libavcodec/truemotion1.c

   1 /*
   2  * Duck TrueMotion 1.0 Decoder
   3  * Copyright (C) 2003 Alex Beregszaszi & Mike Melanson
   4  *
   5  * This file is part of FFmpeg.
   6  *
   7  * FFmpeg 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  * FFmpeg 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 FFmpeg; if not, write to the Free Software
  19  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
  20  */
  21
  22 /**
  23  * @file libavcodec/truemotion1.c
  24  * Duck TrueMotion v1 Video Decoder by
  25  * Alex Beregszaszi and
  26  * Mike Melanson (melanson@pcisys.net)
  27  *
  28  * The TrueMotion v1 decoder presently only decodes 16-bit TM1 data and
  29  * outputs RGB555 (or RGB565) data. 24-bit TM1 data is not supported yet.
  30  */
  31
  32 #include <stdio.h>
  33 #include <stdlib.h>
  34 #include <string.h>
  35
  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
  45     const uint8_t *buf;
  46     int size;
  47
  48     const uint8_t *mb_change_bits;
  49     int mb_change_bits_row_size;
  50     const uint8_t *index_stream;
  51     int index_stream_size;
  52
  53     int flags;
  54     int x, y, w, h;
  55
  56     uint32_t y_predictor_table[1024];
  57     uint32_t c_predictor_table[1024];
  58     uint32_t fat_y_predictor_table[1024];
  59     uint32_t fat_c_predictor_table[1024];
  60
  61     int compression;
  62     int block_type;
  63     int block_width;
  64     int block_height;
  65
  66     int16_t ydt[8];
  67     int16_t cdt[8];
  68     int16_t fat_ydt[8];
  69     int16_t fat_cdt[8];
  70
  71     int last_deltaset, last_vectable;
  72
  73     unsigned int *vert_pred;
  74
  75 } TrueMotion1Context;
  76
  77 #define FLAG_SPRITE         32
  78 #define FLAG_KEYFRAME       16
  79 #define FLAG_INTERFRAME      8
  80 #define FLAG_INTERPOLATED    4
  81
  82 struct frame_header {
  83     uint8_t header_size;
  84     uint8_t compression;
  85     uint8_t deltaset;
  86     uint8_t vectable;
  87     uint16_t ysize;
  88     uint16_t xsize;
  89     uint16_t checksum;
  90     uint8_t version;
  91     uint8_t header_type;
  92     uint8_t flags;
  93     uint8_t control;
  94     uint16_t xoffset;
  95     uint16_t yoffset;
  96     uint16_t width;
  97     uint16_t height;
  98 };
  99
 100 #define ALGO_NOP        0
 101 #define ALGO_RGB16V     1
 102 #define ALGO_RGB16H     2
 103 #define ALGO_RGB24H     3
 104
 105 /* these are the various block sizes that can occupy a 4x4 block */
 106 #define BLOCK_2x2  0
 107 #define BLOCK_2x4  1
 108 #define BLOCK_4x2  2
 109 #define BLOCK_4x4  3
 110
 111 typedef struct comp_types {
 112     int algorithm;
 113     int block_width; // vres
 114     int block_height; // hres
 115     int block_type;
 116 } comp_types;
 117
 118 /* { valid for metatype }, algorithm, num of deltas, vert res, horiz res */
 119 static const comp_types compression_types[17] = {
 120     { ALGO_NOP,    0, 0, 0 },
 121
 122     { ALGO_RGB16V, 4, 4, BLOCK_4x4 },
 123     { ALGO_RGB16H, 4, 4, BLOCK_4x4 },
 124     { ALGO_RGB16V, 4, 2, BLOCK_4x2 },
 125     { ALGO_RGB16H, 4, 2, BLOCK_4x2 },
 126
 127     { ALGO_RGB16V, 2, 4, BLOCK_2x4 },
 128     { ALGO_RGB16H, 2, 4, BLOCK_2x4 },
 129     { ALGO_RGB16V, 2, 2, BLOCK_2x2 },
 130     { ALGO_RGB16H, 2, 2, BLOCK_2x2 },
 131
 132     { ALGO_NOP,    4, 4, BLOCK_4x4 },
 133     { ALGO_RGB24H, 4, 4, BLOCK_4x4 },
 134     { ALGO_NOP,    4, 2, BLOCK_4x2 },
 135     { ALGO_RGB24H, 4, 2, BLOCK_4x2 },
 136
 137     { ALGO_NOP,    2, 4, BLOCK_2x4 },
 138     { ALGO_RGB24H, 2, 4, BLOCK_2x4 },
 139     { ALGO_NOP,    2, 2, BLOCK_2x2 },
 140     { ALGO_RGB24H, 2, 2, BLOCK_2x2 }
 141 };
 142
 143 static void select_delta_tables(TrueMotion1Context *s, int delta_table_index)
 144 {
 145     int i;
 146
 147     if (delta_table_index > 3)
 148         return;
 149
 150     memcpy(s->ydt, ydts[delta_table_index], 8 * sizeof(int16_t));
 151     memcpy(s->cdt, cdts[delta_table_index], 8 * sizeof(int16_t));
 152     memcpy(s->fat_ydt, fat_ydts[delta_table_index], 8 * sizeof(int16_t));
 153     memcpy(s->fat_cdt, fat_cdts[delta_table_index], 8 * sizeof(int16_t));
 154
 155     /* Y skinny deltas need to be halved for some reason; maybe the
 156      * skinny Y deltas should be modified */
 157     for (i = 0; i < 8; i++)
 158     {
 159         /* drop the lsb before dividing by 2-- net effect: round down
 160          * when dividing a negative number (e.g., -3/2 = -2, not -1) */
 161         s->ydt[i] &= 0xFFFE;
 162         s->ydt[i] /= 2;
 163     }
 164 }
 165
 166 #if HAVE_BIGENDIAN
 167 static int make_ydt15_entry(int p2, int p1, int16_t *ydt)
 168 #else
 169 static int make_ydt15_entry(int p1, int p2, int16_t *ydt)
 170 #endif
 171 {
 172     int lo, hi;
 173
 174     lo = ydt[p1];
 175     lo += (lo << 5) + (lo << 10);
 176     hi = ydt[p2];
 177     hi += (hi << 5) + (hi << 10);
 178     return (lo + (hi << 16)) << 1;
 179 }
 180
 181 #if HAVE_BIGENDIAN
 182 static int make_cdt15_entry(int p2, int p1, int16_t *cdt)
 183 #else
 184 static int make_cdt15_entry(int p1, int p2, int16_t *cdt)
 185 #endif
 186 {
 187     int r, b, lo;
 188
 189     b = cdt[p2];
 190     r = cdt[p1] << 10;
 191     lo = b + r;
 192     return (lo + (lo << 16)) << 1;
 193 }
 194
 195 #if HAVE_BIGENDIAN
 196 static int make_ydt16_entry(int p2, int p1, int16_t *ydt)
 197 #else
 198 static int make_ydt16_entry(int p1, int p2, int16_t *ydt)
 199 #endif
 200 {
 201     int lo, hi;
 202
 203     lo = ydt[p1];
 204     lo += (lo << 6) + (lo << 11);
 205     hi = ydt[p2];
 206     hi += (hi << 6) + (hi << 11);
 207     return (lo + (hi << 16)) << 1;
 208 }
 209
 210 #if HAVE_BIGENDIAN
 211 static int make_cdt16_entry(int p2, int p1, int16_t *cdt)
 212 #else
 213 static int make_cdt16_entry(int p1, int p2, int16_t *cdt)
 214 #endif
 215 {
 216     int r, b, lo;
 217
 218     b = cdt[p2];
 219     r = cdt[p1] << 11;
 220     lo = b + r;
 221     return (lo + (lo << 16)) << 1;
 222 }
 223
 224 #if HAVE_BIGENDIAN
 225 static int make_ydt24_entry(int p2, int p1, int16_t *ydt)
 226 #else
 227 static int make_ydt24_entry(int p1, int p2, int16_t *ydt)
 228 #endif
 229 {
 230     int lo, hi;
 231
 232     lo = ydt[p1];
 233     hi = ydt[p2];
 234     return (lo + (hi << 8) + (hi << 16)) << 1;
 235 }
 236
 237 #if HAVE_BIGENDIAN
 238 static int make_cdt24_entry(int p2, int p1, int16_t *cdt)
 239 #else
 240 static int make_cdt24_entry(int p1, int p2, int16_t *cdt)
 241 #endif
 242 {
 243     int r, b;
 244
 245     b = cdt[p2];
 246     r = cdt[p1]<<16;
 247     return (b+r) << 1;
 248 }
 249
 250 static void gen_vector_table15(TrueMotion1Context *s, const uint8_t *sel_vector_table)
 251 {
 252     int len, i, j;
 253     unsigned char delta_pair;
 254
 255     for (i = 0; i < 1024; i += 4)
 256     {
 257         len = *sel_vector_table++ / 2;
 258         for (j = 0; j < len; j++)
 259         {
 260             delta_pair = *sel_vector_table++;
 261             s->y_predictor_table[i+j] = 0xfffffffe &
 262                 make_ydt15_entry(delta_pair >> 4, delta_pair & 0xf, s->ydt);
 263             s->c_predictor_table[i+j] = 0xfffffffe &
 264                 make_cdt15_entry(delta_pair >> 4, delta_pair & 0xf, s->cdt);
 265         }
 266         s->y_predictor_table[i+(j-1)] |= 1;
 267         s->c_predictor_table[i+(j-1)] |= 1;
 268     }
 269 }
 270
 271 static void gen_vector_table16(TrueMotion1Context *s, const uint8_t *sel_vector_table)
 272 {
 273     int len, i, j;
 274     unsigned char delta_pair;
 275
 276     for (i = 0; i < 1024; i += 4)
 277     {
 278         len = *sel_vector_table++ / 2;
 279         for (j = 0; j < len; j++)
 280         {
 281             delta_pair = *sel_vector_table++;
 282             s->y_predictor_table[i+j] = 0xfffffffe &
 283                 make_ydt16_entry(delta_pair >> 4, delta_pair & 0xf, s->ydt);
 284             s->c_predictor_table[i+j] = 0xfffffffe &
 285                 make_cdt16_entry(delta_pair >> 4, delta_pair & 0xf, s->cdt);
 286         }
 287         s->y_predictor_table[i+(j-1)] |= 1;
 288         s->c_predictor_table[i+(j-1)] |= 1;
 289     }
 290 }
 291
 292 static void gen_vector_table24(TrueMotion1Context *s, const uint8_t *sel_vector_table)
 293 {
 294     int len, i, j;
 295     unsigned char delta_pair;
 296
 297     for (i = 0; i < 1024; i += 4)
 298     {
 299         len = *sel_vector_table++ / 2;
 300         for (j = 0; j < len; j++)
 301         {
 302             delta_pair = *sel_vector_table++;
 303             s->y_predictor_table[i+j] = 0xfffffffe &
 304                 make_ydt24_entry(delta_pair >> 4, delta_pair & 0xf, s->ydt);
 305             s->c_predictor_table[i+j] = 0xfffffffe &
 306                 make_cdt24_entry(delta_pair >> 4, delta_pair & 0xf, s->cdt);
 307             s->fat_y_predictor_table[i+j] = 0xfffffffe &
 308                 make_ydt24_entry(delta_pair >> 4, delta_pair & 0xf, s->fat_ydt);
 309             s->fat_c_predictor_table[i+j] = 0xfffffffe &
 310                 make_cdt24_entry(delta_pair >> 4, delta_pair & 0xf, s->fat_cdt);
 311         }
 312         s->y_predictor_table[i+(j-1)] |= 1;
 313         s->c_predictor_table[i+(j-1)] |= 1;
 314         s->fat_y_predictor_table[i+(j-1)] |= 1;
 315         s->fat_c_predictor_table[i+(j-1)] |= 1;
 316     }
 317 }
 318
 319 /* Returns the number of bytes consumed from the bytestream. Returns -1 if
 320  * there was an error while decoding the header */
 321 static int truemotion1_decode_header(TrueMotion1Context *s)
 322 {
 323     int i;
 324     struct frame_header header;
 325     uint8_t header_buffer[128];  /* logical maximum size of the header */
 326     const uint8_t *sel_vector_table;
 327
 328     /* There is 1 change bit per 4 pixels, so each change byte represents
 329      * 32 pixels; divide width by 4 to obtain the number of change bits and
 330      * then round up to the nearest byte. */
 331     s->mb_change_bits_row_size = ((s->avctx->width >> 2) + 7) >> 3;
 332
 333     header.header_size = ((s->buf[0] >> 5) | (s->buf[0] << 3)) & 0x7f;
 334     if (s->buf[0] < 0x10)
 335     {
 336         av_log(s->avctx, AV_LOG_ERROR, "invalid header size (%d)\n", s->buf[0]);
 337         return -1;
 338     }
 339
 340     /* unscramble the header bytes with a XOR operation */
 341     memset(header_buffer, 0, 128);
 342     for (i = 1; i < header.header_size; i++)
 343         header_buffer[i - 1] = s->buf[i] ^ s->buf[i + 1];
 344
 345     header.compression = header_buffer[0];
 346     header.deltaset = header_buffer[1];
 347     header.vectable = header_buffer[2];
 348     header.ysize = AV_RL16(&header_buffer[3]);
 349     header.xsize = AV_RL16(&header_buffer[5]);
 350     header.checksum = AV_RL16(&header_buffer[7]);
 351     header.version = header_buffer[9];
 352     header.header_type = header_buffer[10];
 353     header.flags = header_buffer[11];
 354     header.control = header_buffer[12];
 355
 356     /* Version 2 */
 357     if (header.version >= 2)
 358     {
 359         if (header.header_type > 3)
 360         {
 361             av_log(s->avctx, AV_LOG_ERROR, "invalid header type (%d)\n", header.header_type);
 362             return -1;
 363         } else if ((header.header_type == 2) || (header.header_type == 3)) {
 364             s->flags = header.flags;
 365             if (!(s->flags & FLAG_INTERFRAME))
 366                 s->flags |= FLAG_KEYFRAME;
 367         } else
 368             s->flags = FLAG_KEYFRAME;
 369     } else /* Version 1 */
 370         s->flags = FLAG_KEYFRAME;
 371
 372     if (s->flags & FLAG_SPRITE) {
 373         av_log(s->avctx, AV_LOG_INFO, "SPRITE frame found, please report the sample to the developers\n");
 374         /* FIXME header.width, height, xoffset and yoffset aren't initialized */
 375 #if 0
 376         s->w = header.width;
 377         s->h = header.height;
 378         s->x = header.xoffset;
 379         s->y = header.yoffset;
 380 #else
 381         return -1;
 382 #endif
 383     } else {
 384         s->w = header.xsize;
 385         s->h = header.ysize;
 386         if (header.header_type < 2) {
 387             if ((s->w < 213) && (s->h >= 176))
 388             {
 389                 s->flags |= FLAG_INTERPOLATED;
 390                 av_log(s->avctx, AV_LOG_INFO, "INTERPOLATION selected, please report the sample to the developers\n");
 391             }
 392         }
 393     }
 394
 395     if (header.compression >= 17) {
 396         av_log(s->avctx, AV_LOG_ERROR, "invalid compression type (%d)\n", header.compression);
 397         return -1;
 398     }
 399
 400     if ((header.deltaset != s->last_deltaset) ||
 401         (header.vectable != s->last_vectable))
 402         select_delta_tables(s, header.deltaset);
 403
 404     if ((header.compression & 1) && header.header_type)
 405         sel_vector_table = pc_tbl2;
 406     else {
 407         if (header.vectable < 4)
 408             sel_vector_table = tables[header.vectable - 1];
 409         else {
 410             av_log(s->avctx, AV_LOG_ERROR, "invalid vector table id (%d)\n", header.vectable);
 411             return -1;
 412         }
 413     }
 414
 415     // FIXME: where to place this ?!?!
 416     if (compression_types[header.compression].algorithm == ALGO_RGB24H)
 417         s->avctx->pix_fmt = PIX_FMT_RGB32;
 418     else
 419         s->avctx->pix_fmt = PIX_FMT_RGB555; // RGB565 is supported as well
 420
 421     if ((header.deltaset != s->last_deltaset) || (header.vectable != s->last_vectable))
 422     {
 423         if (compression_types[header.compression].algorithm == ALGO_RGB24H)
 424             gen_vector_table24(s, sel_vector_table);
 425         else
 426         if (s->avctx->pix_fmt == PIX_FMT_RGB555)
 427             gen_vector_table15(s, sel_vector_table);
 428         else
 429             gen_vector_table16(s, sel_vector_table);
 430     }
 431
 432     /* set up pointers to the other key data chunks */
 433     s->mb_change_bits = s->buf + header.header_size;
 434     if (s->flags & FLAG_KEYFRAME) {
 435         /* no change bits specified for a keyframe; only index bytes */
 436         s->index_stream = s->mb_change_bits;
 437     } else {
 438         /* one change bit per 4x4 block */
 439         s->index_stream = s->mb_change_bits +
 440             (s->mb_change_bits_row_size * (s->avctx->height >> 2));
 441     }
 442     s->index_stream_size = s->size - (s->index_stream - s->buf);
 443
 444     s->last_deltaset = header.deltaset;
 445     s->last_vectable = header.vectable;
 446     s->compression = header.compression;
 447     s->block_width = compression_types[header.compression].block_width;
 448     s->block_height = compression_types[header.compression].block_height;
 449     s->block_type = compression_types[header.compression].block_type;
 450
 451     if (s->avctx->debug & FF_DEBUG_PICT_INFO)
 452         av_log(s->avctx, AV_LOG_INFO, "tables: %d / %d c:%d %dx%d t:%d %s%s%s%s\n",
 453             s->last_deltaset, s->last_vectable, s->compression, s->block_width,
 454             s->block_height, s->block_type,
 455             s->flags & FLAG_KEYFRAME ? " KEY" : "",
 456             s->flags & FLAG_INTERFRAME ? " INTER" : "",
 457             s->flags & FLAG_SPRITE ? " SPRITE" : "",
 458             s->flags & FLAG_INTERPOLATED ? " INTERPOL" : "");
 459
 460     return header.header_size;
 461 }
 462
 463 static av_cold int truemotion1_decode_init(AVCodecContext *avctx)
 464 {
 465     TrueMotion1Context *s = avctx->priv_data;
 466
 467     s->avctx = avctx;
 468
 469     // FIXME: it may change ?
 470 //    if (avctx->bits_per_sample == 24)
 471 //        avctx->pix_fmt = PIX_FMT_RGB24;
 472 //    else
 473 //        avctx->pix_fmt = PIX_FMT_RGB555;
 474
 475     s->frame.data[0] = NULL;
 476
 477     /* there is a vertical predictor for each pixel in a line; each vertical
 478      * predictor is 0 to start with */
 479     s->vert_pred =
 480         (unsigned int *)av_malloc(s->avctx->width * sizeof(unsigned int));
 481
 482     return 0;
 483 }
 484
 485 /*
 486 Block decoding order:
 487
 488 dxi: Y-Y
 489 dxic: Y-C-Y
 490 dxic2: Y-C-Y-C
 491
 492 hres,vres,i,i%vres (0 < i < 4)
 493 2x2 0: 0 dxic2
 494 2x2 1: 1 dxi
 495 2x2 2: 0 dxic2
 496 2x2 3: 1 dxi
 497 2x4 0: 0 dxic2
 498 2x4 1: 1 dxi
 499 2x4 2: 2 dxi
 500 2x4 3: 3 dxi
 501 4x2 0: 0 dxic
 502 4x2 1: 1 dxi
 503 4x2 2: 0 dxic
 504 4x2 3: 1 dxi
 505 4x4 0: 0 dxic
 506 4x4 1: 1 dxi
 507 4x4 2: 2 dxi
 508 4x4 3: 3 dxi
 509 */
 510
 511 #define GET_NEXT_INDEX() \
 512 {\
 513     if (index_stream_index >= s->index_stream_size) { \
 514         av_log(s->avctx, AV_LOG_INFO, " help! truemotion1 decoder went out of bounds\n"); \
 515         return; \
 516     } \
 517     index = s->index_stream[index_stream_index++] * 4; \
 518 }
 519
 520 #define APPLY_C_PREDICTOR() \
 521     predictor_pair = s->c_predictor_table[index]; \
 522     horiz_pred += (predictor_pair >> 1); \
 523     if (predictor_pair & 1) { \
 524         GET_NEXT_INDEX() \
 525         if (!index) { \
 526             GET_NEXT_INDEX() \
 527             predictor_pair = s->c_predictor_table[index]; \
 528             horiz_pred += ((predictor_pair >> 1) * 5); \
 529             if (predictor_pair & 1) \
 530                 GET_NEXT_INDEX() \
 531             else \
 532                 index++; \
 533         } \
 534     } else \
 535         index++;
 536
 537 #define APPLY_C_PREDICTOR_24() \
 538     predictor_pair = s->c_predictor_table[index]; \
 539     horiz_pred += (predictor_pair >> 1); \
 540     if (predictor_pair & 1) { \
 541         GET_NEXT_INDEX() \
 542         if (!index) { \
 543             GET_NEXT_INDEX() \
 544             predictor_pair = s->fat_c_predictor_table[index]; \
 545             horiz_pred += (predictor_pair >> 1); \
 546             if (predictor_pair & 1) \
 547                 GET_NEXT_INDEX() \
 548             else \
 549                 index++; \
 550         } \
 551     } else \
 552         index++;
 553
 554
 555 #define APPLY_Y_PREDICTOR() \
 556     predictor_pair = s->y_predictor_table[index]; \
 557     horiz_pred += (predictor_pair >> 1); \
 558     if (predictor_pair & 1) { \
 559         GET_NEXT_INDEX() \
 560         if (!index) { \
 561             GET_NEXT_INDEX() \
 562             predictor_pair = s->y_predictor_table[index]; \
 563             horiz_pred += ((predictor_pair >> 1) * 5); \
 564             if (predictor_pair & 1) \
 565                 GET_NEXT_INDEX() \
 566             else \
 567                 index++; \
 568         } \
 569     } else \
 570         index++;
 571
 572 #define APPLY_Y_PREDICTOR_24() \
 573     predictor_pair = s->y_predictor_table[index]; \
 574     horiz_pred += (predictor_pair >> 1); \
 575     if (predictor_pair & 1) { \
 576         GET_NEXT_INDEX() \
 577         if (!index) { \
 578             GET_NEXT_INDEX() \
 579             predictor_pair = s->fat_y_predictor_table[index]; \
 580             horiz_pred += (predictor_pair >> 1); \
 581             if (predictor_pair & 1) \
 582                 GET_NEXT_INDEX() \
 583             else \
 584                 index++; \
 585         } \
 586     } else \
 587         index++;
 588
 589 #define OUTPUT_PIXEL_PAIR() \
 590     *current_pixel_pair = *vert_pred + horiz_pred; \
 591     *vert_pred++ = *current_pixel_pair++;
 592
 593 static void truemotion1_decode_16bit(TrueMotion1Context *s)
 594 {
 595     int y;
 596     int pixels_left;  /* remaining pixels on this line */
 597     unsigned int predictor_pair;
 598     unsigned int horiz_pred;
 599     unsigned int *vert_pred;
 600     unsigned int *current_pixel_pair;
 601     unsigned char *current_line = s->frame.data[0];
 602     int keyframe = s->flags & FLAG_KEYFRAME;
 603
 604     /* these variables are for managing the stream of macroblock change bits */
 605     const unsigned char *mb_change_bits = s->mb_change_bits;
 606     unsigned char mb_change_byte;
 607     unsigned char mb_change_byte_mask;
 608     int mb_change_index;
 609
 610     /* these variables are for managing the main index stream */
 611     int index_stream_index = 0;  /* yes, the index into the index stream */
 612     int index;
 613
 614     /* clean out the line buffer */
 615     memset(s->vert_pred, 0, s->avctx->width * sizeof(unsigned int));
 616
 617     GET_NEXT_INDEX();
 618
 619     for (y = 0; y < s->avctx->height; y++) {
 620
 621         /* re-init variables for the next line iteration */
 622         horiz_pred = 0;
 623         current_pixel_pair = (unsigned int *)current_line;
 624         vert_pred = s->vert_pred;
 625         mb_change_index = 0;
 626         mb_change_byte = mb_change_bits[mb_change_index++];
 627         mb_change_byte_mask = 0x01;
 628         pixels_left = s->avctx->width;
 629
 630         while (pixels_left > 0) {
 631
 632             if (keyframe || ((mb_change_byte & mb_change_byte_mask) == 0)) {
 633
 634                 switch (y & 3) {
 635                 case 0:
 636                     /* if macroblock width is 2, apply C-Y-C-Y; else
 637                      * apply C-Y-Y */
 638                     if (s->block_width == 2) {
 639                         APPLY_C_PREDICTOR();
 640                         APPLY_Y_PREDICTOR();
 641                         OUTPUT_PIXEL_PAIR();
 642                         APPLY_C_PREDICTOR();
 643                         APPLY_Y_PREDICTOR();
 644                         OUTPUT_PIXEL_PAIR();
 645                     } else {
 646                         APPLY_C_PREDICTOR();
 647                         APPLY_Y_PREDICTOR();
 648                         OUTPUT_PIXEL_PAIR();
 649                         APPLY_Y_PREDICTOR();
 650                         OUTPUT_PIXEL_PAIR();
 651                     }
 652                     break;
 653
 654                 case 1:
 655                 case 3:
 656                     /* always apply 2 Y predictors on these iterations */
 657                     APPLY_Y_PREDICTOR();
 658                     OUTPUT_PIXEL_PAIR();
 659                     APPLY_Y_PREDICTOR();
 660                     OUTPUT_PIXEL_PAIR();
 661                     break;
 662
 663                 case 2:
 664                     /* this iteration might be C-Y-C-Y, Y-Y, or C-Y-Y
 665                      * depending on the macroblock type */
 666                     if (s->block_type == BLOCK_2x2) {
 667                         APPLY_C_PREDICTOR();
 668                         APPLY_Y_PREDICTOR();
 669                         OUTPUT_PIXEL_PAIR();
 670                         APPLY_C_PREDICTOR();
 671                         APPLY_Y_PREDICTOR();
 672                         OUTPUT_PIXEL_PAIR();
 673                     } else if (s->block_type == BLOCK_4x2) {
 674                         APPLY_C_PREDICTOR();
 675                         APPLY_Y_PREDICTOR();
 676                         OUTPUT_PIXEL_PAIR();
 677                         APPLY_Y_PREDICTOR();
 678                         OUTPUT_PIXEL_PAIR();
 679                     } else {
 680                         APPLY_Y_PREDICTOR();
 681                         OUTPUT_PIXEL_PAIR();
 682                         APPLY_Y_PREDICTOR();
 683                         OUTPUT_PIXEL_PAIR();
 684                     }
 685                     break;
 686                 }
 687
 688             } else {
 689
 690                 /* skip (copy) four pixels, but reassign the horizontal
 691                  * predictor */
 692                 *vert_pred++ = *current_pixel_pair++;
 693                 horiz_pred = *current_pixel_pair - *vert_pred;
 694                 *vert_pred++ = *current_pixel_pair++;
 695
 696             }
 697
 698             if (!keyframe) {
 699                 mb_change_byte_mask <<= 1;
 700
 701                 /* next byte */
 702                 if (!mb_change_byte_mask) {
 703                     mb_change_byte = mb_change_bits[mb_change_index++];
 704                     mb_change_byte_mask = 0x01;
 705                 }
 706             }
 707
 708             pixels_left -= 4;
 709         }
 710
 711         /* next change row */
 712         if (((y + 1) & 3) == 0)
 713             mb_change_bits += s->mb_change_bits_row_size;
 714
 715         current_line += s->frame.linesize[0];
 716     }
 717 }
 718
 719 static void truemotion1_decode_24bit(TrueMotion1Context *s)
 720 {
 721     int y;
 722     int pixels_left;  /* remaining pixels on this line */
 723     unsigned int predictor_pair;
 724     unsigned int horiz_pred;
 725     unsigned int *vert_pred;
 726     unsigned int *current_pixel_pair;
 727     unsigned char *current_line = s->frame.data[0];
 728     int keyframe = s->flags & FLAG_KEYFRAME;
 729
 730     /* these variables are for managing the stream of macroblock change bits */
 731     const unsigned char *mb_change_bits = s->mb_change_bits;
 732     unsigned char mb_change_byte;
 733     unsigned char mb_change_byte_mask;
 734     int mb_change_index;
 735
 736     /* these variables are for managing the main index stream */
 737     int index_stream_index = 0;  /* yes, the index into the index stream */
 738     int index;
 739
 740     /* clean out the line buffer */
 741     memset(s->vert_pred, 0, s->avctx->width * sizeof(unsigned int));
 742
 743     GET_NEXT_INDEX();
 744
 745     for (y = 0; y < s->avctx->height; y++) {
 746
 747         /* re-init variables for the next line iteration */
 748         horiz_pred = 0;
 749         current_pixel_pair = (unsigned int *)current_line;
 750         vert_pred = s->vert_pred;
 751         mb_change_index = 0;
 752         mb_change_byte = mb_change_bits[mb_change_index++];
 753         mb_change_byte_mask = 0x01;
 754         pixels_left = s->avctx->width;
 755
 756         while (pixels_left > 0) {
 757
 758             if (keyframe || ((mb_change_byte & mb_change_byte_mask) == 0)) {
 759
 760                 switch (y & 3) {
 761                 case 0:
 762                     /* if macroblock width is 2, apply C-Y-C-Y; else
 763                      * apply C-Y-Y */
 764                     if (s->block_width == 2) {
 765                         APPLY_C_PREDICTOR_24();
 766                         APPLY_Y_PREDICTOR_24();
 767                         OUTPUT_PIXEL_PAIR();
 768                         APPLY_C_PREDICTOR_24();
 769                         APPLY_Y_PREDICTOR_24();
 770                         OUTPUT_PIXEL_PAIR();
 771                     } else {
 772                         APPLY_C_PREDICTOR_24();
 773                         APPLY_Y_PREDICTOR_24();
 774                         OUTPUT_PIXEL_PAIR();
 775                         APPLY_Y_PREDICTOR_24();
 776                         OUTPUT_PIXEL_PAIR();
 777                     }
 778                     break;
 779
 780                 case 1:
 781                 case 3:
 782                     /* always apply 2 Y predictors on these iterations */
 783                     APPLY_Y_PREDICTOR_24();
 784                     OUTPUT_PIXEL_PAIR();
 785                     APPLY_Y_PREDICTOR_24();
 786                     OUTPUT_PIXEL_PAIR();
 787                     break;
 788
 789                 case 2:
 790                     /* this iteration might be C-Y-C-Y, Y-Y, or C-Y-Y
 791                      * depending on the macroblock type */
 792                     if (s->block_type == BLOCK_2x2) {
 793                         APPLY_C_PREDICTOR_24();
 794                         APPLY_Y_PREDICTOR_24();
 795                         OUTPUT_PIXEL_PAIR();
 796                         APPLY_C_PREDICTOR_24();
 797                         APPLY_Y_PREDICTOR_24();
 798                         OUTPUT_PIXEL_PAIR();
 799                     } else if (s->block_type == BLOCK_4x2) {
 800                         APPLY_C_PREDICTOR_24();
 801                         APPLY_Y_PREDICTOR_24();
 802                         OUTPUT_PIXEL_PAIR();
 803                         APPLY_Y_PREDICTOR_24();
 804                         OUTPUT_PIXEL_PAIR();
 805                     } else {
 806                         APPLY_Y_PREDICTOR_24();
 807                         OUTPUT_PIXEL_PAIR();
 808                         APPLY_Y_PREDICTOR_24();
 809                         OUTPUT_PIXEL_PAIR();
 810                     }
 811                     break;
 812                 }
 813
 814             } else {
 815
 816                 /* skip (copy) four pixels, but reassign the horizontal
 817                  * predictor */
 818                 *vert_pred++ = *current_pixel_pair++;
 819                 horiz_pred = *current_pixel_pair - *vert_pred;
 820                 *vert_pred++ = *current_pixel_pair++;
 821
 822             }
 823
 824             if (!keyframe) {
 825                 mb_change_byte_mask <<= 1;
 826
 827                 /* next byte */
 828                 if (!mb_change_byte_mask) {
 829                     mb_change_byte = mb_change_bits[mb_change_index++];
 830                     mb_change_byte_mask = 0x01;
 831                 }
 832             }
 833
 834             pixels_left -= 4;
 835         }
 836
 837         /* next change row */
 838         if (((y + 1) & 3) == 0)
 839             mb_change_bits += s->mb_change_bits_row_size;
 840
 841         current_line += s->frame.linesize[0];
 842     }
 843 }
 844
 845
 846 static int truemotion1_decode_frame(AVCodecContext *avctx,
 847                                     void *data, int *data_size,
 848                                     AVPacket *avpkt)
 849 {
 850     const uint8_t *buf = avpkt->data;
 851     int buf_size = avpkt->size;
 852     TrueMotion1Context *s = avctx->priv_data;
 853
 854     s->buf = buf;
 855     s->size = buf_size;
 856
 857     if (truemotion1_decode_header(s) == -1)
 858         return -1;
 859
 860     s->frame.reference = 1;
 861     s->frame.buffer_hints = FF_BUFFER_HINTS_VALID |
 862         FF_BUFFER_HINTS_PRESERVE | FF_BUFFER_HINTS_REUSABLE;
 863     if (avctx->reget_buffer(avctx, &s->frame) < 0) {
 864         av_log(s->avctx, AV_LOG_ERROR, "get_buffer() failed\n");
 865         return -1;
 866     }
 867
 868     if (compression_types[s->compression].algorithm == ALGO_RGB24H) {
 869         truemotion1_decode_24bit(s);
 870     } else if (compression_types[s->compression].algorithm != ALGO_NOP) {
 871         truemotion1_decode_16bit(s);
 872     }
 873
 874     *data_size = sizeof(AVFrame);
 875     *(AVFrame*)data = s->frame;
 876
 877     /* report that the buffer was completely consumed */
 878     return buf_size;
 879 }
 880
 881 static av_cold int truemotion1_decode_end(AVCodecContext *avctx)
 882 {
 883     TrueMotion1Context *s = avctx->priv_data;
 884
 885     if (s->frame.data[0])
 886         avctx->release_buffer(avctx, &s->frame);
 887
 888     av_free(s->vert_pred);
 889
 890     return 0;
 891 }
 892
 893 AVCodec truemotion1_decoder = {
 894     "truemotion1",
 895     CODEC_TYPE_VIDEO,
 896     CODEC_ID_TRUEMOTION1,
 897     sizeof(TrueMotion1Context),
 898     truemotion1_decode_init,
 899     NULL,
 900     truemotion1_decode_end,
 901     truemotion1_decode_frame,
 902     CODEC_CAP_DR1,
 903     .long_name = NULL_IF_CONFIG_SMALL("Duck TrueMotion 1.0"),
 904 };