1/* 2 * CDXL demuxer 3 * Copyright (c) 2011-2012 Paul B Mahol 4 * 5 * This file is part of FFmpeg. 6 * 7 * FFmpeg is free software; you can redistribute it and/or 8 * modify it under the terms of the GNU Lesser General Public 9 * License as published by the Free Software Foundation; either 10 * version 2.1 of the License, or (at your option) any later version. 11 * 12 * FFmpeg is distributed in the hope that it will be useful, 13 * but WITHOUT ANY WARRANTY; without even the implied warranty of 14 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU 15 * Lesser General Public License for more details. 16 * 17 * You should have received a copy of the GNU Lesser General Public 18 * License along with FFmpeg; if not, write to the Free Software 19 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA 20 */ 21 22#include "libavutil/channel_layout.h" 23#include "libavutil/intreadwrite.h" 24#include "libavutil/parseutils.h" 25#include "libavutil/opt.h" 26#include "avformat.h" 27#include "internal.h" 28 29#define CDXL_HEADER_SIZE 32 30 31typedef struct CDXLDemuxContext { 32 AVClass *class; 33 int sample_rate; 34 char *framerate; 35 AVRational fps; 36 int read_chunk; 37 uint8_t header[CDXL_HEADER_SIZE]; 38 int video_stream_index; 39 int audio_stream_index; 40} CDXLDemuxContext; 41 42static int cdxl_read_probe(AVProbeData *p) 43{ 44 int score = AVPROBE_SCORE_EXTENSION + 10; 45 46 if (p->buf_size < CDXL_HEADER_SIZE) 47 return 0; 48 49 /* reserved bytes should always be set to 0 */ 50 if (AV_RN64(&p->buf[24]) || AV_RN16(&p->buf[10])) 51 return 0; 52 53 /* check type */ 54 if (p->buf[0] != 1) 55 return 0; 56 57 /* check palette size */ 58 if (AV_RB16(&p->buf[20]) > 512) 59 return 0; 60 61 /* check number of planes */ 62 if (p->buf[18] || !p->buf[19]) 63 return 0; 64 65 /* check widh and height */ 66 if (!AV_RN16(&p->buf[14]) || !AV_RN16(&p->buf[16])) 67 return 0; 68 69 /* chunk size */ 70 if (AV_RB32(&p->buf[2]) < AV_RB16(&p->buf[22]) + AV_RB16(&p->buf[20]) + CDXL_HEADER_SIZE) 71 return 0; 72 73 /* previous chunk size */ 74 if (AV_RN32(&p->buf[6])) 75 score /= 2; 76 77 /* current frame number, usually starts from 1 */ 78 if (AV_RB16(&p->buf[12]) != 1) 79 score /= 2; 80 81 return score; 82} 83 84static int cdxl_read_header(AVFormatContext *s) 85{ 86 CDXLDemuxContext *cdxl = s->priv_data; 87 int ret; 88 89 if (cdxl->framerate && (ret = av_parse_video_rate(&cdxl->fps, cdxl->framerate)) < 0) { 90 av_log(s, AV_LOG_ERROR, 91 "Could not parse framerate: %s.\n", cdxl->framerate); 92 return ret; 93 } 94 95 cdxl->read_chunk = 0; 96 cdxl->video_stream_index = -1; 97 cdxl->audio_stream_index = -1; 98 99 s->ctx_flags |= AVFMTCTX_NOHEADER; 100 101 return 0; 102} 103 104static int cdxl_read_packet(AVFormatContext *s, AVPacket *pkt) 105{ 106 CDXLDemuxContext *cdxl = s->priv_data; 107 AVIOContext *pb = s->pb; 108 uint32_t current_size, video_size, image_size; 109 uint16_t audio_size, palette_size, width, height; 110 int64_t pos; 111 int ret; 112 113 if (url_feof(pb)) 114 return AVERROR_EOF; 115 116 pos = avio_tell(pb); 117 if (!cdxl->read_chunk && 118 avio_read(pb, cdxl->header, CDXL_HEADER_SIZE) != CDXL_HEADER_SIZE) 119 return AVERROR_EOF; 120 if (cdxl->header[0] != 1) { 121 av_log(s, AV_LOG_ERROR, "non-standard cdxl file\n"); 122 return AVERROR_INVALIDDATA; 123 } 124 125 current_size = AV_RB32(&cdxl->header[2]); 126 width = AV_RB16(&cdxl->header[14]); 127 height = AV_RB16(&cdxl->header[16]); 128 palette_size = AV_RB16(&cdxl->header[20]); 129 audio_size = AV_RB16(&cdxl->header[22]); 130 image_size = FFALIGN(width, 16) * height * cdxl->header[19] / 8; 131 video_size = palette_size + image_size; 132 133 if (palette_size > 512) 134 return AVERROR_INVALIDDATA; 135 if (current_size < (uint64_t)audio_size + video_size + CDXL_HEADER_SIZE) 136 return AVERROR_INVALIDDATA; 137 138 if (cdxl->read_chunk && audio_size) { 139 if (cdxl->audio_stream_index == -1) { 140 AVStream *st = avformat_new_stream(s, NULL); 141 if (!st) 142 return AVERROR(ENOMEM); 143 144 st->codec->codec_type = AVMEDIA_TYPE_AUDIO; 145 st->codec->codec_tag = 0; 146 st->codec->codec_id = AV_CODEC_ID_PCM_S8; 147 if (cdxl->header[1] & 0x10) { 148 st->codec->channels = 2; 149 st->codec->channel_layout = AV_CH_LAYOUT_STEREO; 150 } else { 151 st->codec->channels = 1; 152 st->codec->channel_layout = AV_CH_LAYOUT_MONO; 153 } 154 st->codec->sample_rate = cdxl->sample_rate; 155 st->start_time = 0; 156 cdxl->audio_stream_index = st->index; 157 avpriv_set_pts_info(st, 64, 1, cdxl->sample_rate); 158 } 159 160 ret = av_get_packet(pb, pkt, audio_size); 161 if (ret < 0) 162 return ret; 163 pkt->stream_index = cdxl->audio_stream_index; 164 pkt->pos = pos; 165 pkt->duration = audio_size; 166 cdxl->read_chunk = 0; 167 } else { 168 if (cdxl->video_stream_index == -1) { 169 AVStream *st = avformat_new_stream(s, NULL); 170 if (!st) 171 return AVERROR(ENOMEM); 172 173 st->codec->codec_type = AVMEDIA_TYPE_VIDEO; 174 st->codec->codec_tag = 0; 175 st->codec->codec_id = AV_CODEC_ID_CDXL; 176 st->codec->width = width; 177 st->codec->height = height; 178 st->start_time = 0; 179 cdxl->video_stream_index = st->index; 180 if (cdxl->framerate) 181 avpriv_set_pts_info(st, 64, cdxl->fps.den, cdxl->fps.num); 182 else 183 avpriv_set_pts_info(st, 64, 1, cdxl->sample_rate); 184 } 185 186 if (av_new_packet(pkt, video_size + CDXL_HEADER_SIZE) < 0) 187 return AVERROR(ENOMEM); 188 memcpy(pkt->data, cdxl->header, CDXL_HEADER_SIZE); 189 ret = avio_read(pb, pkt->data + CDXL_HEADER_SIZE, video_size); 190 if (ret < 0) { 191 av_free_packet(pkt); 192 return ret; 193 } 194 av_shrink_packet(pkt, CDXL_HEADER_SIZE + ret); 195 pkt->stream_index = cdxl->video_stream_index; 196 pkt->flags |= AV_PKT_FLAG_KEY; 197 pkt->pos = pos; 198 pkt->duration = cdxl->framerate ? 1 : audio_size ? audio_size : 220; 199 cdxl->read_chunk = audio_size; 200 } 201 202 if (!cdxl->read_chunk) 203 avio_skip(pb, current_size - audio_size - video_size - CDXL_HEADER_SIZE); 204 return ret; 205} 206 207#define OFFSET(x) offsetof(CDXLDemuxContext, x) 208static const AVOption cdxl_options[] = { 209 { "sample_rate", "", OFFSET(sample_rate), AV_OPT_TYPE_INT, { .i64 = 11025 }, 1, INT_MAX, AV_OPT_FLAG_DECODING_PARAM }, 210 { "framerate", "", OFFSET(framerate), AV_OPT_TYPE_STRING, { .str = NULL }, 0, 0, AV_OPT_FLAG_DECODING_PARAM }, 211 { NULL }, 212}; 213 214static const AVClass cdxl_demuxer_class = { 215 .class_name = "CDXL demuxer", 216 .item_name = av_default_item_name, 217 .option = cdxl_options, 218 .version = LIBAVUTIL_VERSION_INT, 219}; 220 221AVInputFormat ff_cdxl_demuxer = { 222 .name = "cdxl", 223 .long_name = NULL_IF_CONFIG_SMALL("Commodore CDXL video"), 224 .priv_data_size = sizeof(CDXLDemuxContext), 225 .read_probe = cdxl_read_probe, 226 .read_header = cdxl_read_header, 227 .read_packet = cdxl_read_packet, 228 .extensions = "cdxl,xl", 229 .flags = AVFMT_GENERIC_INDEX, 230 .priv_class = &cdxl_demuxer_class, 231}; 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