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1
/*
2
 * Duck TrueMotion 1.0 Decoder
3
 * Copyright (C) 2003 Alex Beregszaszi & Mike Melanson
4
 *
5
 * This library is free software; you can redistribute it and/or
6
 * modify it under the terms of the GNU Lesser General Public
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 * License as published by the Free Software Foundation; either
8
 * 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,
11
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
12
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
13
 * Lesser General Public License for more details.
14
 *
15
 * 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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 */
19

    
20
/**
21
 * @file truemotion1.c
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 * Duck TrueMotion v1 Video Decoder by 
23
 * Alex Beregszaszi (alex@fsn.hu) and
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 * Mike Melanson (melanson@pcisys.net)
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 *
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 * The TrueMotion v1 decoder presently only decodes 16-bit TM1 data and
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 * outputs RGB555 data. 24-bit TM1 data is not supported yet.
28
 */
29

    
30
#include <stdio.h>
31
#include <stdlib.h>
32
#include <string.h>
33
#include <unistd.h>
34

    
35
#include "common.h"
36
#include "avcodec.h"
37
#include "dsputil.h"
38

    
39
#include "truemotion1data.h"
40

    
41
typedef struct TrueMotion1Context {
42
    AVCodecContext *avctx;
43
    AVFrame frame;
44
    AVFrame prev_frame;
45

    
46
    unsigned char *buf;
47
    int size;
48

    
49
    unsigned char *mb_change_bits;
50
    int mb_change_bits_row_size;
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    unsigned char *index_stream;
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    int index_stream_size;
53

    
54
    int flags;
55
    int x, y, w, h;
56
    
57
    uint32_t y_predictor_table[1024];
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    uint32_t c_predictor_table[1024];
59
    
60
    int compression;
61
    int block_type;
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    int block_width;
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    int block_height;
64

    
65
    int16_t *ydt;
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    int16_t *cdt;
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    int16_t *fat_ydt;
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    int16_t *fat_cdt;
69
    
70
    int last_deltaset, last_vectable;
71

    
72
    unsigned int *vert_pred;
73

    
74
} TrueMotion1Context;
75

    
76
#define FLAG_SPRITE         32
77
#define FLAG_KEYFRAME       16
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#define FLAG_INTERFRAME      8
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#define FLAG_INTERPOLATED    4
80

    
81
struct frame_header {
82
    uint8_t header_size;
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    uint8_t compression;
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    uint8_t deltaset;
85
    uint8_t vectable;
86
    uint16_t ysize;
87
    uint16_t xsize;
88
    uint16_t checksum;
89
    uint8_t version;
90
    uint8_t header_type;
91
    uint8_t flags;
92
    uint8_t control;
93
    uint16_t xoffset;
94
    uint16_t yoffset;
95
    uint16_t width;
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    uint16_t height;
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};
98

    
99
#define ALGO_NOP        0
100
#define ALGO_RGB16V     1
101
#define ALGO_RGB16H     2
102
#define ALGO_RGB24H     3
103

    
104
/* these are the various block sizes that can occupy a 4x4 block */
105
#define BLOCK_2x2  0
106
#define BLOCK_2x4  1
107
#define BLOCK_4x2  2
108
#define BLOCK_4x4  3
109

    
110
typedef struct comp_types {
111
    int algorithm;
112
    int block_width;
113
    int block_height;
114
    int block_type;
115
} comp_types;
116

    
117
/* { valid for metatype }, algorithm, num of deltas, horiz res, vert res */
118
static comp_types compression_types[17] = {
119
    { ALGO_NOP,    0, 0, 0 },
120

    
121
    { ALGO_RGB16V, 4, 4, BLOCK_4x4 },
122
    { ALGO_RGB16H, 4, 4, BLOCK_4x4 },
123
    { ALGO_RGB16V, 4, 2, BLOCK_4x2 },
124
    { ALGO_RGB16H, 4, 2, BLOCK_4x2 },
125

    
126
    { ALGO_RGB16V, 2, 4, BLOCK_2x4 },
127
    { ALGO_RGB16H, 2, 4, BLOCK_2x4 },
128
    { ALGO_RGB16V, 2, 2, BLOCK_2x2 },
129
    { ALGO_RGB16H, 2, 2, BLOCK_2x2 },
130

    
131
    { ALGO_NOP,    4, 4, BLOCK_4x4 },
132
    { ALGO_RGB24H, 4, 4, BLOCK_4x4 },
133
    { ALGO_NOP,    4, 2, BLOCK_4x2 },
134
    { ALGO_RGB24H, 4, 2, BLOCK_4x2 },
135

    
136
    { ALGO_NOP,    2, 4, BLOCK_2x4 },
137
    { ALGO_RGB24H, 2, 4, BLOCK_2x4 },
138
    { ALGO_NOP,    2, 2, BLOCK_2x2 },
139
    { ALGO_RGB24H, 2, 2, BLOCK_2x2 }
140
};
141

    
142
static void select_delta_tables(TrueMotion1Context *s, int delta_table_index)
143
{
144
    int i;
145

    
146
    if (delta_table_index > 3)
147
        return;
148

    
149
    s->ydt = ydts[delta_table_index];
150
    s->cdt = cdts[delta_table_index];
151
    s->fat_ydt = fat_ydts[delta_table_index];
152
    s->fat_cdt = fat_cdts[delta_table_index];
153

    
154
    /* Y skinny deltas need to be halved for some reason; maybe the
155
     * skinny Y deltas should be modified */
156
    for (i = 0; i < 8; i++)
157
    {
158
        /* drop the lsb before dividing by 2-- net effect: round down
159
         * when dividing a negative number (e.g., -3/2 = -2, not -1) */
160
        s->ydt[i] &= 0xFFFE;
161
        s->ydt[i] /= 2;
162
    }
163
}
164

    
165
#ifdef WORDS_BIGENDIAN
166
static int make_ydt_entry(int p2, int p1, int16_t *ydt)
167
#else
168
static int make_ydt_entry(int p1, int p2, int16_t *ydt)
169
#endif
170
{
171
    int lo, hi;
172
    
173
    lo = ydt[p1];
174
    lo += (lo << 5) + (lo << 10);
175
    hi = ydt[p2];
176
    hi += (hi << 5) + (hi << 10);
177
    return ((lo + (hi << 16)) << 1);
178
}
179

    
180
#ifdef WORDS_BIGENDIAN
181
static int make_cdt_entry(int p2, int p1, int16_t *cdt)
182
#else
183
static int make_cdt_entry(int p1, int p2, int16_t *cdt)
184
#endif
185
{
186
    int r, b, lo;
187
    
188
    b = cdt[p2];
189
    r = cdt[p1] << 10;
190
    lo = b + r;
191
    return ((lo + (lo << 16)) << 1);
192
}
193

    
194
static void gen_vector_table(TrueMotion1Context *s, uint8_t *sel_vector_table)
195
{
196
    int len, i, j;
197
    unsigned char delta_pair;
198
    
199
    for (i = 0; i < 1024; i += 4)
200
    {
201
        len = *sel_vector_table++ / 2;
202
        for (j = 0; j < len; j++)
203
        {
204
            delta_pair = *sel_vector_table++;
205
            s->y_predictor_table[i+j] = 0xfffffffe & 
206
                make_ydt_entry(delta_pair >> 4, delta_pair & 0xf, s->ydt);
207
            s->c_predictor_table[i+j] = 0xfffffffe & 
208
                make_cdt_entry(delta_pair >> 4, delta_pair & 0xf, s->cdt);
209
        }
210
        s->y_predictor_table[i+(j-1)] |= 1;
211
        s->c_predictor_table[i+(j-1)] |= 1;
212
    }
213
}
214

    
215
/* Returns the number of bytes consumed from the bytestream. Returns -1 if
216
 * there was an error while decoding the header */ 
217
static int truemotion1_decode_header(TrueMotion1Context *s)
218
{
219
    int i;
220
    struct frame_header header;
221
    uint8_t header_buffer[128];  /* logical maximum size of the header */
222
    uint8_t *sel_vector_table;
223

    
224
    /* There is 1 change bit per 4 pixels, so each change byte represents
225
     * 32 pixels; divide width by 4 to obtain the number of change bits and
226
     * then round up to the nearest byte. */
227
    s->mb_change_bits_row_size = ((s->avctx->width >> 2) + 7) >> 3;
228

    
229
    header.header_size = ((s->buf[0] >> 5) | (s->buf[0] << 3)) & 0x7f;
230
    if (s->buf[0] < 0x10)
231
    {
232
        av_log(s->avctx, AV_LOG_ERROR, "invalid header size\n");
233
        return -1;
234
    }
235

    
236
    /* unscramble the header bytes with a XOR operation */
237
    memset(header_buffer, 0, 128);
238
    for (i = 1; i < header.header_size; i++)
239
    header_buffer[i - 1] = s->buf[i] ^ s->buf[i + 1];
240
    header.compression = header_buffer[0];
241
    header.deltaset = header_buffer[1];
242
    header.vectable = header_buffer[2];
243
    header.ysize = LE_16(&header_buffer[3]);
244
    header.xsize = LE_16(&header_buffer[5]);
245
    header.checksum = LE_16(&header_buffer[7]);
246
    header.version = header_buffer[9];
247
    header.header_type = header_buffer[10];
248
    header.flags = header_buffer[11];
249
    header.control = header_buffer[12];
250

    
251
    /* Version 2 */
252
    if (header.version >= 2)
253
    {
254
        if (header.header_type > 3)
255
        {
256
            av_log(s->avctx, AV_LOG_ERROR, "truemotion1: invalid header type\n");
257
            return -1;
258
        } else if ((header.header_type == 2) || (header.header_type == 3)) {
259
            s->flags = header.flags;
260
            if (!(s->flags & FLAG_INTERFRAME))
261
                s->flags |= FLAG_KEYFRAME;
262
        } else
263
            s->flags = FLAG_KEYFRAME;
264
    } else /* Version 1 */
265
        s->flags = FLAG_KEYFRAME;
266
    
267
    if (s->flags & FLAG_SPRITE) {
268
        s->w = header.width;
269
        s->h = header.height;
270
        s->x = header.xoffset;
271
        s->y = header.yoffset;
272
    } else {
273
        s->w = header.xsize;
274
        s->h = header.ysize;
275
        if (header.header_type < 2) {
276
            if ((s->w < 213) && (s->h >= 176))
277
                s->flags |= FLAG_INTERPOLATED;
278
        }
279
    }
280

    
281
    if (header.compression > 17) {
282
        av_log(s->avctx, AV_LOG_ERROR, "invalid compression type (%d)\n", header.compression);
283
        return -1;
284
    }
285
    
286
    if ((header.deltaset != s->last_deltaset) || 
287
        (header.vectable != s->last_vectable))
288
        select_delta_tables(s, header.deltaset);
289

    
290
    if ((header.compression & 1) && header.header_type)
291
        sel_vector_table = pc_tbl2;
292
    else {
293
        if (header.vectable < 4)
294
            sel_vector_table = tables[header.vectable - 1];
295
        else {
296
            av_log(s->avctx, AV_LOG_ERROR, "invalid vector table id (%d)\n", header.vectable);
297
            return -1;
298
        }
299
    }
300

    
301
    if ((header.deltaset != s->last_deltaset) || (header.vectable != s->last_vectable))
302
    {
303
        if (compression_types[header.compression].algorithm == ALGO_RGB24H)
304
        {
305
            av_log(s->avctx, AV_LOG_ERROR, "24bit compression not yet supported\n");
306
        }
307
        else
308
            gen_vector_table(s, sel_vector_table);
309
    }
310

    
311
    /* set up pointers to the other key data chunks */
312
    s->mb_change_bits = s->buf + header.header_size;
313
    if (s->flags & FLAG_KEYFRAME) {
314
        /* no change bits specified for a keyframe; only index bytes */
315
        s->index_stream = s->mb_change_bits;
316
    } else {
317
        /* one change bit per 4x4 block */
318
        s->index_stream = s->mb_change_bits + 
319
            (s->mb_change_bits_row_size * (s->avctx->height >> 2));
320
    }
321
    s->index_stream_size = s->size - (s->index_stream - s->buf);
322

    
323
    s->last_deltaset = header.deltaset;
324
    s->last_vectable = header.vectable;
325
    s->compression = header.compression;
326
    s->block_width = compression_types[header.compression].block_width;
327
    s->block_height = compression_types[header.compression].block_height;
328
    s->block_type = compression_types[header.compression].block_type;
329

    
330
    return header.header_size;    
331
}
332

    
333
static int truemotion1_decode_init(AVCodecContext *avctx)
334
{
335
    TrueMotion1Context *s = (TrueMotion1Context *)avctx->priv_data;
336

    
337
    s->avctx = avctx;
338

    
339
    avctx->pix_fmt = PIX_FMT_RGB555;
340
    avctx->has_b_frames = 0;
341
    s->frame.data[0] = s->prev_frame.data[0] = NULL;
342

    
343
    /* there is a vertical predictor for each pixel in a line; each vertical
344
     * predictor is 0 to start with */
345
    s->vert_pred = 
346
        (unsigned int *)av_malloc(s->avctx->width * sizeof(unsigned short));
347

    
348
    return 0;
349
}
350

    
351
#define GET_NEXT_INDEX() \
352
{\
353
    if (index_stream_index >= s->index_stream_size) { \
354
        av_log(s->avctx, AV_LOG_INFO, " help! truemotion1 decoder went out of bounds\n"); \
355
        return; \
356
    } \
357
    index = s->index_stream[index_stream_index++] * 4; \
358
}
359

    
360
#define APPLY_C_PREDICTOR() \
361
    predictor_pair = s->c_predictor_table[index]; \
362
    horiz_pred += (predictor_pair >> 1); \
363
    if (predictor_pair & 1) { \
364
        GET_NEXT_INDEX() \
365
        if (!index) { \
366
            GET_NEXT_INDEX() \
367
            predictor_pair = s->c_predictor_table[index]; \
368
            horiz_pred += ((predictor_pair >> 1) * 5); \
369
            if (predictor_pair & 1) \
370
                GET_NEXT_INDEX() \
371
            else \
372
                index++; \
373
        } \
374
    } else \
375
        index++;
376

    
377
#define APPLY_Y_PREDICTOR() \
378
    predictor_pair = s->y_predictor_table[index]; \
379
    horiz_pred += (predictor_pair >> 1); \
380
    if (predictor_pair & 1) { \
381
        GET_NEXT_INDEX() \
382
        if (!index) { \
383
            GET_NEXT_INDEX() \
384
            predictor_pair = s->y_predictor_table[index]; \
385
            horiz_pred += ((predictor_pair >> 1) * 5); \
386
            if (predictor_pair & 1) \
387
                GET_NEXT_INDEX() \
388
            else \
389
                index++; \
390
        } \
391
    } else \
392
        index++;
393

    
394
#define OUTPUT_PIXEL_PAIR() \
395
    *current_pixel_pair = *vert_pred + horiz_pred; \
396
    *vert_pred++ = *current_pixel_pair++; \
397
    prev_pixel_pair++;
398

    
399
static void truemotion1_decode_16bit(TrueMotion1Context *s)
400
{
401
    int y;
402
    int pixels_left;  /* remaining pixels on this line */
403
    unsigned int predictor_pair;
404
    unsigned int horiz_pred;
405
    unsigned int *vert_pred;
406
    unsigned int *current_pixel_pair;
407
    unsigned int *prev_pixel_pair;
408
    unsigned char *current_line = s->frame.data[0];
409
    unsigned char *prev_line = s->prev_frame.data[0];
410
    int keyframe = s->flags & FLAG_KEYFRAME;
411

    
412
    /* these variables are for managing the stream of macroblock change bits */
413
    unsigned char *mb_change_bits = s->mb_change_bits;
414
    unsigned char mb_change_byte;
415
    unsigned char mb_change_byte_mask;
416
    int mb_change_index;
417

    
418
    /* these variables are for managing the main index stream */
419
    int index_stream_index = 0;  /* yes, the index into the index stream */
420
    int index;
421

    
422
    /* clean out the line buffer */
423
    memset(s->vert_pred, 0, s->avctx->width * sizeof(unsigned short));
424

    
425
    GET_NEXT_INDEX();
426

    
427
    for (y = 0; y < s->avctx->height; y++) {
428

    
429
        /* re-init variables for the next line iteration */
430
        horiz_pred = 0;
431
        current_pixel_pair = (unsigned int *)current_line;
432
        prev_pixel_pair = (unsigned int *)prev_line;
433
        vert_pred = s->vert_pred;
434
        mb_change_index = 0;
435
        mb_change_byte = mb_change_bits[mb_change_index++];
436
        mb_change_byte_mask = 0x01;
437
        pixels_left = s->avctx->width;
438

    
439
        while (pixels_left > 0) {
440

    
441
            if (keyframe || ((mb_change_byte & mb_change_byte_mask) == 0)) {
442

    
443
                switch (y & 3) {
444
                case 0:
445
                    /* if macroblock width is 2, apply C-Y-C-Y; else 
446
                     * apply C-Y-Y */
447
                    if (s->block_width == 2) {
448
                        APPLY_C_PREDICTOR();
449
                        APPLY_Y_PREDICTOR();
450
                        OUTPUT_PIXEL_PAIR();
451
                        APPLY_C_PREDICTOR();
452
                        APPLY_Y_PREDICTOR();
453
                        OUTPUT_PIXEL_PAIR();
454
                    } else {
455
                        APPLY_C_PREDICTOR();
456
                        APPLY_Y_PREDICTOR();
457
                        OUTPUT_PIXEL_PAIR();
458
                        APPLY_Y_PREDICTOR();
459
                        OUTPUT_PIXEL_PAIR();
460
                    }
461
                    break;
462

    
463
                case 1:
464
                case 3:
465
                    /* always apply 2 Y predictors on these iterations */
466
                    APPLY_Y_PREDICTOR();
467
                    OUTPUT_PIXEL_PAIR();
468
                    APPLY_Y_PREDICTOR();
469
                    OUTPUT_PIXEL_PAIR();
470
                    break;
471

    
472
                case 2:
473
                    /* this iteration might be C-Y-C-Y, Y-Y, or C-Y-Y 
474
                     * depending on the macroblock type */
475
                    if (s->block_type == BLOCK_2x2) {
476
                        APPLY_C_PREDICTOR();
477
                        APPLY_Y_PREDICTOR();
478
                        OUTPUT_PIXEL_PAIR();
479
                        APPLY_C_PREDICTOR();
480
                        APPLY_Y_PREDICTOR();
481
                        OUTPUT_PIXEL_PAIR();
482
                    } else if (s->block_type == BLOCK_4x2) {
483
                        APPLY_C_PREDICTOR();
484
                        APPLY_Y_PREDICTOR();
485
                        OUTPUT_PIXEL_PAIR();
486
                        APPLY_Y_PREDICTOR();
487
                        OUTPUT_PIXEL_PAIR();
488
                    } else {
489
                        APPLY_Y_PREDICTOR();
490
                        OUTPUT_PIXEL_PAIR();
491
                        APPLY_Y_PREDICTOR();
492
                        OUTPUT_PIXEL_PAIR();
493
                    }
494
                    break;
495
                }
496

    
497
            } else {
498

    
499
                /* skip (copy) four pixels, but reassign the horizontal 
500
                 * predictor */
501
                *current_pixel_pair = *prev_pixel_pair++;
502
                *vert_pred++ = *current_pixel_pair++;
503
                *current_pixel_pair = *prev_pixel_pair++;
504
                horiz_pred = *current_pixel_pair - *vert_pred;
505
                *vert_pred++ = *current_pixel_pair++;
506
                
507
            }
508

    
509
            if (!keyframe) {
510
                mb_change_byte_mask <<= 1;
511

    
512
                /* next byte */
513
                if (!mb_change_byte_mask) {
514
                    mb_change_byte = mb_change_bits[mb_change_index++];
515
                    mb_change_byte_mask = 0x01;
516
                }
517
            }
518

    
519
            pixels_left -= 4;
520
        }
521

    
522
        /* next change row */
523
        if (((y + 1) & 3) == 0)
524
            mb_change_bits += s->mb_change_bits_row_size;
525

    
526
        current_line += s->frame.linesize[0];
527
        prev_line += s->prev_frame.linesize[0];
528
    }
529
}
530

    
531
static int truemotion1_decode_frame(AVCodecContext *avctx,
532
                                    void *data, int *data_size,
533
                                    uint8_t *buf, int buf_size)
534
{
535
    TrueMotion1Context *s = (TrueMotion1Context *)avctx->priv_data;
536

    
537
    s->buf = buf;
538
    s->size = buf_size;
539

    
540
    s->frame.reference = 1;
541
    if (avctx->get_buffer(avctx, &s->frame) < 0) {
542
        av_log(s->avctx, AV_LOG_ERROR, "truemotion1: get_buffer() failed\n");
543
        return -1;
544
    }
545

    
546
    /* no supplementary picture */
547
    if (buf_size == 0)
548
        return 0;
549

    
550
    *data_size = 0;
551
    
552
    if (truemotion1_decode_header(s) == -1)
553
        return -1;
554

    
555
    /* check for a do-nothing frame and copy the previous frame */
556
    if (compression_types[s->compression].algorithm == ALGO_NOP)
557
    {
558
        memcpy(s->frame.data[0], s->prev_frame.data[0],
559
            s->frame.linesize[0] * s->avctx->height);
560
    } else if (compression_types[s->compression].algorithm == ALGO_RGB24H) {
561
        av_log(s->avctx, AV_LOG_ERROR, "24bit compression not yet supported\n");
562
    } else {
563
        truemotion1_decode_16bit(s);
564
    }
565

    
566
    if (s->prev_frame.data[0])
567
        avctx->release_buffer(avctx, &s->prev_frame);
568

    
569
    /* shuffle frames */
570
    s->prev_frame = s->frame;
571

    
572
    *data_size = sizeof(AVFrame);
573
    *(AVFrame*)data = s->frame;
574

    
575
    /* report that the buffer was completely consumed */
576
    return buf_size;
577
}
578

    
579
static int truemotion1_decode_end(AVCodecContext *avctx)
580
{
581
    TrueMotion1Context *s = (TrueMotion1Context *)avctx->priv_data;
582

    
583
    /* release the last frame */
584
    if (s->prev_frame.data[0])
585
        avctx->release_buffer(avctx, &s->prev_frame);
586

    
587
    av_free(s->vert_pred);
588

    
589
    return 0;
590
}
591

    
592
AVCodec truemotion1_decoder = {
593
    "truemotion1",
594
    CODEC_TYPE_VIDEO,
595
    CODEC_ID_TRUEMOTION1,
596
    sizeof(TrueMotion1Context),
597
    truemotion1_decode_init,
598
    NULL,
599
    truemotion1_decode_end,
600
    truemotion1_decode_frame,
601
    CODEC_CAP_DR1,
602
};