| 1 | /* |
| 2 | * KMVC decoder |
| 3 | * Copyright (c) 2006 Konstantin Shishkov |
| 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 Street, Fifth Floor, Boston, MA 02110-1301 USA |
| 20 | */ |
| 21 | |
| 22 | /** |
| 23 | * @file |
| 24 | * Karl Morton's Video Codec decoder |
| 25 | */ |
| 26 | |
| 27 | #include <stdio.h> |
| 28 | #include <stdlib.h> |
| 29 | |
| 30 | #include "avcodec.h" |
| 31 | #include "bytestream.h" |
| 32 | #include "internal.h" |
| 33 | #include "libavutil/common.h" |
| 34 | |
| 35 | #define KMVC_KEYFRAME 0x80 |
| 36 | #define KMVC_PALETTE 0x40 |
| 37 | #define KMVC_METHOD 0x0F |
| 38 | #define MAX_PALSIZE 256 |
| 39 | |
| 40 | /* |
| 41 | * Decoder context |
| 42 | */ |
| 43 | typedef struct KmvcContext { |
| 44 | AVCodecContext *avctx; |
| 45 | |
| 46 | int setpal; |
| 47 | int palsize; |
| 48 | uint32_t pal[MAX_PALSIZE]; |
| 49 | uint8_t *cur, *prev; |
| 50 | uint8_t frm0[320 * 200], frm1[320 * 200]; |
| 51 | GetByteContext g; |
| 52 | } KmvcContext; |
| 53 | |
| 54 | typedef struct BitBuf { |
| 55 | int bits; |
| 56 | int bitbuf; |
| 57 | } BitBuf; |
| 58 | |
| 59 | #define BLK(data, x, y) data[av_clip((x) + (y) * 320, 0, 320 * 200 -1)] |
| 60 | |
| 61 | #define kmvc_init_getbits(bb, g) bb.bits = 7; bb.bitbuf = bytestream2_get_byte(g); |
| 62 | |
| 63 | #define kmvc_getbit(bb, g, res) {\ |
| 64 | res = 0; \ |
| 65 | if (bb.bitbuf & (1 << bb.bits)) res = 1; \ |
| 66 | bb.bits--; \ |
| 67 | if(bb.bits == -1) { \ |
| 68 | bb.bitbuf = bytestream2_get_byte(g); \ |
| 69 | bb.bits = 7; \ |
| 70 | } \ |
| 71 | } |
| 72 | |
| 73 | static int kmvc_decode_intra_8x8(KmvcContext * ctx, int w, int h) |
| 74 | { |
| 75 | BitBuf bb; |
| 76 | int res, val; |
| 77 | int i, j; |
| 78 | int bx, by; |
| 79 | int l0x, l1x, l0y, l1y; |
| 80 | int mx, my; |
| 81 | |
| 82 | kmvc_init_getbits(bb, &ctx->g); |
| 83 | |
| 84 | for (by = 0; by < h; by += 8) |
| 85 | for (bx = 0; bx < w; bx += 8) { |
| 86 | if (!bytestream2_get_bytes_left(&ctx->g)) { |
| 87 | av_log(ctx->avctx, AV_LOG_ERROR, "Data overrun\n"); |
| 88 | return AVERROR_INVALIDDATA; |
| 89 | } |
| 90 | kmvc_getbit(bb, &ctx->g, res); |
| 91 | if (!res) { // fill whole 8x8 block |
| 92 | val = bytestream2_get_byte(&ctx->g); |
| 93 | for (i = 0; i < 64; i++) |
| 94 | BLK(ctx->cur, bx + (i & 0x7), by + (i >> 3)) = val; |
| 95 | } else { // handle four 4x4 subblocks |
| 96 | for (i = 0; i < 4; i++) { |
| 97 | l0x = bx + (i & 1) * 4; |
| 98 | l0y = by + (i & 2) * 2; |
| 99 | kmvc_getbit(bb, &ctx->g, res); |
| 100 | if (!res) { |
| 101 | kmvc_getbit(bb, &ctx->g, res); |
| 102 | if (!res) { // fill whole 4x4 block |
| 103 | val = bytestream2_get_byte(&ctx->g); |
| 104 | for (j = 0; j < 16; j++) |
| 105 | BLK(ctx->cur, l0x + (j & 3), l0y + (j >> 2)) = val; |
| 106 | } else { // copy block from already decoded place |
| 107 | val = bytestream2_get_byte(&ctx->g); |
| 108 | mx = val & 0xF; |
| 109 | my = val >> 4; |
| 110 | if ((l0x-mx) + 320*(l0y-my) < 0 || (l0x-mx) + 320*(l0y-my) > 320*197 - 4) { |
| 111 | av_log(ctx->avctx, AV_LOG_ERROR, "Invalid MV\n"); |
| 112 | return AVERROR_INVALIDDATA; |
| 113 | } |
| 114 | for (j = 0; j < 16; j++) |
| 115 | BLK(ctx->cur, l0x + (j & 3), l0y + (j >> 2)) = |
| 116 | BLK(ctx->cur, l0x + (j & 3) - mx, l0y + (j >> 2) - my); |
| 117 | } |
| 118 | } else { // descend to 2x2 sub-sub-blocks |
| 119 | for (j = 0; j < 4; j++) { |
| 120 | l1x = l0x + (j & 1) * 2; |
| 121 | l1y = l0y + (j & 2); |
| 122 | kmvc_getbit(bb, &ctx->g, res); |
| 123 | if (!res) { |
| 124 | kmvc_getbit(bb, &ctx->g, res); |
| 125 | if (!res) { // fill whole 2x2 block |
| 126 | val = bytestream2_get_byte(&ctx->g); |
| 127 | BLK(ctx->cur, l1x, l1y) = val; |
| 128 | BLK(ctx->cur, l1x + 1, l1y) = val; |
| 129 | BLK(ctx->cur, l1x, l1y + 1) = val; |
| 130 | BLK(ctx->cur, l1x + 1, l1y + 1) = val; |
| 131 | } else { // copy block from already decoded place |
| 132 | val = bytestream2_get_byte(&ctx->g); |
| 133 | mx = val & 0xF; |
| 134 | my = val >> 4; |
| 135 | if ((l1x-mx) + 320*(l1y-my) < 0 || (l1x-mx) + 320*(l1y-my) > 320*199 - 2) { |
| 136 | av_log(ctx->avctx, AV_LOG_ERROR, "Invalid MV\n"); |
| 137 | return AVERROR_INVALIDDATA; |
| 138 | } |
| 139 | BLK(ctx->cur, l1x, l1y) = BLK(ctx->cur, l1x - mx, l1y - my); |
| 140 | BLK(ctx->cur, l1x + 1, l1y) = |
| 141 | BLK(ctx->cur, l1x + 1 - mx, l1y - my); |
| 142 | BLK(ctx->cur, l1x, l1y + 1) = |
| 143 | BLK(ctx->cur, l1x - mx, l1y + 1 - my); |
| 144 | BLK(ctx->cur, l1x + 1, l1y + 1) = |
| 145 | BLK(ctx->cur, l1x + 1 - mx, l1y + 1 - my); |
| 146 | } |
| 147 | } else { // read values for block |
| 148 | BLK(ctx->cur, l1x, l1y) = bytestream2_get_byte(&ctx->g); |
| 149 | BLK(ctx->cur, l1x + 1, l1y) = bytestream2_get_byte(&ctx->g); |
| 150 | BLK(ctx->cur, l1x, l1y + 1) = bytestream2_get_byte(&ctx->g); |
| 151 | BLK(ctx->cur, l1x + 1, l1y + 1) = bytestream2_get_byte(&ctx->g); |
| 152 | } |
| 153 | } |
| 154 | } |
| 155 | } |
| 156 | } |
| 157 | } |
| 158 | |
| 159 | return 0; |
| 160 | } |
| 161 | |
| 162 | static int kmvc_decode_inter_8x8(KmvcContext * ctx, int w, int h) |
| 163 | { |
| 164 | BitBuf bb; |
| 165 | int res, val; |
| 166 | int i, j; |
| 167 | int bx, by; |
| 168 | int l0x, l1x, l0y, l1y; |
| 169 | int mx, my; |
| 170 | |
| 171 | kmvc_init_getbits(bb, &ctx->g); |
| 172 | |
| 173 | for (by = 0; by < h; by += 8) |
| 174 | for (bx = 0; bx < w; bx += 8) { |
| 175 | kmvc_getbit(bb, &ctx->g, res); |
| 176 | if (!res) { |
| 177 | kmvc_getbit(bb, &ctx->g, res); |
| 178 | if (!res) { // fill whole 8x8 block |
| 179 | if (!bytestream2_get_bytes_left(&ctx->g)) { |
| 180 | av_log(ctx->avctx, AV_LOG_ERROR, "Data overrun\n"); |
| 181 | return AVERROR_INVALIDDATA; |
| 182 | } |
| 183 | val = bytestream2_get_byte(&ctx->g); |
| 184 | for (i = 0; i < 64; i++) |
| 185 | BLK(ctx->cur, bx + (i & 0x7), by + (i >> 3)) = val; |
| 186 | } else { // copy block from previous frame |
| 187 | for (i = 0; i < 64; i++) |
| 188 | BLK(ctx->cur, bx + (i & 0x7), by + (i >> 3)) = |
| 189 | BLK(ctx->prev, bx + (i & 0x7), by + (i >> 3)); |
| 190 | } |
| 191 | } else { // handle four 4x4 subblocks |
| 192 | if (!bytestream2_get_bytes_left(&ctx->g)) { |
| 193 | av_log(ctx->avctx, AV_LOG_ERROR, "Data overrun\n"); |
| 194 | return AVERROR_INVALIDDATA; |
| 195 | } |
| 196 | for (i = 0; i < 4; i++) { |
| 197 | l0x = bx + (i & 1) * 4; |
| 198 | l0y = by + (i & 2) * 2; |
| 199 | kmvc_getbit(bb, &ctx->g, res); |
| 200 | if (!res) { |
| 201 | kmvc_getbit(bb, &ctx->g, res); |
| 202 | if (!res) { // fill whole 4x4 block |
| 203 | val = bytestream2_get_byte(&ctx->g); |
| 204 | for (j = 0; j < 16; j++) |
| 205 | BLK(ctx->cur, l0x + (j & 3), l0y + (j >> 2)) = val; |
| 206 | } else { // copy block |
| 207 | val = bytestream2_get_byte(&ctx->g); |
| 208 | mx = (val & 0xF) - 8; |
| 209 | my = (val >> 4) - 8; |
| 210 | if ((l0x+mx) + 320*(l0y+my) < 0 || (l0x+mx) + 320*(l0y+my) > 320*197 - 4) { |
| 211 | av_log(ctx->avctx, AV_LOG_ERROR, "Invalid MV\n"); |
| 212 | return AVERROR_INVALIDDATA; |
| 213 | } |
| 214 | for (j = 0; j < 16; j++) |
| 215 | BLK(ctx->cur, l0x + (j & 3), l0y + (j >> 2)) = |
| 216 | BLK(ctx->prev, l0x + (j & 3) + mx, l0y + (j >> 2) + my); |
| 217 | } |
| 218 | } else { // descend to 2x2 sub-sub-blocks |
| 219 | for (j = 0; j < 4; j++) { |
| 220 | l1x = l0x + (j & 1) * 2; |
| 221 | l1y = l0y + (j & 2); |
| 222 | kmvc_getbit(bb, &ctx->g, res); |
| 223 | if (!res) { |
| 224 | kmvc_getbit(bb, &ctx->g, res); |
| 225 | if (!res) { // fill whole 2x2 block |
| 226 | val = bytestream2_get_byte(&ctx->g); |
| 227 | BLK(ctx->cur, l1x, l1y) = val; |
| 228 | BLK(ctx->cur, l1x + 1, l1y) = val; |
| 229 | BLK(ctx->cur, l1x, l1y + 1) = val; |
| 230 | BLK(ctx->cur, l1x + 1, l1y + 1) = val; |
| 231 | } else { // copy block |
| 232 | val = bytestream2_get_byte(&ctx->g); |
| 233 | mx = (val & 0xF) - 8; |
| 234 | my = (val >> 4) - 8; |
| 235 | if ((l1x+mx) + 320*(l1y+my) < 0 || (l1x+mx) + 320*(l1y+my) > 320*199 - 2) { |
| 236 | av_log(ctx->avctx, AV_LOG_ERROR, "Invalid MV\n"); |
| 237 | return AVERROR_INVALIDDATA; |
| 238 | } |
| 239 | BLK(ctx->cur, l1x, l1y) = BLK(ctx->prev, l1x + mx, l1y + my); |
| 240 | BLK(ctx->cur, l1x + 1, l1y) = |
| 241 | BLK(ctx->prev, l1x + 1 + mx, l1y + my); |
| 242 | BLK(ctx->cur, l1x, l1y + 1) = |
| 243 | BLK(ctx->prev, l1x + mx, l1y + 1 + my); |
| 244 | BLK(ctx->cur, l1x + 1, l1y + 1) = |
| 245 | BLK(ctx->prev, l1x + 1 + mx, l1y + 1 + my); |
| 246 | } |
| 247 | } else { // read values for block |
| 248 | BLK(ctx->cur, l1x, l1y) = bytestream2_get_byte(&ctx->g); |
| 249 | BLK(ctx->cur, l1x + 1, l1y) = bytestream2_get_byte(&ctx->g); |
| 250 | BLK(ctx->cur, l1x, l1y + 1) = bytestream2_get_byte(&ctx->g); |
| 251 | BLK(ctx->cur, l1x + 1, l1y + 1) = bytestream2_get_byte(&ctx->g); |
| 252 | } |
| 253 | } |
| 254 | } |
| 255 | } |
| 256 | } |
| 257 | } |
| 258 | |
| 259 | return 0; |
| 260 | } |
| 261 | |
| 262 | static int decode_frame(AVCodecContext * avctx, void *data, int *got_frame, |
| 263 | AVPacket *avpkt) |
| 264 | { |
| 265 | KmvcContext *const ctx = avctx->priv_data; |
| 266 | AVFrame *frame = data; |
| 267 | uint8_t *out, *src; |
| 268 | int i, ret; |
| 269 | int header; |
| 270 | int blocksize; |
| 271 | const uint8_t *pal = av_packet_get_side_data(avpkt, AV_PKT_DATA_PALETTE, NULL); |
| 272 | |
| 273 | bytestream2_init(&ctx->g, avpkt->data, avpkt->size); |
| 274 | |
| 275 | if ((ret = ff_get_buffer(avctx, frame, 0)) < 0) |
| 276 | return ret; |
| 277 | |
| 278 | header = bytestream2_get_byte(&ctx->g); |
| 279 | |
| 280 | /* blocksize 127 is really palette change event */ |
| 281 | if (bytestream2_peek_byte(&ctx->g) == 127) { |
| 282 | bytestream2_skip(&ctx->g, 3); |
| 283 | for (i = 0; i < 127; i++) { |
| 284 | ctx->pal[i + (header & 0x81)] = 0xFFU << 24 | bytestream2_get_be24(&ctx->g); |
| 285 | bytestream2_skip(&ctx->g, 1); |
| 286 | } |
| 287 | bytestream2_seek(&ctx->g, -127 * 4 - 3, SEEK_CUR); |
| 288 | } |
| 289 | |
| 290 | if (header & KMVC_KEYFRAME) { |
| 291 | frame->key_frame = 1; |
| 292 | frame->pict_type = AV_PICTURE_TYPE_I; |
| 293 | } else { |
| 294 | frame->key_frame = 0; |
| 295 | frame->pict_type = AV_PICTURE_TYPE_P; |
| 296 | } |
| 297 | |
| 298 | if (header & KMVC_PALETTE) { |
| 299 | frame->palette_has_changed = 1; |
| 300 | // palette starts from index 1 and has 127 entries |
| 301 | for (i = 1; i <= ctx->palsize; i++) { |
| 302 | ctx->pal[i] = 0xFFU << 24 | bytestream2_get_be24(&ctx->g); |
| 303 | } |
| 304 | } |
| 305 | |
| 306 | if (pal) { |
| 307 | frame->palette_has_changed = 1; |
| 308 | memcpy(ctx->pal, pal, AVPALETTE_SIZE); |
| 309 | } |
| 310 | |
| 311 | if (ctx->setpal) { |
| 312 | ctx->setpal = 0; |
| 313 | frame->palette_has_changed = 1; |
| 314 | } |
| 315 | |
| 316 | /* make the palette available on the way out */ |
| 317 | memcpy(frame->data[1], ctx->pal, 1024); |
| 318 | |
| 319 | blocksize = bytestream2_get_byte(&ctx->g); |
| 320 | |
| 321 | if (blocksize != 8 && blocksize != 127) { |
| 322 | av_log(avctx, AV_LOG_ERROR, "Block size = %i\n", blocksize); |
| 323 | return AVERROR_INVALIDDATA; |
| 324 | } |
| 325 | memset(ctx->cur, 0, 320 * 200); |
| 326 | switch (header & KMVC_METHOD) { |
| 327 | case 0: |
| 328 | case 1: // used in palette changed event |
| 329 | memcpy(ctx->cur, ctx->prev, 320 * 200); |
| 330 | break; |
| 331 | case 3: |
| 332 | kmvc_decode_intra_8x8(ctx, avctx->width, avctx->height); |
| 333 | break; |
| 334 | case 4: |
| 335 | kmvc_decode_inter_8x8(ctx, avctx->width, avctx->height); |
| 336 | break; |
| 337 | default: |
| 338 | av_log(avctx, AV_LOG_ERROR, "Unknown compression method %i\n", header & KMVC_METHOD); |
| 339 | return AVERROR_INVALIDDATA; |
| 340 | } |
| 341 | |
| 342 | out = frame->data[0]; |
| 343 | src = ctx->cur; |
| 344 | for (i = 0; i < avctx->height; i++) { |
| 345 | memcpy(out, src, avctx->width); |
| 346 | src += 320; |
| 347 | out += frame->linesize[0]; |
| 348 | } |
| 349 | |
| 350 | /* flip buffers */ |
| 351 | if (ctx->cur == ctx->frm0) { |
| 352 | ctx->cur = ctx->frm1; |
| 353 | ctx->prev = ctx->frm0; |
| 354 | } else { |
| 355 | ctx->cur = ctx->frm0; |
| 356 | ctx->prev = ctx->frm1; |
| 357 | } |
| 358 | |
| 359 | *got_frame = 1; |
| 360 | |
| 361 | /* always report that the buffer was completely consumed */ |
| 362 | return avpkt->size; |
| 363 | } |
| 364 | |
| 365 | |
| 366 | |
| 367 | /* |
| 368 | * Init kmvc decoder |
| 369 | */ |
| 370 | static av_cold int decode_init(AVCodecContext * avctx) |
| 371 | { |
| 372 | KmvcContext *const c = avctx->priv_data; |
| 373 | int i; |
| 374 | |
| 375 | c->avctx = avctx; |
| 376 | |
| 377 | if (avctx->width > 320 || avctx->height > 200) { |
| 378 | av_log(avctx, AV_LOG_ERROR, "KMVC supports frames <= 320x200\n"); |
| 379 | return AVERROR(EINVAL); |
| 380 | } |
| 381 | |
| 382 | c->cur = c->frm0; |
| 383 | c->prev = c->frm1; |
| 384 | |
| 385 | for (i = 0; i < 256; i++) { |
| 386 | c->pal[i] = 0xFFU << 24 | i * 0x10101; |
| 387 | } |
| 388 | |
| 389 | if (avctx->extradata_size < 12) { |
| 390 | av_log(avctx, AV_LOG_WARNING, |
| 391 | "Extradata missing, decoding may not work properly...\n"); |
| 392 | c->palsize = 127; |
| 393 | } else { |
| 394 | c->palsize = AV_RL16(avctx->extradata + 10); |
| 395 | if (c->palsize >= (unsigned)MAX_PALSIZE) { |
| 396 | c->palsize = 127; |
| 397 | av_log(avctx, AV_LOG_ERROR, "KMVC palette too large\n"); |
| 398 | return AVERROR_INVALIDDATA; |
| 399 | } |
| 400 | } |
| 401 | |
| 402 | if (avctx->extradata_size == 1036) { // palette in extradata |
| 403 | uint8_t *src = avctx->extradata + 12; |
| 404 | for (i = 0; i < 256; i++) { |
| 405 | c->pal[i] = AV_RL32(src); |
| 406 | src += 4; |
| 407 | } |
| 408 | c->setpal = 1; |
| 409 | } |
| 410 | |
| 411 | avctx->pix_fmt = AV_PIX_FMT_PAL8; |
| 412 | |
| 413 | return 0; |
| 414 | } |
| 415 | |
| 416 | AVCodec ff_kmvc_decoder = { |
| 417 | .name = "kmvc", |
| 418 | .long_name = NULL_IF_CONFIG_SMALL("Karl Morton's video codec"), |
| 419 | .type = AVMEDIA_TYPE_VIDEO, |
| 420 | .id = AV_CODEC_ID_KMVC, |
| 421 | .priv_data_size = sizeof(KmvcContext), |
| 422 | .init = decode_init, |
| 423 | .decode = decode_frame, |
| 424 | .capabilities = CODEC_CAP_DR1, |
| 425 | }; |