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ffmpeg / libavformat / ipmovie.c @ 649b918c

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/*
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 * Interplay MVE File Demuxer
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 * Copyright (c) 2003 The ffmpeg Project
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 *
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 * This library is free software; you can redistribute it and/or
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 * modify it under the terms of the GNU Lesser General Public
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 * License as published by the Free Software Foundation; either
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 * version 2 of the License, or (at your option) any later version.
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 *
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 * This library is distributed in the hope that it will be useful,
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 * but WITHOUT ANY WARRANTY; without even the implied warranty of
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 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
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 * Lesser General Public License for more details.
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 *
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 * You should have received a copy of the GNU Lesser General Public
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 * License along with this library; if not, write to the Free Software
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 * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
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 */
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/**
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 * @file ipmovie.c
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 * Interplay MVE file demuxer
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 * by Mike Melanson (melanson@pcisys.net)
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 * For more information regarding the Interplay MVE file format, visit:
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 *   http://www.pcisys.net/~melanson/codecs/
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 * The aforementioned site also contains a command line utility for parsing
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 * IP MVE files so that you can get a good idea of the typical structure of
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 * such files. This demuxer is not the best example to use if you are trying
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 * to write your own as it uses a rather roundabout approach for splitting
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 * up and sending out the chunks.
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 */
32

    
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#include "avformat.h"
34

    
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/* debugging support: #define DEBUG_IPMOVIE as non-zero to see extremely
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 * verbose information about the demux process */
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#define DEBUG_IPMOVIE 0
38

    
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#if DEBUG_IPMOVIE
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#define debug_ipmovie printf
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#else
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static inline void debug_ipmovie(const char *format, ...) { }
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#endif
44

    
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#define IPMOVIE_SIGNATURE "Interplay MVE File\x1A\0"
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#define IPMOVIE_SIGNATURE_SIZE 20
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#define CHUNK_PREAMBLE_SIZE 4
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#define OPCODE_PREAMBLE_SIZE 4
49

    
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#define CHUNK_INIT_AUDIO   0x0000
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#define CHUNK_AUDIO_ONLY   0x0001
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#define CHUNK_INIT_VIDEO   0x0002
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#define CHUNK_VIDEO        0x0003
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#define CHUNK_SHUTDOWN     0x0004
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#define CHUNK_END          0x0005
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/* these last types are used internally */
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#define CHUNK_DONE         0xFFFC
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#define CHUNK_NOMEM        0xFFFD
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#define CHUNK_EOF          0xFFFE
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#define CHUNK_BAD          0xFFFF
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62
#define OPCODE_END_OF_STREAM           0x00
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#define OPCODE_END_OF_CHUNK            0x01
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#define OPCODE_CREATE_TIMER            0x02
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#define OPCODE_INIT_AUDIO_BUFFERS      0x03
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#define OPCODE_START_STOP_AUDIO        0x04
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#define OPCODE_INIT_VIDEO_BUFFERS      0x05
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#define OPCODE_UNKNOWN_06              0x06
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#define OPCODE_SEND_BUFFER             0x07
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#define OPCODE_AUDIO_FRAME             0x08
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#define OPCODE_SILENCE_FRAME           0x09
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#define OPCODE_INIT_VIDEO_MODE         0x0A
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#define OPCODE_CREATE_GRADIENT         0x0B
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#define OPCODE_SET_PALETTE             0x0C
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#define OPCODE_SET_PALETTE_COMPRESSED  0x0D
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#define OPCODE_UNKNOWN_0E              0x0E
77
#define OPCODE_SET_DECODING_MAP        0x0F
78
#define OPCODE_UNKNOWN_10              0x10
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#define OPCODE_VIDEO_DATA              0x11
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#define OPCODE_UNKNOWN_12              0x12
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#define OPCODE_UNKNOWN_13              0x13
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#define OPCODE_UNKNOWN_14              0x14
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#define OPCODE_UNKNOWN_15              0x15
84

    
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#define PALETTE_COUNT 256
86

    
87
typedef struct IPMVEContext {
88

    
89
    unsigned char *buf;
90
    int buf_size;
91

    
92
    float fps;
93
    int frame_pts_inc;
94

    
95
    unsigned int video_width;
96
    unsigned int video_height;
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    int64_t video_pts;
98

    
99
    unsigned int audio_bits;
100
    unsigned int audio_channels;
101
    unsigned int audio_sample_rate;
102
    unsigned int audio_type;
103
    unsigned int audio_frame_count;
104

    
105
    int video_stream_index;
106
    int audio_stream_index;
107

    
108
    offset_t audio_chunk_offset;
109
    int audio_chunk_size;
110
    offset_t video_chunk_offset;
111
    int video_chunk_size;
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    offset_t decode_map_chunk_offset;
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    int decode_map_chunk_size;
114

    
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    offset_t next_chunk_offset;
116

    
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    AVPaletteControl palette_control;
118

    
119
} IPMVEContext;
120

    
121
static int load_ipmovie_packet(IPMVEContext *s, ByteIOContext *pb, 
122
    AVPacket *pkt) {
123

    
124
    int chunk_type;
125
    int64_t audio_pts = 0;
126

    
127
    if (s->audio_chunk_offset) {
128

    
129
        /* adjust for PCM audio by skipping chunk header */
130
        if (s->audio_type != CODEC_ID_INTERPLAY_DPCM) {
131
            s->audio_chunk_offset += 6;
132
            s->audio_chunk_size -= 6;
133
        }
134

    
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        url_fseek(pb, s->audio_chunk_offset, SEEK_SET);
136
        s->audio_chunk_offset = 0;
137

    
138
        /* figure out the audio pts */
139
        audio_pts = 90000;
140
        audio_pts *= s->audio_frame_count;
141
        audio_pts /= s->audio_sample_rate;
142

    
143
        if (av_new_packet(pkt, s->audio_chunk_size))
144
            return CHUNK_NOMEM;
145

    
146
        pkt->stream_index = s->audio_stream_index;
147
        pkt->pts = audio_pts;
148
        if (get_buffer(pb, pkt->data, s->audio_chunk_size) != 
149
            s->audio_chunk_size) {
150
            av_free_packet(pkt);
151
            return CHUNK_EOF;
152
        }
153

    
154
        /* audio frame maintenance */
155
        if (s->audio_type != CODEC_ID_INTERPLAY_DPCM)
156
            s->audio_frame_count +=
157
            (s->audio_chunk_size / s->audio_channels / (s->audio_bits / 8));
158
        else
159
            s->audio_frame_count +=
160
                (s->audio_chunk_size - 6) / s->audio_channels;
161

    
162
        debug_ipmovie("sending audio frame with pts %lld (%d audio frames)\n",
163
            audio_pts, s->audio_frame_count);
164

    
165
        chunk_type = CHUNK_VIDEO;
166

    
167
    } else if (s->decode_map_chunk_offset) {
168

    
169
        /* send both the decode map and the video data together */
170

    
171
        if (av_new_packet(pkt, s->decode_map_chunk_size + s->video_chunk_size))
172
            return CHUNK_NOMEM;
173

    
174
        url_fseek(pb, s->decode_map_chunk_offset, SEEK_SET);
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        s->decode_map_chunk_offset = 0;
176

    
177
        if (get_buffer(pb, pkt->data, s->decode_map_chunk_size) != 
178
            s->decode_map_chunk_size) {
179
            av_free_packet(pkt);
180
            return CHUNK_EOF;
181
        }
182

    
183
        url_fseek(pb, s->video_chunk_offset, SEEK_SET);
184
        s->video_chunk_offset = 0;
185

    
186
        if (get_buffer(pb, pkt->data + s->decode_map_chunk_size,
187
            s->video_chunk_size) != s->video_chunk_size) {
188
            av_free_packet(pkt);
189
            return CHUNK_EOF;
190
        }
191

    
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        pkt->stream_index = s->video_stream_index;
193
        pkt->pts = s->video_pts;
194

    
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        debug_ipmovie("sending video frame with pts %lld\n",
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            pkt->pts);
197

    
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        s->video_pts += s->frame_pts_inc;
199

    
200
        chunk_type = CHUNK_VIDEO;
201

    
202
    } else {
203

    
204
        url_fseek(pb, s->next_chunk_offset, SEEK_SET);
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        chunk_type = CHUNK_DONE;
206

    
207
    }
208

    
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    return chunk_type;
210
}
211

    
212
/* This function loads and processes a single chunk in an IP movie file.
213
 * It returns the type of chunk that was processed. */
214
static int process_ipmovie_chunk(IPMVEContext *s, ByteIOContext *pb, 
215
    AVPacket *pkt)
216
{
217
    unsigned char chunk_preamble[CHUNK_PREAMBLE_SIZE];
218
    int chunk_type;
219
    int chunk_size;
220
    unsigned char opcode_preamble[OPCODE_PREAMBLE_SIZE];
221
    unsigned char opcode_type;
222
    unsigned char opcode_version;
223
    int opcode_size;
224
    unsigned char scratch[1024];
225
    int i, j;
226
    int first_color, last_color;
227
    int audio_flags;
228
    unsigned char r, g, b;
229

    
230
    /* see if there are any pending packets */
231
    chunk_type = load_ipmovie_packet(s, pb, pkt);
232
    if ((chunk_type == CHUNK_VIDEO) && (chunk_type != CHUNK_DONE))
233
        return chunk_type;
234

    
235
    /* read the next chunk, wherever the file happens to be pointing */
236
    if (url_feof(pb))
237
        return CHUNK_EOF;
238
    if (get_buffer(pb, chunk_preamble, CHUNK_PREAMBLE_SIZE) !=
239
        CHUNK_PREAMBLE_SIZE)
240
        return CHUNK_BAD;
241
    chunk_size = LE_16(&chunk_preamble[0]);
242
    chunk_type = LE_16(&chunk_preamble[2]);
243

    
244
    debug_ipmovie("chunk type 0x%04X, 0x%04X bytes: ", chunk_type, chunk_size);
245

    
246
    switch (chunk_type) {
247

    
248
    case CHUNK_INIT_AUDIO:
249
        debug_ipmovie("initialize audio\n");
250
        break;
251

    
252
    case CHUNK_AUDIO_ONLY:
253
        debug_ipmovie("audio only\n");
254
        break;
255

    
256
    case CHUNK_INIT_VIDEO:
257
        debug_ipmovie("initialize video\n");
258
        break;
259

    
260
    case CHUNK_VIDEO:
261
        debug_ipmovie("video (and audio)\n");
262
        break;
263

    
264
    case CHUNK_SHUTDOWN:
265
        debug_ipmovie("shutdown\n");
266
        break;
267

    
268
    case CHUNK_END:
269
        debug_ipmovie("end\n");
270
        break;
271

    
272
    default:
273
        debug_ipmovie("invalid chunk\n");
274
        chunk_type = CHUNK_BAD;
275
        break;
276

    
277
    }
278

    
279
    while ((chunk_size > 0) && (chunk_type != CHUNK_BAD)) {
280

    
281
        /* read the next chunk, wherever the file happens to be pointing */
282
       if (url_feof(pb)) {
283
            chunk_type = CHUNK_EOF;
284
            break;
285
        }
286
        if (get_buffer(pb, opcode_preamble, CHUNK_PREAMBLE_SIZE) !=
287
            CHUNK_PREAMBLE_SIZE) {
288
            chunk_type = CHUNK_BAD;
289
            break;
290
        }
291

    
292
        opcode_size = LE_16(&opcode_preamble[0]);
293
        opcode_type = opcode_preamble[2];
294
        opcode_version = opcode_preamble[3];
295

    
296
        chunk_size -= OPCODE_PREAMBLE_SIZE;
297
        chunk_size -= opcode_size;
298
        if (chunk_size < 0) {
299
            debug_ipmovie("chunk_size countdown just went negative\n");
300
            chunk_type = CHUNK_BAD;
301
            break;
302
        }
303

    
304
        debug_ipmovie("  opcode type %02X, version %d, 0x%04X bytes: ",
305
            opcode_type, opcode_version, opcode_size);
306
        switch (opcode_type) {
307

    
308
        case OPCODE_END_OF_STREAM:
309
            debug_ipmovie("end of stream\n");
310
            url_fseek(pb, opcode_size, SEEK_CUR);
311
            break;
312

    
313
        case OPCODE_END_OF_CHUNK:
314
            debug_ipmovie("end of chunk\n");
315
            url_fseek(pb, opcode_size, SEEK_CUR);
316
            break;
317

    
318
        case OPCODE_CREATE_TIMER:
319
            debug_ipmovie("create timer\n");
320
            if ((opcode_version > 0) || (opcode_size > 6)) {
321
                debug_ipmovie("bad create_timer opcode\n");
322
                chunk_type = CHUNK_BAD;
323
                break;
324
            }
325
            if (get_buffer(pb, scratch, opcode_size) !=
326
                opcode_size) {
327
                chunk_type = CHUNK_BAD;
328
                break;
329
            }
330
            s->fps = 1000000.0 / (LE_32(&scratch[0]) * LE_16(&scratch[4]));
331
            s->frame_pts_inc = 90000 / s->fps;
332
            debug_ipmovie("  %.2f frames/second (timer div = %d, subdiv = %d)\n",
333
                s->fps, LE_32(&scratch[0]), LE_16(&scratch[4]));
334
            break;
335

    
336
        case OPCODE_INIT_AUDIO_BUFFERS:
337
            debug_ipmovie("initialize audio buffers\n");
338
            if ((opcode_version > 1) || (opcode_size > 10)) {
339
                debug_ipmovie("bad init_audio_buffers opcode\n");
340
                chunk_type = CHUNK_BAD;
341
                break;
342
            }
343
            if (get_buffer(pb, scratch, opcode_size) !=
344
                opcode_size) {
345
                chunk_type = CHUNK_BAD;
346
                break;
347
            }
348
            s->audio_sample_rate = LE_16(&scratch[4]);
349
            audio_flags = LE_16(&scratch[2]);
350
            /* bit 0 of the flags: 0 = mono, 1 = stereo */
351
            s->audio_channels = (audio_flags & 1) + 1;
352
            /* bit 1 of the flags: 0 = 8 bit, 1 = 16 bit */
353
            s->audio_bits = (((audio_flags >> 1) & 1) + 1) * 8;
354
            /* bit 2 indicates compressed audio in version 1 opcode */
355
            if ((opcode_version == 1) && (audio_flags & 0x4))
356
                s->audio_type = CODEC_ID_INTERPLAY_DPCM;
357
            else if (s->audio_bits == 16)
358
                s->audio_type = CODEC_ID_PCM_S16LE;
359
            else
360
                s->audio_type = CODEC_ID_PCM_U8;
361
            debug_ipmovie("audio: %d bits, %d Hz, %s, %s format\n",
362
                s->audio_bits,
363
                s->audio_sample_rate,
364
                (s->audio_channels == 2) ? "stereo" : "mono",
365
                (s->audio_type == CODEC_ID_INTERPLAY_DPCM) ? 
366
                "Interplay audio" : "PCM");
367
            break;
368

    
369
        case OPCODE_START_STOP_AUDIO:
370
            debug_ipmovie("start/stop audio\n");
371
            url_fseek(pb, opcode_size, SEEK_CUR);
372
            break;
373

    
374
        case OPCODE_INIT_VIDEO_BUFFERS:
375
            debug_ipmovie("initialize video buffers\n");
376
            if ((opcode_version > 2) || (opcode_size > 8)) {
377
                debug_ipmovie("bad init_video_buffers opcode\n");
378
                chunk_type = CHUNK_BAD;
379
                break;
380
            }
381
            if (get_buffer(pb, scratch, opcode_size) !=
382
                opcode_size) {
383
                chunk_type = CHUNK_BAD;
384
                break;
385
            }
386
            s->video_width = LE_16(&scratch[0]) * 8;
387
            s->video_height = LE_16(&scratch[2]) * 8;
388
            debug_ipmovie("video resolution: %d x %d\n",
389
                s->video_width, s->video_height);
390
            break;
391

    
392
        case OPCODE_UNKNOWN_06:
393
        case OPCODE_UNKNOWN_0E:
394
        case OPCODE_UNKNOWN_10:
395
        case OPCODE_UNKNOWN_12:
396
        case OPCODE_UNKNOWN_13:
397
        case OPCODE_UNKNOWN_14:
398
        case OPCODE_UNKNOWN_15:
399
            debug_ipmovie("unknown (but documented) opcode %02X\n", opcode_type);
400
            url_fseek(pb, opcode_size, SEEK_CUR);
401
            break;
402

    
403
        case OPCODE_SEND_BUFFER:
404
            debug_ipmovie("send buffer\n");
405
            url_fseek(pb, opcode_size, SEEK_CUR);
406
            break;
407

    
408
        case OPCODE_AUDIO_FRAME:
409
            debug_ipmovie("audio frame\n");
410

    
411
            /* log position and move on for now */
412
            s->audio_chunk_offset = url_ftell(pb);
413
            s->audio_chunk_size = opcode_size;
414
            url_fseek(pb, opcode_size, SEEK_CUR);
415
            break;
416

    
417
        case OPCODE_SILENCE_FRAME:
418
            debug_ipmovie("silence frame\n");
419
            url_fseek(pb, opcode_size, SEEK_CUR);
420
            break;
421

    
422
        case OPCODE_INIT_VIDEO_MODE:
423
            debug_ipmovie("initialize video mode\n");
424
            url_fseek(pb, opcode_size, SEEK_CUR);
425
            break;
426

    
427
        case OPCODE_CREATE_GRADIENT:
428
            debug_ipmovie("create gradient\n");
429
            url_fseek(pb, opcode_size, SEEK_CUR);
430
            break;
431

    
432
        case OPCODE_SET_PALETTE:
433
            debug_ipmovie("set palette\n");
434
            /* check for the logical maximum palette size
435
             * (3 * 256 + 4 bytes) */
436
            if (opcode_size > 0x304) {
437
                debug_ipmovie("demux_ipmovie: set_palette opcode too large\n");
438
                chunk_type = CHUNK_BAD;
439
                break;
440
            }
441
            if (get_buffer(pb, scratch, opcode_size) != opcode_size) {
442
                chunk_type = CHUNK_BAD;
443
                break;
444
            }
445

    
446
            /* load the palette into internal data structure */
447
            first_color = LE_16(&scratch[0]);
448
            last_color = first_color + LE_16(&scratch[2]) - 1;
449
            /* sanity check (since they are 16 bit values) */
450
            if ((first_color > 0xFF) || (last_color > 0xFF)) {
451
                debug_ipmovie("demux_ipmovie: set_palette indices out of range (%d -> %d)\n",
452
                    first_color, last_color);
453
                chunk_type = CHUNK_BAD;
454
                break;
455
            }
456
            j = 4;  /* offset of first palette data */
457
            for (i = first_color; i <= last_color; i++) {
458
                /* the palette is stored as a 6-bit VGA palette, thus each
459
                 * component is shifted up to a 8-bit range */
460
                r = scratch[j++] * 4;
461
                g = scratch[j++] * 4;
462
                b = scratch[j++] * 4;
463
                s->palette_control.palette[i] = (r << 16) | (g << 8) | (b);
464
            }
465
            /* indicate a palette change */
466
            s->palette_control.palette_changed = 1;
467
            break;
468

    
469
        case OPCODE_SET_PALETTE_COMPRESSED:
470
            debug_ipmovie("set palette compressed\n");
471
            url_fseek(pb, opcode_size, SEEK_CUR);
472
            break;
473

    
474
        case OPCODE_SET_DECODING_MAP:
475
            debug_ipmovie("set decoding map\n");
476

    
477
            /* log position and move on for now */
478
            s->decode_map_chunk_offset = url_ftell(pb);
479
            s->decode_map_chunk_size = opcode_size;
480
            url_fseek(pb, opcode_size, SEEK_CUR);
481
            break;
482

    
483
        case OPCODE_VIDEO_DATA:
484
            debug_ipmovie("set video data\n");
485

    
486
            /* log position and move on for now */
487
            s->video_chunk_offset = url_ftell(pb);
488
            s->video_chunk_size = opcode_size;
489
            url_fseek(pb, opcode_size, SEEK_CUR);
490
            break;
491

    
492
        default:
493
            debug_ipmovie("*** unknown opcode type\n");
494
            chunk_type = CHUNK_BAD;
495
            break;
496

    
497
        }
498
    }
499

    
500
    /* make a note of where the stream is sitting */
501
    s->next_chunk_offset = url_ftell(pb);
502

    
503
    /* dispatch the first of any pending packets */
504
    if ((chunk_type == CHUNK_VIDEO) || (chunk_type == CHUNK_AUDIO_ONLY))
505
        chunk_type = load_ipmovie_packet(s, pb, pkt);
506

    
507
    return chunk_type;
508
}
509

    
510
static int ipmovie_probe(AVProbeData *p)
511
{
512
    if (p->buf_size < IPMOVIE_SIGNATURE_SIZE)
513
        return 0;
514
    if (strncmp(p->buf, IPMOVIE_SIGNATURE, IPMOVIE_SIGNATURE_SIZE) != 0)
515
        return 0;
516

    
517
    return AVPROBE_SCORE_MAX;
518
}
519

    
520
static int ipmovie_read_header(AVFormatContext *s,
521
                               AVFormatParameters *ap)
522
{
523
    IPMVEContext *ipmovie = (IPMVEContext *)s->priv_data;
524
    ByteIOContext *pb = &s->pb;
525
    AVPacket pkt;
526
    AVStream *st;
527
    unsigned char chunk_preamble[CHUNK_PREAMBLE_SIZE];
528
    int chunk_type;
529

    
530
    /* initialize private context members */
531
    ipmovie->video_pts = ipmovie->audio_frame_count = 0;
532
    ipmovie->audio_chunk_offset = ipmovie->video_chunk_offset =
533
    ipmovie->decode_map_chunk_offset = 0;
534

    
535
    /* on the first read, this will position the stream at the first chunk */
536
    ipmovie->next_chunk_offset = IPMOVIE_SIGNATURE_SIZE + 6;
537

    
538
    /* process the first chunk which should be CHUNK_INIT_VIDEO */
539
    if (process_ipmovie_chunk(ipmovie, pb, &pkt) != CHUNK_INIT_VIDEO)
540
        return AVERROR_INVALIDDATA;
541

    
542
    /* peek ahead to the next chunk-- if it is an init audio chunk, process
543
     * it; if it is the first video chunk, this is a silent file */
544
    if (get_buffer(pb, chunk_preamble, CHUNK_PREAMBLE_SIZE) !=
545
        CHUNK_PREAMBLE_SIZE)
546
        return AVERROR_IO;
547
    chunk_type = LE_16(&chunk_preamble[2]);
548
    url_fseek(pb, -CHUNK_PREAMBLE_SIZE, SEEK_CUR);
549

    
550
    if (chunk_type == CHUNK_VIDEO)
551
        ipmovie->audio_type = 0;  /* no audio */
552
    else if (process_ipmovie_chunk(ipmovie, pb, &pkt) != CHUNK_INIT_AUDIO)
553
        return AVERROR_INVALIDDATA;
554

    
555
    /* initialize the stream decoders */
556
    st = av_new_stream(s, 0);
557
    if (!st)
558
        return AVERROR_NOMEM;
559
    av_set_pts_info(st, 33, 1, 90000);
560
    ipmovie->video_stream_index = st->index;
561
    st->codec.codec_type = CODEC_TYPE_VIDEO;
562
    st->codec.codec_id = CODEC_ID_INTERPLAY_VIDEO;
563
    st->codec.codec_tag = 0;  /* no fourcc */
564
    st->codec.width = ipmovie->video_width;
565
    st->codec.height = ipmovie->video_height;
566

    
567
    /* palette considerations */
568
    st->codec.palctrl = &ipmovie->palette_control;
569

    
570
    if (ipmovie->audio_type) {
571
        st = av_new_stream(s, 0);
572
        if (!st)
573
            return AVERROR_NOMEM;
574
        av_set_pts_info(st, 33, 1, 90000);
575
        ipmovie->audio_stream_index = st->index;
576
        st->codec.codec_type = CODEC_TYPE_AUDIO;
577
        st->codec.codec_id = ipmovie->audio_type;
578
        st->codec.codec_tag = 0;  /* no tag */
579
        st->codec.channels = ipmovie->audio_channels;
580
        st->codec.sample_rate = ipmovie->audio_sample_rate;
581
        st->codec.bits_per_sample = ipmovie->audio_bits;
582
        st->codec.bit_rate = st->codec.channels * st->codec.sample_rate *
583
            st->codec.bits_per_sample;
584
        if (st->codec.codec_id == CODEC_ID_INTERPLAY_DPCM)
585
            st->codec.bit_rate /= 2;
586
        st->codec.block_align = st->codec.channels * st->codec.bits_per_sample;
587
    }
588

    
589
    return 0;
590
}
591

    
592
static int ipmovie_read_packet(AVFormatContext *s,
593
                               AVPacket *pkt)
594
{
595
    IPMVEContext *ipmovie = (IPMVEContext *)s->priv_data;
596
    ByteIOContext *pb = &s->pb;
597
    int ret;
598

    
599
    ret = process_ipmovie_chunk(ipmovie, pb, pkt);
600
    if (ret == CHUNK_BAD)
601
        ret = AVERROR_INVALIDDATA;
602
    else if (ret == CHUNK_EOF)
603
        ret = AVERROR_IO;
604
    else if (ret == CHUNK_NOMEM)
605
        ret = AVERROR_NOMEM;
606
    else
607
        ret = 0;
608

    
609
    return ret;
610
}
611

    
612
static int ipmovie_read_close(AVFormatContext *s)
613
{
614
//    IPMVEContext *ipmovie = (IPMVEContext *)s->priv_data;
615

    
616
    return 0;
617
}
618

    
619
static AVInputFormat ipmovie_iformat = {
620
    "ipmovie",
621
    "Interplay MVE format",
622
    sizeof(IPMVEContext),
623
    ipmovie_probe,
624
    ipmovie_read_header,
625
    ipmovie_read_packet,
626
    ipmovie_read_close,
627
};
628

    
629
int ipmovie_init(void)
630
{
631
    av_register_input_format(&ipmovie_iformat);
632
    return 0;
633
}
634