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  if (header.header_size + 1 > s->size) {
324  av_log(s->avctx, AV_LOG_ERROR, "Input packet too small.\n");
325  return AVERROR_INVALIDDATA;
326  }
327 
328  /* unscramble the header bytes with a XOR operation */
329  memset(header_buffer, 0, 128);
330  for (i = 1; i < header.header_size; i++)
331  header_buffer[i - 1] = s->buf[i] ^ s->buf[i + 1];
332 
333  header.compression = header_buffer[0];
334  header.deltaset = header_buffer[1];
335  header.vectable = header_buffer[2];
336  header.ysize = AV_RL16(&header_buffer[3]);
337  header.xsize = AV_RL16(&header_buffer[5]);
338  header.checksum = AV_RL16(&header_buffer[7]);
339  header.version = header_buffer[9];
340  header.header_type = header_buffer[10];
341  header.flags = header_buffer[11];
342  header.control = header_buffer[12];
343 
344  /* Version 2 */
345  if (header.version >= 2)
346  {
347  if (header.header_type > 3)
348  {
349  av_log(s->avctx, AV_LOG_ERROR, "invalid header type (%d)\n", header.header_type);
350  return -1;
351  } else if ((header.header_type == 2) || (header.header_type == 3)) {
352  s->flags = header.flags;
353  if (!(s->flags & FLAG_INTERFRAME))
354  s->flags |= FLAG_KEYFRAME;
355  } else
356  s->flags = FLAG_KEYFRAME;
357  } else /* Version 1 */
358  s->flags = FLAG_KEYFRAME;
359 
360  if (s->flags & FLAG_SPRITE) {
361  av_log_ask_for_sample(s->avctx, "SPRITE frame found.\n");
362  /* FIXME header.width, height, xoffset and yoffset aren't initialized */
363 #if 0
364  s->w = header.width;
365  s->h = header.height;
366  s->x = header.xoffset;
367  s->y = header.yoffset;
368 #else
369  return -1;
370 #endif
371  } else {
372  s->w = header.xsize;
373  s->h = header.ysize;
374  if (header.header_type < 2) {
375  if ((s->w < 213) && (s->h >= 176))
376  {
377  s->flags |= FLAG_INTERPOLATED;
378  av_log_ask_for_sample(s->avctx, "INTERPOLATION selected.\n");
379  }
380  }
381  }
382 
383  if (header.compression >= 17) {
384  av_log(s->avctx, AV_LOG_ERROR, "invalid compression type (%d)\n", header.compression);
385  return -1;
386  }
387 
388  if ((header.deltaset != s->last_deltaset) ||
389  (header.vectable != s->last_vectable))
390  select_delta_tables(s, header.deltaset);
391 
392  if ((header.compression & 1) && header.header_type)
393  sel_vector_table = pc_tbl2;
394  else {
395  if (header.vectable > 0 && header.vectable < 4)
396  sel_vector_table = tables[header.vectable - 1];
397  else {
398  av_log(s->avctx, AV_LOG_ERROR, "invalid vector table id (%d)\n", header.vectable);
399  return -1;
400  }
401  }
402 
403  if (compression_types[header.compression].algorithm == ALGO_RGB24H) {
404  new_pix_fmt = PIX_FMT_RGB32;
405  width_shift = 1;
406  } else
407  new_pix_fmt = PIX_FMT_RGB555; // RGB565 is supported as well
408 
409  s->w >>= width_shift;
410  if (av_image_check_size(s->w, s->h, 0, s->avctx) < 0)
411  return -1;
412 
413  if (s->w != s->avctx->width || s->h != s->avctx->height ||
414  new_pix_fmt != s->avctx->pix_fmt) {
415  if (s->frame.data[0])
416  s->avctx->release_buffer(s->avctx, &s->frame);
417  s->avctx->sample_aspect_ratio = (AVRational){ 1 << width_shift, 1 };
418  s->avctx->pix_fmt = new_pix_fmt;
419  avcodec_set_dimensions(s->avctx, s->w, s->h);
420  av_fast_malloc(&s->vert_pred, &s->vert_pred_size, s->avctx->width * sizeof(unsigned int));
421  }
422 
423  /* There is 1 change bit per 4 pixels, so each change byte represents
424  * 32 pixels; divide width by 4 to obtain the number of change bits and
425  * then round up to the nearest byte. */
426  s->mb_change_bits_row_size = ((s->avctx->width >> (2 - width_shift)) + 7) >> 3;
427 
428  if ((header.deltaset != s->last_deltaset) || (header.vectable != s->last_vectable))
429  {
430  if (compression_types[header.compression].algorithm == ALGO_RGB24H)
431  gen_vector_table24(s, sel_vector_table);
432  else
433  if (s->avctx->pix_fmt == PIX_FMT_RGB555)
434  gen_vector_table15(s, sel_vector_table);
435  else
436  gen_vector_table16(s, sel_vector_table);
437  }
438 
439  /* set up pointers to the other key data chunks */
440  s->mb_change_bits = s->buf + header.header_size;
441  if (s->flags & FLAG_KEYFRAME) {
442  /* no change bits specified for a keyframe; only index bytes */
444  } else {
445  /* one change bit per 4x4 block */
446  s->index_stream = s->mb_change_bits +
447  (s->mb_change_bits_row_size * (s->avctx->height >> 2));
448  }
449  s->index_stream_size = s->size - (s->index_stream - s->buf);
450 
451  s->last_deltaset = header.deltaset;
452  s->last_vectable = header.vectable;
453  s->compression = header.compression;
454  s->block_width = compression_types[header.compression].block_width;
455  s->block_height = compression_types[header.compression].block_height;
456  s->block_type = compression_types[header.compression].block_type;
457 
458  if (s->avctx->debug & FF_DEBUG_PICT_INFO)
459  av_log(s->avctx, AV_LOG_INFO, "tables: %d / %d c:%d %dx%d t:%d %s%s%s%s\n",
461  s->block_height, s->block_type,
462  s->flags & FLAG_KEYFRAME ? " KEY" : "",
463  s->flags & FLAG_INTERFRAME ? " INTER" : "",
464  s->flags & FLAG_SPRITE ? " SPRITE" : "",
465  s->flags & FLAG_INTERPOLATED ? " INTERPOL" : "");
466 
467  return header.header_size;
468 }
469 
471 {
472  TrueMotion1Context *s = avctx->priv_data;
473 
474  s->avctx = avctx;
475 
476  // FIXME: it may change ?
477 // if (avctx->bits_per_sample == 24)
478 // avctx->pix_fmt = PIX_FMT_RGB24;
479 // else
480 // avctx->pix_fmt = PIX_FMT_RGB555;
481 
482  s->frame.data[0] = NULL;
483 
484  /* there is a vertical predictor for each pixel in a line; each vertical
485  * predictor is 0 to start with */
486  av_fast_malloc(&s->vert_pred, &s->vert_pred_size, s->avctx->width * sizeof(unsigned int));
487 
488  return 0;
489 }
490 
491 /*
492 Block decoding order:
493 
494 dxi: Y-Y
495 dxic: Y-C-Y
496 dxic2: Y-C-Y-C
497 
498 hres,vres,i,i%vres (0 < i < 4)
499 2x2 0: 0 dxic2
500 2x2 1: 1 dxi
501 2x2 2: 0 dxic2
502 2x2 3: 1 dxi
503 2x4 0: 0 dxic2
504 2x4 1: 1 dxi
505 2x4 2: 2 dxi
506 2x4 3: 3 dxi
507 4x2 0: 0 dxic
508 4x2 1: 1 dxi
509 4x2 2: 0 dxic
510 4x2 3: 1 dxi
511 4x4 0: 0 dxic
512 4x4 1: 1 dxi
513 4x4 2: 2 dxi
514 4x4 3: 3 dxi
515 */
516 
517 #define GET_NEXT_INDEX() \
518 {\
519  if (index_stream_index >= s->index_stream_size) { \
520  av_log(s->avctx, AV_LOG_INFO, " help! truemotion1 decoder went out of bounds\n"); \
521  return; \
522  } \
523  index = s->index_stream[index_stream_index++] * 4; \
524 }
525 
526 #define APPLY_C_PREDICTOR() \
527  predictor_pair = s->c_predictor_table[index]; \
528  horiz_pred += (predictor_pair >> 1); \
529  if (predictor_pair & 1) { \
530  GET_NEXT_INDEX() \
531  if (!index) { \
532  GET_NEXT_INDEX() \
533  predictor_pair = s->c_predictor_table[index]; \
534  horiz_pred += ((predictor_pair >> 1) * 5); \
535  if (predictor_pair & 1) \
536  GET_NEXT_INDEX() \
537  else \
538  index++; \
539  } \
540  } else \
541  index++;
542 
543 #define APPLY_C_PREDICTOR_24() \
544  predictor_pair = s->c_predictor_table[index]; \
545  horiz_pred += (predictor_pair >> 1); \
546  if (predictor_pair & 1) { \
547  GET_NEXT_INDEX() \
548  if (!index) { \
549  GET_NEXT_INDEX() \
550  predictor_pair = s->fat_c_predictor_table[index]; \
551  horiz_pred += (predictor_pair >> 1); \
552  if (predictor_pair & 1) \
553  GET_NEXT_INDEX() \
554  else \
555  index++; \
556  } \
557  } else \
558  index++;
559 
560 
561 #define APPLY_Y_PREDICTOR() \
562  predictor_pair = s->y_predictor_table[index]; \
563  horiz_pred += (predictor_pair >> 1); \
564  if (predictor_pair & 1) { \
565  GET_NEXT_INDEX() \
566  if (!index) { \
567  GET_NEXT_INDEX() \
568  predictor_pair = s->y_predictor_table[index]; \
569  horiz_pred += ((predictor_pair >> 1) * 5); \
570  if (predictor_pair & 1) \
571  GET_NEXT_INDEX() \
572  else \
573  index++; \
574  } \
575  } else \
576  index++;
577 
578 #define APPLY_Y_PREDICTOR_24() \
579  predictor_pair = s->y_predictor_table[index]; \
580  horiz_pred += (predictor_pair >> 1); \
581  if (predictor_pair & 1) { \
582  GET_NEXT_INDEX() \
583  if (!index) { \
584  GET_NEXT_INDEX() \
585  predictor_pair = s->fat_y_predictor_table[index]; \
586  horiz_pred += (predictor_pair >> 1); \
587  if (predictor_pair & 1) \
588  GET_NEXT_INDEX() \
589  else \
590  index++; \
591  } \
592  } else \
593  index++;
594 
595 #define OUTPUT_PIXEL_PAIR() \
596  *current_pixel_pair = *vert_pred + horiz_pred; \
597  *vert_pred++ = *current_pixel_pair++;
598 
600 {
601  int y;
602  int pixels_left; /* remaining pixels on this line */
603  unsigned int predictor_pair;
604  unsigned int horiz_pred;
605  unsigned int *vert_pred;
606  unsigned int *current_pixel_pair;
607  unsigned char *current_line = s->frame.data[0];
608  int keyframe = s->flags & FLAG_KEYFRAME;
609 
610  /* these variables are for managing the stream of macroblock change bits */
611  const unsigned char *mb_change_bits = s->mb_change_bits;
612  unsigned char mb_change_byte;
613  unsigned char mb_change_byte_mask;
614  int mb_change_index;
615 
616  /* these variables are for managing the main index stream */
617  int index_stream_index = 0; /* yes, the index into the index stream */
618  int index;
619 
620  /* clean out the line buffer */
621  memset(s->vert_pred, 0, s->avctx->width * sizeof(unsigned int));
622 
623  GET_NEXT_INDEX();
624 
625  for (y = 0; y < s->avctx->height; y++) {
626 
627  /* re-init variables for the next line iteration */
628  horiz_pred = 0;
629  current_pixel_pair = (unsigned int *)current_line;
630  vert_pred = s->vert_pred;
631  mb_change_index = 0;
632  mb_change_byte = mb_change_bits[mb_change_index++];
633  mb_change_byte_mask = 0x01;
634  pixels_left = s->avctx->width;
635 
636  while (pixels_left > 0) {
637 
638  if (keyframe || ((mb_change_byte & mb_change_byte_mask) == 0)) {
639 
640  switch (y & 3) {
641  case 0:
642  /* if macroblock width is 2, apply C-Y-C-Y; else
643  * apply C-Y-Y */
644  if (s->block_width == 2) {
651  } else {
657  }
658  break;
659 
660  case 1:
661  case 3:
662  /* always apply 2 Y predictors on these iterations */
667  break;
668 
669  case 2:
670  /* this iteration might be C-Y-C-Y, Y-Y, or C-Y-Y
671  * depending on the macroblock type */
672  if (s->block_type == BLOCK_2x2) {
679  } else if (s->block_type == BLOCK_4x2) {
685  } else {
690  }
691  break;
692  }
693 
694  } else {
695 
696  /* skip (copy) four pixels, but reassign the horizontal
697  * predictor */
698  *vert_pred++ = *current_pixel_pair++;
699  horiz_pred = *current_pixel_pair - *vert_pred;
700  *vert_pred++ = *current_pixel_pair++;
701 
702  }
703 
704  if (!keyframe) {
705  mb_change_byte_mask <<= 1;
706 
707  /* next byte */
708  if (!mb_change_byte_mask) {
709  mb_change_byte = mb_change_bits[mb_change_index++];
710  mb_change_byte_mask = 0x01;
711  }
712  }
713 
714  pixels_left -= 4;
715  }
716 
717  /* next change row */
718  if (((y + 1) & 3) == 0)
719  mb_change_bits += s->mb_change_bits_row_size;
720 
721  current_line += s->frame.linesize[0];
722  }
723 }
724 
726 {
727  int y;
728  int pixels_left; /* remaining pixels on this line */
729  unsigned int predictor_pair;
730  unsigned int horiz_pred;
731  unsigned int *vert_pred;
732  unsigned int *current_pixel_pair;
733  unsigned char *current_line = s->frame.data[0];
734  int keyframe = s->flags & FLAG_KEYFRAME;
735 
736  /* these variables are for managing the stream of macroblock change bits */
737  const unsigned char *mb_change_bits = s->mb_change_bits;
738  unsigned char mb_change_byte;
739  unsigned char mb_change_byte_mask;
740  int mb_change_index;
741 
742  /* these variables are for managing the main index stream */
743  int index_stream_index = 0; /* yes, the index into the index stream */
744  int index;
745 
746  /* clean out the line buffer */
747  memset(s->vert_pred, 0, s->avctx->width * sizeof(unsigned int));
748 
749  GET_NEXT_INDEX();
750 
751  for (y = 0; y < s->avctx->height; y++) {
752 
753  /* re-init variables for the next line iteration */
754  horiz_pred = 0;
755  current_pixel_pair = (unsigned int *)current_line;
756  vert_pred = s->vert_pred;
757  mb_change_index = 0;
758  mb_change_byte = mb_change_bits[mb_change_index++];
759  mb_change_byte_mask = 0x01;
760  pixels_left = s->avctx->width;
761 
762  while (pixels_left > 0) {
763 
764  if (keyframe || ((mb_change_byte & mb_change_byte_mask) == 0)) {
765 
766  switch (y & 3) {
767  case 0:
768  /* if macroblock width is 2, apply C-Y-C-Y; else
769  * apply C-Y-Y */
770  if (s->block_width == 2) {
777  } else {
783  }
784  break;
785 
786  case 1:
787  case 3:
788  /* always apply 2 Y predictors on these iterations */
793  break;
794 
795  case 2:
796  /* this iteration might be C-Y-C-Y, Y-Y, or C-Y-Y
797  * depending on the macroblock type */
798  if (s->block_type == BLOCK_2x2) {
805  } else if (s->block_type == BLOCK_4x2) {
811  } else {
816  }
817  break;
818  }
819 
820  } else {
821 
822  /* skip (copy) four pixels, but reassign the horizontal
823  * predictor */
824  *vert_pred++ = *current_pixel_pair++;
825  horiz_pred = *current_pixel_pair - *vert_pred;
826  *vert_pred++ = *current_pixel_pair++;
827 
828  }
829 
830  if (!keyframe) {
831  mb_change_byte_mask <<= 1;
832 
833  /* next byte */
834  if (!mb_change_byte_mask) {
835  mb_change_byte = mb_change_bits[mb_change_index++];
836  mb_change_byte_mask = 0x01;
837  }
838  }
839 
840  pixels_left -= 2;
841  }
842 
843  /* next change row */
844  if (((y + 1) & 3) == 0)
845  mb_change_bits += s->mb_change_bits_row_size;
846 
847  current_line += s->frame.linesize[0];
848  }
849 }
850 
851 
853  void *data, int *data_size,
854  AVPacket *avpkt)
855 {
856  const uint8_t *buf = avpkt->data;
857  int buf_size = avpkt->size;
858  TrueMotion1Context *s = avctx->priv_data;
859 
860  s->buf = buf;
861  s->size = buf_size;
862 
863  if (truemotion1_decode_header(s) == -1)
864  return -1;
865 
866  s->frame.reference = 1;
869  if (avctx->reget_buffer(avctx, &s->frame) < 0) {
870  av_log(s->avctx, AV_LOG_ERROR, "get_buffer() failed\n");
871  return -1;
872  }
873 
874  if (compression_types[s->compression].algorithm == ALGO_RGB24H) {
876  } else if (compression_types[s->compression].algorithm != ALGO_NOP) {
878  }
879 
880  *data_size = sizeof(AVFrame);
881  *(AVFrame*)data = s->frame;
882 
883  /* report that the buffer was completely consumed */
884  return buf_size;
885 }
886 
888 {
889  TrueMotion1Context *s = avctx->priv_data;
890 
891  if (s->frame.data[0])
892  avctx->release_buffer(avctx, &s->frame);
893 
894  av_free(s->vert_pred);
895 
896  return 0;
897 }
898 
900  .name = "truemotion1",
901  .type = AVMEDIA_TYPE_VIDEO,
902  .id = CODEC_ID_TRUEMOTION1,
903  .priv_data_size = sizeof(TrueMotion1Context),
907  .capabilities = CODEC_CAP_DR1,
908  .long_name = NULL_IF_CONFIG_SMALL("Duck TrueMotion 1.0"),
909 };