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 */ 53static 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 av_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 av_dlog(avctx, 120 "pcm_bluray_parse_header: %d channels, %d bits per sample, %d Hz, %d bit/s\n", 121 avctx->channels, avctx->bits_per_coded_sample, 122 avctx->sample_rate, avctx->bit_rate); 123 return 0; 124} 125 126static 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 av_dlog(avctx, "pcm_bluray_decode_frame: decoded %d -> %d bytes\n", 300 retval, buf_size); 301 return retval + 4; 302} 303 304AVCodec 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 = CODEC_CAP_DR1, 311 .sample_fmts = (const enum AVSampleFormat[]){ 312 AV_SAMPLE_FMT_S16, AV_SAMPLE_FMT_S32, AV_SAMPLE_FMT_NONE 313 }, 314}; 315