| 1 | /* |
| 2 | * Electronic Arts TGV Video Decoder |
| 3 | * Copyright (c) 2007-2008 Peter Ross |
| 4 | * |
| 5 | * This file is part of FFmpeg. |
| 6 | * |
| 7 | * FFmpeg is free software; you can redistribute it and/or |
| 8 | * modify it under the terms of the GNU Lesser General Public |
| 9 | * License as published by the Free Software Foundation; either |
| 10 | * version 2.1 of the License, or (at your option) any later version. |
| 11 | * |
| 12 | * FFmpeg is distributed in the hope that it will be useful, |
| 13 | * but WITHOUT ANY WARRANTY; without even the implied warranty of |
| 14 | * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU |
| 15 | * Lesser General Public License for more details. |
| 16 | * |
| 17 | * You should have received a copy of the GNU Lesser General Public |
| 18 | * License along with FFmpeg; if not, write to the Free Software |
| 19 | * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA |
| 20 | */ |
| 21 | |
| 22 | /** |
| 23 | * @file |
| 24 | * Electronic Arts TGV Video Decoder |
| 25 | * by Peter Ross (pross@xvid.org) |
| 26 | * |
| 27 | * Technical details here: |
| 28 | * http://wiki.multimedia.cx/index.php?title=Electronic_Arts_TGV |
| 29 | */ |
| 30 | |
| 31 | #include "avcodec.h" |
| 32 | #define BITSTREAM_READER_LE |
| 33 | #include "get_bits.h" |
| 34 | #include "internal.h" |
| 35 | #include "libavutil/imgutils.h" |
| 36 | #include "libavutil/mem.h" |
| 37 | |
| 38 | #define EA_PREAMBLE_SIZE 8 |
| 39 | #define kVGT_TAG MKTAG('k', 'V', 'G', 'T') |
| 40 | |
| 41 | typedef struct TgvContext { |
| 42 | AVCodecContext *avctx; |
| 43 | AVFrame *last_frame; |
| 44 | uint8_t *frame_buffer; |
| 45 | int width,height; |
| 46 | uint32_t palette[AVPALETTE_COUNT]; |
| 47 | |
| 48 | int (*mv_codebook)[2]; |
| 49 | uint8_t (*block_codebook)[16]; |
| 50 | int num_mvs; ///< current length of mv_codebook |
| 51 | int num_blocks_packed; ///< current length of block_codebook |
| 52 | } TgvContext; |
| 53 | |
| 54 | static av_cold int tgv_decode_init(AVCodecContext *avctx) |
| 55 | { |
| 56 | TgvContext *s = avctx->priv_data; |
| 57 | s->avctx = avctx; |
| 58 | avctx->time_base = (AVRational){1, 15}; |
| 59 | avctx->pix_fmt = AV_PIX_FMT_PAL8; |
| 60 | |
| 61 | s->last_frame = av_frame_alloc(); |
| 62 | if (!s->last_frame) |
| 63 | return AVERROR(ENOMEM); |
| 64 | |
| 65 | return 0; |
| 66 | } |
| 67 | |
| 68 | /** |
| 69 | * Unpack buffer |
| 70 | * @return 0 on success, -1 on critical buffer underflow |
| 71 | */ |
| 72 | static int unpack(const uint8_t *src, const uint8_t *src_end, |
| 73 | uint8_t *dst, int width, int height) |
| 74 | { |
| 75 | uint8_t *dst_end = dst + width*height; |
| 76 | int size, size1, size2, offset, run; |
| 77 | uint8_t *dst_start = dst; |
| 78 | |
| 79 | if (src[0] & 0x01) |
| 80 | src += 5; |
| 81 | else |
| 82 | src += 2; |
| 83 | |
| 84 | if (src_end - src < 3) |
| 85 | return AVERROR_INVALIDDATA; |
| 86 | size = AV_RB24(src); |
| 87 | src += 3; |
| 88 | |
| 89 | while (size > 0 && src < src_end) { |
| 90 | |
| 91 | /* determine size1 and size2 */ |
| 92 | size1 = (src[0] & 3); |
| 93 | if (src[0] & 0x80) { // 1 |
| 94 | if (src[0] & 0x40 ) { // 11 |
| 95 | if (src[0] & 0x20) { // 111 |
| 96 | if (src[0] < 0xFC) // !(111111) |
| 97 | size1 = (((src[0] & 31) + 1) << 2); |
| 98 | src++; |
| 99 | size2 = 0; |
| 100 | } else { // 110 |
| 101 | offset = ((src[0] & 0x10) << 12) + AV_RB16(&src[1]) + 1; |
| 102 | size2 = ((src[0] & 0xC) << 6) + src[3] + 5; |
| 103 | src += 4; |
| 104 | } |
| 105 | } else { // 10 |
| 106 | size1 = ((src[1] & 0xC0) >> 6); |
| 107 | offset = (AV_RB16(&src[1]) & 0x3FFF) + 1; |
| 108 | size2 = (src[0] & 0x3F) + 4; |
| 109 | src += 3; |
| 110 | } |
| 111 | } else { // 0 |
| 112 | offset = ((src[0] & 0x60) << 3) + src[1] + 1; |
| 113 | size2 = ((src[0] & 0x1C) >> 2) + 3; |
| 114 | src += 2; |
| 115 | } |
| 116 | |
| 117 | |
| 118 | /* fetch strip from src */ |
| 119 | if (size1 > src_end - src) |
| 120 | break; |
| 121 | |
| 122 | if (size1 > 0) { |
| 123 | size -= size1; |
| 124 | run = FFMIN(size1, dst_end - dst); |
| 125 | memcpy(dst, src, run); |
| 126 | dst += run; |
| 127 | src += run; |
| 128 | } |
| 129 | |
| 130 | if (size2 > 0) { |
| 131 | if (dst - dst_start < offset) |
| 132 | return 0; |
| 133 | size -= size2; |
| 134 | run = FFMIN(size2, dst_end - dst); |
| 135 | av_memcpy_backptr(dst, offset, run); |
| 136 | dst += run; |
| 137 | } |
| 138 | } |
| 139 | |
| 140 | return 0; |
| 141 | } |
| 142 | |
| 143 | /** |
| 144 | * Decode inter-frame |
| 145 | * @return 0 on success, -1 on critical buffer underflow |
| 146 | */ |
| 147 | static int tgv_decode_inter(TgvContext *s, AVFrame *frame, |
| 148 | const uint8_t *buf, const uint8_t *buf_end) |
| 149 | { |
| 150 | int num_mvs; |
| 151 | int num_blocks_raw; |
| 152 | int num_blocks_packed; |
| 153 | int vector_bits; |
| 154 | int i,j,x,y; |
| 155 | GetBitContext gb; |
| 156 | int mvbits; |
| 157 | const uint8_t *blocks_raw; |
| 158 | |
| 159 | if(buf_end - buf < 12) |
| 160 | return AVERROR_INVALIDDATA; |
| 161 | |
| 162 | num_mvs = AV_RL16(&buf[0]); |
| 163 | num_blocks_raw = AV_RL16(&buf[2]); |
| 164 | num_blocks_packed = AV_RL16(&buf[4]); |
| 165 | vector_bits = AV_RL16(&buf[6]); |
| 166 | buf += 12; |
| 167 | |
| 168 | if (vector_bits > MIN_CACHE_BITS || !vector_bits) { |
| 169 | av_log(s->avctx, AV_LOG_ERROR, |
| 170 | "Invalid value for motion vector bits: %d\n", vector_bits); |
| 171 | return AVERROR_INVALIDDATA; |
| 172 | } |
| 173 | |
| 174 | /* allocate codebook buffers as necessary */ |
| 175 | if (num_mvs > s->num_mvs) { |
| 176 | if (av_reallocp_array(&s->mv_codebook, num_mvs, sizeof(*s->mv_codebook))) { |
| 177 | s->num_mvs = 0; |
| 178 | return AVERROR(ENOMEM); |
| 179 | } |
| 180 | s->num_mvs = num_mvs; |
| 181 | } |
| 182 | |
| 183 | if (num_blocks_packed > s->num_blocks_packed) { |
| 184 | int err; |
| 185 | if ((err = av_reallocp(&s->block_codebook, num_blocks_packed * 16)) < 0) { |
| 186 | s->num_blocks_packed = 0; |
| 187 | return err; |
| 188 | } |
| 189 | s->num_blocks_packed = num_blocks_packed; |
| 190 | } |
| 191 | |
| 192 | /* read motion vectors */ |
| 193 | mvbits = (num_mvs * 2 * 10 + 31) & ~31; |
| 194 | |
| 195 | if (buf_end - buf < (mvbits>>3) + 16*num_blocks_raw + 8*num_blocks_packed) |
| 196 | return AVERROR_INVALIDDATA; |
| 197 | |
| 198 | init_get_bits(&gb, buf, mvbits); |
| 199 | for (i = 0; i < num_mvs; i++) { |
| 200 | s->mv_codebook[i][0] = get_sbits(&gb, 10); |
| 201 | s->mv_codebook[i][1] = get_sbits(&gb, 10); |
| 202 | } |
| 203 | buf += mvbits >> 3; |
| 204 | |
| 205 | /* note ptr to uncompressed blocks */ |
| 206 | blocks_raw = buf; |
| 207 | buf += num_blocks_raw * 16; |
| 208 | |
| 209 | /* read compressed blocks */ |
| 210 | init_get_bits(&gb, buf, (buf_end - buf) << 3); |
| 211 | for (i = 0; i < num_blocks_packed; i++) { |
| 212 | int tmp[4]; |
| 213 | for (j = 0; j < 4; j++) |
| 214 | tmp[j] = get_bits(&gb, 8); |
| 215 | for (j = 0; j < 16; j++) |
| 216 | s->block_codebook[i][15-j] = tmp[get_bits(&gb, 2)]; |
| 217 | } |
| 218 | |
| 219 | if (get_bits_left(&gb) < vector_bits * |
| 220 | (s->avctx->height / 4) * (s->avctx->width / 4)) |
| 221 | return AVERROR_INVALIDDATA; |
| 222 | |
| 223 | /* read vectors and build frame */ |
| 224 | for (y = 0; y < s->avctx->height / 4; y++) |
| 225 | for (x = 0; x < s->avctx->width / 4; x++) { |
| 226 | unsigned int vector = get_bits(&gb, vector_bits); |
| 227 | const uint8_t *src; |
| 228 | int src_stride; |
| 229 | |
| 230 | if (vector < num_mvs) { |
| 231 | int mx = x * 4 + s->mv_codebook[vector][0]; |
| 232 | int my = y * 4 + s->mv_codebook[vector][1]; |
| 233 | |
| 234 | if (mx < 0 || mx + 4 > s->avctx->width || |
| 235 | my < 0 || my + 4 > s->avctx->height) { |
| 236 | av_log(s->avctx, AV_LOG_ERROR, "MV %d %d out of picture\n", mx, my); |
| 237 | continue; |
| 238 | } |
| 239 | |
| 240 | src = s->last_frame->data[0] + mx + my * s->last_frame->linesize[0]; |
| 241 | src_stride = s->last_frame->linesize[0]; |
| 242 | } else { |
| 243 | int offset = vector - num_mvs; |
| 244 | if (offset < num_blocks_raw) |
| 245 | src = blocks_raw + 16*offset; |
| 246 | else if (offset - num_blocks_raw < num_blocks_packed) |
| 247 | src = s->block_codebook[offset - num_blocks_raw]; |
| 248 | else |
| 249 | continue; |
| 250 | src_stride = 4; |
| 251 | } |
| 252 | |
| 253 | for (j = 0; j < 4; j++) |
| 254 | for (i = 0; i < 4; i++) |
| 255 | frame->data[0][(y * 4 + j) * frame->linesize[0] + (x * 4 + i)] = |
| 256 | src[j * src_stride + i]; |
| 257 | } |
| 258 | |
| 259 | return 0; |
| 260 | } |
| 261 | |
| 262 | static int tgv_decode_frame(AVCodecContext *avctx, |
| 263 | void *data, int *got_frame, |
| 264 | AVPacket *avpkt) |
| 265 | { |
| 266 | const uint8_t *buf = avpkt->data; |
| 267 | int buf_size = avpkt->size; |
| 268 | TgvContext *s = avctx->priv_data; |
| 269 | const uint8_t *buf_end = buf + buf_size; |
| 270 | AVFrame *frame = data; |
| 271 | int chunk_type, ret; |
| 272 | |
| 273 | if (buf_end - buf < EA_PREAMBLE_SIZE) |
| 274 | return AVERROR_INVALIDDATA; |
| 275 | |
| 276 | chunk_type = AV_RL32(&buf[0]); |
| 277 | buf += EA_PREAMBLE_SIZE; |
| 278 | |
| 279 | if (chunk_type == kVGT_TAG) { |
| 280 | int pal_count, i; |
| 281 | if(buf_end - buf < 12) { |
| 282 | av_log(avctx, AV_LOG_WARNING, "truncated header\n"); |
| 283 | return AVERROR_INVALIDDATA; |
| 284 | } |
| 285 | |
| 286 | s->width = AV_RL16(&buf[0]); |
| 287 | s->height = AV_RL16(&buf[2]); |
| 288 | if (s->avctx->width != s->width || s->avctx->height != s->height) { |
| 289 | av_freep(&s->frame_buffer); |
| 290 | av_frame_unref(s->last_frame); |
| 291 | if ((ret = ff_set_dimensions(s->avctx, s->width, s->height)) < 0) |
| 292 | return ret; |
| 293 | } |
| 294 | |
| 295 | pal_count = AV_RL16(&buf[6]); |
| 296 | buf += 12; |
| 297 | for(i = 0; i < pal_count && i < AVPALETTE_COUNT && buf_end - buf >= 3; i++) { |
| 298 | s->palette[i] = 0xFFU << 24 | AV_RB24(buf); |
| 299 | buf += 3; |
| 300 | } |
| 301 | } |
| 302 | |
| 303 | if ((ret = ff_get_buffer(avctx, frame, AV_GET_BUFFER_FLAG_REF)) < 0) |
| 304 | return ret; |
| 305 | |
| 306 | memcpy(frame->data[1], s->palette, AVPALETTE_SIZE); |
| 307 | |
| 308 | if (chunk_type == kVGT_TAG) { |
| 309 | int y; |
| 310 | frame->key_frame = 1; |
| 311 | frame->pict_type = AV_PICTURE_TYPE_I; |
| 312 | |
| 313 | if (!s->frame_buffer && |
| 314 | !(s->frame_buffer = av_mallocz(s->width * s->height))) |
| 315 | return AVERROR(ENOMEM); |
| 316 | |
| 317 | if (unpack(buf, buf_end, s->frame_buffer, s->avctx->width, s->avctx->height) < 0) { |
| 318 | av_log(avctx, AV_LOG_WARNING, "truncated intra frame\n"); |
| 319 | return AVERROR_INVALIDDATA; |
| 320 | } |
| 321 | for (y = 0; y < s->height; y++) |
| 322 | memcpy(frame->data[0] + y * frame->linesize[0], |
| 323 | s->frame_buffer + y * s->width, |
| 324 | s->width); |
| 325 | } else { |
| 326 | if (!s->last_frame->data[0]) { |
| 327 | av_log(avctx, AV_LOG_WARNING, "inter frame without corresponding intra frame\n"); |
| 328 | return buf_size; |
| 329 | } |
| 330 | frame->key_frame = 0; |
| 331 | frame->pict_type = AV_PICTURE_TYPE_P; |
| 332 | if (tgv_decode_inter(s, frame, buf, buf_end) < 0) { |
| 333 | av_log(avctx, AV_LOG_WARNING, "truncated inter frame\n"); |
| 334 | return AVERROR_INVALIDDATA; |
| 335 | } |
| 336 | } |
| 337 | |
| 338 | av_frame_unref(s->last_frame); |
| 339 | if ((ret = av_frame_ref(s->last_frame, frame)) < 0) |
| 340 | return ret; |
| 341 | |
| 342 | *got_frame = 1; |
| 343 | |
| 344 | return buf_size; |
| 345 | } |
| 346 | |
| 347 | static av_cold int tgv_decode_end(AVCodecContext *avctx) |
| 348 | { |
| 349 | TgvContext *s = avctx->priv_data; |
| 350 | av_frame_free(&s->last_frame); |
| 351 | av_freep(&s->frame_buffer); |
| 352 | av_free(s->mv_codebook); |
| 353 | av_free(s->block_codebook); |
| 354 | return 0; |
| 355 | } |
| 356 | |
| 357 | AVCodec ff_eatgv_decoder = { |
| 358 | .name = "eatgv", |
| 359 | .long_name = NULL_IF_CONFIG_SMALL("Electronic Arts TGV video"), |
| 360 | .type = AVMEDIA_TYPE_VIDEO, |
| 361 | .id = AV_CODEC_ID_TGV, |
| 362 | .priv_data_size = sizeof(TgvContext), |
| 363 | .init = tgv_decode_init, |
| 364 | .close = tgv_decode_end, |
| 365 | .decode = tgv_decode_frame, |
| 366 | .capabilities = CODEC_CAP_DR1, |
| 367 | }; |