blob: 0bec8f1d9aba8b850a089c25315e1228591b59fb
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 method */ |
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->codecpar->codec_type = AVMEDIA_TYPE_VIDEO; |
119 | st->codecpar->codec_id = AV_CODEC_ID_RL2; |
120 | st->codecpar->codec_tag = 0; /* no fourcc */ |
121 | st->codecpar->width = 320; |
122 | st->codecpar->height = 200; |
123 | |
124 | /** allocate and fill extradata */ |
125 | st->codecpar->extradata_size = EXTRADATA1_SIZE; |
126 | |
127 | if(signature == RLV3_TAG && back_size > 0) |
128 | st->codecpar->extradata_size += back_size; |
129 | |
130 | if(ff_get_extradata(s, st->codecpar, pb, st->codecpar->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->codecpar->codec_type = AVMEDIA_TYPE_AUDIO; |
147 | st->codecpar->codec_id = AV_CODEC_ID_PCM_U8; |
148 | st->codecpar->codec_tag = 1; |
149 | st->codecpar->channels = channels; |
150 | st->codecpar->bits_per_coded_sample = 8; |
151 | st->codecpar->sample_rate = rate; |
152 | st->codecpar->bit_rate = st->codecpar->channels * st->codecpar->sample_rate * |
153 | st->codecpar->bits_per_coded_sample; |
154 | st->codecpar->block_align = st->codecpar->channels * |
155 | st->codecpar->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_packet_unref(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 | }; |
297 |