;
102 gobject_class->set_property = gst_id3demux_set_property;
103 gobject_class->get_property = gst_id3demux_get_property;
105 g_object_class_install_property (gobject_class, ARG_PREFER_V1,
106 g_param_spec_boolean ("prefer-v1", "Prefer version 1 tag",
107 "Prefer tags from ID3v1 tag at end of file when both ID3v1 "
108 "and ID3v2 tags are present", DEFAULT_PREFER_V1,
109 G_PARAM_READWRITE | G_PARAM_CONSTRUCT | G_PARAM_STATIC_STRINGS));
111 gst_element_class_add_pad_template (gstelement_class,
112 gst_static_pad_template_get (&sink_factory));
114 gst_element_class_set_static_metadata (gstelement_class, "ID3 tag demuxer",
115 "Codec/Demuxer/Metadata",
116 "Read and output ID3v1 and ID3v2 tags while demuxing the contents",
117 "Jan Schmidt <thaytan@mad.scientist.com>");
119 tagdemux_class->identify_tag = GST_DEBUG_FUNCPTR (gst_id3demux_identify_tag);
120 tagdemux_class->parse_tag = GST_DEBUG_FUNCPTR (gst_id3demux_parse_tag);
121 tagdemux_class->merge_tags = GST_DEBUG_FUNCPTR (gst_id3demux_merge_tags);
123 tagdemux_class->min_start_size = ID3V2_HDR_SIZE;
124 tagdemux_class->min_end_size = ID3V1_TAG_SIZE;
128 gst_id3demux_init (GstID3Demux * id3demux)
130 id3demux->prefer_v1 = DEFAULT_PREFER_V1;
134 gst_id3demux_identify_tag (GstTagDemux * demux, GstBuffer * buf,
135 gboolean start_tag, guint * tag_size)
139 gst_buffer_extract (buf, 0, data, 3);
142 if (data[0] != 'I' || data[1] != 'D' || data[2] != '3')
145 *tag_size = gst_tag_get_id3v2_tag_size (buf);
147 if (data[0] != 'T' || data[1] != 'A' || data[2] != 'G')
150 *tag_size = ID3V1_TAG_SIZE;
153 GST_INFO_OBJECT (demux, "Found ID3v%u marker, tag_size = %u",
154 (start_tag) ? 2 : 1, *tag_size);
160 GST_DEBUG_OBJECT (demux, "No ID3v%u marker found", (start_tag) ? 2 : 1);
166 gst_id3demux_add_container_format (GstTagList * tags)
170 sink_caps = gst_static_pad_template_get_caps (&sink_factory);
171 gst_pb_utils_add_codec_description_to_tag_list (tags,
172 GST_TAG_CONTAINER_FORMAT, sink_caps);
173 gst_caps_unref (sink_caps);
176 static GstTagDemuxResult
177 gst_id3demux_parse_tag (GstTagDemux * demux, GstBuffer * buffer,
178 gboolean start_tag, guint * tag_size, GstTagList ** tags)
181 *tag_size = gst_tag_get_id3v2_tag_size (buffer);
182 *tags = gst_tag_list_from_id3v2_tag (buffer);
184 if (G_LIKELY (*tags != NULL)) {
185 gst_id3demux_add_container_format (*tags);
186 return GST_TAG_DEMUX_RESULT_OK;
188 return GST_TAG_DEMUX_RESULT_BROKEN_TAG;
193 gst_buffer_map (buffer, &map, GST_MAP_READ);
194 *tags = gst_tag_list_new_from_id3v1 (map.data);
195 gst_buffer_unmap (buffer, &map);
197 if (G_UNLIKELY (*tags == NULL))
198 return GST_TAG_DEMUX_RESULT_BROKEN_TAG;
200 gst_id3demux_add_container_format (*tags);
201 *tag_size = ID3V1_TAG_SIZE;
202 return GST_TAG_DEMUX_RESULT_OK;
207 gst_id3demux_merge_tags (GstTagDemux * tagdemux, const GstTagList * start_tags,
208 const GstTagList * end_tags)
210 GstID3Demux *id3demux;
214 id3demux = GST_ID3DEMUX (tagdemux);
216 GST_OBJECT_LOCK (id3demux);
217 prefer_v1 = id3demux->prefer_v1;
218 GST_OBJECT_UNLOCK (id3demux);
220 /* we merge in REPLACE mode, so put the less important tags first */
222 merged = gst_tag_list_merge (start_tags, end_tags, GST_TAG_MERGE_REPLACE);
224 merged = gst_tag_list_merge (end_tags, start_tags, GST_TAG_MERGE_REPLACE);
226 GST_LOG_OBJECT (id3demux, "start tags: %" GST_PTR_FORMAT, start_tags);
227 GST_LOG_OBJECT (id3demux, "end tags: %" GST_PTR_FORMAT, end_tags);
228 GST_LOG_OBJECT (id3demux, "merged tags: %" GST_PTR_FORMAT, merged);
234 gst_id3demux_set_property (GObject * object, guint prop_id,
235 const GValue * value, GParamSpec * pspec)
237 GstID3Demux *id3demux;
239 id3demux = GST_ID3DEMUX (object);
243 GST_OBJECT_LOCK (id3demux);
244 id3demux->prefer_v1 = g_value_get_boolean (value);
245 GST_OBJECT_UNLOCK (id3demux);
249 G_OBJECT_WARN_INVALID_PROPERTY_ID (object, prop_id, pspec);
255 gst_id3demux_get_property (GObject * object, guint prop_id,
256 GValue * value, GParamSpec * pspec)
258 GstID3Demux *id3demux;
260 id3demux = GST_ID3DEMUX (object);
264 GST_OBJECT_LOCK (id3demux);
265 g_value_set_boolean (value, id3demux->prefer_v1);
266 GST_OBJECT_UNLOCK (id3demux);
269 G_OBJECT_WARN_INVALID_PROPERTY_ID (object, prop_id, pspec);
275 plugin_init (GstPlugin * plugin)
277 GST_DEBUG_CATEGORY_INIT (id3demux_debug, "id3demux", 0,
278 "GStreamer ID3 tag demuxer");
280 gst_tag_register_musicbrainz_tags ();
282 return gst_element_register (plugin, "id3demux",
283 GST_RANK_PRIMARY, GST_TYPE_ID3DEMUX);
286 GST_PLUGIN_DEFINE (GST_VERSION_MAJOR,
289 "Demux ID3v1 and ID3v2 tags from a file",
290 plugin_init, VERSION, GST_LICENSE, GST_PACKAGE_NAME, GST_PACKAGE_ORIGIN)