| 1 | /* |
| 2 | * RL2 Format Demuxer |
| 3 | * Copyright (c) 2008 Sascha Sommer (saschasommer@freenet.de) |
| 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 | * RL2 file demuxer |
| 24 | * @file |
| 25 | * @author Sascha Sommer (saschasommer@freenet.de) |
| 26 | * @see http://wiki.multimedia.cx/index.php?title=RL2 |
| 27 | * |
| 28 | * extradata: |
| 29 | * 2 byte le initial drawing offset within 320x200 viewport |
| 30 | * 4 byte le number of used colors |
| 31 | * 256 * 3 bytes rgb palette |
| 32 | * optional background_frame |
| 33 | */ |
| 34 | |
| 35 | #include <stdint.h> |
| 36 | |
| 37 | #include "libavutil/intreadwrite.h" |
| 38 | #include "libavutil/mathematics.h" |
| 39 | #include "avformat.h" |
| 40 | #include "internal.h" |
| 41 | |
| 42 | #define EXTRADATA1_SIZE (6 + 256 * 3) ///< video base, clr, palette |
| 43 | |
| 44 | #define FORM_TAG MKBETAG('F', 'O', 'R', 'M') |
| 45 | #define RLV2_TAG MKBETAG('R', 'L', 'V', '2') |
| 46 | #define RLV3_TAG MKBETAG('R', 'L', 'V', '3') |
| 47 | |
| 48 | typedef struct Rl2DemuxContext { |
| 49 | unsigned int index_pos[2]; ///< indexes in the sample tables |
| 50 | } Rl2DemuxContext; |
| 51 | |
| 52 | |
| 53 | /** |
| 54 | * check if the file is in rl2 format |
| 55 | * @param p probe buffer |
| 56 | * @return 0 when the probe buffer does not contain rl2 data, > 0 otherwise |
| 57 | */ |
| 58 | static int rl2_probe(AVProbeData *p) |
| 59 | { |
| 60 | |
| 61 | if(AV_RB32(&p->buf[0]) != FORM_TAG) |
| 62 | return 0; |
| 63 | |
| 64 | if(AV_RB32(&p->buf[8]) != RLV2_TAG && |
| 65 | AV_RB32(&p->buf[8]) != RLV3_TAG) |
| 66 | return 0; |
| 67 | |
| 68 | return AVPROBE_SCORE_MAX; |
| 69 | } |
| 70 | |
| 71 | /** |
| 72 | * read rl2 header data and setup the avstreams |
| 73 | * @param s demuxer context |
| 74 | * @return 0 on success, AVERROR otherwise |
| 75 | */ |
| 76 | static av_cold int rl2_read_header(AVFormatContext *s) |
| 77 | { |
| 78 | AVIOContext *pb = s->pb; |
| 79 | AVStream *st; |
| 80 | unsigned int frame_count; |
| 81 | unsigned int audio_frame_counter = 0; |
| 82 | unsigned int video_frame_counter = 0; |
| 83 | unsigned int back_size; |
| 84 | unsigned short sound_rate; |
| 85 | unsigned short rate; |
| 86 | unsigned short channels; |
| 87 | unsigned short def_sound_size; |
| 88 | unsigned int signature; |
| 89 | unsigned int pts_den = 11025; /* video only case */ |
| 90 | unsigned int pts_num = 1103; |
| 91 | unsigned int* chunk_offset = NULL; |
| 92 | int* chunk_size = NULL; |
| 93 | int* audio_size = NULL; |
| 94 | int i; |
| 95 | int ret = 0; |
| 96 | |
| 97 | avio_skip(pb,4); /* skip FORM tag */ |
| 98 | back_size = avio_rl32(pb); /**< get size of the background frame */ |
| 99 | signature = avio_rb32(pb); |
| 100 | avio_skip(pb, 4); /* data size */ |
| 101 | frame_count = avio_rl32(pb); |
| 102 | |
| 103 | /* disallow back_sizes and frame_counts that may lead to overflows later */ |
| 104 | if(back_size > INT_MAX/2 || frame_count > INT_MAX / sizeof(uint32_t)) |
| 105 | return AVERROR_INVALIDDATA; |
| 106 | |
| 107 | avio_skip(pb, 2); /* encoding mentod */ |
| 108 | sound_rate = avio_rl16(pb); |
| 109 | rate = avio_rl16(pb); |
| 110 | channels = avio_rl16(pb); |
| 111 | def_sound_size = avio_rl16(pb); |
| 112 | |
| 113 | /** setup video stream */ |
| 114 | st = avformat_new_stream(s, NULL); |
| 115 | if(!st) |
| 116 | return AVERROR(ENOMEM); |
| 117 | |
| 118 | st->codec->codec_type = AVMEDIA_TYPE_VIDEO; |
| 119 | st->codec->codec_id = AV_CODEC_ID_RL2; |
| 120 | st->codec->codec_tag = 0; /* no fourcc */ |
| 121 | st->codec->width = 320; |
| 122 | st->codec->height = 200; |
| 123 | |
| 124 | /** allocate and fill extradata */ |
| 125 | st->codec->extradata_size = EXTRADATA1_SIZE; |
| 126 | |
| 127 | if(signature == RLV3_TAG && back_size > 0) |
| 128 | st->codec->extradata_size += back_size; |
| 129 | |
| 130 | if(ff_get_extradata(st->codec, pb, st->codec->extradata_size) < 0) |
| 131 | return AVERROR(ENOMEM); |
| 132 | |
| 133 | /** setup audio stream if present */ |
| 134 | if(sound_rate){ |
| 135 | if (!channels || channels > 42) { |
| 136 | av_log(s, AV_LOG_ERROR, "Invalid number of channels: %d\n", channels); |
| 137 | return AVERROR_INVALIDDATA; |
| 138 | } |
| 139 | |
| 140 | pts_num = def_sound_size; |
| 141 | pts_den = rate; |
| 142 | |
| 143 | st = avformat_new_stream(s, NULL); |
| 144 | if (!st) |
| 145 | return AVERROR(ENOMEM); |
| 146 | st->codec->codec_type = AVMEDIA_TYPE_AUDIO; |
| 147 | st->codec->codec_id = AV_CODEC_ID_PCM_U8; |
| 148 | st->codec->codec_tag = 1; |
| 149 | st->codec->channels = channels; |
| 150 | st->codec->bits_per_coded_sample = 8; |
| 151 | st->codec->sample_rate = rate; |
| 152 | st->codec->bit_rate = st->codec->channels * st->codec->sample_rate * |
| 153 | st->codec->bits_per_coded_sample; |
| 154 | st->codec->block_align = st->codec->channels * |
| 155 | st->codec->bits_per_coded_sample / 8; |
| 156 | avpriv_set_pts_info(st,32,1,rate); |
| 157 | } |
| 158 | |
| 159 | avpriv_set_pts_info(s->streams[0], 32, pts_num, pts_den); |
| 160 | |
| 161 | chunk_size = av_malloc(frame_count * sizeof(uint32_t)); |
| 162 | audio_size = av_malloc(frame_count * sizeof(uint32_t)); |
| 163 | chunk_offset = av_malloc(frame_count * sizeof(uint32_t)); |
| 164 | |
| 165 | if(!chunk_size || !audio_size || !chunk_offset){ |
| 166 | av_free(chunk_size); |
| 167 | av_free(audio_size); |
| 168 | av_free(chunk_offset); |
| 169 | return AVERROR(ENOMEM); |
| 170 | } |
| 171 | |
| 172 | /** read offset and size tables */ |
| 173 | for(i=0; i < frame_count;i++) |
| 174 | chunk_size[i] = avio_rl32(pb); |
| 175 | for(i=0; i < frame_count;i++) |
| 176 | chunk_offset[i] = avio_rl32(pb); |
| 177 | for(i=0; i < frame_count;i++) |
| 178 | audio_size[i] = avio_rl32(pb) & 0xFFFF; |
| 179 | |
| 180 | /** build the sample index */ |
| 181 | for(i=0;i<frame_count;i++){ |
| 182 | if(chunk_size[i] < 0 || audio_size[i] > chunk_size[i]){ |
| 183 | ret = AVERROR_INVALIDDATA; |
| 184 | break; |
| 185 | } |
| 186 | |
| 187 | if(sound_rate && audio_size[i]){ |
| 188 | av_add_index_entry(s->streams[1], chunk_offset[i], |
| 189 | audio_frame_counter,audio_size[i], 0, AVINDEX_KEYFRAME); |
| 190 | audio_frame_counter += audio_size[i] / channels; |
| 191 | } |
| 192 | av_add_index_entry(s->streams[0], chunk_offset[i] + audio_size[i], |
| 193 | video_frame_counter,chunk_size[i]-audio_size[i],0,AVINDEX_KEYFRAME); |
| 194 | ++video_frame_counter; |
| 195 | } |
| 196 | |
| 197 | |
| 198 | av_free(chunk_size); |
| 199 | av_free(audio_size); |
| 200 | av_free(chunk_offset); |
| 201 | |
| 202 | return ret; |
| 203 | } |
| 204 | |
| 205 | /** |
| 206 | * read a single audio or video packet |
| 207 | * @param s demuxer context |
| 208 | * @param pkt the packet to be filled |
| 209 | * @return 0 on success, AVERROR otherwise |
| 210 | */ |
| 211 | static int rl2_read_packet(AVFormatContext *s, |
| 212 | AVPacket *pkt) |
| 213 | { |
| 214 | Rl2DemuxContext *rl2 = s->priv_data; |
| 215 | AVIOContext *pb = s->pb; |
| 216 | AVIndexEntry *sample = NULL; |
| 217 | int i; |
| 218 | int ret = 0; |
| 219 | int stream_id = -1; |
| 220 | int64_t pos = INT64_MAX; |
| 221 | |
| 222 | /** check if there is a valid video or audio entry that can be used */ |
| 223 | for(i=0; i<s->nb_streams; i++){ |
| 224 | if(rl2->index_pos[i] < s->streams[i]->nb_index_entries |
| 225 | && s->streams[i]->index_entries[ rl2->index_pos[i] ].pos < pos){ |
| 226 | sample = &s->streams[i]->index_entries[ rl2->index_pos[i] ]; |
| 227 | pos= sample->pos; |
| 228 | stream_id= i; |
| 229 | } |
| 230 | } |
| 231 | |
| 232 | if(stream_id == -1) |
| 233 | return AVERROR_EOF; |
| 234 | |
| 235 | ++rl2->index_pos[stream_id]; |
| 236 | |
| 237 | /** position the stream (will probably be there anyway) */ |
| 238 | avio_seek(pb, sample->pos, SEEK_SET); |
| 239 | |
| 240 | /** fill the packet */ |
| 241 | ret = av_get_packet(pb, pkt, sample->size); |
| 242 | if(ret != sample->size){ |
| 243 | av_free_packet(pkt); |
| 244 | return AVERROR(EIO); |
| 245 | } |
| 246 | |
| 247 | pkt->stream_index = stream_id; |
| 248 | pkt->pts = sample->timestamp; |
| 249 | |
| 250 | return ret; |
| 251 | } |
| 252 | |
| 253 | /** |
| 254 | * seek to a new timestamp |
| 255 | * @param s demuxer context |
| 256 | * @param stream_index index of the stream that should be seeked |
| 257 | * @param timestamp wanted timestamp |
| 258 | * @param flags direction and seeking mode |
| 259 | * @return 0 on success, -1 otherwise |
| 260 | */ |
| 261 | static int rl2_read_seek(AVFormatContext *s, int stream_index, int64_t timestamp, int flags) |
| 262 | { |
| 263 | AVStream *st = s->streams[stream_index]; |
| 264 | Rl2DemuxContext *rl2 = s->priv_data; |
| 265 | int i; |
| 266 | int index = av_index_search_timestamp(st, timestamp, flags); |
| 267 | if(index < 0) |
| 268 | return -1; |
| 269 | |
| 270 | rl2->index_pos[stream_index] = index; |
| 271 | timestamp = st->index_entries[index].timestamp; |
| 272 | |
| 273 | for(i=0; i < s->nb_streams; i++){ |
| 274 | AVStream *st2 = s->streams[i]; |
| 275 | index = av_index_search_timestamp(st2, |
| 276 | av_rescale_q(timestamp, st->time_base, st2->time_base), |
| 277 | flags | AVSEEK_FLAG_BACKWARD); |
| 278 | |
| 279 | if(index < 0) |
| 280 | index = 0; |
| 281 | |
| 282 | rl2->index_pos[i] = index; |
| 283 | } |
| 284 | |
| 285 | return 0; |
| 286 | } |
| 287 | |
| 288 | AVInputFormat ff_rl2_demuxer = { |
| 289 | .name = "rl2", |
| 290 | .long_name = NULL_IF_CONFIG_SMALL("RL2"), |
| 291 | .priv_data_size = sizeof(Rl2DemuxContext), |
| 292 | .read_probe = rl2_probe, |
| 293 | .read_header = rl2_read_header, |
| 294 | .read_packet = rl2_read_packet, |
| 295 | .read_seek = rl2_read_seek, |
| 296 | }; |