yading@11: /* yading@11: * Core Audio Format demuxer yading@11: * Copyright (c) 2007 Justin Ruggles yading@11: * Copyright (c) 2009 Peter Ross yading@11: * yading@11: * This file is part of FFmpeg. yading@11: * yading@11: * FFmpeg is free software; you can redistribute it and/or yading@11: * modify it under the terms of the GNU Lesser General Public yading@11: * License as published by the Free Software Foundation; either yading@11: * version 2.1 of the License, or (at your option) any later version. yading@11: * yading@11: * FFmpeg is distributed in the hope that it will be useful, yading@11: * but WITHOUT ANY WARRANTY; without even the implied warranty of yading@11: * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU yading@11: * Lesser General Public License for more details. yading@11: * yading@11: * You should have received a copy of the GNU Lesser General Public yading@11: * License along with FFmpeg; if not, write to the Free Software yading@11: * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA yading@11: */ yading@11: yading@11: /** yading@11: * @file yading@11: * Core Audio Format demuxer yading@11: */ yading@11: yading@11: #include "avformat.h" yading@11: #include "internal.h" yading@11: #include "isom.h" yading@11: #include "mov_chan.h" yading@11: #include "libavutil/intreadwrite.h" yading@11: #include "libavutil/intfloat.h" yading@11: #include "libavutil/dict.h" yading@11: #include "caf.h" yading@11: yading@11: typedef struct { yading@11: int bytes_per_packet; ///< bytes in a packet, or 0 if variable yading@11: int frames_per_packet; ///< frames in a packet, or 0 if variable yading@11: int64_t num_bytes; ///< total number of bytes in stream yading@11: yading@11: int64_t packet_cnt; ///< packet counter yading@11: int64_t frame_cnt; ///< frame counter yading@11: yading@11: int64_t data_start; ///< data start position, in bytes yading@11: int64_t data_size; ///< raw data size, in bytes yading@11: } CaffContext; yading@11: yading@11: static int probe(AVProbeData *p) yading@11: { yading@11: if (AV_RB32(p->buf) == MKBETAG('c','a','f','f') && AV_RB16(&p->buf[4]) == 1) yading@11: return AVPROBE_SCORE_MAX; yading@11: return 0; yading@11: } yading@11: yading@11: /** Read audio description chunk */ yading@11: static int read_desc_chunk(AVFormatContext *s) yading@11: { yading@11: AVIOContext *pb = s->pb; yading@11: CaffContext *caf = s->priv_data; yading@11: AVStream *st; yading@11: int flags; yading@11: yading@11: /* new audio stream */ yading@11: st = avformat_new_stream(s, NULL); yading@11: if (!st) yading@11: return AVERROR(ENOMEM); yading@11: yading@11: /* parse format description */ yading@11: st->codec->codec_type = AVMEDIA_TYPE_AUDIO; yading@11: st->codec->sample_rate = av_int2double(avio_rb64(pb)); yading@11: st->codec->codec_tag = avio_rl32(pb); yading@11: flags = avio_rb32(pb); yading@11: caf->bytes_per_packet = avio_rb32(pb); yading@11: st->codec->block_align = caf->bytes_per_packet; yading@11: caf->frames_per_packet = avio_rb32(pb); yading@11: st->codec->channels = avio_rb32(pb); yading@11: st->codec->bits_per_coded_sample = avio_rb32(pb); yading@11: yading@11: /* calculate bit rate for constant size packets */ yading@11: if (caf->frames_per_packet > 0 && caf->bytes_per_packet > 0) { yading@11: st->codec->bit_rate = (uint64_t)st->codec->sample_rate * (uint64_t)caf->bytes_per_packet * 8 yading@11: / (uint64_t)caf->frames_per_packet; yading@11: } else { yading@11: st->codec->bit_rate = 0; yading@11: } yading@11: yading@11: /* determine codec */ yading@11: if (st->codec->codec_tag == MKTAG('l','p','c','m')) yading@11: st->codec->codec_id = ff_mov_get_lpcm_codec_id(st->codec->bits_per_coded_sample, (flags ^ 0x2) | 0x4); yading@11: else yading@11: st->codec->codec_id = ff_codec_get_id(ff_codec_caf_tags, st->codec->codec_tag); yading@11: return 0; yading@11: } yading@11: yading@11: /** Read magic cookie chunk */ yading@11: static int read_kuki_chunk(AVFormatContext *s, int64_t size) yading@11: { yading@11: AVIOContext *pb = s->pb; yading@11: AVStream *st = s->streams[0]; yading@11: yading@11: if (size < 0 || size > INT_MAX - FF_INPUT_BUFFER_PADDING_SIZE) yading@11: return -1; yading@11: yading@11: if (st->codec->codec_id == AV_CODEC_ID_AAC) { yading@11: /* The magic cookie format for AAC is an mp4 esds atom. yading@11: The lavc AAC decoder requires the data from the codec specific yading@11: description as extradata input. */ yading@11: int strt, skip; yading@11: MOVAtom atom; yading@11: yading@11: strt = avio_tell(pb); yading@11: ff_mov_read_esds(s, pb, atom); yading@11: skip = size - (avio_tell(pb) - strt); yading@11: if (skip < 0 || !st->codec->extradata || yading@11: st->codec->codec_id != AV_CODEC_ID_AAC) { yading@11: av_log(s, AV_LOG_ERROR, "invalid AAC magic cookie\n"); yading@11: return AVERROR_INVALIDDATA; yading@11: } yading@11: avio_skip(pb, skip); yading@11: } else if (st->codec->codec_id == AV_CODEC_ID_ALAC) { yading@11: #define ALAC_PREAMBLE 12 yading@11: #define ALAC_HEADER 36 yading@11: #define ALAC_NEW_KUKI 24 yading@11: uint8_t preamble[12]; yading@11: if (size < ALAC_NEW_KUKI) { yading@11: av_log(s, AV_LOG_ERROR, "invalid ALAC magic cookie\n"); yading@11: avio_skip(pb, size); yading@11: return AVERROR_INVALIDDATA; yading@11: } yading@11: avio_read(pb, preamble, ALAC_PREAMBLE); yading@11: yading@11: st->codec->extradata = av_mallocz(ALAC_HEADER + FF_INPUT_BUFFER_PADDING_SIZE); yading@11: if (!st->codec->extradata) yading@11: return AVERROR(ENOMEM); yading@11: yading@11: /* For the old style cookie, we skip 12 bytes, then read 36 bytes. yading@11: * The new style cookie only contains the last 24 bytes of what was yading@11: * 36 bytes in the old style cookie, so we fabricate the first 12 bytes yading@11: * in that case to maintain compatibility. */ yading@11: if (!memcmp(&preamble[4], "frmaalac", 8)) { yading@11: if (size < ALAC_PREAMBLE + ALAC_HEADER) { yading@11: av_log(s, AV_LOG_ERROR, "invalid ALAC magic cookie\n"); yading@11: av_freep(&st->codec->extradata); yading@11: return AVERROR_INVALIDDATA; yading@11: } yading@11: avio_read(pb, st->codec->extradata, ALAC_HEADER); yading@11: avio_skip(pb, size - ALAC_PREAMBLE - ALAC_HEADER); yading@11: } else { yading@11: AV_WB32(st->codec->extradata, 36); yading@11: memcpy(&st->codec->extradata[4], "alac", 4); yading@11: AV_WB32(&st->codec->extradata[8], 0); yading@11: memcpy(&st->codec->extradata[12], preamble, 12); yading@11: avio_read(pb, &st->codec->extradata[24], ALAC_NEW_KUKI - 12); yading@11: avio_skip(pb, size - ALAC_NEW_KUKI); yading@11: } yading@11: st->codec->extradata_size = ALAC_HEADER; yading@11: } else { yading@11: st->codec->extradata = av_mallocz(size + FF_INPUT_BUFFER_PADDING_SIZE); yading@11: if (!st->codec->extradata) yading@11: return AVERROR(ENOMEM); yading@11: avio_read(pb, st->codec->extradata, size); yading@11: st->codec->extradata_size = size; yading@11: } yading@11: yading@11: return 0; yading@11: } yading@11: yading@11: /** Read packet table chunk */ yading@11: static int read_pakt_chunk(AVFormatContext *s, int64_t size) yading@11: { yading@11: AVIOContext *pb = s->pb; yading@11: AVStream *st = s->streams[0]; yading@11: CaffContext *caf = s->priv_data; yading@11: int64_t pos = 0, ccount, num_packets; yading@11: int i; yading@11: yading@11: ccount = avio_tell(pb); yading@11: yading@11: num_packets = avio_rb64(pb); yading@11: if (num_packets < 0 || INT32_MAX / sizeof(AVIndexEntry) < num_packets) yading@11: return AVERROR_INVALIDDATA; yading@11: yading@11: st->nb_frames = avio_rb64(pb); /* valid frames */ yading@11: st->nb_frames += avio_rb32(pb); /* priming frames */ yading@11: st->nb_frames += avio_rb32(pb); /* remainder frames */ yading@11: yading@11: st->duration = 0; yading@11: for (i = 0; i < num_packets; i++) { yading@11: av_add_index_entry(s->streams[0], pos, st->duration, 0, 0, AVINDEX_KEYFRAME); yading@11: pos += caf->bytes_per_packet ? caf->bytes_per_packet : ff_mp4_read_descr_len(pb); yading@11: st->duration += caf->frames_per_packet ? caf->frames_per_packet : ff_mp4_read_descr_len(pb); yading@11: } yading@11: yading@11: if (avio_tell(pb) - ccount > size) { yading@11: av_log(s, AV_LOG_ERROR, "error reading packet table\n"); yading@11: return AVERROR_INVALIDDATA; yading@11: } yading@11: avio_skip(pb, ccount + size - avio_tell(pb)); yading@11: yading@11: caf->num_bytes = pos; yading@11: return 0; yading@11: } yading@11: yading@11: /** Read information chunk */ yading@11: static void read_info_chunk(AVFormatContext *s, int64_t size) yading@11: { yading@11: AVIOContext *pb = s->pb; yading@11: unsigned int i; yading@11: unsigned int nb_entries = avio_rb32(pb); yading@11: for (i = 0; i < nb_entries; i++) { yading@11: char key[32]; yading@11: char value[1024]; yading@11: avio_get_str(pb, INT_MAX, key, sizeof(key)); yading@11: avio_get_str(pb, INT_MAX, value, sizeof(value)); yading@11: av_dict_set(&s->metadata, key, value, 0); yading@11: } yading@11: } yading@11: yading@11: static int read_header(AVFormatContext *s) yading@11: { yading@11: AVIOContext *pb = s->pb; yading@11: CaffContext *caf = s->priv_data; yading@11: AVStream *st; yading@11: uint32_t tag = 0; yading@11: int found_data, ret; yading@11: int64_t size, pos; yading@11: yading@11: avio_skip(pb, 8); /* magic, version, file flags */ yading@11: yading@11: /* audio description chunk */ yading@11: if (avio_rb32(pb) != MKBETAG('d','e','s','c')) { yading@11: av_log(s, AV_LOG_ERROR, "desc chunk not present\n"); yading@11: return AVERROR_INVALIDDATA; yading@11: } yading@11: size = avio_rb64(pb); yading@11: if (size != 32) yading@11: return AVERROR_INVALIDDATA; yading@11: yading@11: ret = read_desc_chunk(s); yading@11: if (ret) yading@11: return ret; yading@11: st = s->streams[0]; yading@11: yading@11: /* parse each chunk */ yading@11: found_data = 0; yading@11: while (!url_feof(pb)) { yading@11: yading@11: /* stop at data chunk if seeking is not supported or yading@11: data chunk size is unknown */ yading@11: if (found_data && (caf->data_size < 0 || !pb->seekable)) yading@11: break; yading@11: yading@11: tag = avio_rb32(pb); yading@11: size = avio_rb64(pb); yading@11: pos = avio_tell(pb); yading@11: if (url_feof(pb)) yading@11: break; yading@11: yading@11: switch (tag) { yading@11: case MKBETAG('d','a','t','a'): yading@11: avio_skip(pb, 4); /* edit count */ yading@11: caf->data_start = avio_tell(pb); yading@11: caf->data_size = size < 0 ? -1 : size - 4; yading@11: if (caf->data_size > 0 && pb->seekable) yading@11: avio_skip(pb, caf->data_size); yading@11: found_data = 1; yading@11: break; yading@11: yading@11: case MKBETAG('c','h','a','n'): yading@11: if ((ret = ff_mov_read_chan(s, s->pb, st, size)) < 0) yading@11: return ret; yading@11: break; yading@11: yading@11: /* magic cookie chunk */ yading@11: case MKBETAG('k','u','k','i'): yading@11: if (read_kuki_chunk(s, size)) yading@11: return AVERROR_INVALIDDATA; yading@11: break; yading@11: yading@11: /* packet table chunk */ yading@11: case MKBETAG('p','a','k','t'): yading@11: if (read_pakt_chunk(s, size)) yading@11: return AVERROR_INVALIDDATA; yading@11: break; yading@11: yading@11: case MKBETAG('i','n','f','o'): yading@11: read_info_chunk(s, size); yading@11: break; yading@11: yading@11: default: yading@11: #define _(x) ((x) >= ' ' ? (x) : ' ') yading@11: av_log(s, AV_LOG_WARNING, "skipping CAF chunk: %08X (%c%c%c%c), size %"PRId64"\n", yading@11: tag, _(tag>>24), _((tag>>16)&0xFF), _((tag>>8)&0xFF), _(tag&0xFF), size); yading@11: #undef _ yading@11: case MKBETAG('f','r','e','e'): yading@11: if (size < 0) yading@11: return AVERROR_INVALIDDATA; yading@11: break; yading@11: } yading@11: yading@11: if (size > 0) { yading@11: if (pos > INT64_MAX - size) yading@11: return AVERROR_INVALIDDATA; yading@11: avio_skip(pb, FFMAX(0, pos + size - avio_tell(pb))); yading@11: } yading@11: } yading@11: yading@11: if (!found_data) yading@11: return AVERROR_INVALIDDATA; yading@11: yading@11: if (caf->bytes_per_packet > 0 && caf->frames_per_packet > 0) { yading@11: if (caf->data_size > 0) yading@11: st->nb_frames = (caf->data_size / caf->bytes_per_packet) * caf->frames_per_packet; yading@11: } else if (st->nb_index_entries && st->duration > 0) { yading@11: st->codec->bit_rate = st->codec->sample_rate * caf->data_size * 8 / yading@11: st->duration; yading@11: } else { yading@11: av_log(s, AV_LOG_ERROR, "Missing packet table. It is required when " yading@11: "block size or frame size are variable.\n"); yading@11: return AVERROR_INVALIDDATA; yading@11: } yading@11: yading@11: avpriv_set_pts_info(st, 64, 1, st->codec->sample_rate); yading@11: st->start_time = 0; yading@11: yading@11: /* position the stream at the start of data */ yading@11: if (caf->data_size >= 0) yading@11: avio_seek(pb, caf->data_start, SEEK_SET); yading@11: yading@11: return 0; yading@11: } yading@11: yading@11: #define CAF_MAX_PKT_SIZE 4096 yading@11: yading@11: static int read_packet(AVFormatContext *s, AVPacket *pkt) yading@11: { yading@11: AVIOContext *pb = s->pb; yading@11: AVStream *st = s->streams[0]; yading@11: CaffContext *caf = s->priv_data; yading@11: int res, pkt_size = 0, pkt_frames = 0; yading@11: int64_t left = CAF_MAX_PKT_SIZE; yading@11: yading@11: if (url_feof(pb)) yading@11: return AVERROR_EOF; yading@11: yading@11: /* don't read past end of data chunk */ yading@11: if (caf->data_size > 0) { yading@11: left = (caf->data_start + caf->data_size) - avio_tell(pb); yading@11: if (!left) yading@11: return AVERROR_EOF; yading@11: if (left < 0) yading@11: return AVERROR(EIO); yading@11: } yading@11: yading@11: pkt_frames = caf->frames_per_packet; yading@11: pkt_size = caf->bytes_per_packet; yading@11: yading@11: if (pkt_size > 0 && pkt_frames == 1) { yading@11: pkt_size = (CAF_MAX_PKT_SIZE / pkt_size) * pkt_size; yading@11: pkt_size = FFMIN(pkt_size, left); yading@11: pkt_frames = pkt_size / caf->bytes_per_packet; yading@11: } else if (st->nb_index_entries) { yading@11: if (caf->packet_cnt < st->nb_index_entries - 1) { yading@11: pkt_size = st->index_entries[caf->packet_cnt + 1].pos - st->index_entries[caf->packet_cnt].pos; yading@11: pkt_frames = st->index_entries[caf->packet_cnt + 1].timestamp - st->index_entries[caf->packet_cnt].timestamp; yading@11: } else if (caf->packet_cnt == st->nb_index_entries - 1) { yading@11: pkt_size = caf->num_bytes - st->index_entries[caf->packet_cnt].pos; yading@11: pkt_frames = st->duration - st->index_entries[caf->packet_cnt].timestamp; yading@11: } else { yading@11: return AVERROR(EIO); yading@11: } yading@11: } yading@11: yading@11: if (pkt_size == 0 || pkt_frames == 0 || pkt_size > left) yading@11: return AVERROR(EIO); yading@11: yading@11: res = av_get_packet(pb, pkt, pkt_size); yading@11: if (res < 0) yading@11: return res; yading@11: yading@11: pkt->size = res; yading@11: pkt->stream_index = 0; yading@11: pkt->dts = pkt->pts = caf->frame_cnt; yading@11: yading@11: caf->packet_cnt++; yading@11: caf->frame_cnt += pkt_frames; yading@11: yading@11: return 0; yading@11: } yading@11: yading@11: static int read_seek(AVFormatContext *s, int stream_index, yading@11: int64_t timestamp, int flags) yading@11: { yading@11: AVStream *st = s->streams[0]; yading@11: CaffContext *caf = s->priv_data; yading@11: int64_t pos, packet_cnt, frame_cnt; yading@11: yading@11: timestamp = FFMAX(timestamp, 0); yading@11: yading@11: if (caf->frames_per_packet > 0 && caf->bytes_per_packet > 0) { yading@11: /* calculate new byte position based on target frame position */ yading@11: pos = caf->bytes_per_packet * (timestamp / caf->frames_per_packet); yading@11: if (caf->data_size > 0) yading@11: pos = FFMIN(pos, caf->data_size); yading@11: packet_cnt = pos / caf->bytes_per_packet; yading@11: frame_cnt = caf->frames_per_packet * packet_cnt; yading@11: } else if (st->nb_index_entries) { yading@11: packet_cnt = av_index_search_timestamp(st, timestamp, flags); yading@11: frame_cnt = st->index_entries[packet_cnt].timestamp; yading@11: pos = st->index_entries[packet_cnt].pos; yading@11: } else { yading@11: return -1; yading@11: } yading@11: yading@11: if (avio_seek(s->pb, pos + caf->data_start, SEEK_SET) < 0) yading@11: return -1; yading@11: yading@11: caf->packet_cnt = packet_cnt; yading@11: caf->frame_cnt = frame_cnt; yading@11: yading@11: return 0; yading@11: } yading@11: yading@11: AVInputFormat ff_caf_demuxer = { yading@11: .name = "caf", yading@11: .long_name = NULL_IF_CONFIG_SMALL("Apple CAF (Core Audio Format)"), yading@11: .priv_data_size = sizeof(CaffContext), yading@11: .read_probe = probe, yading@11: .read_header = read_header, yading@11: .read_packet = read_packet, yading@11: .read_seek = read_seek, yading@11: .codec_tag = (const AVCodecTag* const []){ ff_codec_caf_tags, 0 }, yading@11: };