| /* |
| * Core Audio Format demuxer |
| * Copyright (c) 2007 Justin Ruggles |
| * Copyright (c) 2009 Peter Ross |
| * |
| * 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 |
| * Core Audio Format demuxer |
| */ |
| |
| #include "avformat.h" |
| #include "internal.h" |
| #include "riff.h" |
| #include "isom.h" |
| #include "libavutil/intreadwrite.h" |
| #include "libavutil/intfloat.h" |
| #include "libavutil/dict.h" |
| #include "caf.h" |
| |
| typedef struct { |
| int bytes_per_packet; ///< bytes in a packet, or 0 if variable |
| int frames_per_packet; ///< frames in a packet, or 0 if variable |
| int64_t num_bytes; ///< total number of bytes in stream |
| |
| int64_t packet_cnt; ///< packet counter |
| int64_t frame_cnt; ///< frame counter |
| |
| int64_t data_start; ///< data start position, in bytes |
| int64_t data_size; ///< raw data size, in bytes |
| } CaffContext; |
| |
| static int probe(AVProbeData *p) |
| { |
| if (AV_RB32(p->buf) == MKBETAG('c','a','f','f') && AV_RB16(&p->buf[4]) == 1) |
| return AVPROBE_SCORE_MAX; |
| return 0; |
| } |
| |
| /** Read audio description chunk */ |
| static int read_desc_chunk(AVFormatContext *s) |
| { |
| AVIOContext *pb = s->pb; |
| CaffContext *caf = s->priv_data; |
| AVStream *st; |
| int flags; |
| |
| /* new audio stream */ |
| st = avformat_new_stream(s, NULL); |
| if (!st) |
| return AVERROR(ENOMEM); |
| |
| /* parse format description */ |
| st->codec->codec_type = AVMEDIA_TYPE_AUDIO; |
| st->codec->sample_rate = av_int2double(avio_rb64(pb)); |
| st->codec->codec_tag = avio_rl32(pb); |
| flags = avio_rb32(pb); |
| caf->bytes_per_packet = avio_rb32(pb); |
| st->codec->block_align = caf->bytes_per_packet; |
| caf->frames_per_packet = avio_rb32(pb); |
| st->codec->channels = avio_rb32(pb); |
| st->codec->bits_per_coded_sample = avio_rb32(pb); |
| |
| /* calculate bit rate for constant size packets */ |
| if (caf->frames_per_packet > 0 && caf->bytes_per_packet > 0) { |
| st->codec->bit_rate = (uint64_t)st->codec->sample_rate * (uint64_t)caf->bytes_per_packet * 8 |
| / (uint64_t)caf->frames_per_packet; |
| } else { |
| st->codec->bit_rate = 0; |
| } |
| |
| /* determine codec */ |
| if (st->codec->codec_tag == MKTAG('l','p','c','m')) |
| st->codec->codec_id = ff_mov_get_lpcm_codec_id(st->codec->bits_per_coded_sample, (flags ^ 0x2) | 0x4); |
| else |
| st->codec->codec_id = ff_codec_get_id(ff_codec_caf_tags, st->codec->codec_tag); |
| return 0; |
| } |
| |
| /** Read magic cookie chunk */ |
| static int read_kuki_chunk(AVFormatContext *s, int64_t size) |
| { |
| AVIOContext *pb = s->pb; |
| AVStream *st = s->streams[0]; |
| |
| if (size < 0 || size > INT_MAX - FF_INPUT_BUFFER_PADDING_SIZE) |
| return -1; |
| |
| if (st->codec->codec_id == CODEC_ID_AAC) { |
| /* The magic cookie format for AAC is an mp4 esds atom. |
| The lavc AAC decoder requires the data from the codec specific |
| description as extradata input. */ |
| int strt, skip; |
| MOVAtom atom; |
| |
| strt = avio_tell(pb); |
| ff_mov_read_esds(s, pb, atom); |
| skip = size - (avio_tell(pb) - strt); |
| if (skip < 0 || !st->codec->extradata || |
| st->codec->codec_id != CODEC_ID_AAC) { |
| av_log(s, AV_LOG_ERROR, "invalid AAC magic cookie\n"); |
| return AVERROR_INVALIDDATA; |
| } |
| avio_skip(pb, skip); |
| } else if (st->codec->codec_id == CODEC_ID_ALAC) { |
| #define ALAC_PREAMBLE 12 |
| #define ALAC_HEADER 36 |
| #define ALAC_NEW_KUKI 24 |
| if (size == ALAC_NEW_KUKI) { |
| st->codec->extradata = av_mallocz(ALAC_HEADER + FF_INPUT_BUFFER_PADDING_SIZE); |
| if (!st->codec->extradata) |
| return AVERROR(ENOMEM); |
| memcpy(st->codec->extradata, "\0\0\0\24alac", 8); |
| avio_read(pb, st->codec->extradata + ALAC_HEADER - ALAC_NEW_KUKI, ALAC_NEW_KUKI); |
| st->codec->extradata_size = ALAC_HEADER; |
| } else { |
| if (size < ALAC_PREAMBLE + ALAC_HEADER) { |
| av_log(s, AV_LOG_ERROR, "invalid ALAC magic cookie\n"); |
| avio_skip(pb, size); |
| return AVERROR_INVALIDDATA; |
| } |
| avio_skip(pb, ALAC_PREAMBLE); |
| st->codec->extradata = av_mallocz(ALAC_HEADER + FF_INPUT_BUFFER_PADDING_SIZE); |
| if (!st->codec->extradata) |
| return AVERROR(ENOMEM); |
| avio_read(pb, st->codec->extradata, ALAC_HEADER); |
| st->codec->extradata_size = ALAC_HEADER; |
| avio_skip(pb, size - ALAC_PREAMBLE - ALAC_HEADER); |
| } |
| } else { |
| st->codec->extradata = av_mallocz(size + FF_INPUT_BUFFER_PADDING_SIZE); |
| if (!st->codec->extradata) |
| return AVERROR(ENOMEM); |
| avio_read(pb, st->codec->extradata, size); |
| st->codec->extradata_size = size; |
| } |
| |
| return 0; |
| } |
| |
| /** Read packet table chunk */ |
| static int read_pakt_chunk(AVFormatContext *s, int64_t size) |
| { |
| AVIOContext *pb = s->pb; |
| AVStream *st = s->streams[0]; |
| CaffContext *caf = s->priv_data; |
| int64_t pos = 0, ccount; |
| int num_packets, i; |
| |
| ccount = avio_tell(pb); |
| |
| num_packets = avio_rb64(pb); |
| if (num_packets < 0 || INT32_MAX / sizeof(AVIndexEntry) < num_packets) |
| return AVERROR_INVALIDDATA; |
| |
| st->nb_frames = avio_rb64(pb); /* valid frames */ |
| st->nb_frames += avio_rb32(pb); /* priming frames */ |
| st->nb_frames += avio_rb32(pb); /* remainder frames */ |
| |
| st->duration = 0; |
| for (i = 0; i < num_packets; i++) { |
| av_add_index_entry(s->streams[0], pos, st->duration, 0, 0, AVINDEX_KEYFRAME); |
| pos += caf->bytes_per_packet ? caf->bytes_per_packet : ff_mp4_read_descr_len(pb); |
| st->duration += caf->frames_per_packet ? caf->frames_per_packet : ff_mp4_read_descr_len(pb); |
| } |
| |
| if (avio_tell(pb) - ccount != size) { |
| av_log(s, AV_LOG_ERROR, "error reading packet table\n"); |
| return -1; |
| } |
| |
| caf->num_bytes = pos; |
| return 0; |
| } |
| |
| /** Read information chunk */ |
| static void read_info_chunk(AVFormatContext *s, int64_t size) |
| { |
| AVIOContext *pb = s->pb; |
| unsigned int i; |
| unsigned int nb_entries = avio_rb32(pb); |
| for (i = 0; i < nb_entries; i++) { |
| char key[32]; |
| char value[1024]; |
| avio_get_str(pb, INT_MAX, key, sizeof(key)); |
| avio_get_str(pb, INT_MAX, value, sizeof(value)); |
| av_dict_set(&s->metadata, key, value, 0); |
| } |
| } |
| |
| static int read_header(AVFormatContext *s) |
| { |
| AVIOContext *pb = s->pb; |
| CaffContext *caf = s->priv_data; |
| AVStream *st; |
| uint32_t tag = 0; |
| int found_data, ret; |
| int64_t size; |
| |
| avio_skip(pb, 8); /* magic, version, file flags */ |
| |
| /* audio description chunk */ |
| if (avio_rb32(pb) != MKBETAG('d','e','s','c')) { |
| av_log(s, AV_LOG_ERROR, "desc chunk not present\n"); |
| return AVERROR_INVALIDDATA; |
| } |
| size = avio_rb64(pb); |
| if (size != 32) |
| return AVERROR_INVALIDDATA; |
| |
| ret = read_desc_chunk(s); |
| if (ret) |
| return ret; |
| st = s->streams[0]; |
| |
| /* parse each chunk */ |
| found_data = 0; |
| while (!url_feof(pb)) { |
| |
| /* stop at data chunk if seeking is not supported or |
| data chunk size is unknown */ |
| if (found_data && (caf->data_size < 0 || !pb->seekable)) |
| break; |
| |
| tag = avio_rb32(pb); |
| size = avio_rb64(pb); |
| if (url_feof(pb)) |
| break; |
| |
| switch (tag) { |
| case MKBETAG('d','a','t','a'): |
| avio_skip(pb, 4); /* edit count */ |
| caf->data_start = avio_tell(pb); |
| caf->data_size = size < 0 ? -1 : size - 4; |
| if (caf->data_size > 0 && pb->seekable) |
| avio_skip(pb, caf->data_size); |
| found_data = 1; |
| break; |
| |
| /* magic cookie chunk */ |
| case MKBETAG('k','u','k','i'): |
| if (read_kuki_chunk(s, size)) |
| return AVERROR_INVALIDDATA; |
| break; |
| |
| /* packet table chunk */ |
| case MKBETAG('p','a','k','t'): |
| if (read_pakt_chunk(s, size)) |
| return AVERROR_INVALIDDATA; |
| break; |
| |
| case MKBETAG('i','n','f','o'): |
| read_info_chunk(s, size); |
| break; |
| |
| case MKBETAG('c','h','a','n'): |
| if (size < 12) |
| return AVERROR_INVALIDDATA; |
| ff_mov_read_chan(s, size, st->codec); |
| break; |
| |
| default: |
| #define _(x) ((x) >= ' ' ? (x) : ' ') |
| av_log(s, AV_LOG_WARNING, "skipping CAF chunk: %08X (%c%c%c%c), size %"PRId64"\n", |
| tag, _(tag>>24), _((tag>>16)&0xFF), _((tag>>8)&0xFF), _(tag&0xFF), size); |
| #undef _ |
| case MKBETAG('f','r','e','e'): |
| if (size < 0) |
| return AVERROR_INVALIDDATA; |
| avio_skip(pb, size); |
| break; |
| } |
| } |
| |
| if (!found_data) |
| return AVERROR_INVALIDDATA; |
| |
| if (caf->bytes_per_packet > 0 && caf->frames_per_packet > 0) { |
| if (caf->data_size > 0) |
| st->nb_frames = (caf->data_size / caf->bytes_per_packet) * caf->frames_per_packet; |
| } else if (st->nb_index_entries) { |
| st->codec->bit_rate = st->codec->sample_rate * caf->data_size * 8 / |
| st->duration; |
| } else { |
| av_log(s, AV_LOG_ERROR, "Missing packet table. It is required when " |
| "block size or frame size are variable.\n"); |
| return AVERROR_INVALIDDATA; |
| } |
| |
| avpriv_set_pts_info(st, 64, 1, st->codec->sample_rate); |
| st->start_time = 0; |
| |
| /* position the stream at the start of data */ |
| if (caf->data_size >= 0) |
| avio_seek(pb, caf->data_start, SEEK_SET); |
| |
| return 0; |
| } |
| |
| #define CAF_MAX_PKT_SIZE 4096 |
| |
| static int read_packet(AVFormatContext *s, AVPacket *pkt) |
| { |
| AVIOContext *pb = s->pb; |
| AVStream *st = s->streams[0]; |
| CaffContext *caf = s->priv_data; |
| int res, pkt_size = 0, pkt_frames = 0; |
| int64_t left = CAF_MAX_PKT_SIZE; |
| |
| if (url_feof(pb)) |
| return AVERROR(EIO); |
| |
| /* don't read past end of data chunk */ |
| if (caf->data_size > 0) { |
| left = (caf->data_start + caf->data_size) - avio_tell(pb); |
| if (left <= 0) |
| return AVERROR(EIO); |
| } |
| |
| pkt_frames = caf->frames_per_packet; |
| pkt_size = caf->bytes_per_packet; |
| |
| if (pkt_size > 0 && pkt_frames == 1) { |
| pkt_size = (CAF_MAX_PKT_SIZE / pkt_size) * pkt_size; |
| pkt_size = FFMIN(pkt_size, left); |
| pkt_frames = pkt_size / caf->bytes_per_packet; |
| } else if (st->nb_index_entries) { |
| if (caf->packet_cnt < st->nb_index_entries - 1) { |
| pkt_size = st->index_entries[caf->packet_cnt + 1].pos - st->index_entries[caf->packet_cnt].pos; |
| pkt_frames = st->index_entries[caf->packet_cnt + 1].timestamp - st->index_entries[caf->packet_cnt].timestamp; |
| } else if (caf->packet_cnt == st->nb_index_entries - 1) { |
| pkt_size = caf->num_bytes - st->index_entries[caf->packet_cnt].pos; |
| pkt_frames = st->duration - st->index_entries[caf->packet_cnt].timestamp; |
| } else { |
| return AVERROR(EIO); |
| } |
| } |
| |
| if (pkt_size == 0 || pkt_frames == 0 || pkt_size > left) |
| return AVERROR(EIO); |
| |
| res = av_get_packet(pb, pkt, pkt_size); |
| if (res < 0) |
| return res; |
| |
| pkt->size = res; |
| pkt->stream_index = 0; |
| pkt->dts = pkt->pts = caf->frame_cnt; |
| |
| caf->packet_cnt++; |
| caf->frame_cnt += pkt_frames; |
| |
| return 0; |
| } |
| |
| static int read_seek(AVFormatContext *s, int stream_index, |
| int64_t timestamp, int flags) |
| { |
| AVStream *st = s->streams[0]; |
| CaffContext *caf = s->priv_data; |
| int64_t pos, packet_cnt, frame_cnt; |
| |
| timestamp = FFMAX(timestamp, 0); |
| |
| if (caf->frames_per_packet > 0 && caf->bytes_per_packet > 0) { |
| /* calculate new byte position based on target frame position */ |
| pos = caf->bytes_per_packet * timestamp / caf->frames_per_packet; |
| if (caf->data_size > 0) |
| pos = FFMIN(pos, caf->data_size); |
| packet_cnt = pos / caf->bytes_per_packet; |
| frame_cnt = caf->frames_per_packet * packet_cnt; |
| } else if (st->nb_index_entries) { |
| packet_cnt = av_index_search_timestamp(st, timestamp, flags); |
| frame_cnt = st->index_entries[packet_cnt].timestamp; |
| pos = st->index_entries[packet_cnt].pos; |
| } else { |
| return -1; |
| } |
| |
| if (avio_seek(s->pb, pos + caf->data_start, SEEK_SET) < 0) |
| return -1; |
| |
| caf->packet_cnt = packet_cnt; |
| caf->frame_cnt = frame_cnt; |
| |
| return 0; |
| } |
| |
| AVInputFormat ff_caf_demuxer = { |
| .name = "caf", |
| .long_name = NULL_IF_CONFIG_SMALL("Apple Core Audio Format"), |
| .priv_data_size = sizeof(CaffContext), |
| .read_probe = probe, |
| .read_header = read_header, |
| .read_packet = read_packet, |
| .read_seek = read_seek, |
| .codec_tag = (const AVCodecTag*[]){ ff_codec_caf_tags, 0 }, |
| }; |