truemotion1.c
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1 /*
2  * Duck TrueMotion 1.0 Decoder
3  * Copyright (C) 2003 Alex Beregszaszi & Mike Melanson
4  *
5  * This file is part of Libav.
6  *
7  * Libav 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  * Libav 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 Libav; if not, write to the Free Software
19  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
20  */
21 
32 #include <stdio.h>
33 #include <stdlib.h>
34 #include <string.h>
35 
36 #include "avcodec.h"
37 #include "dsputil.h"
38 #include "libavutil/imgutils.h"
39 
40 #include "truemotion1data.h"
41 
42 typedef struct TrueMotion1Context {
45 
46  const uint8_t *buf;
47  int size;
48 
49  const uint8_t *mb_change_bits;
51  const uint8_t *index_stream;
53 
54  int flags;
55  int x, y, w, h;
56 
57  uint32_t y_predictor_table[1024];
58  uint32_t c_predictor_table[1024];
59  uint32_t fat_y_predictor_table[1024];
60  uint32_t fat_c_predictor_table[1024];
61 
66 
67  int16_t ydt[8];
68  int16_t cdt[8];
69  int16_t fat_ydt[8];
70  int16_t fat_cdt[8];
71 
73 
74  unsigned int *vert_pred;
76 
78 
79 #define FLAG_SPRITE 32
80 #define FLAG_KEYFRAME 16
81 #define FLAG_INTERFRAME 8
82 #define FLAG_INTERPOLATED 4
83 
84 struct frame_header {
85  uint8_t header_size;
86  uint8_t compression;
87  uint8_t deltaset;
88  uint8_t vectable;
89  uint16_t ysize;
90  uint16_t xsize;
91  uint16_t checksum;
92  uint8_t version;
93  uint8_t header_type;
94  uint8_t flags;
95  uint8_t control;
96  uint16_t xoffset;
97  uint16_t yoffset;
98  uint16_t width;
99  uint16_t height;
100 };
101 
102 #define ALGO_NOP 0
103 #define ALGO_RGB16V 1
104 #define ALGO_RGB16H 2
105 #define ALGO_RGB24H 3
106 
107 /* these are the various block sizes that can occupy a 4x4 block */
108 #define BLOCK_2x2 0
109 #define BLOCK_2x4 1
110 #define BLOCK_4x2 2
111 #define BLOCK_4x4 3
112 
113 typedef struct comp_types {
115  int block_width; // vres
116  int block_height; // hres
118 } comp_types;
119 
120 /* { valid for metatype }, algorithm, num of deltas, vert res, horiz res */
121 static const comp_types compression_types[17] = {
122  { ALGO_NOP, 0, 0, 0 },
123 
124  { ALGO_RGB16V, 4, 4, BLOCK_4x4 },
125  { ALGO_RGB16H, 4, 4, BLOCK_4x4 },
126  { ALGO_RGB16V, 4, 2, BLOCK_4x2 },
127  { ALGO_RGB16H, 4, 2, BLOCK_4x2 },
128 
129  { ALGO_RGB16V, 2, 4, BLOCK_2x4 },
130  { ALGO_RGB16H, 2, 4, BLOCK_2x4 },
131  { ALGO_RGB16V, 2, 2, BLOCK_2x2 },
132  { ALGO_RGB16H, 2, 2, BLOCK_2x2 },
133 
134  { ALGO_NOP, 4, 4, BLOCK_4x4 },
135  { ALGO_RGB24H, 4, 4, BLOCK_4x4 },
136  { ALGO_NOP, 4, 2, BLOCK_4x2 },
137  { ALGO_RGB24H, 4, 2, BLOCK_4x2 },
138 
139  { ALGO_NOP, 2, 4, BLOCK_2x4 },
140  { ALGO_RGB24H, 2, 4, BLOCK_2x4 },
141  { ALGO_NOP, 2, 2, BLOCK_2x2 },
142  { ALGO_RGB24H, 2, 2, BLOCK_2x2 }
143 };
144 
145 static void select_delta_tables(TrueMotion1Context *s, int delta_table_index)
146 {
147  int i;
148 
149  if (delta_table_index > 3)
150  return;
151 
152  memcpy(s->ydt, ydts[delta_table_index], 8 * sizeof(int16_t));
153  memcpy(s->cdt, cdts[delta_table_index], 8 * sizeof(int16_t));
154  memcpy(s->fat_ydt, fat_ydts[delta_table_index], 8 * sizeof(int16_t));
155  memcpy(s->fat_cdt, fat_cdts[delta_table_index], 8 * sizeof(int16_t));
156 
157  /* Y skinny deltas need to be halved for some reason; maybe the
158  * skinny Y deltas should be modified */
159  for (i = 0; i < 8; i++)
160  {
161  /* drop the lsb before dividing by 2-- net effect: round down
162  * when dividing a negative number (e.g., -3/2 = -2, not -1) */
163  s->ydt[i] &= 0xFFFE;
164  s->ydt[i] /= 2;
165  }
166 }
167 
168 #if HAVE_BIGENDIAN
169 static int make_ydt15_entry(int p2, int p1, int16_t *ydt)
170 #else
171 static int make_ydt15_entry(int p1, int p2, int16_t *ydt)
172 #endif
173 {
174  int lo, hi;
175 
176  lo = ydt[p1];
177  lo += (lo << 5) + (lo << 10);
178  hi = ydt[p2];
179  hi += (hi << 5) + (hi << 10);
180  return (lo + (hi << 16)) << 1;
181 }
182 
183 static int make_cdt15_entry(int p1, int p2, int16_t *cdt)
184 {
185  int r, b, lo;
186 
187  b = cdt[p2];
188  r = cdt[p1] << 10;
189  lo = b + r;
190  return (lo + (lo << 16)) << 1;
191 }
192 
193 #if HAVE_BIGENDIAN
194 static int make_ydt16_entry(int p2, int p1, int16_t *ydt)
195 #else
196 static int make_ydt16_entry(int p1, int p2, int16_t *ydt)
197 #endif
198 {
199  int lo, hi;
200 
201  lo = ydt[p1];
202  lo += (lo << 6) + (lo << 11);
203  hi = ydt[p2];
204  hi += (hi << 6) + (hi << 11);
205  return (lo + (hi << 16)) << 1;
206 }
207 
208 static int make_cdt16_entry(int p1, int p2, int16_t *cdt)
209 {
210  int r, b, lo;
211 
212  b = cdt[p2];
213  r = cdt[p1] << 11;
214  lo = b + r;
215  return (lo + (lo << 16)) << 1;
216 }
217 
218 static int make_ydt24_entry(int p1, int p2, int16_t *ydt)
219 {
220  int lo, hi;
221 
222  lo = ydt[p1];
223  hi = ydt[p2];
224  return (lo + (hi << 8) + (hi << 16)) << 1;
225 }
226 
227 static int make_cdt24_entry(int p1, int p2, int16_t *cdt)
228 {
229  int r, b;
230 
231  b = cdt[p2];
232  r = cdt[p1]<<16;
233  return (b+r) << 1;
234 }
235 
236 static void gen_vector_table15(TrueMotion1Context *s, const uint8_t *sel_vector_table)
237 {
238  int len, i, j;
239  unsigned char delta_pair;
240 
241  for (i = 0; i < 1024; i += 4)
242  {
243  len = *sel_vector_table++ / 2;
244  for (j = 0; j < len; j++)
245  {
246  delta_pair = *sel_vector_table++;
247  s->y_predictor_table[i+j] = 0xfffffffe &
248  make_ydt15_entry(delta_pair >> 4, delta_pair & 0xf, s->ydt);
249  s->c_predictor_table[i+j] = 0xfffffffe &
250  make_cdt15_entry(delta_pair >> 4, delta_pair & 0xf, s->cdt);
251  }
252  s->y_predictor_table[i+(j-1)] |= 1;
253  s->c_predictor_table[i+(j-1)] |= 1;
254  }
255 }
256 
257 static void gen_vector_table16(TrueMotion1Context *s, const uint8_t *sel_vector_table)
258 {
259  int len, i, j;
260  unsigned char delta_pair;
261 
262  for (i = 0; i < 1024; i += 4)
263  {
264  len = *sel_vector_table++ / 2;
265  for (j = 0; j < len; j++)
266  {
267  delta_pair = *sel_vector_table++;
268  s->y_predictor_table[i+j] = 0xfffffffe &
269  make_ydt16_entry(delta_pair >> 4, delta_pair & 0xf, s->ydt);
270  s->c_predictor_table[i+j] = 0xfffffffe &
271  make_cdt16_entry(delta_pair >> 4, delta_pair & 0xf, s->cdt);
272  }
273  s->y_predictor_table[i+(j-1)] |= 1;
274  s->c_predictor_table[i+(j-1)] |= 1;
275  }
276 }
277 
278 static void gen_vector_table24(TrueMotion1Context *s, const uint8_t *sel_vector_table)
279 {
280  int len, i, j;
281  unsigned char delta_pair;
282 
283  for (i = 0; i < 1024; i += 4)
284  {
285  len = *sel_vector_table++ / 2;
286  for (j = 0; j < len; j++)
287  {
288  delta_pair = *sel_vector_table++;
289  s->y_predictor_table[i+j] = 0xfffffffe &
290  make_ydt24_entry(delta_pair >> 4, delta_pair & 0xf, s->ydt);
291  s->c_predictor_table[i+j] = 0xfffffffe &
292  make_cdt24_entry(delta_pair >> 4, delta_pair & 0xf, s->cdt);
293  s->fat_y_predictor_table[i+j] = 0xfffffffe &
294  make_ydt24_entry(delta_pair >> 4, delta_pair & 0xf, s->fat_ydt);
295  s->fat_c_predictor_table[i+j] = 0xfffffffe &
296  make_cdt24_entry(delta_pair >> 4, delta_pair & 0xf, s->fat_cdt);
297  }
298  s->y_predictor_table[i+(j-1)] |= 1;
299  s->c_predictor_table[i+(j-1)] |= 1;
300  s->fat_y_predictor_table[i+(j-1)] |= 1;
301  s->fat_c_predictor_table[i+(j-1)] |= 1;
302  }
303 }
304 
305 /* Returns the number of bytes consumed from the bytestream. Returns -1 if
306  * there was an error while decoding the header */
308 {
309  int i;
310  int width_shift = 0;
311  int new_pix_fmt;
312  struct frame_header header;
313  uint8_t header_buffer[128]; /* logical maximum size of the header */
314  const uint8_t *sel_vector_table;
315 
316  header.header_size = ((s->buf[0] >> 5) | (s->buf[0] << 3)) & 0x7f;
317  if (s->buf[0] < 0x10)
318  {
319  av_log(s->avctx, AV_LOG_ERROR, "invalid header size (%d)\n", s->buf[0]);
320  return -1;
321  }
322 
323  /* unscramble the header bytes with a XOR operation */
324  memset(header_buffer, 0, 128);
325  for (i = 1; i < header.header_size; i++)
326  header_buffer[i - 1] = s->buf[i] ^ s->buf[i + 1];
327 
328  header.compression = header_buffer[0];
329  header.deltaset = header_buffer[1];
330  header.vectable = header_buffer[2];
331  header.ysize = AV_RL16(&header_buffer[3]);
332  header.xsize = AV_RL16(&header_buffer[5]);
333  header.checksum = AV_RL16(&header_buffer[7]);
334  header.version = header_buffer[9];
335  header.header_type = header_buffer[10];
336  header.flags = header_buffer[11];
337  header.control = header_buffer[12];
338 
339  /* Version 2 */
340  if (header.version >= 2)
341  {
342  if (header.header_type > 3)
343  {
344  av_log(s->avctx, AV_LOG_ERROR, "invalid header type (%d)\n", header.header_type);
345  return -1;
346  } else if ((header.header_type == 2) || (header.header_type == 3)) {
347  s->flags = header.flags;
348  if (!(s->flags & FLAG_INTERFRAME))
349  s->flags |= FLAG_KEYFRAME;
350  } else
351  s->flags = FLAG_KEYFRAME;
352  } else /* Version 1 */
353  s->flags = FLAG_KEYFRAME;
354 
355  if (s->flags & FLAG_SPRITE) {
356  av_log_ask_for_sample(s->avctx, "SPRITE frame found.\n");
357  /* FIXME header.width, height, xoffset and yoffset aren't initialized */
358 #if 0
359  s->w = header.width;
360  s->h = header.height;
361  s->x = header.xoffset;
362  s->y = header.yoffset;
363 #else
364  return -1;
365 #endif
366  } else {
367  s->w = header.xsize;
368  s->h = header.ysize;
369  if (header.header_type < 2) {
370  if ((s->w < 213) && (s->h >= 176))
371  {
372  s->flags |= FLAG_INTERPOLATED;
373  av_log_ask_for_sample(s->avctx, "INTERPOLATION selected.\n");
374  }
375  }
376  }
377 
378  if (header.compression >= 17) {
379  av_log(s->avctx, AV_LOG_ERROR, "invalid compression type (%d)\n", header.compression);
380  return -1;
381  }
382 
383  if ((header.deltaset != s->last_deltaset) ||
384  (header.vectable != s->last_vectable))
385  select_delta_tables(s, header.deltaset);
386 
387  if ((header.compression & 1) && header.header_type)
388  sel_vector_table = pc_tbl2;
389  else {
390  if (header.vectable > 0 && header.vectable < 4)
391  sel_vector_table = tables[header.vectable - 1];
392  else {
393  av_log(s->avctx, AV_LOG_ERROR, "invalid vector table id (%d)\n", header.vectable);
394  return -1;
395  }
396  }
397 
398  if (compression_types[header.compression].algorithm == ALGO_RGB24H) {
399  new_pix_fmt = PIX_FMT_RGB32;
400  width_shift = 1;
401  } else
402  new_pix_fmt = PIX_FMT_RGB555; // RGB565 is supported as well
403 
404  s->w >>= width_shift;
405  if (av_image_check_size(s->w, s->h, 0, s->avctx) < 0)
406  return -1;
407 
408  if (s->w != s->avctx->width || s->h != s->avctx->height ||
409  new_pix_fmt != s->avctx->pix_fmt) {
410  if (s->frame.data[0])
411  s->avctx->release_buffer(s->avctx, &s->frame);
412  s->avctx->sample_aspect_ratio = (AVRational){ 1 << width_shift, 1 };
413  s->avctx->pix_fmt = new_pix_fmt;
414  avcodec_set_dimensions(s->avctx, s->w, s->h);
415  av_fast_malloc(&s->vert_pred, &s->vert_pred_size, s->avctx->width * sizeof(unsigned int));
416  }
417 
418  /* There is 1 change bit per 4 pixels, so each change byte represents
419  * 32 pixels; divide width by 4 to obtain the number of change bits and
420  * then round up to the nearest byte. */
421  s->mb_change_bits_row_size = ((s->avctx->width >> (2 - width_shift)) + 7) >> 3;
422 
423  if ((header.deltaset != s->last_deltaset) || (header.vectable != s->last_vectable))
424  {
425  if (compression_types[header.compression].algorithm == ALGO_RGB24H)
426  gen_vector_table24(s, sel_vector_table);
427  else
428  if (s->avctx->pix_fmt == PIX_FMT_RGB555)
429  gen_vector_table15(s, sel_vector_table);
430  else
431  gen_vector_table16(s, sel_vector_table);
432  }
433 
434  /* set up pointers to the other key data chunks */
435  s->mb_change_bits = s->buf + header.header_size;
436  if (s->flags & FLAG_KEYFRAME) {
437  /* no change bits specified for a keyframe; only index bytes */
439  } else {
440  /* one change bit per 4x4 block */
441  s->index_stream = s->mb_change_bits +
442  (s->mb_change_bits_row_size * (s->avctx->height >> 2));
443  }
444  s->index_stream_size = s->size - (s->index_stream - s->buf);
445 
446  s->last_deltaset = header.deltaset;
447  s->last_vectable = header.vectable;
448  s->compression = header.compression;
449  s->block_width = compression_types[header.compression].block_width;
450  s->block_height = compression_types[header.compression].block_height;
451  s->block_type = compression_types[header.compression].block_type;
452 
453  if (s->avctx->debug & FF_DEBUG_PICT_INFO)
454  av_log(s->avctx, AV_LOG_INFO, "tables: %d / %d c:%d %dx%d t:%d %s%s%s%s\n",
456  s->block_height, s->block_type,
457  s->flags & FLAG_KEYFRAME ? " KEY" : "",
458  s->flags & FLAG_INTERFRAME ? " INTER" : "",
459  s->flags & FLAG_SPRITE ? " SPRITE" : "",
460  s->flags & FLAG_INTERPOLATED ? " INTERPOL" : "");
461 
462  return header.header_size;
463 }
464 
466 {
467  TrueMotion1Context *s = avctx->priv_data;
468 
469  s->avctx = avctx;
470 
471  // FIXME: it may change ?
472 // if (avctx->bits_per_sample == 24)
473 // avctx->pix_fmt = PIX_FMT_RGB24;
474 // else
475 // avctx->pix_fmt = PIX_FMT_RGB555;
476 
477  s->frame.data[0] = NULL;
478 
479  /* there is a vertical predictor for each pixel in a line; each vertical
480  * predictor is 0 to start with */
481  av_fast_malloc(&s->vert_pred, &s->vert_pred_size, s->avctx->width * sizeof(unsigned int));
482 
483  return 0;
484 }
485 
486 /*
487 Block decoding order:
488 
489 dxi: Y-Y
490 dxic: Y-C-Y
491 dxic2: Y-C-Y-C
492 
493 hres,vres,i,i%vres (0 < i < 4)
494 2x2 0: 0 dxic2
495 2x2 1: 1 dxi
496 2x2 2: 0 dxic2
497 2x2 3: 1 dxi
498 2x4 0: 0 dxic2
499 2x4 1: 1 dxi
500 2x4 2: 2 dxi
501 2x4 3: 3 dxi
502 4x2 0: 0 dxic
503 4x2 1: 1 dxi
504 4x2 2: 0 dxic
505 4x2 3: 1 dxi
506 4x4 0: 0 dxic
507 4x4 1: 1 dxi
508 4x4 2: 2 dxi
509 4x4 3: 3 dxi
510 */
511 
512 #define GET_NEXT_INDEX() \
513 {\
514  if (index_stream_index >= s->index_stream_size) { \
515  av_log(s->avctx, AV_LOG_INFO, " help! truemotion1 decoder went out of bounds\n"); \
516  return; \
517  } \
518  index = s->index_stream[index_stream_index++] * 4; \
519 }
520 
521 #define APPLY_C_PREDICTOR() \
522  predictor_pair = s->c_predictor_table[index]; \
523  horiz_pred += (predictor_pair >> 1); \
524  if (predictor_pair & 1) { \
525  GET_NEXT_INDEX() \
526  if (!index) { \
527  GET_NEXT_INDEX() \
528  predictor_pair = s->c_predictor_table[index]; \
529  horiz_pred += ((predictor_pair >> 1) * 5); \
530  if (predictor_pair & 1) \
531  GET_NEXT_INDEX() \
532  else \
533  index++; \
534  } \
535  } else \
536  index++;
537 
538 #define APPLY_C_PREDICTOR_24() \
539  predictor_pair = s->c_predictor_table[index]; \
540  horiz_pred += (predictor_pair >> 1); \
541  if (predictor_pair & 1) { \
542  GET_NEXT_INDEX() \
543  if (!index) { \
544  GET_NEXT_INDEX() \
545  predictor_pair = s->fat_c_predictor_table[index]; \
546  horiz_pred += (predictor_pair >> 1); \
547  if (predictor_pair & 1) \
548  GET_NEXT_INDEX() \
549  else \
550  index++; \
551  } \
552  } else \
553  index++;
554 
555 
556 #define APPLY_Y_PREDICTOR() \
557  predictor_pair = s->y_predictor_table[index]; \
558  horiz_pred += (predictor_pair >> 1); \
559  if (predictor_pair & 1) { \
560  GET_NEXT_INDEX() \
561  if (!index) { \
562  GET_NEXT_INDEX() \
563  predictor_pair = s->y_predictor_table[index]; \
564  horiz_pred += ((predictor_pair >> 1) * 5); \
565  if (predictor_pair & 1) \
566  GET_NEXT_INDEX() \
567  else \
568  index++; \
569  } \
570  } else \
571  index++;
572 
573 #define APPLY_Y_PREDICTOR_24() \
574  predictor_pair = s->y_predictor_table[index]; \
575  horiz_pred += (predictor_pair >> 1); \
576  if (predictor_pair & 1) { \
577  GET_NEXT_INDEX() \
578  if (!index) { \
579  GET_NEXT_INDEX() \
580  predictor_pair = s->fat_y_predictor_table[index]; \
581  horiz_pred += (predictor_pair >> 1); \
582  if (predictor_pair & 1) \
583  GET_NEXT_INDEX() \
584  else \
585  index++; \
586  } \
587  } else \
588  index++;
589 
590 #define OUTPUT_PIXEL_PAIR() \
591  *current_pixel_pair = *vert_pred + horiz_pred; \
592  *vert_pred++ = *current_pixel_pair++;
593 
595 {
596  int y;
597  int pixels_left; /* remaining pixels on this line */
598  unsigned int predictor_pair;
599  unsigned int horiz_pred;
600  unsigned int *vert_pred;
601  unsigned int *current_pixel_pair;
602  unsigned char *current_line = s->frame.data[0];
603  int keyframe = s->flags & FLAG_KEYFRAME;
604 
605  /* these variables are for managing the stream of macroblock change bits */
606  const unsigned char *mb_change_bits = s->mb_change_bits;
607  unsigned char mb_change_byte;
608  unsigned char mb_change_byte_mask;
609  int mb_change_index;
610 
611  /* these variables are for managing the main index stream */
612  int index_stream_index = 0; /* yes, the index into the index stream */
613  int index;
614 
615  /* clean out the line buffer */
616  memset(s->vert_pred, 0, s->avctx->width * sizeof(unsigned int));
617 
618  GET_NEXT_INDEX();
619 
620  for (y = 0; y < s->avctx->height; y++) {
621 
622  /* re-init variables for the next line iteration */
623  horiz_pred = 0;
624  current_pixel_pair = (unsigned int *)current_line;
625  vert_pred = s->vert_pred;
626  mb_change_index = 0;
627  mb_change_byte = mb_change_bits[mb_change_index++];
628  mb_change_byte_mask = 0x01;
629  pixels_left = s->avctx->width;
630 
631  while (pixels_left > 0) {
632 
633  if (keyframe || ((mb_change_byte & mb_change_byte_mask) == 0)) {
634 
635  switch (y & 3) {
636  case 0:
637  /* if macroblock width is 2, apply C-Y-C-Y; else
638  * apply C-Y-Y */
639  if (s->block_width == 2) {
646  } else {
652  }
653  break;
654 
655  case 1:
656  case 3:
657  /* always apply 2 Y predictors on these iterations */
662  break;
663 
664  case 2:
665  /* this iteration might be C-Y-C-Y, Y-Y, or C-Y-Y
666  * depending on the macroblock type */
667  if (s->block_type == BLOCK_2x2) {
674  } else if (s->block_type == BLOCK_4x2) {
680  } else {
685  }
686  break;
687  }
688 
689  } else {
690 
691  /* skip (copy) four pixels, but reassign the horizontal
692  * predictor */
693  *vert_pred++ = *current_pixel_pair++;
694  horiz_pred = *current_pixel_pair - *vert_pred;
695  *vert_pred++ = *current_pixel_pair++;
696 
697  }
698 
699  if (!keyframe) {
700  mb_change_byte_mask <<= 1;
701 
702  /* next byte */
703  if (!mb_change_byte_mask) {
704  mb_change_byte = mb_change_bits[mb_change_index++];
705  mb_change_byte_mask = 0x01;
706  }
707  }
708 
709  pixels_left -= 4;
710  }
711 
712  /* next change row */
713  if (((y + 1) & 3) == 0)
714  mb_change_bits += s->mb_change_bits_row_size;
715 
716  current_line += s->frame.linesize[0];
717  }
718 }
719 
721 {
722  int y;
723  int pixels_left; /* remaining pixels on this line */
724  unsigned int predictor_pair;
725  unsigned int horiz_pred;
726  unsigned int *vert_pred;
727  unsigned int *current_pixel_pair;
728  unsigned char *current_line = s->frame.data[0];
729  int keyframe = s->flags & FLAG_KEYFRAME;
730 
731  /* these variables are for managing the stream of macroblock change bits */
732  const unsigned char *mb_change_bits = s->mb_change_bits;
733  unsigned char mb_change_byte;
734  unsigned char mb_change_byte_mask;
735  int mb_change_index;
736 
737  /* these variables are for managing the main index stream */
738  int index_stream_index = 0; /* yes, the index into the index stream */
739  int index;
740 
741  /* clean out the line buffer */
742  memset(s->vert_pred, 0, s->avctx->width * sizeof(unsigned int));
743 
744  GET_NEXT_INDEX();
745 
746  for (y = 0; y < s->avctx->height; y++) {
747 
748  /* re-init variables for the next line iteration */
749  horiz_pred = 0;
750  current_pixel_pair = (unsigned int *)current_line;
751  vert_pred = s->vert_pred;
752  mb_change_index = 0;
753  mb_change_byte = mb_change_bits[mb_change_index++];
754  mb_change_byte_mask = 0x01;
755  pixels_left = s->avctx->width;
756 
757  while (pixels_left > 0) {
758 
759  if (keyframe || ((mb_change_byte & mb_change_byte_mask) == 0)) {
760 
761  switch (y & 3) {
762  case 0:
763  /* if macroblock width is 2, apply C-Y-C-Y; else
764  * apply C-Y-Y */
765  if (s->block_width == 2) {
772  } else {
778  }
779  break;
780 
781  case 1:
782  case 3:
783  /* always apply 2 Y predictors on these iterations */
788  break;
789 
790  case 2:
791  /* this iteration might be C-Y-C-Y, Y-Y, or C-Y-Y
792  * depending on the macroblock type */
793  if (s->block_type == BLOCK_2x2) {
800  } else if (s->block_type == BLOCK_4x2) {
806  } else {
811  }
812  break;
813  }
814 
815  } else {
816 
817  /* skip (copy) four pixels, but reassign the horizontal
818  * predictor */
819  *vert_pred++ = *current_pixel_pair++;
820  horiz_pred = *current_pixel_pair - *vert_pred;
821  *vert_pred++ = *current_pixel_pair++;
822 
823  }
824 
825  if (!keyframe) {
826  mb_change_byte_mask <<= 1;
827 
828  /* next byte */
829  if (!mb_change_byte_mask) {
830  mb_change_byte = mb_change_bits[mb_change_index++];
831  mb_change_byte_mask = 0x01;
832  }
833  }
834 
835  pixels_left -= 2;
836  }
837 
838  /* next change row */
839  if (((y + 1) & 3) == 0)
840  mb_change_bits += s->mb_change_bits_row_size;
841 
842  current_line += s->frame.linesize[0];
843  }
844 }
845 
846 
848  void *data, int *data_size,
849  AVPacket *avpkt)
850 {
851  const uint8_t *buf = avpkt->data;
852  int buf_size = avpkt->size;
853  TrueMotion1Context *s = avctx->priv_data;
854 
855  s->buf = buf;
856  s->size = buf_size;
857 
858  if (truemotion1_decode_header(s) == -1)
859  return -1;
860 
861  s->frame.reference = 1;
864  if (avctx->reget_buffer(avctx, &s->frame) < 0) {
865  av_log(s->avctx, AV_LOG_ERROR, "get_buffer() failed\n");
866  return -1;
867  }
868 
869  if (compression_types[s->compression].algorithm == ALGO_RGB24H) {
871  } else if (compression_types[s->compression].algorithm != ALGO_NOP) {
873  }
874 
875  *data_size = sizeof(AVFrame);
876  *(AVFrame*)data = s->frame;
877 
878  /* report that the buffer was completely consumed */
879  return buf_size;
880 }
881 
883 {
884  TrueMotion1Context *s = avctx->priv_data;
885 
886  if (s->frame.data[0])
887  avctx->release_buffer(avctx, &s->frame);
888 
889  av_free(s->vert_pred);
890 
891  return 0;
892 }
893 
895  .name = "truemotion1",
896  .type = AVMEDIA_TYPE_VIDEO,
897  .id = CODEC_ID_TRUEMOTION1,
898  .priv_data_size = sizeof(TrueMotion1Context),
902  .capabilities = CODEC_CAP_DR1,
903  .long_name = NULL_IF_CONFIG_SMALL("Duck TrueMotion 1.0"),
904 };