📄 mp4atom.c
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/*** FAAD2 - Freeware Advanced Audio (AAC) Decoder including SBR decoding** Copyright (C) 2003-2004 M. Bakker, Ahead Software AG, http://www.nero.com**** This program is free software; you can redistribute it and/or modify** it under the terms of the GNU General Public License as published by** the Free Software Foundation; either version 2 of the License, or** (at your option) any later version.**** This program 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 General Public License for more details.**** You should have received a copy of the GNU General Public License** along with this program; if not, write to the Free Software** Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.**** Any non-GPL usage of this software or parts of this software is strictly** forbidden.**** Commercial non-GPL licensing of this software is possible.** For more info contact Ahead Software through Mpeg4AAClicense@nero.com.**** $Id: mp4atom.c,v 1.1 2006/02/23 14:32:29 kevin-fu Exp $**/#include <stdlib.h>#include "mp4ffint.h"#include "drms.h"/* parse atom header size */static int32_t mp4ff_atom_get_size(const int8_t *data){ uint32_t result; uint32_t a, b, c, d; a = (uint8_t)data[0]; b = (uint8_t)data[1]; c = (uint8_t)data[2]; d = (uint8_t)data[3]; result = (a<<24) | (b<<16) | (c<<8) | d; //if (result > 0 && result < 8) result = 8; return (int32_t)result;}/* comnapre 2 atom names, returns 1 for equal, 0 for unequal */static int32_t mp4ff_atom_compare(const int8_t a1, const int8_t b1, const int8_t c1, const int8_t d1, const int8_t a2, const int8_t b2, const int8_t c2, const int8_t d2){ if (a1 == a2 && b1 == b2 && c1 == c2 && d1 == d2) return 1; else return 0;}static uint8_t mp4ff_atom_name_to_type(const int8_t a, const int8_t b, const int8_t c, const int8_t d){ if (a == 'm') { if (mp4ff_atom_compare(a,b,c,d, 'm','o','o','v')) return ATOM_MOOV; else if (mp4ff_atom_compare(a,b,c,d, 'm','i','n','f')) return ATOM_MINF; else if (mp4ff_atom_compare(a,b,c,d, 'm','d','i','a')) return ATOM_MDIA; else if (mp4ff_atom_compare(a,b,c,d, 'm','d','a','t')) return ATOM_MDAT; else if (mp4ff_atom_compare(a,b,c,d, 'm','d','h','d')) return ATOM_MDHD; else if (mp4ff_atom_compare(a,b,c,d, 'm','v','h','d')) return ATOM_MVHD; else if (mp4ff_atom_compare(a,b,c,d, 'm','p','4','a')) return ATOM_MP4A; else if (mp4ff_atom_compare(a,b,c,d, 'm','p','4','v')) return ATOM_MP4V; else if (mp4ff_atom_compare(a,b,c,d, 'm','p','4','s')) return ATOM_MP4S; else if (mp4ff_atom_compare(a,b,c,d, 'm','e','t','a')) return ATOM_META; } else if (a == 't') { if (mp4ff_atom_compare(a,b,c,d, 't','r','a','k')) return ATOM_TRAK; else if (mp4ff_atom_compare(a,b,c,d, 't','k','h','d')) return ATOM_TKHD; else if (mp4ff_atom_compare(a,b,c,d, 't','r','e','f')) return ATOM_TREF; else if (mp4ff_atom_compare(a,b,c,d, 't','r','k','n')) return ATOM_TRACK; else if (mp4ff_atom_compare(a,b,c,d, 't','m','p','o')) return ATOM_TEMPO; } else if (a == 's') { if (mp4ff_atom_compare(a,b,c,d, 's','t','b','l')) return ATOM_STBL; else if (mp4ff_atom_compare(a,b,c,d, 's','m','h','d')) return ATOM_SMHD; else if (mp4ff_atom_compare(a,b,c,d, 's','t','s','d')) return ATOM_STSD; else if (mp4ff_atom_compare(a,b,c,d, 's','t','t','s')) return ATOM_STTS; else if (mp4ff_atom_compare(a,b,c,d, 's','t','c','o')) return ATOM_STCO; else if (mp4ff_atom_compare(a,b,c,d, 's','t','s','c')) return ATOM_STSC; else if (mp4ff_atom_compare(a,b,c,d, 's','t','s','z')) return ATOM_STSZ; else if (mp4ff_atom_compare(a,b,c,d, 's','t','z','2')) return ATOM_STZ2; else if (mp4ff_atom_compare(a,b,c,d, 's','k','i','p')) return ATOM_SKIP; else if (mp4ff_atom_compare(a,b,c,d, 's','i','n','f')) return ATOM_SINF; else if (mp4ff_atom_compare(a,b,c,d, 's','c','h','i')) return ATOM_SCHI; } else if (a == '?') { if (mp4ff_atom_compare(a,b,c,d, '?','n','a','m')) return ATOM_TITLE; else if (mp4ff_atom_compare(a,b,c,d, '?','A','R','T')) return ATOM_ARTIST; else if (mp4ff_atom_compare(a,b,c,d, '?','w','r','t')) return ATOM_WRITER; else if (mp4ff_atom_compare(a,b,c,d, '?','a','l','b')) return ATOM_ALBUM; else if (mp4ff_atom_compare(a,b,c,d, '?','d','a','y')) return ATOM_DATE; else if (mp4ff_atom_compare(a,b,c,d, '?','t','o','o')) return ATOM_TOOL; else if (mp4ff_atom_compare(a,b,c,d, '?','c','m','t')) return ATOM_COMMENT; else if (mp4ff_atom_compare(a,b,c,d, '?','g','e','n')) return ATOM_GENRE1; } if (mp4ff_atom_compare(a,b,c,d, 'e','d','t','s')) return ATOM_EDTS; else if (mp4ff_atom_compare(a,b,c,d, 'e','s','d','s')) return ATOM_ESDS; else if (mp4ff_atom_compare(a,b,c,d, 'f','t','y','p')) return ATOM_FTYP; else if (mp4ff_atom_compare(a,b,c,d, 'f','r','e','e')) return ATOM_FREE; else if (mp4ff_atom_compare(a,b,c,d, 'h','m','h','d')) return ATOM_HMHD; else if (mp4ff_atom_compare(a,b,c,d, 'v','m','h','d')) return ATOM_VMHD; else if (mp4ff_atom_compare(a,b,c,d, 'u','d','t','a')) return ATOM_UDTA; else if (mp4ff_atom_compare(a,b,c,d, 'i','l','s','t')) return ATOM_ILST; else if (mp4ff_atom_compare(a,b,c,d, 'n','a','m','e')) return ATOM_NAME; else if (mp4ff_atom_compare(a,b,c,d, 'd','a','t','a')) return ATOM_DATA; else if (mp4ff_atom_compare(a,b,c,d, 'd','i','s','k')) return ATOM_DISC; else if (mp4ff_atom_compare(a,b,c,d, 'g','n','r','e')) return ATOM_GENRE2; else if (mp4ff_atom_compare(a,b,c,d, 'c','o','v','r')) return ATOM_COVER; else if (mp4ff_atom_compare(a,b,c,d, 'c','p','i','l')) return ATOM_COMPILATION; else if (mp4ff_atom_compare(a,b,c,d, 'c','t','t','s')) return ATOM_CTTS; else if (mp4ff_atom_compare(a,b,c,d, 'd','r','m','s')) return ATOM_DRMS; else if (mp4ff_atom_compare(a,b,c,d, 'f','r','m','a')) return ATOM_FRMA; else if (mp4ff_atom_compare(a,b,c,d, 'p','r','i','v')) return ATOM_PRIV; else if (mp4ff_atom_compare(a,b,c,d, 'i','v','i','v')) return ATOM_IVIV; else return ATOM_UNKNOWN;}/* read atom header, return atom size, atom size is with header included */uint64_t mp4ff_atom_read_header(mp4ff_t *f, uint8_t *atom_type, uint8_t *header_size){ uint64_t size; int32_t ret; int8_t atom_header[8]; ret = mp4ff_read_data(f, atom_header, 8); if (ret != 8) return 0; size = mp4ff_atom_get_size(atom_header); *header_size = 8; /* check for 64 bit atom size */ if (size == 1) { *header_size = 16; size = mp4ff_read_int64(f); } //printf("%c%c%c%c\n", atom_header[4], atom_header[5], atom_header[6], atom_header[7]); *atom_type = mp4ff_atom_name_to_type(atom_header[4], atom_header[5], atom_header[6], atom_header[7]); return size;}static int32_t mp4ff_read_stsz(mp4ff_t *f){ mp4ff_read_char(f); /* version */ mp4ff_read_int24(f); /* flags */ f->track[f->total_tracks - 1]->stsz_sample_size = mp4ff_read_int32(f); f->track[f->total_tracks - 1]->stsz_sample_count = mp4ff_read_int32(f); if (f->track[f->total_tracks - 1]->stsz_sample_size == 0) { int32_t i; f->track[f->total_tracks - 1]->stsz_table = (int32_t*)malloc(f->track[f->total_tracks - 1]->stsz_sample_count*sizeof(int32_t)); for (i = 0; i < f->track[f->total_tracks - 1]->stsz_sample_count; i++) { f->track[f->total_tracks - 1]->stsz_table[i] = mp4ff_read_int32(f); } } return 0;}static int32_t mp4ff_read_esds(mp4ff_t *f){ uint8_t tag; uint32_t temp; mp4ff_read_char(f); /* version */ mp4ff_read_int24(f); /* flags */ /* get and verify ES_DescrTag */ tag = mp4ff_read_char(f); if (tag == 0x03) { /* read length */ if (mp4ff_read_mp4_descr_length(f) < 5 + 15) { return 1; } /* skip 3 bytes */ mp4ff_read_int24(f); } else { /* skip 2 bytes */ mp4ff_read_int16(f); } /* get and verify DecoderConfigDescrTab */ if (mp4ff_read_char(f) != 0x04) { return 1; } /* read length */ temp = mp4ff_read_mp4_descr_length(f); if (temp < 13) return 1; f->track[f->total_tracks - 1]->audioType = mp4ff_read_char(f); mp4ff_read_int32(f);//0x15000414 ???? f->track[f->total_tracks - 1]->maxBitrate = mp4ff_read_int32(f); f->track[f->total_tracks - 1]->avgBitrate = mp4ff_read_int32(f); /* get and verify DecSpecificInfoTag */ if (mp4ff_read_char(f) != 0x05) { return 1; } /* read length */ f->track[f->total_tracks - 1]->decoderConfigLen = mp4ff_read_mp4_descr_length(f); if (f->track[f->total_tracks - 1]->decoderConfig) free(f->track[f->total_tracks - 1]->decoderConfig); f->track[f->total_tracks - 1]->decoderConfig = malloc(f->track[f->total_tracks - 1]->decoderConfigLen); if (f->track[f->total_tracks - 1]->decoderConfig) { mp4ff_read_data(f, f->track[f->total_tracks - 1]->decoderConfig, f->track[f->total_tracks - 1]->decoderConfigLen); } else { f->track[f->total_tracks - 1]->decoderConfigLen = 0; } /* will skip the remainder of the atom */ return 0;}static int32_t mp4ff_read_mp4a(mp4ff_t *f){ uint64_t size; int32_t i; uint8_t atom_type = 0; uint8_t header_size = 0; for (i = 0; i < 6; i++) { mp4ff_read_char(f); /* reserved */ } /* data_reference_index */ mp4ff_read_int16(f); mp4ff_read_int32(f); /* reserved */ mp4ff_read_int32(f); /* reserved */ f->track[f->total_tracks - 1]->channelCount = mp4ff_read_int16(f); f->track[f->total_tracks - 1]->sampleSize = mp4ff_read_int16(f); mp4ff_read_int16(f); mp4ff_read_int16(f); f->track[f->total_tracks - 1]->sampleRate = mp4ff_read_int16(f); mp4ff_read_int16(f); size = mp4ff_atom_read_header(f, &atom_type, &header_size); if (atom_type == ATOM_ESDS) { mp4ff_read_esds(f); } return 0;}#ifdef ITUNES_DRMstatic int32_t mp4ff_read_drms(mp4ff_t *f, uint64_t skip){ uint64_t size; int32_t i; uint8_t atom_type = 0; uint8_t header_size = 0; uint32_t drms_user_key[4]; if (drms_get_user_key(NULL, drms_user_key) == 0) { f->track[f->total_tracks - 1]->p_drms = drms_alloc(); drms_init( f->track[f->total_tracks - 1]->p_drms, DRMS_INIT_UKEY, (uint8_t *)drms_user_key, sizeof(drms_user_key) ); } for (i = 0; i < 6; i++) { mp4ff_read_char(f); /* reserved */ } /* data_reference_index */ mp4ff_read_int16(f); mp4ff_read_int32(f); /* reserved */ mp4ff_read_int32(f); /* reserved */ f->track[f->total_tracks - 1]->channelCount = mp4ff_read_int16(f); f->track[f->total_tracks - 1]->sampleSize = mp4ff_read_int16(f); mp4ff_read_int16(f); mp4ff_read_int16(f); f->track[f->total_tracks - 1]->sampleRate = mp4ff_read_int16(f); mp4ff_read_int16(f); size = mp4ff_atom_read_header(f, &atom_type, &header_size); if (atom_type == ATOM_ESDS) { mp4ff_read_esds(f); } mp4ff_set_position(f, skip+size+28); size = mp4ff_atom_read_header(f, &atom_type, &header_size); if (atom_type == ATOM_SINF) { parse_sub_atoms(f, size-header_size); } return 0;}static int32_t mp4ff_read_frma(mp4ff_t *f){ uint8_t atom_type; int8_t type[4]; mp4ff_read_data(f, type, 4); atom_type = mp4ff_atom_name_to_type(type[0], type[1], type[2], type[3]); if (atom_type == ATOM_MP4A) { f->track[f->total_tracks - 1]->type = TRACK_AUDIO;
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