diff options
Diffstat (limited to 'ffmpeg1/libavcodec/mlp_parser.c')
| -rw-r--r-- | ffmpeg1/libavcodec/mlp_parser.c | 398 |
1 files changed, 398 insertions, 0 deletions
diff --git a/ffmpeg1/libavcodec/mlp_parser.c b/ffmpeg1/libavcodec/mlp_parser.c new file mode 100644 index 0000000..2cc4b91 --- /dev/null +++ b/ffmpeg1/libavcodec/mlp_parser.c @@ -0,0 +1,398 @@ +/* + * MLP parser + * Copyright (c) 2007 Ian Caulfield + * + * 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 + * MLP parser + */ + +#include <stdint.h> + +#include "libavutil/channel_layout.h" +#include "libavutil/crc.h" +#include "get_bits.h" +#include "parser.h" +#include "mlp_parser.h" +#include "mlp.h" + +static const uint8_t mlp_quants[16] = { + 16, 20, 24, 0, 0, 0, 0, 0, + 0, 0, 0, 0, 0, 0, 0, 0, +}; + +static const uint8_t mlp_channels[32] = { + 1, 2, 3, 4, 3, 4, 5, 3, 4, 5, 4, 5, 6, 4, 5, 4, + 5, 6, 5, 5, 6, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, +}; + +const uint64_t ff_mlp_layout[32] = { + AV_CH_LAYOUT_MONO, + AV_CH_LAYOUT_STEREO, + AV_CH_LAYOUT_2_1, + AV_CH_LAYOUT_QUAD, + AV_CH_LAYOUT_STEREO|AV_CH_LOW_FREQUENCY, + AV_CH_LAYOUT_2_1|AV_CH_LOW_FREQUENCY, + AV_CH_LAYOUT_QUAD|AV_CH_LOW_FREQUENCY, + AV_CH_LAYOUT_SURROUND, + AV_CH_LAYOUT_4POINT0, + AV_CH_LAYOUT_5POINT0_BACK, + AV_CH_LAYOUT_SURROUND|AV_CH_LOW_FREQUENCY, + AV_CH_LAYOUT_4POINT0|AV_CH_LOW_FREQUENCY, + AV_CH_LAYOUT_5POINT1_BACK, + AV_CH_LAYOUT_4POINT0, + AV_CH_LAYOUT_5POINT0_BACK, + AV_CH_LAYOUT_SURROUND|AV_CH_LOW_FREQUENCY, + AV_CH_LAYOUT_4POINT0|AV_CH_LOW_FREQUENCY, + AV_CH_LAYOUT_5POINT1_BACK, + AV_CH_LAYOUT_QUAD|AV_CH_LOW_FREQUENCY, + AV_CH_LAYOUT_5POINT0_BACK, + AV_CH_LAYOUT_5POINT1_BACK, + 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0 +}; + +static const uint8_t thd_chancount[13] = { +// LR C LFE LRs LRvh LRc LRrs Cs Ts LRsd LRw Cvh LFE2 + 2, 1, 1, 2, 2, 2, 2, 1, 1, 2, 2, 1, 1 +}; + +static const uint64_t thd_layout[13] = { + AV_CH_FRONT_LEFT|AV_CH_FRONT_RIGHT, // LR + AV_CH_FRONT_CENTER, // C + AV_CH_LOW_FREQUENCY, // LFE + AV_CH_SIDE_LEFT|AV_CH_SIDE_RIGHT, // LRs + AV_CH_TOP_FRONT_LEFT|AV_CH_TOP_FRONT_RIGHT, // LRvh + AV_CH_FRONT_LEFT_OF_CENTER|AV_CH_FRONT_RIGHT_OF_CENTER, // LRc + AV_CH_BACK_LEFT|AV_CH_BACK_RIGHT, // LRrs + AV_CH_BACK_CENTER, // Cs + AV_CH_TOP_CENTER, // Ts + AV_CH_SURROUND_DIRECT_LEFT|AV_CH_SURROUND_DIRECT_RIGHT, // LRsd + AV_CH_WIDE_LEFT|AV_CH_WIDE_RIGHT, // LRw + AV_CH_TOP_FRONT_CENTER, // Cvh + AV_CH_LOW_FREQUENCY_2, // LFE2 +}; + +static int mlp_samplerate(int in) +{ + if (in == 0xF) + return 0; + + return (in & 8 ? 44100 : 48000) << (in & 7) ; +} + +static int truehd_channels(int chanmap) +{ + int channels = 0, i; + + for (i = 0; i < 13; i++) + channels += thd_chancount[i] * ((chanmap >> i) & 1); + + return channels; +} + +uint64_t ff_truehd_layout(int chanmap) +{ + int i; + uint64_t layout = 0; + + for (i = 0; i < 13; i++) + layout |= thd_layout[i] * ((chanmap >> i) & 1); + + return layout; +} + +/** Read a major sync info header - contains high level information about + * the stream - sample rate, channel arrangement etc. Most of this + * information is not actually necessary for decoding, only for playback. + * gb must be a freshly initialized GetBitContext with no bits read. + */ + +int ff_mlp_read_major_sync(void *log, MLPHeaderInfo *mh, GetBitContext *gb) +{ + int ratebits, channel_arrangement; + uint16_t checksum; + + av_assert1(get_bits_count(gb) == 0); + + if (gb->size_in_bits < 28 << 3) { + av_log(log, AV_LOG_ERROR, "packet too short, unable to read major sync\n"); + return -1; + } + + checksum = ff_mlp_checksum16(gb->buffer, 26); + if (checksum != AV_RL16(gb->buffer+26)) { + av_log(log, AV_LOG_ERROR, "major sync info header checksum error\n"); + return AVERROR_INVALIDDATA; + } + + if (get_bits_long(gb, 24) != 0xf8726f) /* Sync words */ + return AVERROR_INVALIDDATA; + + mh->stream_type = get_bits(gb, 8); + + if (mh->stream_type == 0xbb) { + mh->group1_bits = mlp_quants[get_bits(gb, 4)]; + mh->group2_bits = mlp_quants[get_bits(gb, 4)]; + + ratebits = get_bits(gb, 4); + mh->group1_samplerate = mlp_samplerate(ratebits); + mh->group2_samplerate = mlp_samplerate(get_bits(gb, 4)); + + skip_bits(gb, 11); + + mh->channel_arrangement= + channel_arrangement = get_bits(gb, 5); + mh->channels_mlp = mlp_channels[channel_arrangement]; + mh->channel_layout_mlp = ff_mlp_layout[channel_arrangement]; + } else if (mh->stream_type == 0xba) { + mh->group1_bits = 24; // TODO: Is this information actually conveyed anywhere? + mh->group2_bits = 0; + + ratebits = get_bits(gb, 4); + mh->group1_samplerate = mlp_samplerate(ratebits); + mh->group2_samplerate = 0; + + skip_bits(gb, 8); + + mh->channel_arrangement= + channel_arrangement = get_bits(gb, 5); + mh->channels_thd_stream1 = truehd_channels(channel_arrangement); + mh->channel_layout_thd_stream1 = ff_truehd_layout(channel_arrangement); + + skip_bits(gb, 2); + + channel_arrangement = get_bits(gb, 13); + mh->channels_thd_stream2 = truehd_channels(channel_arrangement); + mh->channel_layout_thd_stream2 = ff_truehd_layout(channel_arrangement); + } else + return AVERROR_INVALIDDATA; + + mh->access_unit_size = 40 << (ratebits & 7); + mh->access_unit_size_pow2 = 64 << (ratebits & 7); + + skip_bits_long(gb, 48); + + mh->is_vbr = get_bits1(gb); + + mh->peak_bitrate = (get_bits(gb, 15) * mh->group1_samplerate + 8) >> 4; + + mh->num_substreams = get_bits(gb, 4); + + skip_bits_long(gb, 4 + 11 * 8); + + return 0; +} + +typedef struct MLPParseContext +{ + ParseContext pc; + + int bytes_left; + + int in_sync; + + int num_substreams; +} MLPParseContext; + +static av_cold int mlp_init(AVCodecParserContext *s) +{ + ff_mlp_init_crc(); + return 0; +} + +static int mlp_parse(AVCodecParserContext *s, + AVCodecContext *avctx, + const uint8_t **poutbuf, int *poutbuf_size, + const uint8_t *buf, int buf_size) +{ + MLPParseContext *mp = s->priv_data; + int sync_present; + uint8_t parity_bits; + int next; + int i, p = 0; + + *poutbuf_size = 0; + if (buf_size == 0) + return 0; + + if (!mp->in_sync) { + // Not in sync - find a major sync header + + for (i = 0; i < buf_size; i++) { + mp->pc.state = (mp->pc.state << 8) | buf[i]; + if ((mp->pc.state & 0xfffffffe) == 0xf8726fba && + // ignore if we do not have the data for the start of header + mp->pc.index + i >= 7) { + mp->in_sync = 1; + mp->bytes_left = 0; + break; + } + } + + if (!mp->in_sync) { + if (ff_combine_frame(&mp->pc, END_NOT_FOUND, &buf, &buf_size) != -1) + av_log(avctx, AV_LOG_WARNING, "ff_combine_frame failed\n"); + return buf_size; + } + + ff_combine_frame(&mp->pc, i - 7, &buf, &buf_size); + + return i - 7; + } + + if (mp->bytes_left == 0) { + // Find length of this packet + + /* Copy overread bytes from last frame into buffer. */ + for(; mp->pc.overread>0; mp->pc.overread--) { + mp->pc.buffer[mp->pc.index++]= mp->pc.buffer[mp->pc.overread_index++]; + } + + if (mp->pc.index + buf_size < 2) { + if (ff_combine_frame(&mp->pc, END_NOT_FOUND, &buf, &buf_size) != -1) + av_log(avctx, AV_LOG_WARNING, "ff_combine_frame failed\n"); + return buf_size; + } + + mp->bytes_left = ((mp->pc.index > 0 ? mp->pc.buffer[0] : buf[0]) << 8) + | (mp->pc.index > 1 ? mp->pc.buffer[1] : buf[1-mp->pc.index]); + mp->bytes_left = (mp->bytes_left & 0xfff) * 2; + if (mp->bytes_left <= 0) { // prevent infinite loop + goto lost_sync; + } + mp->bytes_left -= mp->pc.index; + } + + next = (mp->bytes_left > buf_size) ? END_NOT_FOUND : mp->bytes_left; + + if (ff_combine_frame(&mp->pc, next, &buf, &buf_size) < 0) { + mp->bytes_left -= buf_size; + return buf_size; + } + + mp->bytes_left = 0; + + sync_present = (AV_RB32(buf + 4) & 0xfffffffe) == 0xf8726fba; + + if (!sync_present) { + /* The first nibble of a frame is a parity check of the 4-byte + * access unit header and all the 2- or 4-byte substream headers. */ + // Only check when this isn't a sync frame - syncs have a checksum. + + parity_bits = 0; + for (i = -1; i < mp->num_substreams; i++) { + parity_bits ^= buf[p++]; + parity_bits ^= buf[p++]; + + if (i < 0 || buf[p-2] & 0x80) { + parity_bits ^= buf[p++]; + parity_bits ^= buf[p++]; + } + } + + if ((((parity_bits >> 4) ^ parity_bits) & 0xF) != 0xF) { + av_log(avctx, AV_LOG_INFO, "mlpparse: Parity check failed.\n"); + goto lost_sync; + } + } else { + GetBitContext gb; + MLPHeaderInfo mh; + + init_get_bits(&gb, buf + 4, (buf_size - 4) << 3); + if (ff_mlp_read_major_sync(avctx, &mh, &gb) < 0) + goto lost_sync; + + avctx->bits_per_raw_sample = mh.group1_bits; + if (avctx->bits_per_raw_sample > 16) + avctx->sample_fmt = AV_SAMPLE_FMT_S32; + else + avctx->sample_fmt = AV_SAMPLE_FMT_S16; + avctx->sample_rate = mh.group1_samplerate; + s->duration = mh.access_unit_size; + + if(!avctx->channels || !avctx->channel_layout) { + if (mh.stream_type == 0xbb) { + /* MLP stream */ +#if FF_API_REQUEST_CHANNELS + if (avctx->request_channels > 0 && avctx->request_channels <= 2 && + mh.num_substreams > 1) { + avctx->channels = 2; + avctx->channel_layout = AV_CH_LAYOUT_STEREO; + } else +#endif + if (avctx->request_channel_layout == AV_CH_LAYOUT_STEREO && + mh.num_substreams > 1) { + avctx->channels = 2; + avctx->channel_layout = AV_CH_LAYOUT_STEREO; + } else { + avctx->channels = mh.channels_mlp; + avctx->channel_layout = mh.channel_layout_mlp; + } + } else { /* mh.stream_type == 0xba */ + /* TrueHD stream */ +#if FF_API_REQUEST_CHANNELS + if (avctx->request_channels > 0 && avctx->request_channels <= 2 && + mh.num_substreams > 1) { + avctx->channels = 2; + avctx->channel_layout = AV_CH_LAYOUT_STEREO; + } else if (avctx->request_channels > 0 && + avctx->request_channels <= mh.channels_thd_stream1) { + avctx->channels = mh.channels_thd_stream1; + avctx->channel_layout = mh.channel_layout_thd_stream1; + } else +#endif + if (avctx->request_channel_layout == AV_CH_LAYOUT_STEREO && + mh.num_substreams > 1) { + avctx->channels = 2; + avctx->channel_layout = AV_CH_LAYOUT_STEREO; + } else if (avctx->request_channel_layout == mh.channel_layout_thd_stream1 || + !mh.channels_thd_stream2) { + avctx->channels = mh.channels_thd_stream1; + avctx->channel_layout = mh.channel_layout_thd_stream1; + } else { + avctx->channels = mh.channels_thd_stream2; + avctx->channel_layout = mh.channel_layout_thd_stream2; + } + } + } + + if (!mh.is_vbr) /* Stream is CBR */ + avctx->bit_rate = mh.peak_bitrate; + + mp->num_substreams = mh.num_substreams; + } + + *poutbuf = buf; + *poutbuf_size = buf_size; + + return next; + +lost_sync: + mp->in_sync = 0; + return 1; +} + +AVCodecParser ff_mlp_parser = { + .codec_ids = { AV_CODEC_ID_MLP, AV_CODEC_ID_TRUEHD }, + .priv_data_size = sizeof(MLPParseContext), + .parser_init = mlp_init, + .parser_parse = mlp_parse, + .parser_close = ff_parse_close, +}; |