1 /*
2 * LPCM codecs for PCM format found in Blu-ray PCM streams
3 * Copyright (c) 2009, 2013 Christian Schmidt
4 *
5 * This file is part of FFmpeg.
6 *
7 * FFmpeg is free software; you can redistribute it and/or
8 * modify it under the terms of the GNU Lesser General Public
9 * License as published by the Free Software Foundation; either
10 * version 2.1 of the License, or (at your option) any later version.
11 *
12 * FFmpeg is distributed in the hope that it will be useful,
13 * but WITHOUT ANY WARRANTY; without even the implied warranty of
14 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
15 * Lesser General Public License for more details.
16 *
17 * You should have received a copy of the GNU Lesser General Public
18 * License along with FFmpeg; if not, write to the Free Software
19 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
20 */
21
22 /**
23 * @file
24 * PCM codec for Blu-ray PCM audio tracks
25 */
26
27 #include "libavutil/channel_layout.h"
28 #include "avcodec.h"
29 #include "bytestream.h"
30 #include "internal.h"
31
32 /*
33 * Channel Mapping according to
34 * Blu-ray Disc Read-Only Format Version 1
35 * Part 3: Audio Visual Basic Specifications
36 * mono M1 X
37 * stereo L R
38 * 3/0 L R C X
39 * 2/1 L R S X
40 * 3/1 L R C S
41 * 2/2 L R LS RS
42 * 3/2 L R C LS RS X
43 * 3/2+lfe L R C LS RS lfe
44 * 3/4 L R C LS Rls Rrs RS X
45 * 3/4+lfe L R C LS Rls Rrs RS lfe
46 */
47
48 /**
49 * Parse the header of a LPCM frame read from a Blu-ray MPEG-TS stream
50 * @param avctx the codec context
51 * @param header pointer to the first four bytes of the data packet
52 */
pcm_bluray_parse_header(AVCodecContext * avctx,const uint8_t * header)53 static int pcm_bluray_parse_header(AVCodecContext *avctx,
54 const uint8_t *header)
55 {
56 static const uint8_t bits_per_samples[4] = { 0, 16, 20, 24 };
57 static const uint32_t channel_layouts[16] = {
58 0, AV_CH_LAYOUT_MONO, 0, AV_CH_LAYOUT_STEREO, AV_CH_LAYOUT_SURROUND,
59 AV_CH_LAYOUT_2_1, AV_CH_LAYOUT_4POINT0, AV_CH_LAYOUT_2_2,
60 AV_CH_LAYOUT_5POINT0, AV_CH_LAYOUT_5POINT1, AV_CH_LAYOUT_7POINT0,
61 AV_CH_LAYOUT_7POINT1, 0, 0, 0, 0
62 };
63 static const uint8_t channels[16] = {
64 0, 1, 0, 2, 3, 3, 4, 4, 5, 6, 7, 8, 0, 0, 0, 0
65 };
66 uint8_t channel_layout = header[2] >> 4;
67
68 if (avctx->debug & FF_DEBUG_PICT_INFO)
69 ff_dlog(avctx, "pcm_bluray_parse_header: header = %02x%02x%02x%02x\n",
70 header[0], header[1], header[2], header[3]);
71
72 /* get the sample depth and derive the sample format from it */
73 avctx->bits_per_coded_sample = bits_per_samples[header[3] >> 6];
74 if (!(avctx->bits_per_coded_sample == 16 || avctx->bits_per_coded_sample == 24)) {
75 av_log(avctx, AV_LOG_ERROR, "unsupported sample depth (%d)\n", avctx->bits_per_coded_sample);
76 return AVERROR_INVALIDDATA;
77 }
78 avctx->sample_fmt = avctx->bits_per_coded_sample == 16 ? AV_SAMPLE_FMT_S16
79 : AV_SAMPLE_FMT_S32;
80 if (avctx->sample_fmt == AV_SAMPLE_FMT_S32)
81 avctx->bits_per_raw_sample = avctx->bits_per_coded_sample;
82
83 /* get the sample rate. Not all values are used. */
84 switch (header[2] & 0x0f) {
85 case 1:
86 avctx->sample_rate = 48000;
87 break;
88 case 4:
89 avctx->sample_rate = 96000;
90 break;
91 case 5:
92 avctx->sample_rate = 192000;
93 break;
94 default:
95 avctx->sample_rate = 0;
96 av_log(avctx, AV_LOG_ERROR, "reserved sample rate (%d)\n",
97 header[2] & 0x0f);
98 return AVERROR_INVALIDDATA;
99 }
100
101 /*
102 * get the channel number (and mapping). Not all values are used.
103 * It must be noted that the number of channels in the MPEG stream can
104 * differ from the actual meaningful number, e.g. mono audio still has two
105 * channels, one being empty.
106 */
107 avctx->channel_layout = channel_layouts[channel_layout];
108 avctx->channels = channels[channel_layout];
109 if (!avctx->channels) {
110 av_log(avctx, AV_LOG_ERROR, "reserved channel configuration (%d)\n",
111 channel_layout);
112 return AVERROR_INVALIDDATA;
113 }
114
115 avctx->bit_rate = FFALIGN(avctx->channels, 2) * avctx->sample_rate *
116 avctx->bits_per_coded_sample;
117
118 if (avctx->debug & FF_DEBUG_PICT_INFO)
119 ff_dlog(avctx,
120 "pcm_bluray_parse_header: %d channels, %d bits per sample, %d Hz, %"PRId64" bit/s\n",
121 avctx->channels, avctx->bits_per_coded_sample,
122 avctx->sample_rate, avctx->bit_rate);
123 return 0;
124 }
125
pcm_bluray_decode_frame(AVCodecContext * avctx,void * data,int * got_frame_ptr,AVPacket * avpkt)126 static int pcm_bluray_decode_frame(AVCodecContext *avctx, void *data,
127 int *got_frame_ptr, AVPacket *avpkt)
128 {
129 AVFrame *frame = data;
130 const uint8_t *src = avpkt->data;
131 int buf_size = avpkt->size;
132 GetByteContext gb;
133 int num_source_channels, channel, retval;
134 int sample_size, samples;
135 int16_t *dst16;
136 int32_t *dst32;
137
138 if (buf_size < 4) {
139 av_log(avctx, AV_LOG_ERROR, "PCM packet too small\n");
140 return AVERROR_INVALIDDATA;
141 }
142
143 if ((retval = pcm_bluray_parse_header(avctx, src)))
144 return retval;
145 src += 4;
146 buf_size -= 4;
147
148 bytestream2_init(&gb, src, buf_size);
149
150 /* There's always an even number of channels in the source */
151 num_source_channels = FFALIGN(avctx->channels, 2);
152 sample_size = (num_source_channels *
153 (avctx->sample_fmt == AV_SAMPLE_FMT_S16 ? 16 : 24)) >> 3;
154 samples = buf_size / sample_size;
155
156 /* get output buffer */
157 frame->nb_samples = samples;
158 if ((retval = ff_get_buffer(avctx, frame, 0)) < 0)
159 return retval;
160 dst16 = (int16_t *)frame->data[0];
161 dst32 = (int32_t *)frame->data[0];
162
163 if (samples) {
164 switch (avctx->channel_layout) {
165 /* cases with same number of source and coded channels */
166 case AV_CH_LAYOUT_STEREO:
167 case AV_CH_LAYOUT_4POINT0:
168 case AV_CH_LAYOUT_2_2:
169 samples *= num_source_channels;
170 if (AV_SAMPLE_FMT_S16 == avctx->sample_fmt) {
171 #if HAVE_BIGENDIAN
172 bytestream2_get_buffer(&gb, dst16, buf_size);
173 #else
174 do {
175 *dst16++ = bytestream2_get_be16u(&gb);
176 } while (--samples);
177 #endif
178 } else {
179 do {
180 *dst32++ = bytestream2_get_be24u(&gb) << 8;
181 } while (--samples);
182 }
183 break;
184 /* cases where number of source channels = coded channels + 1 */
185 case AV_CH_LAYOUT_MONO:
186 case AV_CH_LAYOUT_SURROUND:
187 case AV_CH_LAYOUT_2_1:
188 case AV_CH_LAYOUT_5POINT0:
189 if (AV_SAMPLE_FMT_S16 == avctx->sample_fmt) {
190 do {
191 #if HAVE_BIGENDIAN
192 bytestream2_get_buffer(&gb, dst16, avctx->channels * 2);
193 dst16 += avctx->channels;
194 #else
195 channel = avctx->channels;
196 do {
197 *dst16++ = bytestream2_get_be16u(&gb);
198 } while (--channel);
199 #endif
200 bytestream2_skip(&gb, 2);
201 } while (--samples);
202 } else {
203 do {
204 channel = avctx->channels;
205 do {
206 *dst32++ = bytestream2_get_be24u(&gb) << 8;
207 } while (--channel);
208 bytestream2_skip(&gb, 3);
209 } while (--samples);
210 }
211 break;
212 /* remapping: L, R, C, LBack, RBack, LF */
213 case AV_CH_LAYOUT_5POINT1:
214 if (AV_SAMPLE_FMT_S16 == avctx->sample_fmt) {
215 do {
216 dst16[0] = bytestream2_get_be16u(&gb);
217 dst16[1] = bytestream2_get_be16u(&gb);
218 dst16[2] = bytestream2_get_be16u(&gb);
219 dst16[4] = bytestream2_get_be16u(&gb);
220 dst16[5] = bytestream2_get_be16u(&gb);
221 dst16[3] = bytestream2_get_be16u(&gb);
222 dst16 += 6;
223 } while (--samples);
224 } else {
225 do {
226 dst32[0] = bytestream2_get_be24u(&gb) << 8;
227 dst32[1] = bytestream2_get_be24u(&gb) << 8;
228 dst32[2] = bytestream2_get_be24u(&gb) << 8;
229 dst32[4] = bytestream2_get_be24u(&gb) << 8;
230 dst32[5] = bytestream2_get_be24u(&gb) << 8;
231 dst32[3] = bytestream2_get_be24u(&gb) << 8;
232 dst32 += 6;
233 } while (--samples);
234 }
235 break;
236 /* remapping: L, R, C, LSide, LBack, RBack, RSide, <unused> */
237 case AV_CH_LAYOUT_7POINT0:
238 if (AV_SAMPLE_FMT_S16 == avctx->sample_fmt) {
239 do {
240 dst16[0] = bytestream2_get_be16u(&gb);
241 dst16[1] = bytestream2_get_be16u(&gb);
242 dst16[2] = bytestream2_get_be16u(&gb);
243 dst16[5] = bytestream2_get_be16u(&gb);
244 dst16[3] = bytestream2_get_be16u(&gb);
245 dst16[4] = bytestream2_get_be16u(&gb);
246 dst16[6] = bytestream2_get_be16u(&gb);
247 dst16 += 7;
248 bytestream2_skip(&gb, 2);
249 } while (--samples);
250 } else {
251 do {
252 dst32[0] = bytestream2_get_be24u(&gb) << 8;
253 dst32[1] = bytestream2_get_be24u(&gb) << 8;
254 dst32[2] = bytestream2_get_be24u(&gb) << 8;
255 dst32[5] = bytestream2_get_be24u(&gb) << 8;
256 dst32[3] = bytestream2_get_be24u(&gb) << 8;
257 dst32[4] = bytestream2_get_be24u(&gb) << 8;
258 dst32[6] = bytestream2_get_be24u(&gb) << 8;
259 dst32 += 7;
260 bytestream2_skip(&gb, 3);
261 } while (--samples);
262 }
263 break;
264 /* remapping: L, R, C, LSide, LBack, RBack, RSide, LF */
265 case AV_CH_LAYOUT_7POINT1:
266 if (AV_SAMPLE_FMT_S16 == avctx->sample_fmt) {
267 do {
268 dst16[0] = bytestream2_get_be16u(&gb);
269 dst16[1] = bytestream2_get_be16u(&gb);
270 dst16[2] = bytestream2_get_be16u(&gb);
271 dst16[6] = bytestream2_get_be16u(&gb);
272 dst16[4] = bytestream2_get_be16u(&gb);
273 dst16[5] = bytestream2_get_be16u(&gb);
274 dst16[7] = bytestream2_get_be16u(&gb);
275 dst16[3] = bytestream2_get_be16u(&gb);
276 dst16 += 8;
277 } while (--samples);
278 } else {
279 do {
280 dst32[0] = bytestream2_get_be24u(&gb) << 8;
281 dst32[1] = bytestream2_get_be24u(&gb) << 8;
282 dst32[2] = bytestream2_get_be24u(&gb) << 8;
283 dst32[6] = bytestream2_get_be24u(&gb) << 8;
284 dst32[4] = bytestream2_get_be24u(&gb) << 8;
285 dst32[5] = bytestream2_get_be24u(&gb) << 8;
286 dst32[7] = bytestream2_get_be24u(&gb) << 8;
287 dst32[3] = bytestream2_get_be24u(&gb) << 8;
288 dst32 += 8;
289 } while (--samples);
290 }
291 break;
292 }
293 }
294
295 *got_frame_ptr = 1;
296
297 retval = bytestream2_tell(&gb);
298 if (avctx->debug & FF_DEBUG_BITSTREAM)
299 ff_dlog(avctx, "pcm_bluray_decode_frame: decoded %d -> %d bytes\n",
300 retval, buf_size);
301 return retval + 4;
302 }
303
304 AVCodec ff_pcm_bluray_decoder = {
305 .name = "pcm_bluray",
306 .long_name = NULL_IF_CONFIG_SMALL("PCM signed 16|20|24-bit big-endian for Blu-ray media"),
307 .type = AVMEDIA_TYPE_AUDIO,
308 .id = AV_CODEC_ID_PCM_BLURAY,
309 .decode = pcm_bluray_decode_frame,
310 .capabilities = AV_CODEC_CAP_DR1 | AV_CODEC_CAP_CHANNEL_CONF,
311 .sample_fmts = (const enum AVSampleFormat[]){
312 AV_SAMPLE_FMT_S16, AV_SAMPLE_FMT_S32, AV_SAMPLE_FMT_NONE
313 },
314 };
315