1/* 2 * id Quake II CIN File Demuxer 3 * Copyright (c) 2003 The ffmpeg Project 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/** 23 * @file 24 * id Quake II CIN file demuxer by Mike Melanson (melanson@pcisys.net) 25 * For more information about the id CIN format, visit: 26 * http://www.csse.monash.edu.au/~timf/ 27 * 28 * CIN is a somewhat quirky and ill-defined format. Here are some notes 29 * for anyone trying to understand the technical details of this format: 30 * 31 * The format has no definite file signature. This is problematic for a 32 * general-purpose media player that wants to automatically detect file 33 * types. However, a CIN file does start with 5 32-bit numbers that 34 * specify audio and video parameters. This demuxer gets around the lack 35 * of file signature by performing sanity checks on those parameters. 36 * Probabalistically, this is a reasonable solution since the number of 37 * valid combinations of the 5 parameters is a very small subset of the 38 * total 160-bit number space. 39 * 40 * Refer to the function idcin_probe() for the precise A/V parameters 41 * that this demuxer allows. 42 * 43 * Next, each audio and video frame has a duration of 1/14 sec. If the 44 * audio sample rate is a multiple of the common frequency 22050 Hz it will 45 * divide evenly by 14. However, if the sample rate is 11025 Hz: 46 * 11025 (samples/sec) / 14 (frames/sec) = 787.5 (samples/frame) 47 * The way the CIN stores audio in this case is by storing 787 sample 48 * frames in the first audio frame and 788 sample frames in the second 49 * audio frame. Therefore, the total number of bytes in an audio frame 50 * is given as: 51 * audio frame #0: 787 * (bytes/sample) * (# channels) bytes in frame 52 * audio frame #1: 788 * (bytes/sample) * (# channels) bytes in frame 53 * audio frame #2: 787 * (bytes/sample) * (# channels) bytes in frame 54 * audio frame #3: 788 * (bytes/sample) * (# channels) bytes in frame 55 * 56 * Finally, not all id CIN creation tools agree on the resolution of the 57 * color palette, apparently. Some creation tools specify red, green, and 58 * blue palette components in terms of 6-bit VGA color DAC values which 59 * range from 0..63. Other tools specify the RGB components as full 8-bit 60 * values that range from 0..255. Since there are no markers in the file to 61 * differentiate between the two variants, this demuxer uses the following 62 * heuristic: 63 * - load the 768 palette bytes from disk 64 * - assume that they will need to be shifted left by 2 bits to 65 * transform them from 6-bit values to 8-bit values 66 * - scan through all 768 palette bytes 67 * - if any bytes exceed 63, do not shift the bytes at all before 68 * transmitting them to the video decoder 69 */ 70 71#include "libavutil/channel_layout.h" 72#include "libavutil/imgutils.h" 73#include "libavutil/intreadwrite.h" 74#include "avformat.h" 75#include "internal.h" 76 77#define HUFFMAN_TABLE_SIZE (64 * 1024) 78#define IDCIN_FPS 14 79 80typedef struct IdcinDemuxContext { 81 int video_stream_index; 82 int audio_stream_index; 83 int audio_chunk_size1; 84 int audio_chunk_size2; 85 int block_align; 86 87 /* demux state variables */ 88 int current_audio_chunk; 89 int next_chunk_is_video; 90 int audio_present; 91 int64_t first_pkt_pos; 92} IdcinDemuxContext; 93 94static int idcin_probe(AVProbeData *p) 95{ 96 unsigned int number, sample_rate; 97 unsigned int w, h; 98 int i; 99 100 /* 101 * This is what you could call a "probabilistic" file check: id CIN 102 * files don't have a definite file signature. In lieu of such a marker, 103 * perform sanity checks on the 5 32-bit header fields: 104 * width, height: greater than 0, less than or equal to 1024 105 * audio sample rate: greater than or equal to 8000, less than or 106 * equal to 48000, or 0 for no audio 107 * audio sample width (bytes/sample): 0 for no audio, or 1 or 2 108 * audio channels: 0 for no audio, or 1 or 2 109 */ 110 111 /* check we have enough data to do all checks, otherwise the 112 0-padding may cause a wrong recognition */ 113 if (p->buf_size < 20 + HUFFMAN_TABLE_SIZE + 12) 114 return 0; 115 116 /* check the video width */ 117 w = AV_RL32(&p->buf[0]); 118 if ((w == 0) || (w > 1024)) 119 return 0; 120 121 /* check the video height */ 122 h = AV_RL32(&p->buf[4]); 123 if ((h == 0) || (h > 1024)) 124 return 0; 125 126 /* check the audio sample rate */ 127 sample_rate = AV_RL32(&p->buf[8]); 128 if (sample_rate && (sample_rate < 8000 || sample_rate > 48000)) 129 return 0; 130 131 /* check the audio bytes/sample */ 132 number = AV_RL32(&p->buf[12]); 133 if (number > 2 || sample_rate && !number) 134 return 0; 135 136 /* check the audio channels */ 137 number = AV_RL32(&p->buf[16]); 138 if (number > 2 || sample_rate && !number) 139 return 0; 140 141 i = 20 + HUFFMAN_TABLE_SIZE; 142 if (AV_RL32(&p->buf[i]) == 1) 143 i += 768; 144 145 if (i+12 > p->buf_size || AV_RL32(&p->buf[i+8]) != w*h) 146 return 1; 147 148 /* return half certainty since this check is a bit sketchy */ 149 return AVPROBE_SCORE_EXTENSION; 150} 151 152static int idcin_read_header(AVFormatContext *s) 153{ 154 AVIOContext *pb = s->pb; 155 IdcinDemuxContext *idcin = s->priv_data; 156 AVStream *st; 157 unsigned int width, height; 158 unsigned int sample_rate, bytes_per_sample, channels; 159 int ret; 160 161 /* get the 5 header parameters */ 162 width = avio_rl32(pb); 163 height = avio_rl32(pb); 164 sample_rate = avio_rl32(pb); 165 bytes_per_sample = avio_rl32(pb); 166 channels = avio_rl32(pb); 167 168 if (s->pb->eof_reached) { 169 av_log(s, AV_LOG_ERROR, "incomplete header\n"); 170 return s->pb->error ? s->pb->error : AVERROR_EOF; 171 } 172 173 if (av_image_check_size(width, height, 0, s) < 0) 174 return AVERROR_INVALIDDATA; 175 if (sample_rate > 0) { 176 if (sample_rate < 14 || sample_rate > INT_MAX) { 177 av_log(s, AV_LOG_ERROR, "invalid sample rate: %u\n", sample_rate); 178 return AVERROR_INVALIDDATA; 179 } 180 if (bytes_per_sample < 1 || bytes_per_sample > 2) { 181 av_log(s, AV_LOG_ERROR, "invalid bytes per sample: %u\n", 182 bytes_per_sample); 183 return AVERROR_INVALIDDATA; 184 } 185 if (channels < 1 || channels > 2) { 186 av_log(s, AV_LOG_ERROR, "invalid channels: %u\n", channels); 187 return AVERROR_INVALIDDATA; 188 } 189 idcin->audio_present = 1; 190 } else { 191 /* if sample rate is 0, assume no audio */ 192 idcin->audio_present = 0; 193 } 194 195 st = avformat_new_stream(s, NULL); 196 if (!st) 197 return AVERROR(ENOMEM); 198 avpriv_set_pts_info(st, 33, 1, IDCIN_FPS); 199 st->start_time = 0; 200 idcin->video_stream_index = st->index; 201 st->codec->codec_type = AVMEDIA_TYPE_VIDEO; 202 st->codec->codec_id = AV_CODEC_ID_IDCIN; 203 st->codec->codec_tag = 0; /* no fourcc */ 204 st->codec->width = width; 205 st->codec->height = height; 206 207 /* load up the Huffman tables into extradata */ 208 if ((ret = ff_get_extradata(st->codec, pb, HUFFMAN_TABLE_SIZE)) < 0) 209 return ret; 210 211 if (idcin->audio_present) { 212 idcin->audio_present = 1; 213 st = avformat_new_stream(s, NULL); 214 if (!st) 215 return AVERROR(ENOMEM); 216 avpriv_set_pts_info(st, 63, 1, sample_rate); 217 st->start_time = 0; 218 idcin->audio_stream_index = st->index; 219 st->codec->codec_type = AVMEDIA_TYPE_AUDIO; 220 st->codec->codec_tag = 1; 221 st->codec->channels = channels; 222 st->codec->channel_layout = channels > 1 ? AV_CH_LAYOUT_STEREO : 223 AV_CH_LAYOUT_MONO; 224 st->codec->sample_rate = sample_rate; 225 st->codec->bits_per_coded_sample = bytes_per_sample * 8; 226 st->codec->bit_rate = sample_rate * bytes_per_sample * 8 * channels; 227 st->codec->block_align = idcin->block_align = bytes_per_sample * channels; 228 if (bytes_per_sample == 1) 229 st->codec->codec_id = AV_CODEC_ID_PCM_U8; 230 else 231 st->codec->codec_id = AV_CODEC_ID_PCM_S16LE; 232 233 if (sample_rate % 14 != 0) { 234 idcin->audio_chunk_size1 = (sample_rate / 14) * 235 bytes_per_sample * channels; 236 idcin->audio_chunk_size2 = (sample_rate / 14 + 1) * 237 bytes_per_sample * channels; 238 } else { 239 idcin->audio_chunk_size1 = idcin->audio_chunk_size2 = 240 (sample_rate / 14) * bytes_per_sample * channels; 241 } 242 idcin->current_audio_chunk = 0; 243 } 244 245 idcin->next_chunk_is_video = 1; 246 idcin->first_pkt_pos = avio_tell(s->pb); 247 248 return 0; 249} 250 251static int idcin_read_packet(AVFormatContext *s, 252 AVPacket *pkt) 253{ 254 int ret; 255 unsigned int command; 256 unsigned int chunk_size; 257 IdcinDemuxContext *idcin = s->priv_data; 258 AVIOContext *pb = s->pb; 259 int i; 260 int palette_scale; 261 unsigned char r, g, b; 262 unsigned char palette_buffer[768]; 263 uint32_t palette[256]; 264 265 if (url_feof(s->pb)) 266 return s->pb->error ? s->pb->error : AVERROR_EOF; 267 268 if (idcin->next_chunk_is_video) { 269 command = avio_rl32(pb); 270 if (command == 2) { 271 return AVERROR(EIO); 272 } else if (command == 1) { 273 /* trigger a palette change */ 274 ret = avio_read(pb, palette_buffer, 768); 275 if (ret < 0) { 276 return ret; 277 } else if (ret != 768) { 278 av_log(s, AV_LOG_ERROR, "incomplete packet\n"); 279 return AVERROR(EIO); 280 } 281 /* scale the palette as necessary */ 282 palette_scale = 2; 283 for (i = 0; i < 768; i++) 284 if (palette_buffer[i] > 63) { 285 palette_scale = 0; 286 break; 287 } 288 289 for (i = 0; i < 256; i++) { 290 r = palette_buffer[i * 3 ] << palette_scale; 291 g = palette_buffer[i * 3 + 1] << palette_scale; 292 b = palette_buffer[i * 3 + 2] << palette_scale; 293 palette[i] = (0xFFU << 24) | (r << 16) | (g << 8) | (b); 294 if (palette_scale == 2) 295 palette[i] |= palette[i] >> 6 & 0x30303; 296 } 297 } 298 299 if (s->pb->eof_reached) { 300 av_log(s, AV_LOG_ERROR, "incomplete packet\n"); 301 return s->pb->error ? s->pb->error : AVERROR_EOF; 302 } 303 chunk_size = avio_rl32(pb); 304 if (chunk_size < 4 || chunk_size > INT_MAX - 4) { 305 av_log(s, AV_LOG_ERROR, "invalid chunk size: %u\n", chunk_size); 306 return AVERROR_INVALIDDATA; 307 } 308 /* skip the number of decoded bytes (always equal to width * height) */ 309 avio_skip(pb, 4); 310 if (chunk_size < 4) 311 return AVERROR_INVALIDDATA; 312 chunk_size -= 4; 313 ret= av_get_packet(pb, pkt, chunk_size); 314 if (ret < 0) 315 return ret; 316 else if (ret != chunk_size) { 317 av_log(s, AV_LOG_ERROR, "incomplete packet\n"); 318 av_free_packet(pkt); 319 return AVERROR(EIO); 320 } 321 if (command == 1) { 322 uint8_t *pal; 323 324 pal = av_packet_new_side_data(pkt, AV_PKT_DATA_PALETTE, 325 AVPALETTE_SIZE); 326 if (!pal) { 327 av_free_packet(pkt); 328 return AVERROR(ENOMEM); 329 } 330 memcpy(pal, palette, AVPALETTE_SIZE); 331 pkt->flags |= AV_PKT_FLAG_KEY; 332 } 333 pkt->stream_index = idcin->video_stream_index; 334 pkt->duration = 1; 335 } else { 336 /* send out the audio chunk */ 337 if (idcin->current_audio_chunk) 338 chunk_size = idcin->audio_chunk_size2; 339 else 340 chunk_size = idcin->audio_chunk_size1; 341 ret= av_get_packet(pb, pkt, chunk_size); 342 if (ret < 0) 343 return ret; 344 pkt->stream_index = idcin->audio_stream_index; 345 pkt->duration = chunk_size / idcin->block_align; 346 347 idcin->current_audio_chunk ^= 1; 348 } 349 350 if (idcin->audio_present) 351 idcin->next_chunk_is_video ^= 1; 352 353 return 0; 354} 355 356static int idcin_read_seek(AVFormatContext *s, int stream_index, 357 int64_t timestamp, int flags) 358{ 359 IdcinDemuxContext *idcin = s->priv_data; 360 361 if (idcin->first_pkt_pos > 0) { 362 int ret = avio_seek(s->pb, idcin->first_pkt_pos, SEEK_SET); 363 if (ret < 0) 364 return ret; 365 ff_update_cur_dts(s, s->streams[idcin->video_stream_index], 0); 366 idcin->next_chunk_is_video = 1; 367 idcin->current_audio_chunk = 0; 368 return 0; 369 } 370 return -1; 371} 372 373AVInputFormat ff_idcin_demuxer = { 374 .name = "idcin", 375 .long_name = NULL_IF_CONFIG_SMALL("id Cinematic"), 376 .priv_data_size = sizeof(IdcinDemuxContext), 377 .read_probe = idcin_probe, 378 .read_header = idcin_read_header, 379 .read_packet = idcin_read_packet, 380 .read_seek = idcin_read_seek, 381 .flags = AVFMT_NO_BYTE_SEEK, 382}; 383