| /* |
| * LPCM codecs for PCM formats found in MPEG streams |
| * Copyright (c) 2009 Christian Schmidt |
| * |
| * This file is part of FFmpeg. |
| * |
| * FFmpeg is free software; you can redistribute it and/or |
| * modify it under the terms of the GNU Lesser General Public |
| * License as published by the Free Software Foundation; either |
| * version 2.1 of the License, or (at your option) any later version. |
| * |
| * FFmpeg is distributed in the hope that it will be useful, |
| * but WITHOUT ANY WARRANTY; without even the implied warranty of |
| * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU |
| * Lesser General Public License for more details. |
| * |
| * You should have received a copy of the GNU Lesser General Public |
| * License along with FFmpeg; if not, write to the Free Software |
| * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA |
| */ |
| |
| /** |
| * @file |
| * PCM codecs for encodings found in MPEG streams (DVD/Blu-ray) |
| */ |
| |
| #include "libavutil/audioconvert.h" |
| #include "avcodec.h" |
| #include "bytestream.h" |
| |
| /* |
| * Channel Mapping according to |
| * Blu-ray Disc Read-Only Format Version 1 |
| * Part 3: Audio Visual Basic Specifications |
| * mono M1 X |
| * stereo L R |
| * 3/0 L R C X |
| * 2/1 L R S X |
| * 3/1 L R C S |
| * 2/2 L R LS RS |
| * 3/2 L R C LS RS X |
| * 3/2+lfe L R C LS RS lfe |
| * 3/4 L R C LS Rls Rrs RS X |
| * 3/4+lfe L R C LS Rls Rrs RS lfe |
| */ |
| |
| /** |
| * Parse the header of a LPCM frame read from a MPEG-TS stream |
| * @param avctx the codec context |
| * @param header pointer to the first four bytes of the data packet |
| */ |
| static int pcm_bluray_parse_header(AVCodecContext *avctx, |
| const uint8_t *header) |
| { |
| static const uint8_t bits_per_samples[4] = { 0, 16, 20, 24 }; |
| static const uint32_t channel_layouts[16] = { |
| 0, AV_CH_LAYOUT_MONO, 0, AV_CH_LAYOUT_STEREO, AV_CH_LAYOUT_SURROUND, |
| AV_CH_LAYOUT_2_1, AV_CH_LAYOUT_4POINT0, AV_CH_LAYOUT_2_2, AV_CH_LAYOUT_5POINT0, |
| AV_CH_LAYOUT_5POINT1, AV_CH_LAYOUT_7POINT0, AV_CH_LAYOUT_7POINT1, 0, 0, 0, 0 |
| }; |
| static const uint8_t channels[16] = { |
| 0, 1, 0, 2, 3, 3, 4, 4, 5, 6, 7, 8, 0, 0, 0, 0 |
| }; |
| uint8_t channel_layout = header[2] >> 4; |
| |
| if (avctx->debug & FF_DEBUG_PICT_INFO) |
| av_dlog(avctx, "pcm_bluray_parse_header: header = %02x%02x%02x%02x\n", |
| header[0], header[1], header[2], header[3]); |
| |
| /* get the sample depth and derive the sample format from it */ |
| avctx->bits_per_coded_sample = bits_per_samples[header[3] >> 6]; |
| if (!avctx->bits_per_coded_sample) { |
| av_log(avctx, AV_LOG_ERROR, "unsupported sample depth (0)\n"); |
| return -1; |
| } |
| avctx->sample_fmt = avctx->bits_per_coded_sample == 16 ? AV_SAMPLE_FMT_S16 : |
| AV_SAMPLE_FMT_S32; |
| |
| /* get the sample rate. Not all values are known or exist. */ |
| switch (header[2] & 0x0f) { |
| case 1: |
| avctx->sample_rate = 48000; |
| break; |
| case 4: |
| avctx->sample_rate = 96000; |
| break; |
| case 5: |
| avctx->sample_rate = 192000; |
| break; |
| default: |
| avctx->sample_rate = 0; |
| av_log(avctx, AV_LOG_ERROR, "unsupported sample rate (%d)\n", |
| header[2] & 0x0f); |
| return -1; |
| } |
| |
| /* |
| * get the channel number (and mapping). Not all values are known or exist. |
| * It must be noted that the number of channels in the MPEG stream can |
| * differ from the actual meaningful number, e.g. mono audio still has two |
| * channels, one being empty. |
| */ |
| avctx->channel_layout = channel_layouts[channel_layout]; |
| avctx->channels = channels[channel_layout]; |
| if (!avctx->channels) { |
| av_log(avctx, AV_LOG_ERROR, "unsupported channel configuration (%d)\n", |
| channel_layout); |
| return -1; |
| } |
| |
| avctx->bit_rate = avctx->channels * avctx->sample_rate * |
| avctx->bits_per_coded_sample; |
| |
| if (avctx->debug & FF_DEBUG_PICT_INFO) |
| av_dlog(avctx, |
| "pcm_bluray_parse_header: %d channels, %d bits per sample, %d kHz, %d kbit\n", |
| avctx->channels, avctx->bits_per_coded_sample, |
| avctx->sample_rate, avctx->bit_rate); |
| return 0; |
| } |
| |
| static int pcm_bluray_decode_frame(AVCodecContext *avctx, |
| void *data, |
| int *data_size, |
| AVPacket *avpkt) |
| { |
| const uint8_t *src = avpkt->data; |
| int buf_size = avpkt->size; |
| int num_source_channels, channel, retval; |
| int sample_size, samples, output_size; |
| int16_t *dst16 = data; |
| int32_t *dst32 = data; |
| |
| if (buf_size < 4) { |
| av_log(avctx, AV_LOG_ERROR, "PCM packet too small\n"); |
| return -1; |
| } |
| |
| if (pcm_bluray_parse_header(avctx, src)) |
| return -1; |
| src += 4; |
| buf_size -= 4; |
| |
| /* There's always an even number of channels in the source */ |
| num_source_channels = FFALIGN(avctx->channels, 2); |
| sample_size = (num_source_channels * avctx->bits_per_coded_sample) >> 3; |
| samples = buf_size / sample_size; |
| |
| output_size = samples * avctx->channels * |
| (avctx->sample_fmt == AV_SAMPLE_FMT_S32 ? 4 : 2); |
| if (output_size > *data_size) { |
| av_log(avctx, AV_LOG_ERROR, |
| "Insufficient output buffer space (%d bytes, needed %d bytes)\n", |
| *data_size, output_size); |
| return -1; |
| } |
| *data_size = output_size; |
| |
| if (samples) { |
| switch (avctx->channel_layout) { |
| /* cases with same number of source and coded channels */ |
| case AV_CH_LAYOUT_STEREO: |
| case AV_CH_LAYOUT_4POINT0: |
| case AV_CH_LAYOUT_2_2: |
| samples *= num_source_channels; |
| if (AV_SAMPLE_FMT_S16 == avctx->sample_fmt) { |
| #if HAVE_BIGENDIAN |
| memcpy(dst16, src, output_size); |
| #else |
| do { |
| *dst16++ = bytestream_get_be16(&src); |
| } while (--samples); |
| #endif |
| } else { |
| do { |
| *dst32++ = bytestream_get_be24(&src) << 8; |
| } while (--samples); |
| } |
| break; |
| /* cases where number of source channels = coded channels + 1 */ |
| case AV_CH_LAYOUT_MONO: |
| case AV_CH_LAYOUT_SURROUND: |
| case AV_CH_LAYOUT_2_1: |
| case AV_CH_LAYOUT_5POINT0: |
| if (AV_SAMPLE_FMT_S16 == avctx->sample_fmt) { |
| do { |
| #if HAVE_BIGENDIAN |
| memcpy(dst16, src, avctx->channels * 2); |
| dst16 += avctx->channels; |
| src += sample_size; |
| #else |
| channel = avctx->channels; |
| do { |
| *dst16++ = bytestream_get_be16(&src); |
| } while (--channel); |
| src += 2; |
| #endif |
| } while (--samples); |
| } else { |
| do { |
| channel = avctx->channels; |
| do { |
| *dst32++ = bytestream_get_be24(&src) << 8; |
| } while (--channel); |
| src += 3; |
| } while (--samples); |
| } |
| break; |
| /* remapping: L, R, C, LBack, RBack, LF */ |
| case AV_CH_LAYOUT_5POINT1: |
| if (AV_SAMPLE_FMT_S16 == avctx->sample_fmt) { |
| do { |
| dst16[0] = bytestream_get_be16(&src); |
| dst16[1] = bytestream_get_be16(&src); |
| dst16[2] = bytestream_get_be16(&src); |
| dst16[4] = bytestream_get_be16(&src); |
| dst16[5] = bytestream_get_be16(&src); |
| dst16[3] = bytestream_get_be16(&src); |
| dst16 += 6; |
| } while (--samples); |
| } else { |
| do { |
| dst32[0] = bytestream_get_be24(&src) << 8; |
| dst32[1] = bytestream_get_be24(&src) << 8; |
| dst32[2] = bytestream_get_be24(&src) << 8; |
| dst32[4] = bytestream_get_be24(&src) << 8; |
| dst32[5] = bytestream_get_be24(&src) << 8; |
| dst32[3] = bytestream_get_be24(&src) << 8; |
| dst32 += 6; |
| } while (--samples); |
| } |
| break; |
| /* remapping: L, R, C, LSide, LBack, RBack, RSide, <unused> */ |
| case AV_CH_LAYOUT_7POINT0: |
| if (AV_SAMPLE_FMT_S16 == avctx->sample_fmt) { |
| do { |
| dst16[0] = bytestream_get_be16(&src); |
| dst16[1] = bytestream_get_be16(&src); |
| dst16[2] = bytestream_get_be16(&src); |
| dst16[5] = bytestream_get_be16(&src); |
| dst16[3] = bytestream_get_be16(&src); |
| dst16[4] = bytestream_get_be16(&src); |
| dst16[6] = bytestream_get_be16(&src); |
| dst16 += 7; |
| src += 2; |
| } while (--samples); |
| } else { |
| do { |
| dst32[0] = bytestream_get_be24(&src) << 8; |
| dst32[1] = bytestream_get_be24(&src) << 8; |
| dst32[2] = bytestream_get_be24(&src) << 8; |
| dst32[5] = bytestream_get_be24(&src) << 8; |
| dst32[3] = bytestream_get_be24(&src) << 8; |
| dst32[4] = bytestream_get_be24(&src) << 8; |
| dst32[6] = bytestream_get_be24(&src) << 8; |
| dst32 += 7; |
| src += 3; |
| } while (--samples); |
| } |
| break; |
| /* remapping: L, R, C, LSide, LBack, RBack, RSide, LF */ |
| case AV_CH_LAYOUT_7POINT1: |
| if (AV_SAMPLE_FMT_S16 == avctx->sample_fmt) { |
| do { |
| dst16[0] = bytestream_get_be16(&src); |
| dst16[1] = bytestream_get_be16(&src); |
| dst16[2] = bytestream_get_be16(&src); |
| dst16[6] = bytestream_get_be16(&src); |
| dst16[4] = bytestream_get_be16(&src); |
| dst16[5] = bytestream_get_be16(&src); |
| dst16[7] = bytestream_get_be16(&src); |
| dst16[3] = bytestream_get_be16(&src); |
| dst16 += 8; |
| } while (--samples); |
| } else { |
| do { |
| dst32[0] = bytestream_get_be24(&src) << 8; |
| dst32[1] = bytestream_get_be24(&src) << 8; |
| dst32[2] = bytestream_get_be24(&src) << 8; |
| dst32[6] = bytestream_get_be24(&src) << 8; |
| dst32[4] = bytestream_get_be24(&src) << 8; |
| dst32[5] = bytestream_get_be24(&src) << 8; |
| dst32[7] = bytestream_get_be24(&src) << 8; |
| dst32[3] = bytestream_get_be24(&src) << 8; |
| dst32 += 8; |
| } while (--samples); |
| } |
| break; |
| } |
| } |
| |
| retval = src - avpkt->data; |
| if (avctx->debug & FF_DEBUG_BITSTREAM) |
| av_dlog(avctx, "pcm_bluray_decode_frame: decoded %d -> %d bytes\n", |
| retval, *data_size); |
| return retval; |
| } |
| |
| AVCodec ff_pcm_bluray_decoder = { |
| "pcm_bluray", |
| AVMEDIA_TYPE_AUDIO, |
| CODEC_ID_PCM_BLURAY, |
| 0, |
| NULL, |
| NULL, |
| NULL, |
| pcm_bluray_decode_frame, |
| .sample_fmts = (const enum AVSampleFormat[]){AV_SAMPLE_FMT_S16, AV_SAMPLE_FMT_S32, |
| AV_SAMPLE_FMT_NONE}, |
| .long_name = NULL_IF_CONFIG_SMALL("PCM signed 16|20|24-bit big-endian for Blu-ray media"), |
| }; |