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ffmpeg / libavformat / ipmovie.c @ 01f4895c

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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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20
/**
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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
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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
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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
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#define OPCODE_SET_DECODING_MAP        0x0F
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#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

    
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    float fps;
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    int frame_pts_inc;
94

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

    
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    unsigned int audio_bits;
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    unsigned int audio_channels;
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    unsigned int audio_sample_rate;
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    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;
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    int audio_chunk_size;
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    offset_t video_chunk_offset;
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    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

    
117
    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;
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        }
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135
        url_fseek(pb, s->audio_chunk_offset, SEEK_SET);
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        s->audio_chunk_offset = 0;
137

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

    
143
        if (s->audio_chunk_size != av_get_packet(pb, pkt, s->audio_chunk_size))
144
            return CHUNK_EOF;
145

    
146
        pkt->stream_index = s->audio_stream_index;
147
        pkt->pts = audio_pts;
148

    
149
        /* audio frame maintenance */
150
        if (s->audio_type != CODEC_ID_INTERPLAY_DPCM)
151
            s->audio_frame_count +=
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            (s->audio_chunk_size / s->audio_channels / (s->audio_bits / 8));
153
        else
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            s->audio_frame_count +=
155
                (s->audio_chunk_size - 6) / s->audio_channels;
156

    
157
        debug_ipmovie("sending audio frame with pts %lld (%d audio frames)\n",
158
            audio_pts, s->audio_frame_count);
159

    
160
        chunk_type = CHUNK_VIDEO;
161

    
162
    } else if (s->decode_map_chunk_offset) {
163

    
164
        /* send both the decode map and the video data together */
165

    
166
        if (av_new_packet(pkt, s->decode_map_chunk_size + s->video_chunk_size))
167
            return CHUNK_NOMEM;
168

    
169
        pkt->pos= s->decode_map_chunk_offset;
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        url_fseek(pb, s->decode_map_chunk_offset, SEEK_SET);
171
        s->decode_map_chunk_offset = 0;
172

    
173
        if (get_buffer(pb, pkt->data, s->decode_map_chunk_size) != 
174
            s->decode_map_chunk_size) {
175
            av_free_packet(pkt);
176
            return CHUNK_EOF;
177
        }
178

    
179
        url_fseek(pb, s->video_chunk_offset, SEEK_SET);
180
        s->video_chunk_offset = 0;
181

    
182
        if (get_buffer(pb, pkt->data + s->decode_map_chunk_size,
183
            s->video_chunk_size) != s->video_chunk_size) {
184
            av_free_packet(pkt);
185
            return CHUNK_EOF;
186
        }
187

    
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        pkt->stream_index = s->video_stream_index;
189
        pkt->pts = s->video_pts;
190

    
191
        debug_ipmovie("sending video frame with pts %lld\n",
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            pkt->pts);
193

    
194
        s->video_pts += s->frame_pts_inc;
195

    
196
        chunk_type = CHUNK_VIDEO;
197

    
198
    } else {
199

    
200
        url_fseek(pb, s->next_chunk_offset, SEEK_SET);
201
        chunk_type = CHUNK_DONE;
202

    
203
    }
204

    
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    return chunk_type;
206
}
207

    
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/* This function loads and processes a single chunk in an IP movie file.
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 * It returns the type of chunk that was processed. */
210
static int process_ipmovie_chunk(IPMVEContext *s, ByteIOContext *pb, 
211
    AVPacket *pkt)
212
{
213
    unsigned char chunk_preamble[CHUNK_PREAMBLE_SIZE];
214
    int chunk_type;
215
    int chunk_size;
216
    unsigned char opcode_preamble[OPCODE_PREAMBLE_SIZE];
217
    unsigned char opcode_type;
218
    unsigned char opcode_version;
219
    int opcode_size;
220
    unsigned char scratch[1024];
221
    int i, j;
222
    int first_color, last_color;
223
    int audio_flags;
224
    unsigned char r, g, b;
225

    
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    /* see if there are any pending packets */
227
    chunk_type = load_ipmovie_packet(s, pb, pkt);
228
    if ((chunk_type == CHUNK_VIDEO) && (chunk_type != CHUNK_DONE))
229
        return chunk_type;
230

    
231
    /* read the next chunk, wherever the file happens to be pointing */
232
    if (url_feof(pb))
233
        return CHUNK_EOF;
234
    if (get_buffer(pb, chunk_preamble, CHUNK_PREAMBLE_SIZE) !=
235
        CHUNK_PREAMBLE_SIZE)
236
        return CHUNK_BAD;
237
    chunk_size = LE_16(&chunk_preamble[0]);
238
    chunk_type = LE_16(&chunk_preamble[2]);
239

    
240
    debug_ipmovie("chunk type 0x%04X, 0x%04X bytes: ", chunk_type, chunk_size);
241

    
242
    switch (chunk_type) {
243

    
244
    case CHUNK_INIT_AUDIO:
245
        debug_ipmovie("initialize audio\n");
246
        break;
247

    
248
    case CHUNK_AUDIO_ONLY:
249
        debug_ipmovie("audio only\n");
250
        break;
251

    
252
    case CHUNK_INIT_VIDEO:
253
        debug_ipmovie("initialize video\n");
254
        break;
255

    
256
    case CHUNK_VIDEO:
257
        debug_ipmovie("video (and audio)\n");
258
        break;
259

    
260
    case CHUNK_SHUTDOWN:
261
        debug_ipmovie("shutdown\n");
262
        break;
263

    
264
    case CHUNK_END:
265
        debug_ipmovie("end\n");
266
        break;
267

    
268
    default:
269
        debug_ipmovie("invalid chunk\n");
270
        chunk_type = CHUNK_BAD;
271
        break;
272

    
273
    }
274

    
275
    while ((chunk_size > 0) && (chunk_type != CHUNK_BAD)) {
276

    
277
        /* read the next chunk, wherever the file happens to be pointing */
278
       if (url_feof(pb)) {
279
            chunk_type = CHUNK_EOF;
280
            break;
281
        }
282
        if (get_buffer(pb, opcode_preamble, CHUNK_PREAMBLE_SIZE) !=
283
            CHUNK_PREAMBLE_SIZE) {
284
            chunk_type = CHUNK_BAD;
285
            break;
286
        }
287

    
288
        opcode_size = LE_16(&opcode_preamble[0]);
289
        opcode_type = opcode_preamble[2];
290
        opcode_version = opcode_preamble[3];
291

    
292
        chunk_size -= OPCODE_PREAMBLE_SIZE;
293
        chunk_size -= opcode_size;
294
        if (chunk_size < 0) {
295
            debug_ipmovie("chunk_size countdown just went negative\n");
296
            chunk_type = CHUNK_BAD;
297
            break;
298
        }
299

    
300
        debug_ipmovie("  opcode type %02X, version %d, 0x%04X bytes: ",
301
            opcode_type, opcode_version, opcode_size);
302
        switch (opcode_type) {
303

    
304
        case OPCODE_END_OF_STREAM:
305
            debug_ipmovie("end of stream\n");
306
            url_fseek(pb, opcode_size, SEEK_CUR);
307
            break;
308

    
309
        case OPCODE_END_OF_CHUNK:
310
            debug_ipmovie("end of chunk\n");
311
            url_fseek(pb, opcode_size, SEEK_CUR);
312
            break;
313

    
314
        case OPCODE_CREATE_TIMER:
315
            debug_ipmovie("create timer\n");
316
            if ((opcode_version > 0) || (opcode_size > 6)) {
317
                debug_ipmovie("bad create_timer opcode\n");
318
                chunk_type = CHUNK_BAD;
319
                break;
320
            }
321
            if (get_buffer(pb, scratch, opcode_size) !=
322
                opcode_size) {
323
                chunk_type = CHUNK_BAD;
324
                break;
325
            }
326
            s->fps = 1000000.0 / (LE_32(&scratch[0]) * LE_16(&scratch[4]));
327
            s->frame_pts_inc = 90000 / s->fps;
328
            debug_ipmovie("  %.2f frames/second (timer div = %d, subdiv = %d)\n",
329
                s->fps, LE_32(&scratch[0]), LE_16(&scratch[4]));
330
            break;
331

    
332
        case OPCODE_INIT_AUDIO_BUFFERS:
333
            debug_ipmovie("initialize audio buffers\n");
334
            if ((opcode_version > 1) || (opcode_size > 10)) {
335
                debug_ipmovie("bad init_audio_buffers opcode\n");
336
                chunk_type = CHUNK_BAD;
337
                break;
338
            }
339
            if (get_buffer(pb, scratch, opcode_size) !=
340
                opcode_size) {
341
                chunk_type = CHUNK_BAD;
342
                break;
343
            }
344
            s->audio_sample_rate = LE_16(&scratch[4]);
345
            audio_flags = LE_16(&scratch[2]);
346
            /* bit 0 of the flags: 0 = mono, 1 = stereo */
347
            s->audio_channels = (audio_flags & 1) + 1;
348
            /* bit 1 of the flags: 0 = 8 bit, 1 = 16 bit */
349
            s->audio_bits = (((audio_flags >> 1) & 1) + 1) * 8;
350
            /* bit 2 indicates compressed audio in version 1 opcode */
351
            if ((opcode_version == 1) && (audio_flags & 0x4))
352
                s->audio_type = CODEC_ID_INTERPLAY_DPCM;
353
            else if (s->audio_bits == 16)
354
                s->audio_type = CODEC_ID_PCM_S16LE;
355
            else
356
                s->audio_type = CODEC_ID_PCM_U8;
357
            debug_ipmovie("audio: %d bits, %d Hz, %s, %s format\n",
358
                s->audio_bits,
359
                s->audio_sample_rate,
360
                (s->audio_channels == 2) ? "stereo" : "mono",
361
                (s->audio_type == CODEC_ID_INTERPLAY_DPCM) ? 
362
                "Interplay audio" : "PCM");
363
            break;
364

    
365
        case OPCODE_START_STOP_AUDIO:
366
            debug_ipmovie("start/stop audio\n");
367
            url_fseek(pb, opcode_size, SEEK_CUR);
368
            break;
369

    
370
        case OPCODE_INIT_VIDEO_BUFFERS:
371
            debug_ipmovie("initialize video buffers\n");
372
            if ((opcode_version > 2) || (opcode_size > 8)) {
373
                debug_ipmovie("bad init_video_buffers opcode\n");
374
                chunk_type = CHUNK_BAD;
375
                break;
376
            }
377
            if (get_buffer(pb, scratch, opcode_size) !=
378
                opcode_size) {
379
                chunk_type = CHUNK_BAD;
380
                break;
381
            }
382
            s->video_width = LE_16(&scratch[0]) * 8;
383
            s->video_height = LE_16(&scratch[2]) * 8;
384
            debug_ipmovie("video resolution: %d x %d\n",
385
                s->video_width, s->video_height);
386
            break;
387

    
388
        case OPCODE_UNKNOWN_06:
389
        case OPCODE_UNKNOWN_0E:
390
        case OPCODE_UNKNOWN_10:
391
        case OPCODE_UNKNOWN_12:
392
        case OPCODE_UNKNOWN_13:
393
        case OPCODE_UNKNOWN_14:
394
        case OPCODE_UNKNOWN_15:
395
            debug_ipmovie("unknown (but documented) opcode %02X\n", opcode_type);
396
            url_fseek(pb, opcode_size, SEEK_CUR);
397
            break;
398

    
399
        case OPCODE_SEND_BUFFER:
400
            debug_ipmovie("send buffer\n");
401
            url_fseek(pb, opcode_size, SEEK_CUR);
402
            break;
403

    
404
        case OPCODE_AUDIO_FRAME:
405
            debug_ipmovie("audio frame\n");
406

    
407
            /* log position and move on for now */
408
            s->audio_chunk_offset = url_ftell(pb);
409
            s->audio_chunk_size = opcode_size;
410
            url_fseek(pb, opcode_size, SEEK_CUR);
411
            break;
412

    
413
        case OPCODE_SILENCE_FRAME:
414
            debug_ipmovie("silence frame\n");
415
            url_fseek(pb, opcode_size, SEEK_CUR);
416
            break;
417

    
418
        case OPCODE_INIT_VIDEO_MODE:
419
            debug_ipmovie("initialize video mode\n");
420
            url_fseek(pb, opcode_size, SEEK_CUR);
421
            break;
422

    
423
        case OPCODE_CREATE_GRADIENT:
424
            debug_ipmovie("create gradient\n");
425
            url_fseek(pb, opcode_size, SEEK_CUR);
426
            break;
427

    
428
        case OPCODE_SET_PALETTE:
429
            debug_ipmovie("set palette\n");
430
            /* check for the logical maximum palette size
431
             * (3 * 256 + 4 bytes) */
432
            if (opcode_size > 0x304) {
433
                debug_ipmovie("demux_ipmovie: set_palette opcode too large\n");
434
                chunk_type = CHUNK_BAD;
435
                break;
436
            }
437
            if (get_buffer(pb, scratch, opcode_size) != opcode_size) {
438
                chunk_type = CHUNK_BAD;
439
                break;
440
            }
441

    
442
            /* load the palette into internal data structure */
443
            first_color = LE_16(&scratch[0]);
444
            last_color = first_color + LE_16(&scratch[2]) - 1;
445
            /* sanity check (since they are 16 bit values) */
446
            if ((first_color > 0xFF) || (last_color > 0xFF)) {
447
                debug_ipmovie("demux_ipmovie: set_palette indices out of range (%d -> %d)\n",
448
                    first_color, last_color);
449
                chunk_type = CHUNK_BAD;
450
                break;
451
            }
452
            j = 4;  /* offset of first palette data */
453
            for (i = first_color; i <= last_color; i++) {
454
                /* the palette is stored as a 6-bit VGA palette, thus each
455
                 * component is shifted up to a 8-bit range */
456
                r = scratch[j++] * 4;
457
                g = scratch[j++] * 4;
458
                b = scratch[j++] * 4;
459
                s->palette_control.palette[i] = (r << 16) | (g << 8) | (b);
460
            }
461
            /* indicate a palette change */
462
            s->palette_control.palette_changed = 1;
463
            break;
464

    
465
        case OPCODE_SET_PALETTE_COMPRESSED:
466
            debug_ipmovie("set palette compressed\n");
467
            url_fseek(pb, opcode_size, SEEK_CUR);
468
            break;
469

    
470
        case OPCODE_SET_DECODING_MAP:
471
            debug_ipmovie("set decoding map\n");
472

    
473
            /* log position and move on for now */
474
            s->decode_map_chunk_offset = url_ftell(pb);
475
            s->decode_map_chunk_size = opcode_size;
476
            url_fseek(pb, opcode_size, SEEK_CUR);
477
            break;
478

    
479
        case OPCODE_VIDEO_DATA:
480
            debug_ipmovie("set video data\n");
481

    
482
            /* log position and move on for now */
483
            s->video_chunk_offset = url_ftell(pb);
484
            s->video_chunk_size = opcode_size;
485
            url_fseek(pb, opcode_size, SEEK_CUR);
486
            break;
487

    
488
        default:
489
            debug_ipmovie("*** unknown opcode type\n");
490
            chunk_type = CHUNK_BAD;
491
            break;
492

    
493
        }
494
    }
495

    
496
    /* make a note of where the stream is sitting */
497
    s->next_chunk_offset = url_ftell(pb);
498

    
499
    /* dispatch the first of any pending packets */
500
    if ((chunk_type == CHUNK_VIDEO) || (chunk_type == CHUNK_AUDIO_ONLY))
501
        chunk_type = load_ipmovie_packet(s, pb, pkt);
502

    
503
    return chunk_type;
504
}
505

    
506
static int ipmovie_probe(AVProbeData *p)
507
{
508
    if (p->buf_size < IPMOVIE_SIGNATURE_SIZE)
509
        return 0;
510
    if (strncmp(p->buf, IPMOVIE_SIGNATURE, IPMOVIE_SIGNATURE_SIZE) != 0)
511
        return 0;
512

    
513
    return AVPROBE_SCORE_MAX;
514
}
515

    
516
static int ipmovie_read_header(AVFormatContext *s,
517
                               AVFormatParameters *ap)
518
{
519
    IPMVEContext *ipmovie = (IPMVEContext *)s->priv_data;
520
    ByteIOContext *pb = &s->pb;
521
    AVPacket pkt;
522
    AVStream *st;
523
    unsigned char chunk_preamble[CHUNK_PREAMBLE_SIZE];
524
    int chunk_type;
525

    
526
    /* initialize private context members */
527
    ipmovie->video_pts = ipmovie->audio_frame_count = 0;
528
    ipmovie->audio_chunk_offset = ipmovie->video_chunk_offset =
529
    ipmovie->decode_map_chunk_offset = 0;
530

    
531
    /* on the first read, this will position the stream at the first chunk */
532
    ipmovie->next_chunk_offset = IPMOVIE_SIGNATURE_SIZE + 6;
533

    
534
    /* process the first chunk which should be CHUNK_INIT_VIDEO */
535
    if (process_ipmovie_chunk(ipmovie, pb, &pkt) != CHUNK_INIT_VIDEO)
536
        return AVERROR_INVALIDDATA;
537

    
538
    /* peek ahead to the next chunk-- if it is an init audio chunk, process
539
     * it; if it is the first video chunk, this is a silent file */
540
    if (get_buffer(pb, chunk_preamble, CHUNK_PREAMBLE_SIZE) !=
541
        CHUNK_PREAMBLE_SIZE)
542
        return AVERROR_IO;
543
    chunk_type = LE_16(&chunk_preamble[2]);
544
    url_fseek(pb, -CHUNK_PREAMBLE_SIZE, SEEK_CUR);
545

    
546
    if (chunk_type == CHUNK_VIDEO)
547
        ipmovie->audio_type = 0;  /* no audio */
548
    else if (process_ipmovie_chunk(ipmovie, pb, &pkt) != CHUNK_INIT_AUDIO)
549
        return AVERROR_INVALIDDATA;
550

    
551
    /* initialize the stream decoders */
552
    st = av_new_stream(s, 0);
553
    if (!st)
554
        return AVERROR_NOMEM;
555
    av_set_pts_info(st, 33, 1, 90000);
556
    ipmovie->video_stream_index = st->index;
557
    st->codec->codec_type = CODEC_TYPE_VIDEO;
558
    st->codec->codec_id = CODEC_ID_INTERPLAY_VIDEO;
559
    st->codec->codec_tag = 0;  /* no fourcc */
560
    st->codec->width = ipmovie->video_width;
561
    st->codec->height = ipmovie->video_height;
562

    
563
    /* palette considerations */
564
    st->codec->palctrl = &ipmovie->palette_control;
565

    
566
    if (ipmovie->audio_type) {
567
        st = av_new_stream(s, 0);
568
        if (!st)
569
            return AVERROR_NOMEM;
570
        av_set_pts_info(st, 33, 1, 90000);
571
        ipmovie->audio_stream_index = st->index;
572
        st->codec->codec_type = CODEC_TYPE_AUDIO;
573
        st->codec->codec_id = ipmovie->audio_type;
574
        st->codec->codec_tag = 0;  /* no tag */
575
        st->codec->channels = ipmovie->audio_channels;
576
        st->codec->sample_rate = ipmovie->audio_sample_rate;
577
        st->codec->bits_per_sample = ipmovie->audio_bits;
578
        st->codec->bit_rate = st->codec->channels * st->codec->sample_rate *
579
            st->codec->bits_per_sample;
580
        if (st->codec->codec_id == CODEC_ID_INTERPLAY_DPCM)
581
            st->codec->bit_rate /= 2;
582
        st->codec->block_align = st->codec->channels * st->codec->bits_per_sample;
583
    }
584

    
585
    return 0;
586
}
587

    
588
static int ipmovie_read_packet(AVFormatContext *s,
589
                               AVPacket *pkt)
590
{
591
    IPMVEContext *ipmovie = (IPMVEContext *)s->priv_data;
592
    ByteIOContext *pb = &s->pb;
593
    int ret;
594

    
595
    ret = process_ipmovie_chunk(ipmovie, pb, pkt);
596
    if (ret == CHUNK_BAD)
597
        ret = AVERROR_INVALIDDATA;
598
    else if (ret == CHUNK_EOF)
599
        ret = AVERROR_IO;
600
    else if (ret == CHUNK_NOMEM)
601
        ret = AVERROR_NOMEM;
602
    else
603
        ret = 0;
604

    
605
    return ret;
606
}
607

    
608
static int ipmovie_read_close(AVFormatContext *s)
609
{
610
//    IPMVEContext *ipmovie = (IPMVEContext *)s->priv_data;
611

    
612
    return 0;
613
}
614

    
615
static AVInputFormat ipmovie_iformat = {
616
    "ipmovie",
617
    "Interplay MVE format",
618
    sizeof(IPMVEContext),
619
    ipmovie_probe,
620
    ipmovie_read_header,
621
    ipmovie_read_packet,
622
    ipmovie_read_close,
623
};
624

    
625
int ipmovie_init(void)
626
{
627
    av_register_input_format(&ipmovie_iformat);
628
    return 0;
629
}
630