libavcodec/dfa.c

   1 /*
   2  * Chronomaster DFA Video Decoder
   3  * Copyright (c) 2011 Konstantin Shishkov
   4  * based on work by Vladimir "VAG" Gneushev
   5  *
   6  * This file is part of Libav.
   7  *
   8  * Libav 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  * Libav 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 Libav; if not, write to the Free Software
  20  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
  21  */
  22
  23 #include <inttypes.h>
  24
  25 #include "avcodec.h"
  26 #include "bytestream.h"
  27 #include "internal.h"
  28
  29 #include "libavutil/imgutils.h"
  30 #include "libavutil/mem.h"
  31
  32 typedef struct DfaContext {
  33     uint32_t pal[256];
  34     uint8_t *frame_buf;
  35 } DfaContext;
  36
  37 static av_cold int dfa_decode_init(AVCodecContext *avctx)
  38 {
  39     DfaContext *s = avctx->priv_data;
  40     int ret;
  41
  42     avctx->pix_fmt = AV_PIX_FMT_PAL8;
  43
  44     if ((ret = av_image_check_size(avctx->width, avctx->height, 0, avctx)) < 0)
  45         return ret;
  46
  47     s->frame_buf = av_mallocz(avctx->width * avctx->height);
  48     if (!s->frame_buf)
  49         return AVERROR(ENOMEM);
  50
  51     return 0;
  52 }
  53
  54 static int decode_copy(GetByteContext *gb, uint8_t *frame, int width, int height)
  55 {
  56     const int size = width * height;
  57
  58     if (bytestream2_get_buffer(gb, frame, size) != size)
  59         return AVERROR_INVALIDDATA;
  60     return 0;
  61 }
  62
  63 static int decode_tsw1(GetByteContext *gb, uint8_t *frame, int width, int height)
  64 {
  65     const uint8_t *frame_start = frame;
  66     const uint8_t *frame_end   = frame + width * height;
  67     int mask = 0x10000, bitbuf = 0;
  68     int v, count, segments;
  69     unsigned offset;
  70
  71     segments = bytestream2_get_le32(gb);
  72     offset   = bytestream2_get_le32(gb);
  73     if (frame_end - frame <= offset)
  74         return AVERROR_INVALIDDATA;
  75     frame += offset;
  76     while (segments--) {
  77         if (bytestream2_get_bytes_left(gb) < 2)
  78             return AVERROR_INVALIDDATA;
  79         if (mask == 0x10000) {
  80             bitbuf = bytestream2_get_le16u(gb);
  81             mask = 1;
  82         }
  83         if (frame_end - frame < 2)
  84             return AVERROR_INVALIDDATA;
  85         if (bitbuf & mask) {
  86             v = bytestream2_get_le16(gb);
  87             offset = (v & 0x1FFF) << 1;
  88             count = ((v >> 13) + 2) << 1;
  89             if (frame - frame_start < offset || frame_end - frame < count)
  90                 return AVERROR_INVALIDDATA;
  91             av_memcpy_backptr(frame, offset, count);
  92             frame += count;
  93         } else {
  94             *frame++ = bytestream2_get_byte(gb);
  95             *frame++ = bytestream2_get_byte(gb);
  96         }
  97         mask <<= 1;
  98     }
  99
 100     return 0;
 101 }
 102
 103 static int decode_dsw1(GetByteContext *gb, uint8_t *frame, int width, int height)
 104 {
 105     const uint8_t *frame_start = frame;
 106     const uint8_t *frame_end   = frame + width * height;
 107     int mask = 0x10000, bitbuf = 0;
 108     int v, offset, count, segments;
 109
 110     segments = bytestream2_get_le16(gb);
 111     while (segments--) {
 112         if (bytestream2_get_bytes_left(gb) < 2)
 113             return AVERROR_INVALIDDATA;
 114         if (mask == 0x10000) {
 115             bitbuf = bytestream2_get_le16u(gb);
 116             mask = 1;
 117         }
 118         if (frame_end - frame < 2)
 119             return AVERROR_INVALIDDATA;
 120         if (bitbuf & mask) {
 121             v = bytestream2_get_le16(gb);
 122             offset = (v & 0x1FFF) << 1;
 123             count = ((v >> 13) + 2) << 1;
 124             if (frame - frame_start < offset || frame_end - frame < count)
 125                 return AVERROR_INVALIDDATA;
 126             av_memcpy_backptr(frame, offset, count);
 127             frame += count;
 128         } else if (bitbuf & (mask << 1)) {
 129             frame += bytestream2_get_le16(gb);
 130         } else {
 131             *frame++ = bytestream2_get_byte(gb);
 132             *frame++ = bytestream2_get_byte(gb);
 133         }
 134         mask <<= 2;
 135     }
 136
 137     return 0;
 138 }
 139
 140 static int decode_dds1(GetByteContext *gb, uint8_t *frame, int width, int height)
 141 {
 142     const uint8_t *frame_start = frame;
 143     const uint8_t *frame_end   = frame + width * height;
 144     int mask = 0x10000, bitbuf = 0;
 145     int i, v, offset, count, segments;
 146
 147     if ((width | height) & 1)
 148         return AVERROR_INVALIDDATA;
 149     segments = bytestream2_get_le16(gb);
 150     while (segments--) {
 151         if (bytestream2_get_bytes_left(gb) < 2)
 152             return AVERROR_INVALIDDATA;
 153         if (mask == 0x10000) {
 154             bitbuf = bytestream2_get_le16u(gb);
 155             mask = 1;
 156         }
 157
 158         if (bitbuf & mask) {
 159             v = bytestream2_get_le16(gb);
 160             offset = (v & 0x1FFF) << 2;
 161             count = ((v >> 13) + 2) << 1;
 162             if (frame - frame_start < offset || frame_end - frame < count*2 + width)
 163                 return AVERROR_INVALIDDATA;
 164             for (i = 0; i < count; i++) {
 165                 frame[0] = frame[1] =
 166                 frame[width] = frame[width + 1] = frame[-offset];
 167
 168                 frame += 2;
 169             }
 170         } else if (bitbuf & (mask << 1)) {
 171             v = bytestream2_get_le16(gb)*2;
 172             if (frame - frame_end < v)
 173                 return AVERROR_INVALIDDATA;
 174             frame += v;
 175         } else {
 176             if (width < 4 || frame_end - frame < width + 4)
 177                 return AVERROR_INVALIDDATA;
 178             frame[0] = frame[1] =
 179             frame[width] = frame[width + 1] =  bytestream2_get_byte(gb);
 180             frame += 2;
 181             frame[0] = frame[1] =
 182             frame[width] = frame[width + 1] =  bytestream2_get_byte(gb);
 183             frame += 2;
 184         }
 185         mask <<= 2;
 186     }
 187
 188     return 0;
 189 }
 190
 191 static int decode_bdlt(GetByteContext *gb, uint8_t *frame, int width, int height)
 192 {
 193     uint8_t *line_ptr;
 194     int count, lines, segments;
 195
 196     count = bytestream2_get_le16(gb);
 197     if (count >= height)
 198         return AVERROR_INVALIDDATA;
 199     frame += width * count;
 200     lines = bytestream2_get_le16(gb);
 201     if (count + lines > height)
 202         return AVERROR_INVALIDDATA;
 203
 204     while (lines--) {
 205         if (bytestream2_get_bytes_left(gb) < 1)
 206             return AVERROR_INVALIDDATA;
 207         line_ptr = frame;
 208         frame += width;
 209         segments = bytestream2_get_byteu(gb);
 210         while (segments--) {
 211             if (frame - line_ptr <= bytestream2_peek_byte(gb))
 212                 return AVERROR_INVALIDDATA;
 213             line_ptr += bytestream2_get_byte(gb);
 214             count = (int8_t)bytestream2_get_byte(gb);
 215             if (count >= 0) {
 216                 if (frame - line_ptr < count)
 217                     return AVERROR_INVALIDDATA;
 218                 if (bytestream2_get_buffer(gb, line_ptr, count) != count)
 219                     return AVERROR_INVALIDDATA;
 220             } else {
 221                 count = -count;
 222                 if (frame - line_ptr < count)
 223                     return AVERROR_INVALIDDATA;
 224                 memset(line_ptr, bytestream2_get_byte(gb), count);
 225             }
 226             line_ptr += count;
 227         }
 228     }
 229
 230     return 0;
 231 }
 232
 233 static int decode_wdlt(GetByteContext *gb, uint8_t *frame, int width, int height)
 234 {
 235     const uint8_t *frame_end   = frame + width * height;
 236     uint8_t *line_ptr;
 237     int count, i, v, lines, segments;
 238     int y = 0;
 239
 240     lines = bytestream2_get_le16(gb);
 241     if (lines > height)
 242         return AVERROR_INVALIDDATA;
 243
 244     while (lines--) {
 245         if (bytestream2_get_bytes_left(gb) < 2)
 246             return AVERROR_INVALIDDATA;
 247         segments = bytestream2_get_le16u(gb);
 248         while ((segments & 0xC000) == 0xC000) {
 249             unsigned skip_lines = -(int16_t)segments;
 250             unsigned delta = -((int16_t)segments * width);
 251             if (frame_end - frame <= delta || y + lines + skip_lines > height)
 252                 return AVERROR_INVALIDDATA;
 253             frame    += delta;
 254             y        += skip_lines;
 255             segments = bytestream2_get_le16(gb);
 256         }
 257         if (segments & 0x8000) {
 258             frame[width - 1] = segments & 0xFF;
 259             segments = bytestream2_get_le16(gb);
 260         }
 261         line_ptr = frame;
 262         if (frame_end - frame < width)
 263             return AVERROR_INVALIDDATA;
 264         frame += width;
 265         y++;
 266         while (segments--) {
 267             if (frame - line_ptr <= bytestream2_peek_byte(gb))
 268                 return AVERROR_INVALIDDATA;
 269             line_ptr += bytestream2_get_byte(gb);
 270             count = (int8_t)bytestream2_get_byte(gb);
 271             if (count >= 0) {
 272                 if (frame - line_ptr < count * 2)
 273                     return AVERROR_INVALIDDATA;
 274                 if (bytestream2_get_buffer(gb, line_ptr, count * 2) != count * 2)
 275                     return AVERROR_INVALIDDATA;
 276                 line_ptr += count * 2;
 277             } else {
 278                 count = -count;
 279                 if (frame - line_ptr < count * 2)
 280                     return AVERROR_INVALIDDATA;
 281                 v = bytestream2_get_le16(gb);
 282                 for (i = 0; i < count; i++)
 283                     bytestream_put_le16(&line_ptr, v);
 284             }
 285         }
 286     }
 287
 288     return 0;
 289 }
 290
 291 static int decode_tdlt(GetByteContext *gb, uint8_t *frame, int width, int height)
 292 {
 293     const uint8_t *frame_end = frame + width * height;
 294     int segments = bytestream2_get_le32(gb);
 295     int skip, copy;
 296
 297     while (segments--) {
 298         if (bytestream2_get_bytes_left(gb) < 2)
 299             return AVERROR_INVALIDDATA;
 300         copy = bytestream2_get_byteu(gb) * 2;
 301         skip = bytestream2_get_byteu(gb) * 2;
 302         if (frame_end - frame < copy + skip ||
 303             bytestream2_get_bytes_left(gb) < copy)
 304             return AVERROR_INVALIDDATA;
 305         frame += skip;
 306         bytestream2_get_buffer(gb, frame, copy);
 307         frame += copy;
 308     }
 309
 310     return 0;
 311 }
 312
 313 static int decode_blck(GetByteContext *gb, uint8_t *frame, int width, int height)
 314 {
 315     memset(frame, 0, width * height);
 316     return 0;
 317 }
 318
 319
 320 typedef int (*chunk_decoder)(GetByteContext *gb, uint8_t *frame, int width, int height);
 321
 322 static const chunk_decoder decoder[8] = {
 323     decode_copy, decode_tsw1, decode_bdlt, decode_wdlt,
 324     decode_tdlt, decode_dsw1, decode_blck, decode_dds1,
 325 };
 326
 327 static const char * const chunk_name[8] = {
 328     "COPY", "TSW1", "BDLT", "WDLT", "TDLT", "DSW1", "BLCK", "DDS1"
 329 };
 330
 331 static int dfa_decode_frame(AVCodecContext *avctx,
 332                             void *data, int *got_frame,
 333                             AVPacket *avpkt)
 334 {
 335     AVFrame *frame = data;
 336     DfaContext *s = avctx->priv_data;
 337     GetByteContext gb;
 338     const uint8_t *buf = avpkt->data;
 339     uint32_t chunk_type, chunk_size;
 340     uint8_t *dst;
 341     int ret;
 342     int i, pal_elems;
 343
 344     if ((ret = ff_get_buffer(avctx, frame, 0))) {
 345         av_log(avctx, AV_LOG_ERROR, "get_buffer() failed\n");
 346         return ret;
 347     }
 348
 349     bytestream2_init(&gb, avpkt->data, avpkt->size);
 350     while (bytestream2_get_bytes_left(&gb) > 0) {
 351         bytestream2_skip(&gb, 4);
 352         chunk_size = bytestream2_get_le32(&gb);
 353         chunk_type = bytestream2_get_le32(&gb);
 354         if (!chunk_type)
 355             break;
 356         if (chunk_type == 1) {
 357             pal_elems = FFMIN(chunk_size / 3, 256);
 358             for (i = 0; i < pal_elems; i++) {
 359                 s->pal[i] = bytestream2_get_be24(&gb) << 2;
 360                 s->pal[i] |= (s->pal[i] >> 6) & 0x333;
 361             }
 362             frame->palette_has_changed = 1;
 363         } else if (chunk_type <= 9) {
 364             if (decoder[chunk_type - 2](&gb, s->frame_buf, avctx->width, avctx->height)) {
 365                 av_log(avctx, AV_LOG_ERROR, "Error decoding %s chunk\n",
 366                        chunk_name[chunk_type - 2]);
 367                 return AVERROR_INVALIDDATA;
 368             }
 369         } else {
 370             av_log(avctx, AV_LOG_WARNING,
 371                    "Ignoring unknown chunk type %"PRIu32"\n",
 372                    chunk_type);
 373         }
 374         buf += chunk_size;
 375     }
 376
 377     buf = s->frame_buf;
 378     dst = frame->data[0];
 379     for (i = 0; i < avctx->height; i++) {
 380         memcpy(dst, buf, avctx->width);
 381         dst += frame->linesize[0];
 382         buf += avctx->width;
 383     }
 384     memcpy(frame->data[1], s->pal, sizeof(s->pal));
 385
 386     *got_frame = 1;
 387
 388     return avpkt->size;
 389 }
 390
 391 static av_cold int dfa_decode_end(AVCodecContext *avctx)
 392 {
 393     DfaContext *s = avctx->priv_data;
 394
 395     av_freep(&s->frame_buf);
 396
 397     return 0;
 398 }
 399
 400 AVCodec ff_dfa_decoder = {
 401     .name           = "dfa",
 402     .long_name      = NULL_IF_CONFIG_SMALL("Chronomaster DFA"),
 403     .type           = AVMEDIA_TYPE_VIDEO,
 404     .id             = AV_CODEC_ID_DFA,
 405     .priv_data_size = sizeof(DfaContext),
 406     .init           = dfa_decode_init,
 407     .close          = dfa_decode_end,
 408     .decode         = dfa_decode_frame,
 409     .capabilities   = AV_CODEC_CAP_DR1,
 410 };