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
  26 #include "libavutil/imgutils.h"
  27 #include "libavutil/mem.h"
  28
  29 typedef struct DfaContext {
  30     AVFrame pic;
  31
  32     uint32_t pal[256];
  33     uint8_t *frame_buf;
  34 } DfaContext;
  35
  36 static av_cold int dfa_decode_init(AVCodecContext *avctx)
  37 {
  38     DfaContext *s = avctx->priv_data;
  39     int ret;
  40
  41     avctx->pix_fmt = AV_PIX_FMT_PAL8;
  42
  43     if ((ret = av_image_check_size(avctx->width, avctx->height, 0, avctx)) < 0)
  44         return ret;
  45
  46     s->frame_buf = av_mallocz(avctx->width * avctx->height);
  47     if (!s->frame_buf)
  48         return AVERROR(ENOMEM);
  49
  50     return 0;
  51 }
  52
  53 static int decode_copy(GetByteContext *gb, uint8_t *frame, int width, int height)
  54 {
  55     const int size = width * height;
  56
  57     if (bytestream2_get_buffer(gb, frame, size) != size)
  58         return AVERROR_INVALIDDATA;
  59     return 0;
  60 }
  61
  62 static int decode_tsw1(GetByteContext *gb, uint8_t *frame, int width, int height)
  63 {
  64     const uint8_t *frame_start = frame;
  65     const uint8_t *frame_end   = frame + width * height;
  66     int mask = 0x10000, bitbuf = 0;
  67     int v, count, segments;
  68     unsigned offset;
  69
  70     segments = bytestream2_get_le32(gb);
  71     offset   = bytestream2_get_le32(gb);
  72     if (frame_end - frame <= offset)
  73         return AVERROR_INVALIDDATA;
  74     frame += offset;
  75     while (segments--) {
  76         if (bytestream2_get_bytes_left(gb) < 2)
  77             return AVERROR_INVALIDDATA;
  78         if (mask == 0x10000) {
  79             bitbuf = bytestream2_get_le16u(gb);
  80             mask = 1;
  81         }
  82         if (frame_end - frame < 2)
  83             return AVERROR_INVALIDDATA;
  84         if (bitbuf & mask) {
  85             v = bytestream2_get_le16(gb);
  86             offset = (v & 0x1FFF) << 1;
  87             count = ((v >> 13) + 2) << 1;
  88             if (frame - frame_start < offset || frame_end - frame < count)
  89                 return AVERROR_INVALIDDATA;
  90             av_memcpy_backptr(frame, offset, count);
  91             frame += count;
  92         } else {
  93             *frame++ = bytestream2_get_byte(gb);
  94             *frame++ = bytestream2_get_byte(gb);
  95         }
  96         mask <<= 1;
  97     }
  98
  99     return 0;
 100 }
 101
 102 static int decode_dsw1(GetByteContext *gb, uint8_t *frame, int width, int height)
 103 {
 104     const uint8_t *frame_start = frame;
 105     const uint8_t *frame_end   = frame + width * height;
 106     int mask = 0x10000, bitbuf = 0;
 107     int v, offset, count, segments;
 108
 109     segments = bytestream2_get_le16(gb);
 110     while (segments--) {
 111         if (bytestream2_get_bytes_left(gb) < 2)
 112             return AVERROR_INVALIDDATA;
 113         if (mask == 0x10000) {
 114             bitbuf = bytestream2_get_le16u(gb);
 115             mask = 1;
 116         }
 117         if (frame_end - frame < 2)
 118             return AVERROR_INVALIDDATA;
 119         if (bitbuf & mask) {
 120             v = bytestream2_get_le16(gb);
 121             offset = (v & 0x1FFF) << 1;
 122             count = ((v >> 13) + 2) << 1;
 123             if (frame - frame_start < offset || frame_end - frame < count)
 124                 return AVERROR_INVALIDDATA;
 125             av_memcpy_backptr(frame, offset, count);
 126             frame += count;
 127         } else if (bitbuf & (mask << 1)) {
 128             frame += bytestream2_get_le16(gb);
 129         } else {
 130             *frame++ = bytestream2_get_byte(gb);
 131             *frame++ = bytestream2_get_byte(gb);
 132         }
 133         mask <<= 2;
 134     }
 135
 136     return 0;
 137 }
 138
 139 static int decode_dds1(GetByteContext *gb, uint8_t *frame, int width, int height)
 140 {
 141     const uint8_t *frame_start = frame;
 142     const uint8_t *frame_end   = frame + width * height;
 143     int mask = 0x10000, bitbuf = 0;
 144     int i, v, offset, count, segments;
 145
 146     segments = bytestream2_get_le16(gb);
 147     while (segments--) {
 148         if (bytestream2_get_bytes_left(gb) < 2)
 149             return AVERROR_INVALIDDATA;
 150         if (mask == 0x10000) {
 151             bitbuf = bytestream2_get_le16u(gb);
 152             mask = 1;
 153         }
 154
 155         if (bitbuf & mask) {
 156             v = bytestream2_get_le16(gb);
 157             offset = (v & 0x1FFF) << 2;
 158             count = ((v >> 13) + 2) << 1;
 159             if (frame - frame_start < offset || frame_end - frame < count*2 + width)
 160                 return AVERROR_INVALIDDATA;
 161             for (i = 0; i < count; i++) {
 162                 frame[0] = frame[1] =
 163                 frame[width] = frame[width + 1] = frame[-offset];
 164
 165                 frame += 2;
 166             }
 167         } else if (bitbuf & (mask << 1)) {
 168             v = bytestream2_get_le16(gb)*2;
 169             if (frame - frame_end < v)
 170                 return AVERROR_INVALIDDATA;
 171             frame += v;
 172         } else {
 173             if (frame_end - frame < width + 3)
 174                 return AVERROR_INVALIDDATA;
 175             frame[0] = frame[1] =
 176             frame[width] = frame[width + 1] =  bytestream2_get_byte(gb);
 177             frame += 2;
 178             frame[0] = frame[1] =
 179             frame[width] = frame[width + 1] =  bytestream2_get_byte(gb);
 180             frame += 2;
 181         }
 182         mask <<= 2;
 183     }
 184
 185     return 0;
 186 }
 187
 188 static int decode_bdlt(GetByteContext *gb, uint8_t *frame, int width, int height)
 189 {
 190     uint8_t *line_ptr;
 191     int count, lines, segments;
 192
 193     count = bytestream2_get_le16(gb);
 194     if (count >= height)
 195         return AVERROR_INVALIDDATA;
 196     frame += width * count;
 197     lines = bytestream2_get_le16(gb);
 198     if (count + lines > height)
 199         return AVERROR_INVALIDDATA;
 200
 201     while (lines--) {
 202         if (bytestream2_get_bytes_left(gb) < 1)
 203             return AVERROR_INVALIDDATA;
 204         line_ptr = frame;
 205         frame += width;
 206         segments = bytestream2_get_byteu(gb);
 207         while (segments--) {
 208             if (frame - line_ptr <= bytestream2_peek_byte(gb))
 209                 return AVERROR_INVALIDDATA;
 210             line_ptr += bytestream2_get_byte(gb);
 211             count = (int8_t)bytestream2_get_byte(gb);
 212             if (count >= 0) {
 213                 if (frame - line_ptr < count)
 214                     return AVERROR_INVALIDDATA;
 215                 if (bytestream2_get_buffer(gb, line_ptr, count) != count)
 216                     return AVERROR_INVALIDDATA;
 217             } else {
 218                 count = -count;
 219                 if (frame - line_ptr < count)
 220                     return AVERROR_INVALIDDATA;
 221                 memset(line_ptr, bytestream2_get_byte(gb), count);
 222             }
 223             line_ptr += count;
 224         }
 225     }
 226
 227     return 0;
 228 }
 229
 230 static int decode_wdlt(GetByteContext *gb, uint8_t *frame, int width, int height)
 231 {
 232     const uint8_t *frame_end   = frame + width * height;
 233     uint8_t *line_ptr;
 234     int count, i, v, lines, segments;
 235     int y = 0;
 236
 237     lines = bytestream2_get_le16(gb);
 238     if (lines > height)
 239         return AVERROR_INVALIDDATA;
 240
 241     while (lines--) {
 242         if (bytestream2_get_bytes_left(gb) < 2)
 243             return AVERROR_INVALIDDATA;
 244         segments = bytestream2_get_le16u(gb);
 245         while ((segments & 0xC000) == 0xC000) {
 246             unsigned skip_lines = -(int16_t)segments;
 247             unsigned delta = -((int16_t)segments * width);
 248             if (frame_end - frame <= delta || y + lines + skip_lines > height)
 249                 return AVERROR_INVALIDDATA;
 250             frame    += delta;
 251             y        += skip_lines;
 252             segments = bytestream2_get_le16(gb);
 253         }
 254         if (segments & 0x8000) {
 255             frame[width - 1] = segments & 0xFF;
 256             segments = bytestream2_get_le16(gb);
 257         }
 258         line_ptr = frame;
 259         frame += width;
 260         y++;
 261         while (segments--) {
 262             if (frame - line_ptr <= bytestream2_peek_byte(gb))
 263                 return AVERROR_INVALIDDATA;
 264             line_ptr += bytestream2_get_byte(gb);
 265             count = (int8_t)bytestream2_get_byte(gb);
 266             if (count >= 0) {
 267                 if (frame - line_ptr < count * 2)
 268                     return AVERROR_INVALIDDATA;
 269                 if (bytestream2_get_buffer(gb, line_ptr, count * 2) != count * 2)
 270                     return AVERROR_INVALIDDATA;
 271                 line_ptr += count * 2;
 272             } else {
 273                 count = -count;
 274                 if (frame - line_ptr < count * 2)
 275                     return AVERROR_INVALIDDATA;
 276                 v = bytestream2_get_le16(gb);
 277                 for (i = 0; i < count; i++)
 278                     bytestream_put_le16(&line_ptr, v);
 279             }
 280         }
 281     }
 282
 283     return 0;
 284 }
 285
 286 static int decode_unk6(GetByteContext *gb, uint8_t *frame, int width, int height)
 287 {
 288     return AVERROR_PATCHWELCOME;
 289 }
 290
 291 static int decode_blck(GetByteContext *gb, uint8_t *frame, int width, int height)
 292 {
 293     memset(frame, 0, width * height);
 294     return 0;
 295 }
 296
 297
 298 typedef int (*chunk_decoder)(GetByteContext *gb, uint8_t *frame, int width, int height);
 299
 300 static const chunk_decoder decoder[8] = {
 301     decode_copy, decode_tsw1, decode_bdlt, decode_wdlt,
 302     decode_unk6, decode_dsw1, decode_blck, decode_dds1,
 303 };
 304
 305 static const char* chunk_name[8] = {
 306     "COPY", "TSW1", "BDLT", "WDLT", "????", "DSW1", "BLCK", "DDS1"
 307 };
 308
 309 static int dfa_decode_frame(AVCodecContext *avctx,
 310                             void *data, int *data_size,
 311                             AVPacket *avpkt)
 312 {
 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 (s->pic.data[0])
 322         avctx->release_buffer(avctx, &s->pic);
 323
 324     if ((ret = avctx->get_buffer(avctx, &s->pic))) {
 325         av_log(avctx, AV_LOG_ERROR, "get_buffer() failed\n");
 326         return ret;
 327     }
 328
 329     bytestream2_init(&gb, avpkt->data, avpkt->size);
 330     while (bytestream2_get_bytes_left(&gb) > 0) {
 331         bytestream2_skip(&gb, 4);
 332         chunk_size = bytestream2_get_le32(&gb);
 333         chunk_type = bytestream2_get_le32(&gb);
 334         if (!chunk_type)
 335             break;
 336         if (chunk_type == 1) {
 337             pal_elems = FFMIN(chunk_size / 3, 256);
 338             for (i = 0; i < pal_elems; i++) {
 339                 s->pal[i] = bytestream2_get_be24(&gb) << 2;
 340                 s->pal[i] |= (s->pal[i] >> 6) & 0x333;
 341             }
 342             s->pic.palette_has_changed = 1;
 343         } else if (chunk_type <= 9) {
 344             if (decoder[chunk_type - 2](&gb, s->frame_buf, avctx->width, avctx->height)) {
 345                 av_log(avctx, AV_LOG_ERROR, "Error decoding %s chunk\n",
 346                        chunk_name[chunk_type - 2]);
 347                 return AVERROR_INVALIDDATA;
 348             }
 349         } else {
 350             av_log(avctx, AV_LOG_WARNING, "Ignoring unknown chunk type %d\n",
 351                    chunk_type);
 352         }
 353         buf += chunk_size;
 354     }
 355
 356     buf = s->frame_buf;
 357     dst = s->pic.data[0];
 358     for (i = 0; i < avctx->height; i++) {
 359         memcpy(dst, buf, avctx->width);
 360         dst += s->pic.linesize[0];
 361         buf += avctx->width;
 362     }
 363     memcpy(s->pic.data[1], s->pal, sizeof(s->pal));
 364
 365     *data_size = sizeof(AVFrame);
 366     *(AVFrame*)data = s->pic;
 367
 368     return avpkt->size;
 369 }
 370
 371 static av_cold int dfa_decode_end(AVCodecContext *avctx)
 372 {
 373     DfaContext *s = avctx->priv_data;
 374
 375     if (s->pic.data[0])
 376         avctx->release_buffer(avctx, &s->pic);
 377
 378     av_freep(&s->frame_buf);
 379
 380     return 0;
 381 }
 382
 383 AVCodec ff_dfa_decoder = {
 384     .name           = "dfa",
 385     .type           = AVMEDIA_TYPE_VIDEO,
 386     .id             = AV_CODEC_ID_DFA,
 387     .priv_data_size = sizeof(DfaContext),
 388     .init           = dfa_decode_init,
 389     .close          = dfa_decode_end,
 390     .decode         = dfa_decode_frame,
 391     .capabilities   = CODEC_CAP_DR1,
 392     .long_name      = NULL_IF_CONFIG_SMALL("Chronomaster DFA"),
 393 };