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 "avcodec.h"
  24 #include "bytestream.h"
  25 #include "internal.h"
  26
  27 #include "libavutil/imgutils.h"
  28 #include "libavutil/mem.h"
  29
  30 typedef struct DfaContext {
  31     uint32_t pal[256];
  32     uint8_t *frame_buf;
  33 } DfaContext;
  34
  35 static av_cold int dfa_decode_init(AVCodecContext *avctx)
  36 {
  37     DfaContext *s = avctx->priv_data;
  38     int ret;
  39
  40     avctx->pix_fmt = AV_PIX_FMT_PAL8;
  41
  42     if ((ret = av_image_check_size(avctx->width, avctx->height, 0, avctx)) < 0)
  43         return ret;
  44
  45     s->frame_buf = av_mallocz(avctx->width * avctx->height);
  46     if (!s->frame_buf)
  47         return AVERROR(ENOMEM);
  48
  49     return 0;
  50 }
  51
  52 static int decode_copy(GetByteContext *gb, uint8_t *frame, int width, int height)
  53 {
  54     const int size = width * height;
  55
  56     if (bytestream2_get_buffer(gb, frame, size) != size)
  57         return AVERROR_INVALIDDATA;
  58     return 0;
  59 }
  60
  61 static int decode_tsw1(GetByteContext *gb, uint8_t *frame, int width, int height)
  62 {
  63     const uint8_t *frame_start = frame;
  64     const uint8_t *frame_end   = frame + width * height;
  65     int mask = 0x10000, bitbuf = 0;
  66     int v, count, segments;
  67     unsigned offset;
  68
  69     segments = bytestream2_get_le32(gb);
  70     offset   = bytestream2_get_le32(gb);
  71     if (frame_end - frame <= offset)
  72         return AVERROR_INVALIDDATA;
  73     frame += offset;
  74     while (segments--) {
  75         if (bytestream2_get_bytes_left(gb) < 2)
  76             return AVERROR_INVALIDDATA;
  77         if (mask == 0x10000) {
  78             bitbuf = bytestream2_get_le16u(gb);
  79             mask = 1;
  80         }
  81         if (frame_end - frame < 2)
  82             return AVERROR_INVALIDDATA;
  83         if (bitbuf & mask) {
  84             v = bytestream2_get_le16(gb);
  85             offset = (v & 0x1FFF) << 1;
  86             count = ((v >> 13) + 2) << 1;
  87             if (frame - frame_start < offset || frame_end - frame < count)
  88                 return AVERROR_INVALIDDATA;
  89             av_memcpy_backptr(frame, offset, count);
  90             frame += count;
  91         } else {
  92             *frame++ = bytestream2_get_byte(gb);
  93             *frame++ = bytestream2_get_byte(gb);
  94         }
  95         mask <<= 1;
  96     }
  97
  98     return 0;
  99 }
 100
 101 static int decode_dsw1(GetByteContext *gb, uint8_t *frame, int width, int height)
 102 {
 103     const uint8_t *frame_start = frame;
 104     const uint8_t *frame_end   = frame + width * height;
 105     int mask = 0x10000, bitbuf = 0;
 106     int v, offset, count, segments;
 107
 108     segments = bytestream2_get_le16(gb);
 109     while (segments--) {
 110         if (bytestream2_get_bytes_left(gb) < 2)
 111             return AVERROR_INVALIDDATA;
 112         if (mask == 0x10000) {
 113             bitbuf = bytestream2_get_le16u(gb);
 114             mask = 1;
 115         }
 116         if (frame_end - frame < 2)
 117             return AVERROR_INVALIDDATA;
 118         if (bitbuf & mask) {
 119             v = bytestream2_get_le16(gb);
 120             offset = (v & 0x1FFF) << 1;
 121             count = ((v >> 13) + 2) << 1;
 122             if (frame - frame_start < offset || frame_end - frame < count)
 123                 return AVERROR_INVALIDDATA;
 124             av_memcpy_backptr(frame, offset, count);
 125             frame += count;
 126         } else if (bitbuf & (mask << 1)) {
 127             frame += bytestream2_get_le16(gb);
 128         } else {
 129             *frame++ = bytestream2_get_byte(gb);
 130             *frame++ = bytestream2_get_byte(gb);
 131         }
 132         mask <<= 2;
 133     }
 134
 135     return 0;
 136 }
 137
 138 static int decode_dds1(GetByteContext *gb, uint8_t *frame, int width, int height)
 139 {
 140     const uint8_t *frame_start = frame;
 141     const uint8_t *frame_end   = frame + width * height;
 142     int mask = 0x10000, bitbuf = 0;
 143     int i, v, offset, count, segments;
 144
 145     segments = bytestream2_get_le16(gb);
 146     while (segments--) {
 147         if (bytestream2_get_bytes_left(gb) < 2)
 148             return AVERROR_INVALIDDATA;
 149         if (mask == 0x10000) {
 150             bitbuf = bytestream2_get_le16u(gb);
 151             mask = 1;
 152         }
 153
 154         if (bitbuf & mask) {
 155             v = bytestream2_get_le16(gb);
 156             offset = (v & 0x1FFF) << 2;
 157             count = ((v >> 13) + 2) << 1;
 158             if (frame - frame_start < offset || frame_end - frame < count*2 + width)
 159                 return AVERROR_INVALIDDATA;
 160             for (i = 0; i < count; i++) {
 161                 frame[0] = frame[1] =
 162                 frame[width] = frame[width + 1] = frame[-offset];
 163
 164                 frame += 2;
 165             }
 166         } else if (bitbuf & (mask << 1)) {
 167             v = bytestream2_get_le16(gb)*2;
 168             if (frame - frame_end < v)
 169                 return AVERROR_INVALIDDATA;
 170             frame += v;
 171         } else {
 172             if (frame_end - frame < width + 3)
 173                 return AVERROR_INVALIDDATA;
 174             frame[0] = frame[1] =
 175             frame[width] = frame[width + 1] =  bytestream2_get_byte(gb);
 176             frame += 2;
 177             frame[0] = frame[1] =
 178             frame[width] = frame[width + 1] =  bytestream2_get_byte(gb);
 179             frame += 2;
 180         }
 181         mask <<= 2;
 182     }
 183
 184     return 0;
 185 }
 186
 187 static int decode_bdlt(GetByteContext *gb, uint8_t *frame, int width, int height)
 188 {
 189     uint8_t *line_ptr;
 190     int count, lines, segments;
 191
 192     count = bytestream2_get_le16(gb);
 193     if (count >= height)
 194         return AVERROR_INVALIDDATA;
 195     frame += width * count;
 196     lines = bytestream2_get_le16(gb);
 197     if (count + lines > height)
 198         return AVERROR_INVALIDDATA;
 199
 200     while (lines--) {
 201         if (bytestream2_get_bytes_left(gb) < 1)
 202             return AVERROR_INVALIDDATA;
 203         line_ptr = frame;
 204         frame += width;
 205         segments = bytestream2_get_byteu(gb);
 206         while (segments--) {
 207             if (frame - line_ptr <= bytestream2_peek_byte(gb))
 208                 return AVERROR_INVALIDDATA;
 209             line_ptr += bytestream2_get_byte(gb);
 210             count = (int8_t)bytestream2_get_byte(gb);
 211             if (count >= 0) {
 212                 if (frame - line_ptr < count)
 213                     return AVERROR_INVALIDDATA;
 214                 if (bytestream2_get_buffer(gb, line_ptr, count) != count)
 215                     return AVERROR_INVALIDDATA;
 216             } else {
 217                 count = -count;
 218                 if (frame - line_ptr < count)
 219                     return AVERROR_INVALIDDATA;
 220                 memset(line_ptr, bytestream2_get_byte(gb), count);
 221             }
 222             line_ptr += count;
 223         }
 224     }
 225
 226     return 0;
 227 }
 228
 229 static int decode_wdlt(GetByteContext *gb, uint8_t *frame, int width, int height)
 230 {
 231     const uint8_t *frame_end   = frame + width * height;
 232     uint8_t *line_ptr;
 233     int count, i, v, lines, segments;
 234     int y = 0;
 235
 236     lines = bytestream2_get_le16(gb);
 237     if (lines > height)
 238         return AVERROR_INVALIDDATA;
 239
 240     while (lines--) {
 241         if (bytestream2_get_bytes_left(gb) < 2)
 242             return AVERROR_INVALIDDATA;
 243         segments = bytestream2_get_le16u(gb);
 244         while ((segments & 0xC000) == 0xC000) {
 245             unsigned skip_lines = -(int16_t)segments;
 246             unsigned delta = -((int16_t)segments * width);
 247             if (frame_end - frame <= delta || y + lines + skip_lines > height)
 248                 return AVERROR_INVALIDDATA;
 249             frame    += delta;
 250             y        += skip_lines;
 251             segments = bytestream2_get_le16(gb);
 252         }
 253         if (segments & 0x8000) {
 254             frame[width - 1] = segments & 0xFF;
 255             segments = bytestream2_get_le16(gb);
 256         }
 257         line_ptr = frame;
 258         frame += width;
 259         y++;
 260         while (segments--) {
 261             if (frame - line_ptr <= bytestream2_peek_byte(gb))
 262                 return AVERROR_INVALIDDATA;
 263             line_ptr += bytestream2_get_byte(gb);
 264             count = (int8_t)bytestream2_get_byte(gb);
 265             if (count >= 0) {
 266                 if (frame - line_ptr < count * 2)
 267                     return AVERROR_INVALIDDATA;
 268                 if (bytestream2_get_buffer(gb, line_ptr, count * 2) != count * 2)
 269                     return AVERROR_INVALIDDATA;
 270                 line_ptr += count * 2;
 271             } else {
 272                 count = -count;
 273                 if (frame - line_ptr < count * 2)
 274                     return AVERROR_INVALIDDATA;
 275                 v = bytestream2_get_le16(gb);
 276                 for (i = 0; i < count; i++)
 277                     bytestream_put_le16(&line_ptr, v);
 278             }
 279         }
 280     }
 281
 282     return 0;
 283 }
 284
 285 static int decode_unk6(GetByteContext *gb, uint8_t *frame, int width, int height)
 286 {
 287     return AVERROR_PATCHWELCOME;
 288 }
 289
 290 static int decode_blck(GetByteContext *gb, uint8_t *frame, int width, int height)
 291 {
 292     memset(frame, 0, width * height);
 293     return 0;
 294 }
 295
 296
 297 typedef int (*chunk_decoder)(GetByteContext *gb, uint8_t *frame, int width, int height);
 298
 299 static const chunk_decoder decoder[8] = {
 300     decode_copy, decode_tsw1, decode_bdlt, decode_wdlt,
 301     decode_unk6, decode_dsw1, decode_blck, decode_dds1,
 302 };
 303
 304 static const char* chunk_name[8] = {
 305     "COPY", "TSW1", "BDLT", "WDLT", "????", "DSW1", "BLCK", "DDS1"
 306 };
 307
 308 static int dfa_decode_frame(AVCodecContext *avctx,
 309                             void *data, int *got_frame,
 310                             AVPacket *avpkt)
 311 {
 312     AVFrame *frame = data;
 313     DfaContext *s = avctx->priv_data;
 314     GetByteContext gb;
 315     const uint8_t *buf = avpkt->data;
 316     uint32_t chunk_type, chunk_size;
 317     uint8_t *dst;
 318     int ret;
 319     int i, pal_elems;
 320
 321     if ((ret = ff_get_buffer(avctx, frame, 0))) {
 322         av_log(avctx, AV_LOG_ERROR, "get_buffer() failed\n");
 323         return ret;
 324     }
 325
 326     bytestream2_init(&gb, avpkt->data, avpkt->size);
 327     while (bytestream2_get_bytes_left(&gb) > 0) {
 328         bytestream2_skip(&gb, 4);
 329         chunk_size = bytestream2_get_le32(&gb);
 330         chunk_type = bytestream2_get_le32(&gb);
 331         if (!chunk_type)
 332             break;
 333         if (chunk_type == 1) {
 334             pal_elems = FFMIN(chunk_size / 3, 256);
 335             for (i = 0; i < pal_elems; i++) {
 336                 s->pal[i] = bytestream2_get_be24(&gb) << 2;
 337                 s->pal[i] |= (s->pal[i] >> 6) & 0x333;
 338             }
 339             frame->palette_has_changed = 1;
 340         } else if (chunk_type <= 9) {
 341             if (decoder[chunk_type - 2](&gb, s->frame_buf, avctx->width, avctx->height)) {
 342                 av_log(avctx, AV_LOG_ERROR, "Error decoding %s chunk\n",
 343                        chunk_name[chunk_type - 2]);
 344                 return AVERROR_INVALIDDATA;
 345             }
 346         } else {
 347             av_log(avctx, AV_LOG_WARNING, "Ignoring unknown chunk type %d\n",
 348                    chunk_type);
 349         }
 350         buf += chunk_size;
 351     }
 352
 353     buf = s->frame_buf;
 354     dst = frame->data[0];
 355     for (i = 0; i < avctx->height; i++) {
 356         memcpy(dst, buf, avctx->width);
 357         dst += frame->linesize[0];
 358         buf += avctx->width;
 359     }
 360     memcpy(frame->data[1], s->pal, sizeof(s->pal));
 361
 362     *got_frame = 1;
 363
 364     return avpkt->size;
 365 }
 366
 367 static av_cold int dfa_decode_end(AVCodecContext *avctx)
 368 {
 369     DfaContext *s = avctx->priv_data;
 370
 371     av_freep(&s->frame_buf);
 372
 373     return 0;
 374 }
 375
 376 AVCodec ff_dfa_decoder = {
 377     .name           = "dfa",
 378     .type           = AVMEDIA_TYPE_VIDEO,
 379     .id             = AV_CODEC_ID_DFA,
 380     .priv_data_size = sizeof(DfaContext),
 381     .init           = dfa_decode_init,
 382     .close          = dfa_decode_end,
 383     .decode         = dfa_decode_frame,
 384     .capabilities   = CODEC_CAP_DR1,
 385     .long_name      = NULL_IF_CONFIG_SMALL("Chronomaster DFA"),
 386 };