libavcodec/truemotion1.c

   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
   7  * License as published by the Free Software Foundation; either
   8  * version 2 of the License, or (at your option) any later version.
   9  *
  10  * 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
  16  * License along with this library; if not, write to the Free Software
  17  * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
  18  */
  19
  20 /**
  21  * @file truemotion1.c
  22  * Duck TrueMotion v1 Video Decoder by
  23  * Alex Beregszaszi (alex@fsn.hu) and
  24  * Mike Melanson (melanson@pcisys.net)
  25  *
  26  * The TrueMotion v1 decoder presently only decodes 16-bit TM1 data and
  27  * 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 #define LE_16(x)  ((((uint8_t*)(x))[1] << 8) | ((uint8_t*)(x))[0])
  42
  43 typedef struct TrueMotion1Context {
  44     AVCodecContext *avctx;
  45     AVFrame frame;
  46     AVFrame prev_frame;
  47
  48     unsigned char *buf;
  49     int size;
  50
  51     unsigned char *mb_change_bits;
  52     int mb_change_bits_row_size;
  53     unsigned char *index_stream;
  54     int index_stream_size;
  55
  56     int flags;
  57     int x, y, w, h;
  58
  59     uint32_t y_predictor_table[1024];
  60     uint32_t c_predictor_table[1024];
  61
  62     int compression;
  63     int block_type;
  64     int block_width;
  65     int block_height;
  66
  67     int16_t *ydt;
  68     int16_t *cdt;
  69     int16_t *fat_ydt;
  70     int16_t *fat_cdt;
  71
  72     int last_deltaset, last_vectable;
  73
  74     unsigned int *vert_pred;
  75
  76 } TrueMotion1Context;
  77
  78 #define FLAG_SPRITE         32
  79 #define FLAG_KEYFRAME       16
  80 #define FLAG_INTERFRAME      8
  81 #define FLAG_INTERPOLATED    4
  82
  83 struct frame_header {
  84     uint8_t header_size;
  85     uint8_t compression;
  86     uint8_t deltaset;
  87     uint8_t vectable;
  88     uint16_t ysize;
  89     uint16_t xsize;
  90     uint16_t checksum;
  91     uint8_t version;
  92     uint8_t header_type;
  93     uint8_t flags;
  94     uint8_t control;
  95     uint16_t xoffset;
  96     uint16_t yoffset;
  97     uint16_t width;
  98     uint16_t height;
  99 };
 100
 101 #define ALGO_NOP        0
 102 #define ALGO_RGB16V     1
 103 #define ALGO_RGB16H     2
 104 #define ALGO_RGB24H     3
 105
 106 /* these are the various block sizes that can occupy a 4x4 block */
 107 #define BLOCK_2x2  0
 108 #define BLOCK_2x4  1
 109 #define BLOCK_4x2  2
 110 #define BLOCK_4x4  3
 111
 112 typedef struct comp_types {
 113     int algorithm;
 114     int block_width;
 115     int block_height;
 116     int block_type;
 117 } comp_types;
 118
 119 /* { valid for metatype }, algorithm, num of deltas, horiz res, vert res */
 120 static comp_types compression_types[17] = {
 121     { ALGO_NOP,    0, 0, 0 },
 122
 123     { ALGO_RGB16V, 4, 4, BLOCK_4x4 },
 124     { ALGO_RGB16H, 4, 4, BLOCK_4x4 },
 125     { ALGO_RGB16V, 4, 2, BLOCK_4x2 },
 126     { ALGO_RGB16H, 4, 2, BLOCK_4x2 },
 127
 128     { ALGO_RGB16V, 2, 4, BLOCK_2x4 },
 129     { ALGO_RGB16H, 2, 4, BLOCK_2x4 },
 130     { ALGO_RGB16V, 2, 2, BLOCK_2x2 },
 131     { ALGO_RGB16H, 2, 2, BLOCK_2x2 },
 132
 133     { ALGO_NOP,    4, 4, BLOCK_4x4 },
 134     { ALGO_RGB24H, 4, 4, BLOCK_4x4 },
 135     { ALGO_NOP,    4, 2, BLOCK_4x2 },
 136     { ALGO_RGB24H, 4, 2, BLOCK_4x2 },
 137
 138     { ALGO_NOP,    2, 4, BLOCK_2x4 },
 139     { ALGO_RGB24H, 2, 4, BLOCK_2x4 },
 140     { ALGO_NOP,    2, 2, BLOCK_2x2 },
 141     { ALGO_RGB24H, 2, 2, BLOCK_2x2 }
 142 };
 143
 144 static void select_delta_tables(TrueMotion1Context *s, int delta_table_index)
 145 {
 146     int i;
 147
 148     if (delta_table_index > 3)
 149         return;
 150
 151     s->ydt = ydts[delta_table_index];
 152     s->cdt = cdts[delta_table_index];
 153     s->fat_ydt = fat_ydts[delta_table_index];
 154     s->fat_cdt = fat_cdts[delta_table_index];
 155
 156     /* Y skinny deltas need to be halved for some reason; maybe the
 157      * skinny Y deltas should be modified */
 158     for (i = 0; i < 8; i++)
 159     {
 160         /* drop the lsb before dividing by 2-- net effect: round down
 161          * when dividing a negative number (e.g., -3/2 = -2, not -1) */
 162         s->ydt[i] &= 0xFFFE;
 163         s->ydt[i] /= 2;
 164     }
 165 }
 166
 167 static int make_ydt_entry(int p1, int p2, int16_t *ydt)
 168 {
 169     int lo, hi;
 170
 171     lo = ydt[p1];
 172     lo += (lo << 5) + (lo << 10);
 173     hi = ydt[p2];
 174     hi += (hi << 5) + (hi << 10);
 175     return ((lo + (hi << 16)) << 1);
 176 }
 177
 178 static int make_cdt_entry(int p1, int p2, int16_t *cdt)
 179 {
 180     int r, b, lo;
 181
 182     b = cdt[p2];
 183     r = cdt[p1] << 10;
 184     lo = b + r;
 185     return ((lo + (lo << 16)) << 1);
 186 }
 187
 188 static void gen_vector_table(TrueMotion1Context *s, uint8_t *sel_vector_table)
 189 {
 190     int len, i, j;
 191     unsigned char delta_pair;
 192
 193     for (i = 0; i < 1024; i += 4)
 194     {
 195         len = *sel_vector_table++ / 2;
 196         for (j = 0; j < len; j++)
 197         {
 198             delta_pair = *sel_vector_table++;
 199             s->y_predictor_table[i+j] = 0xfffffffe &
 200                 make_ydt_entry(delta_pair >> 4, delta_pair & 0xf, s->ydt);
 201             s->c_predictor_table[i+j] = 0xfffffffe &
 202                 make_cdt_entry(delta_pair >> 4, delta_pair & 0xf, s->cdt);
 203         }
 204         s->y_predictor_table[i+(j-1)] |= 1;
 205         s->c_predictor_table[i+(j-1)] |= 1;
 206     }
 207 }
 208
 209 /* Returns the number of bytes consumed from the bytestream. Returns -1 if
 210  * there was an error while decoding the header */
 211 static int truemotion1_decode_header(TrueMotion1Context *s)
 212 {
 213     int i;
 214     struct frame_header header;
 215     uint8_t header_buffer[128];  /* logical maximum size of the header */
 216     uint8_t *sel_vector_table;
 217
 218     /* There is 1 change bit per 4 pixels, so each change byte represents
 219      * 32 pixels; divide width by 4 to obtain the number of change bits and
 220      * then round up to the nearest byte. */
 221     s->mb_change_bits_row_size = ((s->avctx->width >> 2) + 7) >> 3;
 222
 223     header.header_size = ((s->buf[0] >> 5) | (s->buf[0] << 3)) & 0x7f;
 224     if (s->buf[0] < 0x10)
 225     {
 226         printf("invalid header size\n");
 227         return -1;
 228     }
 229
 230     /* unscramble the header bytes with a XOR operation */
 231     memset(header_buffer, 0, 128);
 232     for (i = 1; i < header.header_size; i++)
 233     header_buffer[i - 1] = s->buf[i] ^ s->buf[i + 1];
 234     header.compression = header_buffer[0];
 235     header.deltaset = header_buffer[1];
 236     header.vectable = header_buffer[2];
 237     header.ysize = LE_16(&header_buffer[3]);
 238     header.xsize = LE_16(&header_buffer[5]);
 239     header.checksum = LE_16(&header_buffer[7]);
 240     header.version = header_buffer[9];
 241     header.header_type = header_buffer[10];
 242     header.flags = header_buffer[11];
 243     header.control = header_buffer[12];
 244
 245     /* Version 2 */
 246     if (header.version >= 2)
 247     {
 248         if (header.header_type > 3)
 249         {
 250             av_log(s->avctx, AV_LOG_ERROR, "truemotion1: invalid header type\n");
 251             return -1;
 252         } else if ((header.header_type == 2) || (header.header_type == 3)) {
 253             s->flags = header.flags;
 254             if (!(s->flags & FLAG_INTERFRAME))
 255                 s->flags |= FLAG_KEYFRAME;
 256         } else
 257             s->flags = FLAG_KEYFRAME;
 258     } else /* Version 1 */
 259         s->flags = FLAG_KEYFRAME;
 260
 261     if (s->flags & FLAG_SPRITE) {
 262         s->w = header.width;
 263         s->h = header.height;
 264         s->x = header.xoffset;
 265         s->y = header.yoffset;
 266     } else {
 267         s->w = header.xsize;
 268         s->h = header.ysize;
 269         if (header.header_type < 2) {
 270             if ((s->w < 213) && (s->h >= 176))
 271                 s->flags |= FLAG_INTERPOLATED;
 272         }
 273     }
 274
 275     if (header.compression > 17) {
 276         printf("invalid compression type (%d)\n", header.compression);
 277         return -1;
 278     }
 279
 280     if ((header.deltaset != s->last_deltaset) ||
 281         (header.vectable != s->last_vectable))
 282         select_delta_tables(s, header.deltaset);
 283
 284     if ((header.compression & 1) && header.header_type)
 285         sel_vector_table = pc_tbl2;
 286     else {
 287         if (header.vectable < 4)
 288             sel_vector_table = tables[header.vectable - 1];
 289         else {
 290             printf("invalid vector table id (%d)\n", header.vectable);
 291             return -1;
 292         }
 293     }
 294
 295     if ((header.deltaset != s->last_deltaset) || (header.vectable != s->last_vectable))
 296     {
 297         if (compression_types[header.compression].algorithm == ALGO_RGB24H)
 298         {
 299             printf("24bit compression not yet supported\n");
 300         }
 301         else
 302             gen_vector_table(s, sel_vector_table);
 303     }
 304
 305     /* set up pointers to the other key data chunks */
 306     s->mb_change_bits = s->buf + header.header_size;
 307     if (s->flags & FLAG_KEYFRAME) {
 308         /* no change bits specified for a keyframe; only index bytes */
 309         s->index_stream = s->mb_change_bits;
 310     } else {
 311         /* one change bit per 4x4 block */
 312         s->index_stream = s->mb_change_bits +
 313             (s->mb_change_bits_row_size * (s->avctx->height >> 2));
 314     }
 315     s->index_stream_size = s->size - (s->index_stream - s->buf);
 316
 317     s->last_deltaset = header.deltaset;
 318     s->last_vectable = header.vectable;
 319     s->compression = header.compression;
 320     s->block_width = compression_types[header.compression].block_width;
 321     s->block_height = compression_types[header.compression].block_height;
 322     s->block_type = compression_types[header.compression].block_type;
 323
 324     return header.header_size;
 325 }
 326
 327 static int truemotion1_decode_init(AVCodecContext *avctx)
 328 {
 329     TrueMotion1Context *s = (TrueMotion1Context *)avctx->priv_data;
 330
 331     s->avctx = avctx;
 332
 333     avctx->pix_fmt = PIX_FMT_RGB555;
 334     avctx->has_b_frames = 0;
 335     s->frame.data[0] = s->prev_frame.data[0] = NULL;
 336
 337     /* there is a vertical predictor for each pixel in a line; each vertical
 338      * predictor is 0 to start with */
 339     s->vert_pred =
 340         (unsigned int *)av_malloc(s->avctx->width * sizeof(unsigned short));
 341
 342     return 0;
 343 }
 344
 345 #define GET_NEXT_INDEX() \
 346 {\
 347     if (index_stream_index >= s->index_stream_size) { \
 348         printf (" help! truemotion1 decoder went out of bounds\n"); \
 349         return; \
 350     } \
 351     index = s->index_stream[index_stream_index++] * 4; \
 352 }
 353
 354 #define APPLY_C_PREDICTOR() \
 355     predictor_pair = s->c_predictor_table[index]; \
 356     horiz_pred += (predictor_pair >> 1); \
 357     if (predictor_pair & 1) { \
 358         GET_NEXT_INDEX() \
 359         if (!index) { \
 360             GET_NEXT_INDEX() \
 361             predictor_pair = s->c_predictor_table[index]; \
 362             horiz_pred += ((predictor_pair >> 1) * 5); \
 363             if (predictor_pair & 1) \
 364                 GET_NEXT_INDEX() \
 365             else \
 366                 index++; \
 367         } \
 368     } else \
 369         index++;
 370
 371 #define APPLY_Y_PREDICTOR() \
 372     predictor_pair = s->y_predictor_table[index]; \
 373     horiz_pred += (predictor_pair >> 1); \
 374     if (predictor_pair & 1) { \
 375         GET_NEXT_INDEX() \
 376         if (!index) { \
 377             GET_NEXT_INDEX() \
 378             predictor_pair = s->y_predictor_table[index]; \
 379             horiz_pred += ((predictor_pair >> 1) * 5); \
 380             if (predictor_pair & 1) \
 381                 GET_NEXT_INDEX() \
 382             else \
 383                 index++; \
 384         } \
 385     } else \
 386         index++;
 387
 388 #define OUTPUT_PIXEL_PAIR() \
 389     *current_pixel_pair = *vert_pred + horiz_pred; \
 390     *vert_pred++ = *current_pixel_pair++; \
 391     prev_pixel_pair++;
 392
 393 static void truemotion1_decode_16bit(TrueMotion1Context *s)
 394 {
 395     int y;
 396     int pixels_left;  /* remaining pixels on this line */
 397     unsigned int predictor_pair;
 398     unsigned int horiz_pred;
 399     unsigned int *vert_pred;
 400     unsigned int *current_pixel_pair;
 401     unsigned int *prev_pixel_pair;
 402     unsigned char *current_line = s->frame.data[0];
 403     unsigned char *prev_line = s->prev_frame.data[0];
 404     int keyframe = s->flags & FLAG_KEYFRAME;
 405
 406     /* these variables are for managing the stream of macroblock change bits */
 407     unsigned char *mb_change_bits = s->mb_change_bits;
 408     unsigned char mb_change_byte;
 409     unsigned char mb_change_byte_mask;
 410     int mb_change_index;
 411
 412     /* these variables are for managing the main index stream */
 413     int index_stream_index = 0;  /* yes, the index into the index stream */
 414     int index;
 415
 416     /* clean out the line buffer */
 417     memset(s->vert_pred, 0, s->avctx->width * sizeof(unsigned short));
 418
 419     GET_NEXT_INDEX();
 420
 421     for (y = 0; y < s->avctx->height; y++) {
 422
 423         /* re-init variables for the next line iteration */
 424         horiz_pred = 0;
 425         current_pixel_pair = (unsigned int *)current_line;
 426         prev_pixel_pair = (unsigned int *)prev_line;
 427         vert_pred = s->vert_pred;
 428         mb_change_index = 0;
 429         mb_change_byte = mb_change_bits[mb_change_index++];
 430         mb_change_byte_mask = 0x01;
 431         pixels_left = s->avctx->width;
 432
 433         while (pixels_left > 0) {
 434
 435             if (keyframe || ((mb_change_byte & mb_change_byte_mask) == 0)) {
 436
 437                 switch (y & 3) {
 438                 case 0:
 439                     /* if macroblock width is 2, apply C-Y-C-Y; else
 440                      * apply C-Y-Y */
 441                     if ((s->block_type == BLOCK_2x2) ||
 442                         (s->block_type == BLOCK_2x4)) {
 443                         APPLY_C_PREDICTOR();
 444                         APPLY_Y_PREDICTOR();
 445                         OUTPUT_PIXEL_PAIR();
 446                         APPLY_C_PREDICTOR();
 447                         APPLY_Y_PREDICTOR();
 448                         OUTPUT_PIXEL_PAIR();
 449                     } else {
 450                         APPLY_C_PREDICTOR();
 451                         APPLY_Y_PREDICTOR();
 452                         OUTPUT_PIXEL_PAIR();
 453                         APPLY_Y_PREDICTOR();
 454                         OUTPUT_PIXEL_PAIR();
 455                     }
 456                     break;
 457
 458                 case 1:
 459                 case 3:
 460                     /* always apply 2 Y predictors on these iterations */
 461                     APPLY_Y_PREDICTOR();
 462                     OUTPUT_PIXEL_PAIR();
 463                     APPLY_Y_PREDICTOR();
 464                     OUTPUT_PIXEL_PAIR();
 465                     break;
 466
 467                 case 2:
 468                     /* this iteration might be C-Y-C-Y, Y-Y, or C-Y-Y
 469                      * depending on the macroblock type */
 470                     if (s->block_type == BLOCK_2x2) {
 471                         APPLY_C_PREDICTOR();
 472                         APPLY_Y_PREDICTOR();
 473                         OUTPUT_PIXEL_PAIR();
 474                         APPLY_C_PREDICTOR();
 475                         APPLY_Y_PREDICTOR();
 476                         OUTPUT_PIXEL_PAIR();
 477                     } else if (s->block_type == BLOCK_4x2) {
 478                         APPLY_C_PREDICTOR();
 479                         APPLY_Y_PREDICTOR();
 480                         OUTPUT_PIXEL_PAIR();
 481                         APPLY_Y_PREDICTOR();
 482                         OUTPUT_PIXEL_PAIR();
 483                     } else {
 484                         APPLY_Y_PREDICTOR();
 485                         OUTPUT_PIXEL_PAIR();
 486                         APPLY_Y_PREDICTOR();
 487                         OUTPUT_PIXEL_PAIR();
 488                     }
 489                     break;
 490                 }
 491
 492             } else {
 493
 494                 /* skip (copy) four pixels, but reassign the horizontal
 495                  * predictor */
 496                 *current_pixel_pair = *prev_pixel_pair++;
 497                 *vert_pred++ = *current_pixel_pair++;
 498                 *current_pixel_pair = *prev_pixel_pair++;
 499                 horiz_pred = *current_pixel_pair - *vert_pred;
 500                 *vert_pred++ = *current_pixel_pair++;
 501
 502             }
 503
 504             if (!keyframe) {
 505                 mb_change_byte_mask <<= 1;
 506
 507                 /* next byte */
 508                 if (!mb_change_byte_mask) {
 509                     mb_change_byte = mb_change_bits[mb_change_index++];
 510                     mb_change_byte_mask = 0x01;
 511                 }
 512             }
 513
 514             pixels_left -= 4;
 515         }
 516
 517         /* next change row */
 518         if (((y + 1) & 3) == 0)
 519             mb_change_bits += s->mb_change_bits_row_size;
 520
 521         current_line += s->frame.linesize[0];
 522         prev_line += s->prev_frame.linesize[0];
 523     }
 524 }
 525
 526 static int truemotion1_decode_frame(AVCodecContext *avctx,
 527                                     void *data, int *data_size,
 528                                     uint8_t *buf, int buf_size)
 529 {
 530     TrueMotion1Context *s = (TrueMotion1Context *)avctx->priv_data;
 531
 532     s->buf = buf;
 533     s->size = buf_size;
 534
 535     s->frame.reference = 1;
 536     if (avctx->get_buffer(avctx, &s->frame) < 0) {
 537         fprintf(stderr, "truemotion1: get_buffer() failed\n");
 538         return -1;
 539     }
 540
 541     /* no supplementary picture */
 542     if (buf_size == 0)
 543         return 0;
 544
 545     *data_size = 0;
 546
 547     if (truemotion1_decode_header(s) == -1)
 548         return -1;
 549
 550     /* check for a do-nothing frame and copy the previous frame */
 551     if (compression_types[s->compression].algorithm == ALGO_NOP)
 552     {
 553         memcpy(s->frame.data[0], s->prev_frame.data[0],
 554             s->frame.linesize[0] * s->avctx->height);
 555     } else if (compression_types[s->compression].algorithm == ALGO_RGB24H) {
 556         printf ("  24-bit Duck TrueMotion decoding not yet implemented\n");
 557     } else {
 558         truemotion1_decode_16bit(s);
 559     }
 560
 561     if (s->prev_frame.data[0])
 562         avctx->release_buffer(avctx, &s->prev_frame);
 563
 564     /* shuffle frames */
 565     s->prev_frame = s->frame;
 566
 567     *data_size = sizeof(AVFrame);
 568     *(AVFrame*)data = s->frame;
 569
 570     /* report that the buffer was completely consumed */
 571     return buf_size;
 572 }
 573
 574 static int truemotion1_decode_end(AVCodecContext *avctx)
 575 {
 576     TrueMotion1Context *s = (TrueMotion1Context *)avctx->priv_data;
 577
 578     /* release the last frame */
 579     if (s->prev_frame.data[0])
 580         avctx->release_buffer(avctx, &s->prev_frame);
 581
 582     av_free(s->vert_pred);
 583
 584     return 0;
 585 }
 586
 587 AVCodec truemotion1_decoder = {
 588     "truemotion1",
 589     CODEC_TYPE_VIDEO,
 590     CODEC_ID_TRUEMOTION1,
 591     sizeof(TrueMotion1Context),
 592     truemotion1_decode_init,
 593     NULL,
 594     truemotion1_decode_end,
 595     truemotion1_decode_frame,
 596     CODEC_CAP_DR1,
 597 };