| /* |
| * TTA (The Lossless True Audio) decoder |
| * Copyright (c) 2006 Alex Beregszaszi |
| * |
| * 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 |
| * TTA (The Lossless True Audio) decoder |
| * @see http://www.true-audio.com/ |
| * @see http://tta.corecodec.org/ |
| * @author Alex Beregszaszi |
| */ |
| |
| #define BITSTREAM_READER_LE |
| //#define DEBUG |
| #include <limits.h> |
| #include "avcodec.h" |
| #include "get_bits.h" |
| #include "internal.h" |
| #include "libavutil/crc.h" |
| |
| #define FORMAT_SIMPLE 1 |
| #define FORMAT_ENCRYPTED 2 |
| |
| #define MAX_ORDER 16 |
| typedef struct TTAFilter { |
| int32_t shift, round, error; |
| int32_t qm[MAX_ORDER]; |
| int32_t dx[MAX_ORDER]; |
| int32_t dl[MAX_ORDER]; |
| } TTAFilter; |
| |
| typedef struct TTARice { |
| uint32_t k0, k1, sum0, sum1; |
| } TTARice; |
| |
| typedef struct TTAChannel { |
| int32_t predictor; |
| TTAFilter filter; |
| TTARice rice; |
| } TTAChannel; |
| |
| typedef struct TTAContext { |
| AVCodecContext *avctx; |
| AVFrame frame; |
| GetBitContext gb; |
| const AVCRC *crc_table; |
| |
| int format, channels, bps; |
| unsigned data_length; |
| int frame_length, last_frame_length; |
| |
| int32_t *decode_buffer; |
| |
| TTAChannel *ch_ctx; |
| } TTAContext; |
| |
| static const uint32_t shift_1[] = { |
| 0x00000001, 0x00000002, 0x00000004, 0x00000008, |
| 0x00000010, 0x00000020, 0x00000040, 0x00000080, |
| 0x00000100, 0x00000200, 0x00000400, 0x00000800, |
| 0x00001000, 0x00002000, 0x00004000, 0x00008000, |
| 0x00010000, 0x00020000, 0x00040000, 0x00080000, |
| 0x00100000, 0x00200000, 0x00400000, 0x00800000, |
| 0x01000000, 0x02000000, 0x04000000, 0x08000000, |
| 0x10000000, 0x20000000, 0x40000000, 0x80000000, |
| 0x80000000, 0x80000000, 0x80000000, 0x80000000, |
| 0x80000000, 0x80000000, 0x80000000, 0x80000000 |
| }; |
| |
| static const uint32_t * const shift_16 = shift_1 + 4; |
| |
| static const int32_t ttafilter_configs[4] = { |
| 10, |
| 9, |
| 10, |
| 12 |
| }; |
| |
| static void ttafilter_init(TTAFilter *c, int32_t shift) { |
| memset(c, 0, sizeof(TTAFilter)); |
| c->shift = shift; |
| c->round = shift_1[shift-1]; |
| // c->round = 1 << (shift - 1); |
| } |
| |
| static inline void ttafilter_process(TTAFilter *c, int32_t *in) |
| { |
| register int32_t *dl = c->dl, *qm = c->qm, *dx = c->dx, sum = c->round; |
| |
| if (c->error < 0) { |
| qm[0] -= dx[0]; qm[1] -= dx[1]; qm[2] -= dx[2]; qm[3] -= dx[3]; |
| qm[4] -= dx[4]; qm[5] -= dx[5]; qm[6] -= dx[6]; qm[7] -= dx[7]; |
| } else if (c->error > 0) { |
| qm[0] += dx[0]; qm[1] += dx[1]; qm[2] += dx[2]; qm[3] += dx[3]; |
| qm[4] += dx[4]; qm[5] += dx[5]; qm[6] += dx[6]; qm[7] += dx[7]; |
| } |
| |
| sum += dl[0] * qm[0] + dl[1] * qm[1] + dl[2] * qm[2] + dl[3] * qm[3] + |
| dl[4] * qm[4] + dl[5] * qm[5] + dl[6] * qm[6] + dl[7] * qm[7]; |
| |
| dx[0] = dx[1]; dx[1] = dx[2]; dx[2] = dx[3]; dx[3] = dx[4]; |
| dl[0] = dl[1]; dl[1] = dl[2]; dl[2] = dl[3]; dl[3] = dl[4]; |
| |
| dx[4] = ((dl[4] >> 30) | 1); |
| dx[5] = ((dl[5] >> 30) | 2) & ~1; |
| dx[6] = ((dl[6] >> 30) | 2) & ~1; |
| dx[7] = ((dl[7] >> 30) | 4) & ~3; |
| |
| c->error = *in; |
| *in += (sum >> c->shift); |
| |
| dl[4] = -dl[5]; dl[5] = -dl[6]; |
| dl[6] = *in - dl[7]; dl[7] = *in; |
| dl[5] += dl[6]; dl[4] += dl[5]; |
| } |
| |
| static void rice_init(TTARice *c, uint32_t k0, uint32_t k1) |
| { |
| c->k0 = k0; |
| c->k1 = k1; |
| c->sum0 = shift_16[k0]; |
| c->sum1 = shift_16[k1]; |
| } |
| |
| static int tta_get_unary(GetBitContext *gb) |
| { |
| int ret = 0; |
| |
| // count ones |
| while (get_bits_left(gb) > 0 && get_bits1(gb)) |
| ret++; |
| return ret; |
| } |
| |
| static const int64_t tta_channel_layouts[7] = { |
| AV_CH_LAYOUT_STEREO, |
| AV_CH_LAYOUT_STEREO|AV_CH_LOW_FREQUENCY, |
| AV_CH_LAYOUT_QUAD, |
| 0, |
| AV_CH_LAYOUT_5POINT1_BACK, |
| AV_CH_LAYOUT_5POINT1_BACK|AV_CH_BACK_CENTER, |
| AV_CH_LAYOUT_7POINT1_WIDE |
| }; |
| |
| static int tta_check_crc(TTAContext *s, const uint8_t *buf, int buf_size) |
| { |
| uint32_t crc, CRC; |
| |
| CRC = AV_RL32(buf + buf_size); |
| crc = av_crc(s->crc_table, 0xFFFFFFFFU, buf, buf_size); |
| if (CRC != (crc ^ 0xFFFFFFFFU)) { |
| av_log(s->avctx, AV_LOG_ERROR, "CRC error\n"); |
| return AVERROR_INVALIDDATA; |
| } |
| |
| return 0; |
| } |
| |
| static av_cold int tta_decode_init(AVCodecContext * avctx) |
| { |
| TTAContext *s = avctx->priv_data; |
| int total_frames; |
| |
| s->avctx = avctx; |
| |
| // 30bytes includes a seektable with one frame |
| if (avctx->extradata_size < 30) |
| return AVERROR_INVALIDDATA; |
| |
| init_get_bits(&s->gb, avctx->extradata, avctx->extradata_size * 8); |
| if (show_bits_long(&s->gb, 32) == AV_RL32("TTA1")) |
| { |
| if (avctx->err_recognition & AV_EF_CRCCHECK) { |
| s->crc_table = av_crc_get_table(AV_CRC_32_IEEE_LE); |
| tta_check_crc(s, avctx->extradata, 18); |
| } |
| |
| /* signature */ |
| skip_bits_long(&s->gb, 32); |
| |
| s->format = get_bits(&s->gb, 16); |
| if (s->format > 2) { |
| av_log(s->avctx, AV_LOG_ERROR, "Invalid format\n"); |
| return AVERROR_INVALIDDATA; |
| } |
| if (s->format == FORMAT_ENCRYPTED) { |
| av_log_missing_feature(s->avctx, "Encrypted TTA", 0); |
| return AVERROR_PATCHWELCOME; |
| } |
| avctx->channels = s->channels = get_bits(&s->gb, 16); |
| if (s->channels > 1 && s->channels < 9) |
| avctx->channel_layout = tta_channel_layouts[s->channels-2]; |
| avctx->bits_per_raw_sample = get_bits(&s->gb, 16); |
| s->bps = (avctx->bits_per_raw_sample + 7) / 8; |
| avctx->sample_rate = get_bits_long(&s->gb, 32); |
| s->data_length = get_bits_long(&s->gb, 32); |
| skip_bits_long(&s->gb, 32); // CRC32 of header |
| |
| if (s->channels == 0) { |
| av_log(s->avctx, AV_LOG_ERROR, "Invalid number of channels\n"); |
| return AVERROR_INVALIDDATA; |
| } else if (avctx->sample_rate == 0) { |
| av_log(s->avctx, AV_LOG_ERROR, "Invalid samplerate\n"); |
| return AVERROR_INVALIDDATA; |
| } |
| |
| switch(s->bps) { |
| case 1: avctx->sample_fmt = AV_SAMPLE_FMT_U8; break; |
| case 2: |
| avctx->sample_fmt = AV_SAMPLE_FMT_S16; |
| break; |
| case 3: |
| avctx->sample_fmt = AV_SAMPLE_FMT_S32; |
| break; |
| //case 4: avctx->sample_fmt = AV_SAMPLE_FMT_S32; break; |
| default: |
| av_log(avctx, AV_LOG_ERROR, "Invalid/unsupported sample format.\n"); |
| return AVERROR_INVALIDDATA; |
| } |
| |
| // prevent overflow |
| if (avctx->sample_rate > 0x7FFFFFu) { |
| av_log(avctx, AV_LOG_ERROR, "sample_rate too large\n"); |
| return AVERROR(EINVAL); |
| } |
| s->frame_length = 256 * avctx->sample_rate / 245; |
| |
| s->last_frame_length = s->data_length % s->frame_length; |
| total_frames = s->data_length / s->frame_length + |
| (s->last_frame_length ? 1 : 0); |
| |
| av_log(s->avctx, AV_LOG_DEBUG, "format: %d chans: %d bps: %d rate: %d block: %d\n", |
| s->format, avctx->channels, avctx->bits_per_coded_sample, avctx->sample_rate, |
| avctx->block_align); |
| av_log(s->avctx, AV_LOG_DEBUG, "data_length: %d frame_length: %d last: %d total: %d\n", |
| s->data_length, s->frame_length, s->last_frame_length, total_frames); |
| |
| // FIXME: seek table |
| if (avctx->extradata_size <= 26 || total_frames > INT_MAX / 4 || |
| avctx->extradata_size - 26 < total_frames * 4) |
| av_log(avctx, AV_LOG_WARNING, "Seek table missing or too small\n"); |
| else if (avctx->err_recognition & AV_EF_CRCCHECK) { |
| if (tta_check_crc(s, avctx->extradata + 22, total_frames * 4)) |
| return AVERROR_INVALIDDATA; |
| } |
| skip_bits_long(&s->gb, 32 * total_frames); |
| skip_bits_long(&s->gb, 32); // CRC32 of seektable |
| |
| if(s->frame_length >= UINT_MAX / (s->channels * sizeof(int32_t))){ |
| av_log(avctx, AV_LOG_ERROR, "frame_length too large\n"); |
| return AVERROR_INVALIDDATA; |
| } |
| |
| if (s->bps < 3) { |
| s->decode_buffer = av_mallocz(sizeof(int32_t)*s->frame_length*s->channels); |
| if (!s->decode_buffer) |
| return AVERROR(ENOMEM); |
| } else |
| s->decode_buffer = NULL; |
| s->ch_ctx = av_malloc(avctx->channels * sizeof(*s->ch_ctx)); |
| if (!s->ch_ctx) { |
| av_freep(&s->decode_buffer); |
| return AVERROR(ENOMEM); |
| } |
| } else { |
| av_log(avctx, AV_LOG_ERROR, "Wrong extradata present\n"); |
| return AVERROR_INVALIDDATA; |
| } |
| |
| avcodec_get_frame_defaults(&s->frame); |
| avctx->coded_frame = &s->frame; |
| |
| return 0; |
| } |
| |
| static int tta_decode_frame(AVCodecContext *avctx, void *data, |
| int *got_frame_ptr, AVPacket *avpkt) |
| { |
| const uint8_t *buf = avpkt->data; |
| int buf_size = avpkt->size; |
| TTAContext *s = avctx->priv_data; |
| int i, ret; |
| int cur_chan = 0, framelen = s->frame_length; |
| int32_t *p; |
| |
| if (avctx->err_recognition & AV_EF_CRCCHECK) { |
| if (buf_size < 4 || tta_check_crc(s, buf, buf_size - 4)) |
| return AVERROR_INVALIDDATA; |
| } |
| |
| init_get_bits(&s->gb, buf, buf_size*8); |
| |
| /* get output buffer */ |
| s->frame.nb_samples = framelen; |
| if ((ret = ff_get_buffer(avctx, &s->frame)) < 0) { |
| av_log(avctx, AV_LOG_ERROR, "get_buffer() failed\n"); |
| return ret; |
| } |
| |
| // decode directly to output buffer for 24-bit sample format |
| if (s->bps == 3) |
| s->decode_buffer = (int32_t *)s->frame.data[0]; |
| |
| // init per channel states |
| for (i = 0; i < s->channels; i++) { |
| s->ch_ctx[i].predictor = 0; |
| ttafilter_init(&s->ch_ctx[i].filter, ttafilter_configs[s->bps-1]); |
| rice_init(&s->ch_ctx[i].rice, 10, 10); |
| } |
| |
| i = 0; |
| for (p = s->decode_buffer; p < s->decode_buffer + (framelen * s->channels); p++) { |
| int32_t *predictor = &s->ch_ctx[cur_chan].predictor; |
| TTAFilter *filter = &s->ch_ctx[cur_chan].filter; |
| TTARice *rice = &s->ch_ctx[cur_chan].rice; |
| uint32_t unary, depth, k; |
| int32_t value; |
| |
| unary = tta_get_unary(&s->gb); |
| |
| if (unary == 0) { |
| depth = 0; |
| k = rice->k0; |
| } else { |
| depth = 1; |
| k = rice->k1; |
| unary--; |
| } |
| |
| if (get_bits_left(&s->gb) < k) { |
| ret = AVERROR_INVALIDDATA; |
| goto error; |
| } |
| |
| if (k) { |
| if (k > MIN_CACHE_BITS) { |
| ret = AVERROR_INVALIDDATA; |
| goto error; |
| } |
| value = (unary << k) + get_bits(&s->gb, k); |
| } else |
| value = unary; |
| |
| // FIXME: copy paste from original |
| switch (depth) { |
| case 1: |
| rice->sum1 += value - (rice->sum1 >> 4); |
| if (rice->k1 > 0 && rice->sum1 < shift_16[rice->k1]) |
| rice->k1--; |
| else if(rice->sum1 > shift_16[rice->k1 + 1]) |
| rice->k1++; |
| value += shift_1[rice->k0]; |
| default: |
| rice->sum0 += value - (rice->sum0 >> 4); |
| if (rice->k0 > 0 && rice->sum0 < shift_16[rice->k0]) |
| rice->k0--; |
| else if(rice->sum0 > shift_16[rice->k0 + 1]) |
| rice->k0++; |
| } |
| |
| // extract coded value |
| *p = 1 + ((value >> 1) ^ ((value & 1) - 1)); |
| |
| // run hybrid filter |
| ttafilter_process(filter, p); |
| |
| // fixed order prediction |
| #define PRED(x, k) (int32_t)((((uint64_t)x << k) - x) >> k) |
| switch (s->bps) { |
| case 1: *p += PRED(*predictor, 4); break; |
| case 2: |
| case 3: *p += PRED(*predictor, 5); break; |
| case 4: *p += *predictor; break; |
| } |
| *predictor = *p; |
| |
| // flip channels |
| if (cur_chan < (s->channels-1)) |
| cur_chan++; |
| else { |
| // decorrelate in case of multiple channels |
| if (s->channels > 1) { |
| int32_t *r = p - 1; |
| for (*p += *r / 2; r > p - s->channels; r--) |
| *r = *(r + 1) - *r; |
| } |
| cur_chan = 0; |
| i++; |
| // check for last frame |
| if (i == s->last_frame_length && get_bits_left(&s->gb) / 8 == 4) { |
| s->frame.nb_samples = framelen = s->last_frame_length; |
| break; |
| } |
| } |
| } |
| |
| align_get_bits(&s->gb); |
| if (get_bits_left(&s->gb) < 32) { |
| ret = AVERROR_INVALIDDATA; |
| goto error; |
| } |
| skip_bits_long(&s->gb, 32); // frame crc |
| |
| // convert to output buffer |
| switch (s->bps) { |
| case 1: { |
| uint8_t *samples = (uint8_t *)s->frame.data[0]; |
| for (p = s->decode_buffer; p < s->decode_buffer + (framelen * s->channels); p++) |
| *samples++ = *p + 0x80; |
| break; |
| } |
| case 2: { |
| int16_t *samples = (int16_t *)s->frame.data[0]; |
| for (p = s->decode_buffer; p < s->decode_buffer + (framelen * s->channels); p++) |
| *samples++ = *p; |
| break; |
| } |
| case 3: { |
| // shift samples for 24-bit sample format |
| int32_t *samples = (int32_t *)s->frame.data[0]; |
| for (p = s->decode_buffer; p < s->decode_buffer + (framelen * s->channels); p++) |
| *samples++ <<= 8; |
| // reset decode buffer |
| s->decode_buffer = NULL; |
| break; |
| } |
| } |
| |
| *got_frame_ptr = 1; |
| *(AVFrame *)data = s->frame; |
| |
| return buf_size; |
| error: |
| // reset decode buffer |
| if (s->bps == 3) |
| s->decode_buffer = NULL; |
| return ret; |
| } |
| |
| static av_cold int tta_decode_close(AVCodecContext *avctx) { |
| TTAContext *s = avctx->priv_data; |
| |
| if (s->bps < 3) |
| av_free(s->decode_buffer); |
| s->decode_buffer = NULL; |
| av_freep(&s->ch_ctx); |
| |
| return 0; |
| } |
| |
| AVCodec ff_tta_decoder = { |
| .name = "tta", |
| .type = AVMEDIA_TYPE_AUDIO, |
| .id = AV_CODEC_ID_TTA, |
| .priv_data_size = sizeof(TTAContext), |
| .init = tta_decode_init, |
| .close = tta_decode_close, |
| .decode = tta_decode_frame, |
| .capabilities = CODEC_CAP_DR1, |
| .long_name = NULL_IF_CONFIG_SMALL("TTA (True Audio)"), |
| }; |