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/lzo.h" // for av_memcpy_backptr 28 29typedef struct DfaContext { 30 AVFrame pic; 31 32 uint32_t pal[256]; 33 uint8_t *frame_buf; 34} DfaContext; 35 36static av_cold int dfa_decode_init(AVCodecContext *avctx) 37{ 38 DfaContext *s = avctx->priv_data; 39 int ret; 40 41 avctx->pix_fmt = 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 + AV_LZO_OUTPUT_PADDING); 47 if (!s->frame_buf) 48 return AVERROR(ENOMEM); 49 50 return 0; 51} 52 53static 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 62static 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 102static 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 // can't use av_memcpy_backptr() since it can overwrite following pixels 126 for (v = 0; v < count; v++) 127 frame[v] = frame[v - offset]; 128 frame += count; 129 } else if (bitbuf & (mask << 1)) { 130 frame += bytestream2_get_le16(gb); 131 } else { 132 *frame++ = bytestream2_get_byte(gb); 133 *frame++ = bytestream2_get_byte(gb); 134 } 135 mask <<= 2; 136 } 137 138 return 0; 139} 140 141static int decode_dds1(GetByteContext *gb, uint8_t *frame, int width, int height) 142{ 143 const uint8_t *frame_start = frame; 144 const uint8_t *frame_end = frame + width * height; 145 int mask = 0x10000, bitbuf = 0; 146 int i, v, offset, count, segments; 147 148 segments = bytestream2_get_le16(gb); 149 while (segments--) { 150 if (bytestream2_get_bytes_left(gb) < 2) 151 return AVERROR_INVALIDDATA; 152 if (mask == 0x10000) { 153 bitbuf = bytestream2_get_le16u(gb); 154 mask = 1; 155 } 156 157 if (bitbuf & mask) { 158 v = bytestream2_get_le16(gb); 159 offset = (v & 0x1FFF) << 2; 160 count = ((v >> 13) + 2) << 1; 161 if (frame - frame_start < offset || frame_end - frame < count*2 + width) 162 return AVERROR_INVALIDDATA; 163 for (i = 0; i < count; i++) { 164 frame[0] = frame[1] = 165 frame[width] = frame[width + 1] = frame[-offset]; 166 167 frame += 2; 168 } 169 } else if (bitbuf & (mask << 1)) { 170 v = bytestream2_get_le16(gb)*2; 171 if (frame - frame_end < v) 172 return AVERROR_INVALIDDATA; 173 frame += v; 174 } else { 175 if (frame_end - frame < width + 3) 176 return AVERROR_INVALIDDATA; 177 frame[0] = frame[1] = 178 frame[width] = frame[width + 1] = bytestream2_get_byte(gb); 179 frame += 2; 180 frame[0] = frame[1] = 181 frame[width] = frame[width + 1] = bytestream2_get_byte(gb); 182 frame += 2; 183 } 184 mask <<= 2; 185 } 186 187 return 0; 188} 189 190static int decode_bdlt(GetByteContext *gb, uint8_t *frame, int width, int height) 191{ 192 uint8_t *line_ptr; 193 int count, lines, segments; 194 195 count = bytestream2_get_le16(gb); 196 if (count >= height) 197 return AVERROR_INVALIDDATA; 198 frame += width * count; 199 lines = bytestream2_get_le16(gb); 200 if (count + lines > height) 201 return AVERROR_INVALIDDATA; 202 203 while (lines--) { 204 if (bytestream2_get_bytes_left(gb) < 1) 205 return AVERROR_INVALIDDATA; 206 line_ptr = frame; 207 frame += width; 208 segments = bytestream2_get_byteu(gb); 209 while (segments--) { 210 if (frame - line_ptr <= bytestream2_peek_byte(gb)) 211 return AVERROR_INVALIDDATA; 212 line_ptr += bytestream2_get_byte(gb); 213 count = (int8_t)bytestream2_get_byte(gb); 214 if (count >= 0) { 215 if (frame - line_ptr < count) 216 return AVERROR_INVALIDDATA; 217 if (bytestream2_get_buffer(gb, line_ptr, count) != count) 218 return AVERROR_INVALIDDATA; 219 } else { 220 count = -count; 221 if (frame - line_ptr < count) 222 return AVERROR_INVALIDDATA; 223 memset(line_ptr, bytestream2_get_byte(gb), count); 224 } 225 line_ptr += count; 226 } 227 } 228 229 return 0; 230} 231 232static int decode_wdlt(GetByteContext *gb, uint8_t *frame, int width, int height) 233{ 234 const uint8_t *frame_end = frame + width * height; 235 uint8_t *line_ptr; 236 int count, i, v, lines, segments; 237 int y = 0; 238 239 lines = bytestream2_get_le16(gb); 240 if (lines > height) 241 return AVERROR_INVALIDDATA; 242 243 while (lines--) { 244 if (bytestream2_get_bytes_left(gb) < 2) 245 return AVERROR_INVALIDDATA; 246 segments = bytestream2_get_le16u(gb); 247 while ((segments & 0xC000) == 0xC000) { 248 unsigned skip_lines = -(int16_t)segments; 249 unsigned delta = -((int16_t)segments * width); 250 if (frame_end - frame <= delta || y + lines + skip_lines > height) 251 return AVERROR_INVALIDDATA; 252 frame += delta; 253 y += skip_lines; 254 segments = bytestream2_get_le16(gb); 255 } 256 if (segments & 0x8000) { 257 frame[width - 1] = segments & 0xFF; 258 segments = bytestream2_get_le16(gb); 259 } 260 line_ptr = frame; 261 if (frame_end - frame < width) 262 return AVERROR_INVALIDDATA; 263 frame += width; 264 y++; 265 while (segments--) { 266 if (frame - line_ptr <= bytestream2_peek_byte(gb)) 267 return AVERROR_INVALIDDATA; 268 line_ptr += bytestream2_get_byte(gb); 269 count = (int8_t)bytestream2_get_byte(gb); 270 if (count >= 0) { 271 if (frame - line_ptr < count * 2) 272 return AVERROR_INVALIDDATA; 273 if (bytestream2_get_buffer(gb, line_ptr, count * 2) != count * 2) 274 return AVERROR_INVALIDDATA; 275 line_ptr += count * 2; 276 } else { 277 count = -count; 278 if (frame - line_ptr < count * 2) 279 return AVERROR_INVALIDDATA; 280 v = bytestream2_get_le16(gb); 281 for (i = 0; i < count; i++) 282 bytestream_put_le16(&line_ptr, v); 283 } 284 } 285 } 286 287 return 0; 288} 289 290static int decode_unk6(GetByteContext *gb, uint8_t *frame, int width, int height) 291{ 292 return AVERROR_PATCHWELCOME; 293} 294 295static int decode_blck(GetByteContext *gb, uint8_t *frame, int width, int height) 296{ 297 memset(frame, 0, width * height); 298 return 0; 299} 300 301 302typedef int (*chunk_decoder)(GetByteContext *gb, uint8_t *frame, int width, int height); 303 304static const chunk_decoder decoder[8] = { 305 decode_copy, decode_tsw1, decode_bdlt, decode_wdlt, 306 decode_unk6, decode_dsw1, decode_blck, decode_dds1, 307}; 308 309static const char* chunk_name[8] = { 310 "COPY", "TSW1", "BDLT", "WDLT", "????", "DSW1", "BLCK", "DDS1" 311}; 312 313static int dfa_decode_frame(AVCodecContext *avctx, 314 void *data, int *data_size, 315 AVPacket *avpkt) 316{ 317 DfaContext *s = avctx->priv_data; 318 GetByteContext gb; 319 const uint8_t *buf = avpkt->data; 320 uint32_t chunk_type, chunk_size; 321 uint8_t *dst; 322 int ret; 323 int i, pal_elems; 324 325 if (s->pic.data[0]) 326 avctx->release_buffer(avctx, &s->pic); 327 328 if ((ret = avctx->get_buffer(avctx, &s->pic))) { 329 av_log(avctx, AV_LOG_ERROR, "get_buffer() failed\n"); 330 return ret; 331 } 332 333 bytestream2_init(&gb, avpkt->data, avpkt->size); 334 while (bytestream2_get_bytes_left(&gb) > 0) { 335 bytestream2_skip(&gb, 4); 336 chunk_size = bytestream2_get_le32(&gb); 337 chunk_type = bytestream2_get_le32(&gb); 338 if (!chunk_type) 339 break; 340 if (chunk_type == 1) { 341 pal_elems = FFMIN(chunk_size / 3, 256); 342 for (i = 0; i < pal_elems; i++) { 343 s->pal[i] = bytestream2_get_be24(&gb) << 2; 344 s->pal[i] |= (s->pal[i] >> 6) & 0x333; 345 } 346 s->pic.palette_has_changed = 1; 347 } else if (chunk_type <= 9) { 348 if (decoder[chunk_type - 2](&gb, s->frame_buf, avctx->width, avctx->height)) { 349 av_log(avctx, AV_LOG_ERROR, "Error decoding %s chunk\n", 350 chunk_name[chunk_type - 2]); 351 return AVERROR_INVALIDDATA; 352 } 353 } else { 354 av_log(avctx, AV_LOG_WARNING, "Ignoring unknown chunk type %d\n", 355 chunk_type); 356 } 357 buf += chunk_size; 358 } 359 360 buf = s->frame_buf; 361 dst = s->pic.data[0]; 362 for (i = 0; i < avctx->height; i++) { 363 memcpy(dst, buf, avctx->width); 364 dst += s->pic.linesize[0]; 365 buf += avctx->width; 366 } 367 memcpy(s->pic.data[1], s->pal, sizeof(s->pal)); 368 369 *data_size = sizeof(AVFrame); 370 *(AVFrame*)data = s->pic; 371 372 return avpkt->size; 373} 374 375static av_cold int dfa_decode_end(AVCodecContext *avctx) 376{ 377 DfaContext *s = avctx->priv_data; 378 379 if (s->pic.data[0]) 380 avctx->release_buffer(avctx, &s->pic); 381 382 av_freep(&s->frame_buf); 383 384 return 0; 385} 386 387AVCodec ff_dfa_decoder = { 388 .name = "dfa", 389 .type = AVMEDIA_TYPE_VIDEO, 390 .id = CODEC_ID_DFA, 391 .priv_data_size = sizeof(DfaContext), 392 .init = dfa_decode_init, 393 .close = dfa_decode_end, 394 .decode = dfa_decode_frame, 395 .capabilities = CODEC_CAP_DR1, 396 .long_name = NULL_IF_CONFIG_SMALL("Chronomaster DFA"), 397}; 398