| /* |
| * DCA parser |
| * Copyright (C) 2004 Gildas Bazin |
| * Copyright (C) 2004 Benjamin Zores |
| * Copyright (C) 2006 Benjamin Larsson |
| * Copyright (C) 2007 Konstantin Shishkov |
| * |
| * 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 |
| */ |
| |
| #include "dca.h" |
| #include "dca_core.h" |
| #include "dca_exss.h" |
| #include "dca_lbr.h" |
| #include "dca_syncwords.h" |
| #include "get_bits.h" |
| #include "parser.h" |
| |
| typedef struct DCAParseContext { |
| ParseContext pc; |
| uint32_t lastmarker; |
| int size; |
| int framesize; |
| unsigned int startpos; |
| DCAExssParser exss; |
| unsigned int sr_code; |
| } DCAParseContext; |
| |
| #define IS_CORE_MARKER(state) \ |
| (((state & 0xFFFFFFFFF0FF) == (((uint64_t)DCA_SYNCWORD_CORE_14B_LE << 16) | 0xF007)) || \ |
| ((state & 0xFFFFFFFFFFF0) == (((uint64_t)DCA_SYNCWORD_CORE_14B_BE << 16) | 0x07F0)) || \ |
| ((state & 0xFFFFFFFF00FC) == (((uint64_t)DCA_SYNCWORD_CORE_LE << 16) | 0x00FC)) || \ |
| ((state & 0xFFFFFFFFFC00) == (((uint64_t)DCA_SYNCWORD_CORE_BE << 16) | 0xFC00))) |
| |
| #define IS_EXSS_MARKER(state) ((state & 0xFFFFFFFF) == DCA_SYNCWORD_SUBSTREAM) |
| |
| #define IS_MARKER(state) (IS_CORE_MARKER(state) || IS_EXSS_MARKER(state)) |
| |
| #define CORE_MARKER(state) ((state >> 16) & 0xFFFFFFFF) |
| #define EXSS_MARKER(state) (state & 0xFFFFFFFF) |
| |
| #define STATE_LE(state) (((state & 0xFF00FF00) >> 8) | ((state & 0x00FF00FF) << 8)) |
| #define STATE_14(state) (((state & 0x3FFF0000) >> 8) | ((state & 0x00003FFF) >> 6)) |
| |
| #define CORE_FRAMESIZE(state) (((state >> 4) & 0x3FFF) + 1) |
| #define EXSS_FRAMESIZE(state) ((state & 0x2000000000) ? \ |
| ((state >> 5) & 0xFFFFF) + 1 : \ |
| ((state >> 13) & 0x0FFFF) + 1) |
| |
| /** |
| * Find the end of the current frame in the bitstream. |
| * @return the position of the first byte of the next frame, or -1 |
| */ |
| static int dca_find_frame_end(DCAParseContext *pc1, const uint8_t *buf, |
| int buf_size) |
| { |
| int start_found, size, i; |
| uint64_t state; |
| ParseContext *pc = &pc1->pc; |
| |
| start_found = pc->frame_start_found; |
| state = pc->state64; |
| size = pc1->size; |
| |
| i = 0; |
| if (!start_found) { |
| for (; i < buf_size; i++) { |
| size++; |
| state = (state << 8) | buf[i]; |
| |
| if (IS_MARKER(state) && |
| (!pc1->lastmarker || |
| pc1->lastmarker == CORE_MARKER(state) || |
| pc1->lastmarker == DCA_SYNCWORD_SUBSTREAM)) { |
| if (!pc1->lastmarker) |
| pc1->startpos = IS_EXSS_MARKER(state) ? size - 4 : size - 6; |
| |
| if (IS_EXSS_MARKER(state)) |
| pc1->lastmarker = EXSS_MARKER(state); |
| else |
| pc1->lastmarker = CORE_MARKER(state); |
| |
| start_found = 1; |
| size = 0; |
| |
| i++; |
| break; |
| } |
| } |
| } |
| |
| if (start_found) { |
| for (; i < buf_size; i++) { |
| size++; |
| state = (state << 8) | buf[i]; |
| |
| if (start_found == 1) { |
| switch (pc1->lastmarker) { |
| case DCA_SYNCWORD_CORE_BE: |
| if (size == 2) { |
| pc1->framesize = CORE_FRAMESIZE(state); |
| start_found = 2; |
| } |
| break; |
| case DCA_SYNCWORD_CORE_LE: |
| if (size == 2) { |
| pc1->framesize = CORE_FRAMESIZE(STATE_LE(state)); |
| start_found = 4; |
| } |
| break; |
| case DCA_SYNCWORD_CORE_14B_BE: |
| if (size == 4) { |
| pc1->framesize = CORE_FRAMESIZE(STATE_14(state)); |
| start_found = 4; |
| } |
| break; |
| case DCA_SYNCWORD_CORE_14B_LE: |
| if (size == 4) { |
| pc1->framesize = CORE_FRAMESIZE(STATE_14(STATE_LE(state))); |
| start_found = 4; |
| } |
| break; |
| case DCA_SYNCWORD_SUBSTREAM: |
| if (size == 6) { |
| pc1->framesize = EXSS_FRAMESIZE(state); |
| start_found = 4; |
| } |
| break; |
| default: |
| av_assert0(0); |
| } |
| continue; |
| } |
| |
| if (start_found == 2 && IS_EXSS_MARKER(state) && |
| pc1->framesize <= size + 2) { |
| pc1->framesize = size + 2; |
| start_found = 3; |
| continue; |
| } |
| |
| if (start_found == 3) { |
| if (size == pc1->framesize + 4) { |
| pc1->framesize += EXSS_FRAMESIZE(state); |
| start_found = 4; |
| } |
| continue; |
| } |
| |
| if (pc1->framesize > size) |
| continue; |
| |
| if (IS_MARKER(state) && |
| (pc1->lastmarker == CORE_MARKER(state) || |
| pc1->lastmarker == DCA_SYNCWORD_SUBSTREAM)) { |
| pc->frame_start_found = 0; |
| pc->state64 = -1; |
| pc1->size = 0; |
| return IS_EXSS_MARKER(state) ? i - 3 : i - 5; |
| } |
| } |
| } |
| |
| pc->frame_start_found = start_found; |
| pc->state64 = state; |
| pc1->size = size; |
| return END_NOT_FOUND; |
| } |
| |
| static av_cold int dca_parse_init(AVCodecParserContext *s) |
| { |
| DCAParseContext *pc1 = s->priv_data; |
| |
| pc1->lastmarker = 0; |
| pc1->sr_code = -1; |
| return 0; |
| } |
| |
| static int dca_parse_params(DCAParseContext *pc1, const uint8_t *buf, |
| int buf_size, int *duration, int *sample_rate, |
| int *profile) |
| { |
| DCAExssAsset *asset = &pc1->exss.assets[0]; |
| GetBitContext gb; |
| DCACoreFrameHeader h; |
| uint8_t hdr[DCA_CORE_FRAME_HEADER_SIZE + AV_INPUT_BUFFER_PADDING_SIZE] = { 0 }; |
| int ret, frame_size; |
| |
| if (buf_size < DCA_CORE_FRAME_HEADER_SIZE) |
| return AVERROR_INVALIDDATA; |
| |
| if (AV_RB32(buf) == DCA_SYNCWORD_SUBSTREAM) { |
| if ((ret = ff_dca_exss_parse(&pc1->exss, buf, buf_size)) < 0) |
| return ret; |
| |
| if (asset->extension_mask & DCA_EXSS_LBR) { |
| if ((ret = init_get_bits8(&gb, buf + asset->lbr_offset, asset->lbr_size)) < 0) |
| return ret; |
| |
| if (get_bits_long(&gb, 32) != DCA_SYNCWORD_LBR) |
| return AVERROR_INVALIDDATA; |
| |
| switch (get_bits(&gb, 8)) { |
| case DCA_LBR_HEADER_DECODER_INIT: |
| pc1->sr_code = get_bits(&gb, 8); |
| case DCA_LBR_HEADER_SYNC_ONLY: |
| break; |
| default: |
| return AVERROR_INVALIDDATA; |
| } |
| |
| if (pc1->sr_code >= FF_ARRAY_ELEMS(ff_dca_sampling_freqs)) |
| return AVERROR_INVALIDDATA; |
| |
| *sample_rate = ff_dca_sampling_freqs[pc1->sr_code]; |
| *duration = 1024 << ff_dca_freq_ranges[pc1->sr_code]; |
| *profile = FF_PROFILE_DTS_EXPRESS; |
| return 0; |
| } |
| |
| if (asset->extension_mask & DCA_EXSS_XLL) { |
| int nsamples_log2; |
| |
| if ((ret = init_get_bits8(&gb, buf + asset->xll_offset, asset->xll_size)) < 0) |
| return ret; |
| |
| if (get_bits_long(&gb, 32) != DCA_SYNCWORD_XLL) |
| return AVERROR_INVALIDDATA; |
| |
| if (get_bits(&gb, 4)) |
| return AVERROR_INVALIDDATA; |
| |
| skip_bits(&gb, 8); |
| skip_bits_long(&gb, get_bits(&gb, 5) + 1); |
| skip_bits(&gb, 4); |
| nsamples_log2 = get_bits(&gb, 4) + get_bits(&gb, 4); |
| if (nsamples_log2 > 24) |
| return AVERROR_INVALIDDATA; |
| |
| *sample_rate = asset->max_sample_rate; |
| *duration = (1 + (*sample_rate > 96000)) << nsamples_log2; |
| *profile = FF_PROFILE_DTS_HD_MA; |
| return 0; |
| } |
| |
| return AVERROR_INVALIDDATA; |
| } |
| |
| if ((ret = avpriv_dca_convert_bitstream(buf, DCA_CORE_FRAME_HEADER_SIZE, |
| hdr, DCA_CORE_FRAME_HEADER_SIZE)) < 0) |
| return ret; |
| if (avpriv_dca_parse_core_frame_header(&h, hdr, ret) < 0) |
| return AVERROR_INVALIDDATA; |
| |
| *duration = h.npcmblocks * DCA_PCMBLOCK_SAMPLES; |
| *sample_rate = avpriv_dca_sample_rates[h.sr_code]; |
| if (*profile != FF_PROFILE_UNKNOWN) |
| return 0; |
| |
| *profile = FF_PROFILE_DTS; |
| if (h.ext_audio_present) { |
| switch (h.ext_audio_type) { |
| case DCA_EXT_AUDIO_XCH: |
| case DCA_EXT_AUDIO_XXCH: |
| *profile = FF_PROFILE_DTS_ES; |
| break; |
| case DCA_EXT_AUDIO_X96: |
| *profile = FF_PROFILE_DTS_96_24; |
| break; |
| } |
| } |
| |
| frame_size = FFALIGN(h.frame_size, 4); |
| if (buf_size - 4 < frame_size) |
| return 0; |
| |
| buf += frame_size; |
| buf_size -= frame_size; |
| if (AV_RB32(buf) != DCA_SYNCWORD_SUBSTREAM) |
| return 0; |
| if (ff_dca_exss_parse(&pc1->exss, buf, buf_size) < 0) |
| return 0; |
| |
| if (asset->extension_mask & DCA_EXSS_XLL) |
| *profile = FF_PROFILE_DTS_HD_MA; |
| else if (asset->extension_mask & (DCA_EXSS_XBR | DCA_EXSS_XXCH | DCA_EXSS_X96)) |
| *profile = FF_PROFILE_DTS_HD_HRA; |
| |
| return 0; |
| } |
| |
| static int dca_parse(AVCodecParserContext *s, AVCodecContext *avctx, |
| const uint8_t **poutbuf, int *poutbuf_size, |
| const uint8_t *buf, int buf_size) |
| { |
| DCAParseContext *pc1 = s->priv_data; |
| ParseContext *pc = &pc1->pc; |
| int next, duration, sample_rate; |
| |
| if (s->flags & PARSER_FLAG_COMPLETE_FRAMES) { |
| next = buf_size; |
| } else { |
| next = dca_find_frame_end(pc1, buf, buf_size); |
| |
| if (ff_combine_frame(pc, next, &buf, &buf_size) < 0) { |
| *poutbuf = NULL; |
| *poutbuf_size = 0; |
| return buf_size; |
| } |
| |
| /* skip initial padding */ |
| if (buf_size > pc1->startpos) { |
| buf += pc1->startpos; |
| buf_size -= pc1->startpos; |
| } |
| pc1->startpos = 0; |
| } |
| |
| /* read the duration and sample rate from the frame header */ |
| if (!dca_parse_params(pc1, buf, buf_size, &duration, &sample_rate, &avctx->profile)) { |
| if (!avctx->sample_rate) |
| avctx->sample_rate = sample_rate; |
| s->duration = av_rescale(duration, avctx->sample_rate, sample_rate); |
| } else |
| s->duration = 0; |
| |
| *poutbuf = buf; |
| *poutbuf_size = buf_size; |
| return next; |
| } |
| |
| AVCodecParser ff_dca_parser = { |
| .codec_ids = { AV_CODEC_ID_DTS }, |
| .priv_data_size = sizeof(DCAParseContext), |
| .parser_init = dca_parse_init, |
| .parser_parse = dca_parse, |
| .parser_close = ff_parse_close, |
| }; |