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     AVFrame pic;
  32
  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     segments = bytestream2_get_le16(gb);
 148     while (segments--) {
 149         if (bytestream2_get_bytes_left(gb) < 2)
 150             return AVERROR_INVALIDDATA;
 151         if (mask == 0x10000) {
 152             bitbuf = bytestream2_get_le16u(gb);
 153             mask = 1;
 154         }
 155
 156         if (bitbuf & mask) {
 157             v = bytestream2_get_le16(gb);
 158             offset = (v & 0x1FFF) << 2;
 159             count = ((v >> 13) + 2) << 1;
 160             if (frame - frame_start < offset || frame_end - frame < count*2 + width)
 161                 return AVERROR_INVALIDDATA;
 162             for (i = 0; i < count; i++) {
 163                 frame[0] = frame[1] =
 164                 frame[width] = frame[width + 1] = frame[-offset];
 165
 166                 frame += 2;
 167             }
 168         } else if (bitbuf & (mask << 1)) {
 169             v = bytestream2_get_le16(gb)*2;
 170             if (frame - frame_end < v)
 171                 return AVERROR_INVALIDDATA;
 172             frame += v;
 173         } else {
 174             if (frame_end - frame < width + 3)
 175                 return AVERROR_INVALIDDATA;
 176             frame[0] = frame[1] =
 177             frame[width] = frame[width + 1] =  bytestream2_get_byte(gb);
 178             frame += 2;
 179             frame[0] = frame[1] =
 180             frame[width] = frame[width + 1] =  bytestream2_get_byte(gb);
 181             frame += 2;
 182         }
 183         mask <<= 2;
 184     }
 185
 186     return 0;
 187 }
 188
 189 static int decode_bdlt(GetByteContext *gb, uint8_t *frame, int width, int height)
 190 {
 191     uint8_t *line_ptr;
 192     int count, lines, segments;
 193
 194     count = bytestream2_get_le16(gb);
 195     if (count >= height)
 196         return AVERROR_INVALIDDATA;
 197     frame += width * count;
 198     lines = bytestream2_get_le16(gb);
 199     if (count + lines > height)
 200         return AVERROR_INVALIDDATA;
 201
 202     while (lines--) {
 203         if (bytestream2_get_bytes_left(gb) < 1)
 204             return AVERROR_INVALIDDATA;
 205         line_ptr = frame;
 206         frame += width;
 207         segments = bytestream2_get_byteu(gb);
 208         while (segments--) {
 209             if (frame - line_ptr <= bytestream2_peek_byte(gb))
 210                 return AVERROR_INVALIDDATA;
 211             line_ptr += bytestream2_get_byte(gb);
 212             count = (int8_t)bytestream2_get_byte(gb);
 213             if (count >= 0) {
 214                 if (frame - line_ptr < count)
 215                     return AVERROR_INVALIDDATA;
 216                 if (bytestream2_get_buffer(gb, line_ptr, count) != count)
 217                     return AVERROR_INVALIDDATA;
 218             } else {
 219                 count = -count;
 220                 if (frame - line_ptr < count)
 221                     return AVERROR_INVALIDDATA;
 222                 memset(line_ptr, bytestream2_get_byte(gb), count);
 223             }
 224             line_ptr += count;
 225         }
 226     }
 227
 228     return 0;
 229 }
 230
 231 static int decode_wdlt(GetByteContext *gb, uint8_t *frame, int width, int height)
 232 {
 233     const uint8_t *frame_end   = frame + width * height;
 234     uint8_t *line_ptr;
 235     int count, i, v, lines, segments;
 236     int y = 0;
 237
 238     lines = bytestream2_get_le16(gb);
 239     if (lines > height)
 240         return AVERROR_INVALIDDATA;
 241
 242     while (lines--) {
 243         if (bytestream2_get_bytes_left(gb) < 2)
 244             return AVERROR_INVALIDDATA;
 245         segments = bytestream2_get_le16u(gb);
 246         while ((segments & 0xC000) == 0xC000) {
 247             unsigned skip_lines = -(int16_t)segments;
 248             unsigned delta = -((int16_t)segments * width);
 249             if (frame_end - frame <= delta || y + lines + skip_lines > height)
 250                 return AVERROR_INVALIDDATA;
 251             frame    += delta;
 252             y        += skip_lines;
 253             segments = bytestream2_get_le16(gb);
 254         }
 255         if (segments & 0x8000) {
 256             frame[width - 1] = segments & 0xFF;
 257             segments = bytestream2_get_le16(gb);
 258         }
 259         line_ptr = frame;
 260         frame += width;
 261         y++;
 262         while (segments--) {
 263             if (frame - line_ptr <= bytestream2_peek_byte(gb))
 264                 return AVERROR_INVALIDDATA;
 265             line_ptr += bytestream2_get_byte(gb);
 266             count = (int8_t)bytestream2_get_byte(gb);
 267             if (count >= 0) {
 268                 if (frame - line_ptr < count * 2)
 269                     return AVERROR_INVALIDDATA;
 270                 if (bytestream2_get_buffer(gb, line_ptr, count * 2) != count * 2)
 271                     return AVERROR_INVALIDDATA;
 272                 line_ptr += count * 2;
 273             } else {
 274                 count = -count;
 275                 if (frame - line_ptr < count * 2)
 276                     return AVERROR_INVALIDDATA;
 277                 v = bytestream2_get_le16(gb);
 278                 for (i = 0; i < count; i++)
 279                     bytestream_put_le16(&line_ptr, v);
 280             }
 281         }
 282     }
 283
 284     return 0;
 285 }
 286
 287 static int decode_unk6(GetByteContext *gb, uint8_t *frame, int width, int height)
 288 {
 289     return AVERROR_PATCHWELCOME;
 290 }
 291
 292 static int decode_blck(GetByteContext *gb, uint8_t *frame, int width, int height)
 293 {
 294     memset(frame, 0, width * height);
 295     return 0;
 296 }
 297
 298
 299 typedef int (*chunk_decoder)(GetByteContext *gb, uint8_t *frame, int width, int height);
 300
 301 static const chunk_decoder decoder[8] = {
 302     decode_copy, decode_tsw1, decode_bdlt, decode_wdlt,
 303     decode_unk6, decode_dsw1, decode_blck, decode_dds1,
 304 };
 305
 306 static const char* chunk_name[8] = {
 307     "COPY", "TSW1", "BDLT", "WDLT", "????", "DSW1", "BLCK", "DDS1"
 308 };
 309
 310 static int dfa_decode_frame(AVCodecContext *avctx,
 311                             void *data, int *got_frame,
 312                             AVPacket *avpkt)
 313 {
 314     DfaContext *s = avctx->priv_data;
 315     GetByteContext gb;
 316     const uint8_t *buf = avpkt->data;
 317     uint32_t chunk_type, chunk_size;
 318     uint8_t *dst;
 319     int ret;
 320     int i, pal_elems;
 321
 322     if (s->pic.data[0])
 323         avctx->release_buffer(avctx, &s->pic);
 324
 325     if ((ret = ff_get_buffer(avctx, &s->pic))) {
 326         av_log(avctx, AV_LOG_ERROR, "get_buffer() failed\n");
 327         return ret;
 328     }
 329
 330     bytestream2_init(&gb, avpkt->data, avpkt->size);
 331     while (bytestream2_get_bytes_left(&gb) > 0) {
 332         bytestream2_skip(&gb, 4);
 333         chunk_size = bytestream2_get_le32(&gb);
 334         chunk_type = bytestream2_get_le32(&gb);
 335         if (!chunk_type)
 336             break;
 337         if (chunk_type == 1) {
 338             pal_elems = FFMIN(chunk_size / 3, 256);
 339             for (i = 0; i < pal_elems; i++) {
 340                 s->pal[i] = bytestream2_get_be24(&gb) << 2;
 341                 s->pal[i] |= (s->pal[i] >> 6) & 0x333;
 342             }
 343             s->pic.palette_has_changed = 1;
 344         } else if (chunk_type <= 9) {
 345             if (decoder[chunk_type - 2](&gb, s->frame_buf, avctx->width, avctx->height)) {
 346                 av_log(avctx, AV_LOG_ERROR, "Error decoding %s chunk\n",
 347                        chunk_name[chunk_type - 2]);
 348                 return AVERROR_INVALIDDATA;
 349             }
 350         } else {
 351             av_log(avctx, AV_LOG_WARNING, "Ignoring unknown chunk type %d\n",
 352                    chunk_type);
 353         }
 354         buf += chunk_size;
 355     }
 356
 357     buf = s->frame_buf;
 358     dst = s->pic.data[0];
 359     for (i = 0; i < avctx->height; i++) {
 360         memcpy(dst, buf, avctx->width);
 361         dst += s->pic.linesize[0];
 362         buf += avctx->width;
 363     }
 364     memcpy(s->pic.data[1], s->pal, sizeof(s->pal));
 365
 366     *got_frame = 1;
 367     *(AVFrame*)data = s->pic;
 368
 369     return avpkt->size;
 370 }
 371
 372 static av_cold int dfa_decode_end(AVCodecContext *avctx)
 373 {
 374     DfaContext *s = avctx->priv_data;
 375
 376     if (s->pic.data[0])
 377         avctx->release_buffer(avctx, &s->pic);
 378
 379     av_freep(&s->frame_buf);
 380
 381     return 0;
 382 }
 383
 384 AVCodec ff_dfa_decoder = {
 385     .name           = "dfa",
 386     .type           = AVMEDIA_TYPE_VIDEO,
 387     .id             = AV_CODEC_ID_DFA,
 388     .priv_data_size = sizeof(DfaContext),
 389     .init           = dfa_decode_init,
 390     .close          = dfa_decode_end,
 391     .decode         = dfa_decode_frame,
 392     .capabilities   = CODEC_CAP_DR1,
 393     .long_name      = NULL_IF_CONFIG_SMALL("Chronomaster DFA"),
 394 };