/* * 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 = AV_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 = AV_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 = ff_dca_sample_rates[h.sr_code];    if (*profile != AV_PROFILE_UNKNOWN)        return 0;     *profile = AV_PROFILE_DTS;    if (h.ext_audio_present) {        switch (h.ext_audio_type) {        case DCA_EXT_AUDIO_XCH:        case DCA_EXT_AUDIO_XXCH:            *profile = AV_PROFILE_DTS_ES;            break;        case DCA_EXT_AUDIO_X96:            *profile = AV_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 = AV_PROFILE_DTS_HD_MA;    else if (asset->extension_mask & (DCA_EXSS_XBR | DCA_EXSS_XXCH | DCA_EXSS_X96))        *profile = AV_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;} const 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,};