FFmpeg: libavformat/tiertexseq.c Source File

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libavformat

tiertexseq.c

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1 /*

2 * Tiertex Limited SEQ File Demuxer

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 */

22 /**

23 * @file

24 * Tiertex Limited SEQ file demuxer

25 */

27 #include "libavutil/channel_layout.h"

28 #include "avformat.h"

29 #include "internal.h"

31 #define SEQ_FRAME_SIZE 6144

32 #define SEQ_FRAME_W 256

33 #define SEQ_FRAME_H 128

34 #define SEQ_NUM_FRAME_BUFFERS 30

35 #define SEQ_AUDIO_BUFFER_SIZE 882

36 #define SEQ_SAMPLE_RATE 22050

37 #define SEQ_FRAME_RATE 25

40 typedef struct TiertexSeqFrameBuffer {

41 int fill_size;

42 int data_size;

43 unsigned char *data;

44 } TiertexSeqFrameBuffer;

46 typedef struct SeqDemuxContext {

47 int audio_stream_index;

48 int video_stream_index;

49 int current_frame_pts;

50 int current_frame_offs;

51 TiertexSeqFrameBuffer frame_buffers[SEQ_NUM_FRAME_BUFFERS];

52 int frame_buffers_count;

53 unsigned int current_audio_data_size;

54 unsigned int current_audio_data_offs;

55 unsigned int current_pal_data_size;

56 unsigned int current_pal_data_offs;

57 unsigned int current_video_data_size;

58 unsigned char *current_video_data_ptr;

59 int audio_buffer_full;

60 } SeqDemuxContext;

63 static int seq_probe(AVProbeData *p)

64 {

65 int i;

67 if (p->buf_size < 258)

68 return 0;

70 /* there's no real header in a .seq file, the only thing they have in common */

71 /* is the first 256 bytes of the file which are always filled with 0 */

72 for (i = 0; i < 256; i++)

73 if (p->buf[i])

74 return 0;

76 if(p->buf[256]==0 && p->buf[257]==0)

77 return 0;

79 /* only one fourth of the score since the previous check is too naive */

80 return AVPROBE_SCORE_MAX / 4;

81 }

83 static int seq_init_frame_buffers(SeqDemuxContext *seq, AVIOContext *pb)

84 {

85 int i, sz;

86 TiertexSeqFrameBuffer *seq_buffer;

88 avio_seek(pb, 256, SEEK_SET);

90 for (i = 0; i < SEQ_NUM_FRAME_BUFFERS; i++) {

91 sz = avio_rl16(pb);

92 if (sz == 0)

93 break;

94 else {

95 seq_buffer = &seq->frame_buffers[i];

96 seq_buffer->fill_size = 0;

97 seq_buffer->data_size = sz;

98 seq_buffer->data = av_malloc(sz);

99 if (!seq_buffer->data)

100 return AVERROR(ENOMEM);

101 }

102 }

103 seq->frame_buffers_count = i;

104 return 0;

105 }

106

107 static int seq_fill_buffer(SeqDemuxContext *seq, AVIOContext *pb, int buffer_num, unsigned int data_offs, int data_size)

108 {

109 TiertexSeqFrameBuffer *seq_buffer;

110

111 if (buffer_num >= SEQ_NUM_FRAME_BUFFERS)

112 return AVERROR_INVALIDDATA;

113

114 seq_buffer = &seq->frame_buffers[buffer_num];

115 if (seq_buffer->fill_size + data_size > seq_buffer->data_size || data_size <= 0)

116 return AVERROR_INVALIDDATA;

117

118 avio_seek(pb, seq->current_frame_offs + data_offs, SEEK_SET);

119 if (avio_read(pb, seq_buffer->data + seq_buffer->fill_size, data_size) != data_size)

120 return AVERROR(EIO);

121

122 seq_buffer->fill_size += data_size;

123 return 0;

124 }

125

126 static int seq_parse_frame_data(SeqDemuxContext *seq, AVIOContext *pb)

127 {

128 unsigned int offset_table[4], buffer_num[4];

129 TiertexSeqFrameBuffer *seq_buffer;

130 int i, e, err;

131

132 seq->current_frame_offs += SEQ_FRAME_SIZE;

133 avio_seek(pb, seq->current_frame_offs, SEEK_SET);

134

135 /* sound data */

136 seq->current_audio_data_offs = avio_rl16(pb);

137 if (seq->current_audio_data_offs) {

138 seq->current_audio_data_size = SEQ_AUDIO_BUFFER_SIZE * 2;

139 } else {

140 seq->current_audio_data_size = 0;

141 }

142

143 /* palette data */

144 seq->current_pal_data_offs = avio_rl16(pb);

145 if (seq->current_pal_data_offs) {

146 seq->current_pal_data_size = 768;

147 } else {

148 seq->current_pal_data_size = 0;

149 }

150

151 /* video data */

152 for (i = 0; i < 4; i++)

153 buffer_num[i] = avio_r8(pb);

154

155 for (i = 0; i < 4; i++)

156 offset_table[i] = avio_rl16(pb);

157

158 for (i = 0; i < 3; i++) {

159 if (offset_table[i]) {

160 for (e = i + 1; e < 3 && offset_table[e] == 0; e++);

161 err = seq_fill_buffer(seq, pb, buffer_num[1 + i],

162 offset_table[i],

163 offset_table[e] - offset_table[i]);

164 if (err)

165 return err;

166 }

167 }

168

169 if (buffer_num[0] != 255) {

170 if (buffer_num[0] >= SEQ_NUM_FRAME_BUFFERS)

171 return AVERROR_INVALIDDATA;

172

173 seq_buffer = &seq->frame_buffers[buffer_num[0]];

174 seq->current_video_data_size = seq_buffer->fill_size;

175 seq->current_video_data_ptr = seq_buffer->data;

176 seq_buffer->fill_size = 0;

177 } else {

178 seq->current_video_data_size = 0;

179 seq->current_video_data_ptr = 0;

180 }

181

182 return 0;

183 }

184

185 static int seq_read_header(AVFormatContext *s)

186 {

187 int i, rc;

188 SeqDemuxContext *seq = s->priv_data;

189 AVIOContext *pb = s->pb;

190 AVStream *st;

191

192 /* init internal buffers */

193 rc = seq_init_frame_buffers(seq, pb);

194 if (rc)

195 return rc;

196

197 seq->current_frame_offs = 0;

198

199 /* preload (no audio data, just buffer operations related data) */

200 for (i = 1; i <= 100; i++) {

201 rc = seq_parse_frame_data(seq, pb);

202 if (rc)

203 return rc;

204 }

205

206 seq->current_frame_pts = 0;

207

208 seq->audio_buffer_full = 0;

209

210 /* initialize the video decoder stream */

211 st = avformat_new_stream(s, NULL);

212 if (!st)

213 return AVERROR(ENOMEM);

214

215 avpriv_set_pts_info(st, 32, 1, SEQ_FRAME_RATE);

216 seq->video_stream_index = st->index;

217 st->codec->codec_type = AVMEDIA_TYPE_VIDEO;

218 st->codec->codec_id = AV_CODEC_ID_TIERTEXSEQVIDEO;

219 st->codec->codec_tag = 0; /* no fourcc */

220 st->codec->width = SEQ_FRAME_W;

221 st->codec->height = SEQ_FRAME_H;

222

223 /* initialize the audio decoder stream */

224 st = avformat_new_stream(s, NULL);

225 if (!st)

226 return AVERROR(ENOMEM);

227

228 st->start_time = 0;

229 avpriv_set_pts_info(st, 32, 1, SEQ_SAMPLE_RATE);

230 seq->audio_stream_index = st->index;

231 st->codec->codec_type = AVMEDIA_TYPE_AUDIO;

232 st->codec->codec_id = AV_CODEC_ID_PCM_S16BE;

233 st->codec->codec_tag = 0; /* no tag */

234 st->codec->channels = 1;

235 st->codec->channel_layout = AV_CH_LAYOUT_MONO;

236 st->codec->sample_rate = SEQ_SAMPLE_RATE;

237 st->codec->bits_per_coded_sample = 16;

238 st->codec->bit_rate = st->codec->sample_rate * st->codec->bits_per_coded_sample * st->codec->channels;

239 st->codec->block_align = st->codec->channels * st->codec->bits_per_coded_sample / 8;

240

241 return 0;

242 }

243

244 static int seq_read_packet(AVFormatContext *s, AVPacket *pkt)

245 {

246 int rc;

247 SeqDemuxContext *seq = s->priv_data;

248 AVIOContext *pb = s->pb;

249

250 if (!seq->audio_buffer_full) {

251 rc = seq_parse_frame_data(seq, pb);

252 if (rc)

253 return rc;

254

255 /* video packet */

256 if (seq->current_pal_data_size + seq->current_video_data_size != 0) {

257 if (av_new_packet(pkt, 1 + seq->current_pal_data_size + seq->current_video_data_size))

258 return AVERROR(ENOMEM);

259

260 pkt->data[0] = 0;

261 if (seq->current_pal_data_size) {

262 pkt->data[0] |= 1;

263 avio_seek(pb, seq->current_frame_offs + seq->current_pal_data_offs, SEEK_SET);

264 if (avio_read(pb, &pkt->data[1], seq->current_pal_data_size) != seq->current_pal_data_size)

265 return AVERROR(EIO);

266 }

267 if (seq->current_video_data_size) {

268 pkt->data[0] |= 2;

269 memcpy(&pkt->data[1 + seq->current_pal_data_size],

270 seq->current_video_data_ptr,

271 seq->current_video_data_size);

272 }

273 pkt->stream_index = seq->video_stream_index;

274 pkt->pts = seq->current_frame_pts;

275

276 /* sound buffer will be processed on next read_packet() call */

277 seq->audio_buffer_full = 1;

278 return 0;

279 }

280 }

281

282 /* audio packet */

283 if (seq->current_audio_data_offs == 0) /* end of data reached */

284 return AVERROR(EIO);

285

286 avio_seek(pb, seq->current_frame_offs + seq->current_audio_data_offs, SEEK_SET);

287 rc = av_get_packet(pb, pkt, seq->current_audio_data_size);

288 if (rc < 0)

289 return rc;

290

291 pkt->stream_index = seq->audio_stream_index;

292 seq->current_frame_pts++;

293

294 seq->audio_buffer_full = 0;

295 return 0;

296 }

297

298 static int seq_read_close(AVFormatContext *s)

299 {

300 int i;

301 SeqDemuxContext *seq = s->priv_data;

302

303 for (i = 0; i < SEQ_NUM_FRAME_BUFFERS; i++)

304 av_free(seq->frame_buffers[i].data);

305

306 return 0;

307 }

308

309 AVInputFormat ff_tiertexseq_demuxer = {

310 .name = "tiertexseq",

311 .long_name = NULL_IF_CONFIG_SMALL("Tiertex Limited SEQ"),

312 .priv_data_size = sizeof(SeqDemuxContext),

313 .read_probe = seq_probe,

314 .read_header = seq_read_header,

315 .read_packet = seq_read_packet,

316 .read_close = seq_read_close,

317 };

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