2 * Copyright (C) 2008-2009 Sebastian Dröge <sebastian.droege@collabora.co.uk>
4 * This library is free software; you can redistribute it and/or
5 * modify it under the terms of the GNU Library General Public
6 * License as published by the Free Software Foundation; either
7 * version 2 of the License, or (at your option) any later version.
9 * This library is distributed in the hope that it will be useful,
10 * but WITHOUT ANY WARRANTY; without even the implied warranty of
11 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
12 * Library General Public License for more details.
14 * You should have received a copy of the GNU Library General Public
15 * License along with this library; if not, write to the
16 * Free Software Foundation, Inc., 51 Franklin St, Fifth Floor,
17 * Boston, MA 02110-1301, USA.
20 /* Implementation of SMPTE 388M - Mapping A-Law coded audio into the MXF
32 #include "mxfessence.h"
34 GST_DEBUG_CATEGORY_EXTERN (mxf_debug);
35 #define GST_CAT_DEFAULT mxf_debug
38 mxf_is_alaw_essence_track (const MXFMetadataTimelineTrack * track)
42 g_return_val_if_fail (track != NULL, FALSE);
44 if (track->parent.descriptor == NULL)
47 for (i = 0; i < track->parent.n_descriptor; i++) {
48 MXFMetadataFileDescriptor *d = track->parent.descriptor[i];
54 key = &d->essence_container;
56 if (mxf_is_generic_container_essence_container_label (key) &&
57 key->u[12] == 0x02 && key->u[13] == 0x0a &&
58 (key->u[14] == 0x01 || key->u[14] == 0x02 || key->u[14] == 0x03))
66 mxf_alaw_handle_essence_element (const MXFUL * key, GstBuffer * buffer,
68 MXFMetadataTimelineTrack * track,
69 gpointer mapping_data, GstBuffer ** outbuf)
74 if (key->u[12] != 0x16 || (key->u[14] != 0x08 && key->u[14] != 0x09
75 && key->u[14] != 0x0a)) {
76 GST_ERROR ("Invalid A-Law essence element");
77 return GST_FLOW_ERROR;
83 static MXFEssenceWrapping
84 mxf_alaw_get_track_wrapping (const MXFMetadataTimelineTrack * track)
88 g_return_val_if_fail (track != NULL, MXF_ESSENCE_WRAPPING_CUSTOM_WRAPPING);
90 if (track->parent.descriptor == NULL) {
91 GST_ERROR ("No descriptor found for this track");
92 return MXF_ESSENCE_WRAPPING_CUSTOM_WRAPPING;
95 for (i = 0; i < track->parent.n_descriptor; i++) {
96 if (!track->parent.descriptor[i])
99 if (!MXF_IS_METADATA_GENERIC_SOUND_ESSENCE_DESCRIPTOR (track->parent.
103 switch (track->parent.descriptor[i]->essence_container.u[14]) {
105 return MXF_ESSENCE_WRAPPING_FRAME_WRAPPING;
108 return MXF_ESSENCE_WRAPPING_CLIP_WRAPPING;
112 return MXF_ESSENCE_WRAPPING_CUSTOM_WRAPPING;
117 return MXF_ESSENCE_WRAPPING_CUSTOM_WRAPPING;
121 mxf_alaw_create_caps (MXFMetadataTimelineTrack * track, GstTagList ** tags,
122 gboolean * intra_only, MXFEssenceElementHandleFunc * handler,
123 gpointer * mapping_data)
125 MXFMetadataGenericSoundEssenceDescriptor *s = NULL;
127 GstCaps *caps = NULL;
129 g_return_val_if_fail (track != NULL, NULL);
131 if (track->parent.descriptor == NULL) {
132 GST_ERROR ("No descriptor found for this track");
136 for (i = 0; i < track->parent.n_descriptor; i++) {
137 if (!track->parent.descriptor[i])
140 if (MXF_IS_METADATA_GENERIC_SOUND_ESSENCE_DESCRIPTOR (track->parent.
142 s = (MXFMetadataGenericSoundEssenceDescriptor *) track->parent.
149 GST_ERROR ("No generic sound essence descriptor found for this track");
153 *handler = mxf_alaw_handle_essence_element;
155 if (s && s->audio_sampling_rate.n != 0 && s->audio_sampling_rate.d != 0 &&
156 s->channel_count != 0) {
158 caps = gst_caps_new_empty_simple ("audio/x-alaw");
159 mxf_metadata_generic_sound_essence_descriptor_set_caps (s, caps);
161 /* TODO: Handle channel layout somehow?
162 * Or is alaw limited to two channels? */
164 *tags = gst_tag_list_new_empty ();
166 gst_tag_list_add (*tags, GST_TAG_MERGE_APPEND, GST_TAG_AUDIO_CODEC,
167 "A-law encoded audio", NULL);
176 static const MXFEssenceElementHandler mxf_alaw_essence_element_handler = {
177 mxf_is_alaw_essence_track,
178 mxf_alaw_get_track_wrapping,
186 MXFFraction edit_rate;
190 mxf_alaw_write_func (GstBuffer * buffer, gpointer mapping_data,
191 GstAdapter * adapter, GstBuffer ** outbuf, gboolean flush)
193 ALawMappingData *md = mapping_data;
196 gst_util_uint64_scale (md->rate, md->edit_rate.d, md->edit_rate.n);
198 md->error += (md->edit_rate.d * md->rate) % (md->edit_rate.n);
199 if (md->error >= md->edit_rate.n) {
204 bytes = speu * md->channels;
207 gst_adapter_push (adapter, buffer);
209 if (gst_adapter_available (adapter) == 0)
213 bytes = MIN (gst_adapter_available (adapter), bytes);
215 if (gst_adapter_available (adapter) >= bytes) {
216 *outbuf = gst_adapter_take_buffer (adapter, bytes);
219 if (gst_adapter_available (adapter) >= bytes)
220 return GST_FLOW_CUSTOM_SUCCESS;
225 static const guint8 alaw_essence_container_ul[] = {
226 0x06, 0x0e, 0x2b, 0x34, 0x04, 0x01, 0x01, 0x03,
227 0x0d, 0x01, 0x03, 0x01, 0x02, 0x0a, 0x01, 0x00
230 static const MXFUL mxf_sound_essence_compression_alaw =
231 { {0x06, 0x0E, 0x2B, 0x34, 0x04, 0x01, 0x01, 0x03, 0x04, 0x02, 0x02, 0x02,
232 0x03, 0x01, 0x01, 0x00}
235 static MXFMetadataFileDescriptor *
236 mxf_alaw_get_descriptor (GstPadTemplate * tmpl, GstCaps * caps,
237 MXFEssenceElementWriteFunc * handler, gpointer * mapping_data)
239 MXFMetadataGenericSoundEssenceDescriptor *ret;
244 s = gst_caps_get_structure (caps, 0);
245 if (strcmp (gst_structure_get_name (s), "audio/x-alaw") != 0 ||
246 !gst_structure_get_int (s, "rate", &rate) ||
247 !gst_structure_get_int (s, "channels", &channels)) {
248 GST_ERROR ("Invalid caps %" GST_PTR_FORMAT, caps);
252 ret = (MXFMetadataGenericSoundEssenceDescriptor *)
253 g_object_new (MXF_TYPE_METADATA_GENERIC_SOUND_ESSENCE_DESCRIPTOR, NULL);
255 memcpy (&ret->parent.essence_container, &alaw_essence_container_ul, 16);
256 memcpy (&ret->sound_essence_compression, &mxf_sound_essence_compression_alaw,
259 if (!mxf_metadata_generic_sound_essence_descriptor_from_caps (ret, caps)) {
260 g_object_unref (ret);
264 *handler = mxf_alaw_write_func;
266 md = g_new0 (ALawMappingData, 1);
268 md->channels = channels;
271 return (MXFMetadataFileDescriptor *) ret;
275 mxf_alaw_update_descriptor (MXFMetadataFileDescriptor * d, GstCaps * caps,
276 gpointer mapping_data, GstBuffer * buf)
282 mxf_alaw_get_edit_rate (MXFMetadataFileDescriptor * a, GstCaps * caps,
283 gpointer mapping_data, GstBuffer * buf, MXFMetadataSourcePackage * package,
284 MXFMetadataTimelineTrack * track, MXFFraction * edit_rate)
287 gdouble min = G_MAXDOUBLE;
288 ALawMappingData *md = mapping_data;
290 for (i = 0; i < package->parent.n_tracks; i++) {
291 MXFMetadataTimelineTrack *tmp;
293 if (!MXF_IS_METADATA_TIMELINE_TRACK (package->parent.tracks[i]) ||
294 package->parent.tracks[i] == (MXFMetadataTrack *) track)
297 tmp = MXF_METADATA_TIMELINE_TRACK (package->parent.tracks[i]);
298 if (((gdouble) tmp->edit_rate.n) / ((gdouble) tmp->edit_rate.d) < min) {
299 min = ((gdouble) tmp->edit_rate.n) / ((gdouble) tmp->edit_rate.d);
300 memcpy (edit_rate, &tmp->edit_rate, sizeof (MXFFraction));
304 if (min == G_MAXDOUBLE) {
305 /* 100ms edit units */
310 memcpy (&md->edit_rate, edit_rate, sizeof (MXFFraction));
314 mxf_alaw_get_track_number_template (MXFMetadataFileDescriptor * a,
315 GstCaps * caps, gpointer mapping_data)
317 return (0x16 << 24) | (0x08 << 8);
320 static MXFEssenceElementWriter mxf_alaw_essence_element_writer = {
321 mxf_alaw_get_descriptor,
322 mxf_alaw_update_descriptor,
323 mxf_alaw_get_edit_rate,
324 mxf_alaw_get_track_number_template,
331 "rate = (int) [ 8000, 192000 ], " \
332 "channels = (int) [ 1, 2 ]"
338 mxf_essence_element_handler_register (&mxf_alaw_essence_element_handler);
340 mxf_alaw_essence_element_writer.pad_template =
341 gst_pad_template_new ("alaw_audio_sink_%u", GST_PAD_SINK, GST_PAD_REQUEST,
342 tmp = gst_caps_from_string (ALAW_CAPS));
343 gst_caps_unref (tmp);
344 memcpy (&mxf_alaw_essence_element_writer.data_definition,
345 mxf_metadata_track_identifier_get (MXF_METADATA_TRACK_SOUND_ESSENCE), 16);
346 mxf_essence_element_writer_register (&mxf_alaw_essence_element_writer);