1 /* GStreamer Wavpack plugin
2 * Copyright (c) 2005 Arwed v. Merkatz <v.merkatz@gmx.net>
3 * Copyright (c) 1998 - 2005 Conifer Software
4 * Copyright (c) 2006 Sebastian Dröge <slomo@circular-chaos.org>
5 *
6 * gstwavpackcommon.c: common helper functions
7 *
8 * This library is free software; you can redistribute it and/or
9 * modify it under the terms of the GNU Library General Public
10 * License as published by the Free Software Foundation; either
11 * version 2 of the License, or (at your option) any later version.
12 *
13 * This library is distributed in the hope that it will be useful,
14 * but WITHOUT ANY WARRANTY; without even the implied warranty of
15 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
16 * Library General Public License for more details.
17 *
18 * You should have received a copy of the GNU Library General Public
19 * License along with this library; if not, write to the
20 * Free Software Foundation, Inc., 51 Franklin St, Fifth Floor,
21 * Boston, MA 02110-1301, USA.
22 */
23
24 #ifdef HAVE_CONFIG_H
25 #include "config.h"
26 #endif
27
28 #include "gstwavpackcommon.h"
29 #include <string.h>
30
31 #include <gst/gst.h>
32
33 GST_DEBUG_CATEGORY_EXTERN (wavpack_debug);
34 #define GST_CAT_DEFAULT wavpack_debug
35
36 gboolean
gst_wavpack_read_header(WavpackHeader * header,guint8 * buf)37 gst_wavpack_read_header (WavpackHeader * header, guint8 * buf)
38 {
39 memmove (header, buf, sizeof (WavpackHeader));
40
41 WavpackLittleEndianToNative (header, (char *) WavpackHeaderFormat);
42
43 return (memcmp (header->ckID, "wvpk", 4) == 0);
44 }
45
46 /* inspired by the original one in wavpack */
47 gboolean
gst_wavpack_read_metadata(GstWavpackMetadata * wpmd,guint8 * header_data,guint8 ** p_data)48 gst_wavpack_read_metadata (GstWavpackMetadata * wpmd, guint8 * header_data,
49 guint8 ** p_data)
50 {
51 WavpackHeader hdr;
52 guint8 *end;
53
54 gst_wavpack_read_header (&hdr, header_data);
55 end = header_data + hdr.ckSize + 8;
56
57 if (end - *p_data < 2)
58 return FALSE;
59
60 wpmd->id = GST_READ_UINT8 (*p_data);
61 wpmd->byte_length = 2 * (guint) GST_READ_UINT8 (*p_data + 1);
62
63 *p_data += 2;
64
65 if ((wpmd->id & ID_LARGE) == ID_LARGE) {
66 guint extra;
67
68 wpmd->id &= ~ID_LARGE;
69
70 if (end - *p_data < 2)
71 return FALSE;
72
73 extra = GST_READ_UINT16_LE (*p_data);
74 wpmd->byte_length += (extra << 9);
75 *p_data += 2;
76 }
77
78 if ((wpmd->id & ID_ODD_SIZE) == ID_ODD_SIZE) {
79 wpmd->id &= ~ID_ODD_SIZE;
80 --wpmd->byte_length;
81 }
82
83 if (wpmd->byte_length > 0) {
84 if (end - *p_data < wpmd->byte_length + (wpmd->byte_length & 1)) {
85 wpmd->data = NULL;
86 return FALSE;
87 }
88
89 wpmd->data = *p_data;
90 *p_data += wpmd->byte_length + (wpmd->byte_length & 1);
91 } else {
92 wpmd->data = NULL;
93 }
94
95 return TRUE;
96 }
97
98 gint
gst_wavpack_get_default_channel_mask(gint nchannels)99 gst_wavpack_get_default_channel_mask (gint nchannels)
100 {
101 gint channel_mask = 0;
102
103 /* Set the default channel mask for the given number of channels.
104 * It's the same as for WAVE_FORMAT_EXTENDED:
105 * http://www.microsoft.com/whdc/device/audio/multichaud.mspx
106 */
107 switch (nchannels) {
108 case 11:
109 channel_mask |= 0x00400;
110 channel_mask |= 0x00200;
111 case 9:
112 channel_mask |= 0x00100;
113 case 8:
114 channel_mask |= 0x00080;
115 channel_mask |= 0x00040;
116 case 6:
117 channel_mask |= 0x00020;
118 channel_mask |= 0x00010;
119 case 4:
120 channel_mask |= 0x00008;
121 case 3:
122 channel_mask |= 0x00004;
123 case 2:
124 channel_mask |= 0x00002;
125 channel_mask |= 0x00001;
126 break;
127 case 1:
128 /* For mono use front center */
129 channel_mask |= 0x00004;
130 break;
131 }
132
133 return channel_mask;
134 }
135
136 static const struct
137 {
138 const guint32 ms_mask;
139 const GstAudioChannelPosition gst_pos;
140 } layout_mapping[] = {
141 {
142 0x00001, GST_AUDIO_CHANNEL_POSITION_FRONT_LEFT}, {
143 0x00002, GST_AUDIO_CHANNEL_POSITION_FRONT_RIGHT}, {
144 0x00004, GST_AUDIO_CHANNEL_POSITION_FRONT_CENTER}, {
145 0x00008, GST_AUDIO_CHANNEL_POSITION_LFE1}, {
146 0x00010, GST_AUDIO_CHANNEL_POSITION_REAR_LEFT}, {
147 0x00020, GST_AUDIO_CHANNEL_POSITION_REAR_RIGHT}, {
148 0x00040, GST_AUDIO_CHANNEL_POSITION_FRONT_LEFT_OF_CENTER}, {
149 0x00080, GST_AUDIO_CHANNEL_POSITION_FRONT_RIGHT_OF_CENTER}, {
150 0x00100, GST_AUDIO_CHANNEL_POSITION_REAR_CENTER}, {
151 0x00200, GST_AUDIO_CHANNEL_POSITION_SIDE_LEFT}, {
152 0x00400, GST_AUDIO_CHANNEL_POSITION_SIDE_RIGHT}, {
153 0x00800, GST_AUDIO_CHANNEL_POSITION_TOP_CENTER}, {
154 0x01000, GST_AUDIO_CHANNEL_POSITION_TOP_FRONT_LEFT}, {
155 0x02000, GST_AUDIO_CHANNEL_POSITION_TOP_FRONT_CENTER}, {
156 0x04000, GST_AUDIO_CHANNEL_POSITION_TOP_FRONT_RIGHT}, {
157 0x08000, GST_AUDIO_CHANNEL_POSITION_TOP_REAR_LEFT}, {
158 0x10000, GST_AUDIO_CHANNEL_POSITION_TOP_REAR_CENTER}, {
159 0x20000, GST_AUDIO_CHANNEL_POSITION_TOP_REAR_RIGHT}
160 };
161
162 #define MAX_CHANNEL_POSITIONS G_N_ELEMENTS (layout_mapping)
163
164 gboolean
gst_wavpack_get_channel_positions(gint num_channels,gint layout,GstAudioChannelPosition * pos)165 gst_wavpack_get_channel_positions (gint num_channels, gint layout,
166 GstAudioChannelPosition * pos)
167 {
168 gint i, p;
169
170 if (num_channels == 1 && layout == 0x00004) {
171 pos[0] = GST_AUDIO_CHANNEL_POSITION_MONO;
172 return TRUE;
173 }
174
175 p = 0;
176 for (i = 0; i < MAX_CHANNEL_POSITIONS; ++i) {
177 if ((layout & layout_mapping[i].ms_mask) != 0) {
178 if (p >= num_channels) {
179 GST_WARNING ("More bits set in the channel layout map than there "
180 "are channels! Broken file");
181 return FALSE;
182 }
183 if (layout_mapping[i].gst_pos == GST_AUDIO_CHANNEL_POSITION_INVALID) {
184 GST_WARNING ("Unsupported channel position (mask 0x%08x) in channel "
185 "layout map - ignoring those channels", layout_mapping[i].ms_mask);
186 /* what to do? just ignore it and let downstream deal with a channel
187 * layout that has INVALID positions in it for now ... */
188 }
189 pos[p] = layout_mapping[i].gst_pos;
190 ++p;
191 }
192 }
193
194 if (p != num_channels) {
195 GST_WARNING ("Only %d bits set in the channel layout map, but there are "
196 "supposed to be %d channels! Broken file", p, num_channels);
197 return FALSE;
198 }
199
200 return TRUE;
201 }
202
203 GstAudioChannelPosition *
gst_wavpack_get_default_channel_positions(gint nchannels)204 gst_wavpack_get_default_channel_positions (gint nchannels)
205 {
206 GstAudioChannelPosition *pos = g_new (GstAudioChannelPosition, nchannels);
207 gint i;
208
209 if (nchannels == 1) {
210 pos[0] = GST_AUDIO_CHANNEL_POSITION_FRONT_CENTER;
211 return pos;
212 }
213
214 for (i = 0; i < nchannels; i++)
215 pos[i] = layout_mapping[i].gst_pos;
216
217 return pos;
218 }
219
220 gint
gst_wavpack_get_channel_mask_from_positions(GstAudioChannelPosition * pos,gint nchannels)221 gst_wavpack_get_channel_mask_from_positions (GstAudioChannelPosition * pos,
222 gint nchannels)
223 {
224 gint channel_mask = 0;
225 gint i, j;
226
227 if (nchannels == 1 && pos[0] == GST_AUDIO_CHANNEL_POSITION_MONO) {
228 channel_mask = 0x00000004;
229 return channel_mask;
230 }
231
232 /* FIXME: not exactly efficient but otherwise we need an inverse
233 * mapping table too */
234 for (i = 0; i < nchannels; i++) {
235 for (j = 0; j < MAX_CHANNEL_POSITIONS; j++) {
236 if (pos[i] == layout_mapping[j].gst_pos) {
237 channel_mask |= layout_mapping[j].ms_mask;
238 break;
239 }
240 }
241 }
242
243 return channel_mask;
244 }
245
246 gboolean
gst_wavpack_set_channel_mapping(GstAudioChannelPosition * pos,gint nchannels,gint8 * channel_mapping)247 gst_wavpack_set_channel_mapping (GstAudioChannelPosition * pos, gint nchannels,
248 gint8 * channel_mapping)
249 {
250 gint i, j;
251 gboolean ret = TRUE;
252
253 for (i = 0; i < nchannels; i++) {
254 for (j = 0; j < MAX_CHANNEL_POSITIONS; j++) {
255 if (pos[i] == layout_mapping[j].gst_pos) {
256 channel_mapping[i] = j;
257 ret &= (i == j);
258 break;
259 }
260 }
261 }
262
263 return !ret;
264 }
265