git.sesse.net Git - ffmpeg/blob - libavcodec/hnm4video.c

   1 /*
   2  * Cryo Interactive Entertainment HNM4 video decoder
   3  *
   4  * Copyright (c) 2012 David Kment
   5  *
   6  * This file is part of FFmpeg.
   7  *
   8  * FFmpeg is free software; you can redistribute it and/or
   9  * modify it under the terms of the GNU Lesser General Public
  10  * License as published by the Free Software Foundation; either
  11  * version 2.1 of the License, or (at your option) any later version.
  12  *
  13  * FFmpeg is distributed in the hope that it will be useful,
  14  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  15  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  16  * Lesser General Public License for more details.
  17  *
  18  * You should have received a copy of the GNU Lesser General Public
  19  * License along with FFmpeg; if not, write to the Free Software
  20  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
  21  */
  22
  23 #include <string.h>
  24
  25 #include "libavutil/internal.h"
  26 #include "libavutil/intreadwrite.h"
  27 #include "libavutil/mem.h"
  28 #include "avcodec.h"
  29 #include "bytestream.h"
  30 #include "internal.h"
  31
  32 #define HNM4_CHUNK_ID_PL 19536
  33 #define HNM4_CHUNK_ID_IZ 23113
  34 #define HNM4_CHUNK_ID_IU 21833
  35 #define HNM4_CHUNK_ID_SD 17491
  36
  37 typedef struct Hnm4VideoContext {
  38     uint8_t version;
  39     uint16_t width;
  40     uint16_t height;
  41     uint8_t *current;
  42     uint8_t *previous;
  43     uint8_t *buffer1;
  44     uint8_t *buffer2;
  45     uint8_t *processed;
  46     uint32_t palette[256];
  47 } Hnm4VideoContext;
  48
  49 static int getbit(GetByteContext *gb, uint32_t *bitbuf, int *bits)
  50 {
  51     int ret;
  52
  53     if (!*bits) {
  54         *bitbuf = bytestream2_get_le32(gb);
  55         *bits = 32;
  56     }
  57
  58     ret = *bitbuf >> 31;
  59     *bitbuf <<= 1;
  60     (*bits)--;
  61
  62     return ret;
  63 }
  64
  65 static void unpack_intraframe(AVCodecContext *avctx, uint8_t *src,
  66                               uint32_t size)
  67 {
  68     Hnm4VideoContext *hnm = avctx->priv_data;
  69     GetByteContext gb;
  70     uint32_t bitbuf = 0, writeoffset = 0, count = 0;
  71     uint16_t word;
  72     int32_t offset;
  73     int bits = 0;
  74
  75     bytestream2_init(&gb, src, size);
  76
  77     while (bytestream2_tell(&gb) < size) {
  78         if (getbit(&gb, &bitbuf, &bits)) {
  79             if (writeoffset >= hnm->width * hnm->height) {
  80                 av_log(avctx, AV_LOG_ERROR,
  81                        "Attempting to write out of bounds\n");
  82                 break;
  83             }
  84             hnm->current[writeoffset++] = bytestream2_get_byte(&gb);
  85         } else {
  86             if (getbit(&gb, &bitbuf, &bits)) {
  87                 word   = bytestream2_get_le16(&gb);
  88                 count  = word & 0x07;
  89                 offset = (word >> 3) - 0x2000;
  90                 if (!count)
  91                     count = bytestream2_get_byte(&gb);
  92                 if (!count)
  93                     return;
  94             } else {
  95                 count  = getbit(&gb, &bitbuf, &bits) * 2;
  96                 count += getbit(&gb, &bitbuf, &bits);
  97                 offset = bytestream2_get_byte(&gb) - 0x0100;
  98             }
  99             count  += 2;
 100             offset += writeoffset;
 101             if (offset < 0 || offset + count >= hnm->width * hnm->height) {
 102                 av_log(avctx, AV_LOG_ERROR, "Attempting to read out of bounds\n");
 103                 break;
 104             } else if (writeoffset + count >= hnm->width * hnm->height) {
 105                 av_log(avctx, AV_LOG_ERROR,
 106                        "Attempting to write out of bounds\n");
 107                 break;
 108             }
 109             while (count--) {
 110                 hnm->current[writeoffset++] = hnm->current[offset++];
 111             }
 112         }
 113     }
 114 }
 115
 116 static void postprocess_current_frame(AVCodecContext *avctx)
 117 {
 118     Hnm4VideoContext *hnm = avctx->priv_data;
 119     uint32_t x, y, src_x, src_y;
 120
 121     for (y = 0; y < hnm->height; y++) {
 122         src_y = y - (y % 2);
 123         src_x = src_y * hnm->width + (y % 2);
 124         for (x = 0; x < hnm->width; x++) {
 125             hnm->processed[(y * hnm->width) + x] = hnm->current[src_x];
 126             src_x += 2;
 127         }
 128     }
 129 }
 130
 131 static void copy_processed_frame(AVCodecContext *avctx, AVFrame *frame)
 132 {
 133     Hnm4VideoContext *hnm = avctx->priv_data;
 134     uint8_t *src = hnm->processed;
 135     uint8_t *dst = frame->data[0];
 136     int y;
 137
 138     for (y = 0; y < hnm->height; y++) {
 139         memcpy(dst, src, hnm->width);
 140         src += hnm->width;
 141         dst += frame->linesize[0];
 142     }
 143 }
 144
 145 static void decode_interframe_v4(AVCodecContext *avctx, uint8_t *src, uint32_t size)
 146 {
 147     Hnm4VideoContext *hnm = avctx->priv_data;
 148     GetByteContext gb;
 149     uint32_t writeoffset = 0;
 150     int count, left, offset;
 151     uint8_t tag, previous, backline, backward, swap;
 152
 153     bytestream2_init(&gb, src, size);
 154
 155     while (bytestream2_tell(&gb) < size) {
 156         count = bytestream2_peek_byte(&gb) & 0x1F;
 157         if (count == 0) {
 158             tag = bytestream2_get_byte(&gb) & 0xE0;
 159             tag = tag >> 5;
 160
 161             if (tag == 0) {
 162                 if (writeoffset + 2 > hnm->width * hnm->height) {
 163                     av_log(avctx, AV_LOG_ERROR, "writeoffset out of bounds\n");
 164                     break;
 165                 }
 166                 hnm->current[writeoffset++] = bytestream2_get_byte(&gb);
 167                 hnm->current[writeoffset++] = bytestream2_get_byte(&gb);
 168             } else if (tag == 1) {
 169                 writeoffset += bytestream2_get_byte(&gb) * 2;
 170             } else if (tag == 2) {
 171                 count = bytestream2_get_le16(&gb);
 172                 count *= 2;
 173                 writeoffset += count;
 174             } else if (tag == 3) {
 175                 count = bytestream2_get_byte(&gb) * 2;
 176                 if (writeoffset + count > hnm->width * hnm->height) {
 177                     av_log(avctx, AV_LOG_ERROR, "writeoffset out of bounds\n");
 178                     break;
 179                 }
 180                 while (count > 0) {
 181                     hnm->current[writeoffset++] = bytestream2_peek_byte(&gb);
 182                     count--;
 183                 }
 184                 bytestream2_skip(&gb, 1);
 185             } else {
 186                 break;
 187             }
 188             if (writeoffset > hnm->width * hnm->height) {
 189                 av_log(avctx, AV_LOG_ERROR, "writeoffset out of bounds\n");
 190                 break;
 191             }
 192         } else {
 193             previous = bytestream2_peek_byte(&gb) & 0x20;
 194             backline = bytestream2_peek_byte(&gb) & 0x40;
 195             backward = bytestream2_peek_byte(&gb) & 0x80;
 196             bytestream2_skip(&gb, 1);
 197             swap   = bytestream2_peek_byte(&gb) & 0x01;
 198             offset = bytestream2_get_le16(&gb);
 199             offset = (offset >> 1) & 0x7FFF;
 200             offset = writeoffset + (offset * 2) - 0x8000;
 201
 202             left = count;
 203
 204             if (!backward && offset + 2*count > hnm->width * hnm->height) {
 205                 av_log(avctx, AV_LOG_ERROR, "Attempting to read out of bounds\n");
 206                 break;
 207             } else if (backward && offset + 1 >= hnm->width * hnm->height) {
 208                 av_log(avctx, AV_LOG_ERROR, "Attempting to read out of bounds\n");
 209                 break;
 210             } else if (writeoffset + 2*count > hnm->width * hnm->height) {
 211                 av_log(avctx, AV_LOG_ERROR,
 212                        "Attempting to write out of bounds\n");
 213                 break;
 214             }
 215             if(backward) {
 216                 if (offset < (!!backline)*(2 * hnm->width - 1) + 2*(left-1)) {
 217                     av_log(avctx, AV_LOG_ERROR, "Attempting to read out of bounds\n");
 218                     break;
 219                 }
 220             } else {
 221                 if (offset < (!!backline)*(2 * hnm->width - 1)) {
 222                     av_log(avctx, AV_LOG_ERROR, "Attempting to read out of bounds\n");
 223                     break;
 224                 }
 225             }
 226
 227             if (previous) {
 228                 while (left > 0) {
 229                     if (backline) {
 230                         hnm->current[writeoffset++] = hnm->previous[offset - (2 * hnm->width) + 1];
 231                         hnm->current[writeoffset++] = hnm->previous[offset++];
 232                         offset++;
 233                     } else {
 234                         hnm->current[writeoffset++] = hnm->previous[offset++];
 235                         hnm->current[writeoffset++] = hnm->previous[offset++];
 236                     }
 237                     if (backward)
 238                         offset -= 4;
 239                     left--;
 240                 }
 241             } else {
 242                 while (left > 0) {
 243                     if (backline) {
 244                         hnm->current[writeoffset++] = hnm->current[offset - (2 * hnm->width) + 1];
 245                         hnm->current[writeoffset++] = hnm->current[offset++];
 246                         offset++;
 247                     } else {
 248                         hnm->current[writeoffset++] = hnm->current[offset++];
 249                         hnm->current[writeoffset++] = hnm->current[offset++];
 250                     }
 251                     if (backward)
 252                         offset -= 4;
 253                     left--;
 254                 }
 255             }
 256
 257             if (swap) {
 258                 left         = count;
 259                 writeoffset -= count * 2;
 260                 while (left > 0) {
 261                     swap = hnm->current[writeoffset];
 262                     hnm->current[writeoffset] = hnm->current[writeoffset + 1];
 263                     hnm->current[writeoffset + 1] = swap;
 264                     left--;
 265                     writeoffset += 2;
 266                 }
 267             }
 268         }
 269     }
 270 }
 271
 272 static void decode_interframe_v4a(AVCodecContext *avctx, uint8_t *src,
 273                                   uint32_t size)
 274 {
 275     Hnm4VideoContext *hnm = avctx->priv_data;
 276     GetByteContext gb;
 277     uint32_t writeoffset = 0, offset;
 278     uint8_t tag, count, previous, delta;
 279
 280     bytestream2_init(&gb, src, size);
 281
 282     while (bytestream2_tell(&gb) < size) {
 283         count = bytestream2_peek_byte(&gb) & 0x3F;
 284         if (count == 0) {
 285             tag = bytestream2_get_byte(&gb) & 0xC0;
 286             tag = tag >> 6;
 287             if (tag == 0) {
 288                 writeoffset += bytestream2_get_byte(&gb);
 289             } else if (tag == 1) {
 290                 if (writeoffset + hnm->width >= hnm->width * hnm->height) {
 291                     av_log(avctx, AV_LOG_ERROR, "writeoffset out of bounds\n");
 292                     break;
 293                 }
 294                 hnm->current[writeoffset]              = bytestream2_get_byte(&gb);
 295                 hnm->current[writeoffset + hnm->width] = bytestream2_get_byte(&gb);
 296                 writeoffset++;
 297             } else if (tag == 2) {
 298                 writeoffset += hnm->width;
 299             } else if (tag == 3) {
 300                 break;
 301             }
 302             if (writeoffset > hnm->width * hnm->height) {
 303                 av_log(avctx, AV_LOG_ERROR, "writeoffset out of bounds\n");
 304                 break;
 305             }
 306         } else {
 307             delta    = bytestream2_peek_byte(&gb) & 0x80;
 308             previous = bytestream2_peek_byte(&gb) & 0x40;
 309             bytestream2_skip(&gb, 1);
 310
 311             offset  = writeoffset;
 312             offset += bytestream2_get_le16(&gb);
 313
 314             if (delta)
 315                 offset -= 0x10000;
 316
 317             if (offset + hnm->width + count >= hnm->width * hnm->height) {
 318                 av_log(avctx, AV_LOG_ERROR, "Attempting to read out of bounds\n");
 319                 break;
 320             } else if (writeoffset + hnm->width + count >= hnm->width * hnm->height) {
 321                 av_log(avctx, AV_LOG_ERROR, "Attempting to write out of bounds\n");
 322                 break;
 323             }
 324
 325             if (previous) {
 326                 while (count > 0) {
 327                     hnm->current[writeoffset]              = hnm->previous[offset];
 328                     hnm->current[writeoffset + hnm->width] = hnm->previous[offset + hnm->width];
 329                     writeoffset++;
 330                     offset++;
 331                     count--;
 332                 }
 333             } else {
 334                 while (count > 0) {
 335                     hnm->current[writeoffset]              = hnm->current[offset];
 336                     hnm->current[writeoffset + hnm->width] = hnm->current[offset + hnm->width];
 337                     writeoffset++;
 338                     offset++;
 339                     count--;
 340                 }
 341             }
 342         }
 343     }
 344 }
 345
 346 static void hnm_update_palette(AVCodecContext *avctx, uint8_t *src,
 347                                uint32_t size)
 348 {
 349     Hnm4VideoContext *hnm = avctx->priv_data;
 350     GetByteContext gb;
 351     uint8_t start, writeoffset;
 352     uint16_t count;
 353     int eight_bit_colors;
 354
 355     eight_bit_colors = src[7] & 0x80 && hnm->version == 0x4a;
 356
 357     // skip first 8 bytes
 358     bytestream2_init(&gb, src + 8, size - 8);
 359
 360     while (bytestream2_tell(&gb) < size - 8) {
 361         start = bytestream2_get_byte(&gb);
 362         count = bytestream2_get_byte(&gb);
 363         if (start == 255 && count == 255)
 364             break;
 365         if (count == 0)
 366             count = 256;
 367         writeoffset = start;
 368         while (count > 0) {
 369             hnm->palette[writeoffset] = bytestream2_get_be24(&gb);
 370             if (!eight_bit_colors)
 371                 hnm->palette[writeoffset] <<= 2;
 372             count--;
 373             writeoffset++;
 374         }
 375     }
 376 }
 377
 378 static void hnm_flip_buffers(Hnm4VideoContext *hnm)
 379 {
 380     uint8_t *temp;
 381
 382     temp          = hnm->current;
 383     hnm->current  = hnm->previous;
 384     hnm->previous = temp;
 385 }
 386
 387 static int hnm_decode_frame(AVCodecContext *avctx, void *data,
 388                             int *got_frame, AVPacket *avpkt)
 389 {
 390     AVFrame *frame = data;
 391     Hnm4VideoContext *hnm = avctx->priv_data;
 392     int ret;
 393     uint16_t chunk_id;
 394
 395     if (avpkt->size < 8) {
 396         av_log(avctx, AV_LOG_ERROR, "packet too small\n");
 397         return AVERROR_INVALIDDATA;
 398     }
 399
 400     if ((ret = ff_get_buffer(avctx, frame, 0)) < 0)
 401         return ret;
 402
 403     chunk_id = AV_RL16(avpkt->data + 4);
 404
 405     if (chunk_id == HNM4_CHUNK_ID_PL) {
 406         hnm_update_palette(avctx, avpkt->data, avpkt->size);
 407         frame->palette_has_changed = 1;
 408     } else if (chunk_id == HNM4_CHUNK_ID_IZ) {
 409         if (avpkt->size < 12) {
 410             av_log(avctx, AV_LOG_ERROR, "packet too small\n");
 411             return AVERROR_INVALIDDATA;
 412         }
 413         unpack_intraframe(avctx, avpkt->data + 12, avpkt->size - 12);
 414         memcpy(hnm->previous, hnm->current, hnm->width * hnm->height);
 415         if (hnm->version == 0x4a)
 416             memcpy(hnm->processed, hnm->current, hnm->width * hnm->height);
 417         else
 418             postprocess_current_frame(avctx);
 419         copy_processed_frame(avctx, frame);
 420         frame->pict_type = AV_PICTURE_TYPE_I;
 421         frame->key_frame = 1;
 422         memcpy(frame->data[1], hnm->palette, 256 * 4);
 423         *got_frame = 1;
 424     } else if (chunk_id == HNM4_CHUNK_ID_IU) {
 425         if (hnm->version == 0x4a) {
 426             decode_interframe_v4a(avctx, avpkt->data + 8, avpkt->size - 8);
 427             memcpy(hnm->processed, hnm->current, hnm->width * hnm->height);
 428         } else {
 429             decode_interframe_v4(avctx, avpkt->data + 8, avpkt->size - 8);
 430             postprocess_current_frame(avctx);
 431         }
 432         copy_processed_frame(avctx, frame);
 433         frame->pict_type = AV_PICTURE_TYPE_P;
 434         frame->key_frame = 0;
 435         memcpy(frame->data[1], hnm->palette, 256 * 4);
 436         *got_frame = 1;
 437         hnm_flip_buffers(hnm);
 438     } else {
 439         av_log(avctx, AV_LOG_ERROR, "invalid chunk id: %d\n", chunk_id);
 440         return AVERROR_INVALIDDATA;
 441     }
 442
 443     return avpkt->size;
 444 }
 445
 446 static av_cold int hnm_decode_init(AVCodecContext *avctx)
 447 {
 448     Hnm4VideoContext *hnm = avctx->priv_data;
 449
 450     if (avctx->extradata_size < 1) {
 451         av_log(avctx, AV_LOG_ERROR,
 452                "Extradata missing, decoder requires version number\n");
 453         return AVERROR_INVALIDDATA;
 454     }
 455
 456     hnm->version   = avctx->extradata[0];
 457     avctx->pix_fmt = AV_PIX_FMT_PAL8;
 458     hnm->width     = avctx->width;
 459     hnm->height    = avctx->height;
 460     hnm->buffer1   = av_mallocz(avctx->width * avctx->height);
 461     hnm->buffer2   = av_mallocz(avctx->width * avctx->height);
 462     hnm->processed = av_mallocz(avctx->width * avctx->height);
 463
 464     if (   !hnm->buffer1 || !hnm->buffer2 || !hnm->processed
 465         || avctx->width * avctx->height == 0
 466         || avctx->height % 2) {
 467         av_log(avctx, AV_LOG_ERROR, "av_mallocz() failed\n");
 468         av_freep(&hnm->buffer1);
 469         av_freep(&hnm->buffer2);
 470         av_freep(&hnm->processed);
 471         return AVERROR(ENOMEM);
 472     }
 473
 474     hnm->current  = hnm->buffer1;
 475     hnm->previous = hnm->buffer2;
 476
 477     return 0;
 478 }
 479
 480 static av_cold int hnm_decode_end(AVCodecContext *avctx)
 481 {
 482     Hnm4VideoContext *hnm = avctx->priv_data;
 483
 484     av_freep(&hnm->buffer1);
 485     av_freep(&hnm->buffer2);
 486     av_freep(&hnm->processed);
 487
 488     return 0;
 489 }
 490
 491 AVCodec ff_hnm4_video_decoder = {
 492     .name           = "hnm4video",
 493     .long_name      = NULL_IF_CONFIG_SMALL("HNM 4 video"),
 494     .type           = AVMEDIA_TYPE_VIDEO,
 495     .id             = AV_CODEC_ID_HNM4_VIDEO,
 496     .priv_data_size = sizeof(Hnm4VideoContext),
 497     .init           = hnm_decode_init,
 498     .close          = hnm_decode_end,
 499     .decode         = hnm_decode_frame,
 500     .capabilities   = CODEC_CAP_DR1,
 501 };