| 1 | /* |
| 2 | * GIF decoder |
| 3 | * Copyright (c) 2003 Fabrice Bellard |
| 4 | * Copyright (c) 2006 Baptiste Coudurier |
| 5 | * Copyright (c) 2012 Vitaliy E Sugrobov |
| 6 | * |
| 7 | * This file is part of FFmpeg. |
| 8 | * |
| 9 | * FFmpeg is free software; you can redistribute it and/or |
| 10 | * modify it under the terms of the GNU Lesser General Public |
| 11 | * License as published by the Free Software Foundation; either |
| 12 | * version 2.1 of the License, or (at your option) any later version. |
| 13 | * |
| 14 | * FFmpeg is distributed in the hope that it will be useful, |
| 15 | * but WITHOUT ANY WARRANTY; without even the implied warranty of |
| 16 | * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU |
| 17 | * Lesser General Public License for more details. |
| 18 | * |
| 19 | * You should have received a copy of the GNU Lesser General Public |
| 20 | * License along with FFmpeg; if not, write to the Free Software |
| 21 | * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA |
| 22 | */ |
| 23 | |
| 24 | #include "libavutil/imgutils.h" |
| 25 | #include "libavutil/opt.h" |
| 26 | #include "avcodec.h" |
| 27 | #include "bytestream.h" |
| 28 | #include "internal.h" |
| 29 | #include "lzw.h" |
| 30 | #include "gif.h" |
| 31 | |
| 32 | /* This value is intentionally set to "transparent white" color. |
| 33 | * It is much better to have white background instead of black |
| 34 | * when gif image converted to format which not support transparency. |
| 35 | */ |
| 36 | #define GIF_TRANSPARENT_COLOR 0x00ffffff |
| 37 | |
| 38 | typedef struct GifState { |
| 39 | const AVClass *class; |
| 40 | AVFrame *frame; |
| 41 | int screen_width; |
| 42 | int screen_height; |
| 43 | int has_global_palette; |
| 44 | int bits_per_pixel; |
| 45 | uint32_t bg_color; |
| 46 | int background_color_index; |
| 47 | int transparent_color_index; |
| 48 | int color_resolution; |
| 49 | /* intermediate buffer for storing color indices |
| 50 | * obtained from lzw-encoded data stream */ |
| 51 | uint8_t *idx_line; |
| 52 | int idx_line_size; |
| 53 | |
| 54 | /* after the frame is displayed, the disposal method is used */ |
| 55 | int gce_prev_disposal; |
| 56 | int gce_disposal; |
| 57 | /* rectangle describing area that must be disposed */ |
| 58 | int gce_l, gce_t, gce_w, gce_h; |
| 59 | /* depending on disposal method we store either part of the image |
| 60 | * drawn on the canvas or background color that |
| 61 | * should be used upon disposal */ |
| 62 | uint32_t * stored_img; |
| 63 | int stored_img_size; |
| 64 | int stored_bg_color; |
| 65 | |
| 66 | GetByteContext gb; |
| 67 | LZWState *lzw; |
| 68 | |
| 69 | /* aux buffers */ |
| 70 | uint32_t global_palette[256]; |
| 71 | uint32_t local_palette[256]; |
| 72 | |
| 73 | AVCodecContext *avctx; |
| 74 | int keyframe; |
| 75 | int keyframe_ok; |
| 76 | int trans_color; /**< color value that is used instead of transparent color */ |
| 77 | } GifState; |
| 78 | |
| 79 | static void gif_read_palette(GifState *s, uint32_t *pal, int nb) |
| 80 | { |
| 81 | int i; |
| 82 | |
| 83 | for (i = 0; i < nb; i++, pal++) |
| 84 | *pal = (0xffu << 24) | bytestream2_get_be24u(&s->gb); |
| 85 | } |
| 86 | |
| 87 | static void gif_fill(AVFrame *picture, uint32_t color) |
| 88 | { |
| 89 | uint32_t *p = (uint32_t *)picture->data[0]; |
| 90 | uint32_t *p_end = p + (picture->linesize[0] / sizeof(uint32_t)) * picture->height; |
| 91 | |
| 92 | for (; p < p_end; p++) |
| 93 | *p = color; |
| 94 | } |
| 95 | |
| 96 | static void gif_fill_rect(AVFrame *picture, uint32_t color, int l, int t, int w, int h) |
| 97 | { |
| 98 | const int linesize = picture->linesize[0] / sizeof(uint32_t); |
| 99 | const uint32_t *py = (uint32_t *)picture->data[0] + t * linesize; |
| 100 | const uint32_t *pr, *pb = py + h * linesize; |
| 101 | uint32_t *px; |
| 102 | |
| 103 | for (; py < pb; py += linesize) { |
| 104 | px = (uint32_t *)py + l; |
| 105 | pr = px + w; |
| 106 | |
| 107 | for (; px < pr; px++) |
| 108 | *px = color; |
| 109 | } |
| 110 | } |
| 111 | |
| 112 | static void gif_copy_img_rect(const uint32_t *src, uint32_t *dst, |
| 113 | int linesize, int l, int t, int w, int h) |
| 114 | { |
| 115 | const int y_start = t * linesize; |
| 116 | const uint32_t *src_px, |
| 117 | *src_py = src + y_start, |
| 118 | *dst_py = dst + y_start; |
| 119 | const uint32_t *src_pb = src_py + h * linesize; |
| 120 | uint32_t *dst_px; |
| 121 | |
| 122 | for (; src_py < src_pb; src_py += linesize, dst_py += linesize) { |
| 123 | src_px = src_py + l; |
| 124 | dst_px = (uint32_t *)dst_py + l; |
| 125 | |
| 126 | memcpy(dst_px, src_px, w * sizeof(uint32_t)); |
| 127 | } |
| 128 | } |
| 129 | |
| 130 | static int gif_read_image(GifState *s, AVFrame *frame) |
| 131 | { |
| 132 | int left, top, width, height, bits_per_pixel, code_size, flags, pw; |
| 133 | int is_interleaved, has_local_palette, y, pass, y1, linesize, pal_size; |
| 134 | uint32_t *ptr, *pal, *px, *pr, *ptr1; |
| 135 | int ret; |
| 136 | uint8_t *idx; |
| 137 | |
| 138 | /* At least 9 bytes of Image Descriptor. */ |
| 139 | if (bytestream2_get_bytes_left(&s->gb) < 9) |
| 140 | return AVERROR_INVALIDDATA; |
| 141 | |
| 142 | left = bytestream2_get_le16u(&s->gb); |
| 143 | top = bytestream2_get_le16u(&s->gb); |
| 144 | width = bytestream2_get_le16u(&s->gb); |
| 145 | height = bytestream2_get_le16u(&s->gb); |
| 146 | flags = bytestream2_get_byteu(&s->gb); |
| 147 | is_interleaved = flags & 0x40; |
| 148 | has_local_palette = flags & 0x80; |
| 149 | bits_per_pixel = (flags & 0x07) + 1; |
| 150 | |
| 151 | av_dlog(s->avctx, "image x=%d y=%d w=%d h=%d\n", left, top, width, height); |
| 152 | |
| 153 | if (has_local_palette) { |
| 154 | pal_size = 1 << bits_per_pixel; |
| 155 | |
| 156 | if (bytestream2_get_bytes_left(&s->gb) < pal_size * 3) |
| 157 | return AVERROR_INVALIDDATA; |
| 158 | |
| 159 | gif_read_palette(s, s->local_palette, pal_size); |
| 160 | pal = s->local_palette; |
| 161 | } else { |
| 162 | if (!s->has_global_palette) { |
| 163 | av_log(s->avctx, AV_LOG_ERROR, "picture doesn't have either global or local palette.\n"); |
| 164 | return AVERROR_INVALIDDATA; |
| 165 | } |
| 166 | |
| 167 | pal = s->global_palette; |
| 168 | } |
| 169 | |
| 170 | if (s->keyframe) { |
| 171 | if (s->transparent_color_index == -1 && s->has_global_palette) { |
| 172 | /* transparency wasn't set before the first frame, fill with background color */ |
| 173 | gif_fill(frame, s->bg_color); |
| 174 | } else { |
| 175 | /* otherwise fill with transparent color. |
| 176 | * this is necessary since by default picture filled with 0x80808080. */ |
| 177 | gif_fill(frame, s->trans_color); |
| 178 | } |
| 179 | } |
| 180 | |
| 181 | /* verify that all the image is inside the screen dimensions */ |
| 182 | if (!width || width > s->screen_width || left >= s->screen_width) { |
| 183 | av_log(s->avctx, AV_LOG_ERROR, "Invalid image width.\n"); |
| 184 | return AVERROR_INVALIDDATA; |
| 185 | } |
| 186 | if (!height || height > s->screen_height || top >= s->screen_height) { |
| 187 | av_log(s->avctx, AV_LOG_ERROR, "Invalid image height.\n"); |
| 188 | return AVERROR_INVALIDDATA; |
| 189 | } |
| 190 | if (left + width > s->screen_width) { |
| 191 | /* width must be kept around to avoid lzw vs line desync */ |
| 192 | pw = s->screen_width - left; |
| 193 | av_log(s->avctx, AV_LOG_WARNING, "Image too wide by %d, truncating.\n", |
| 194 | left + width - s->screen_width); |
| 195 | } else { |
| 196 | pw = width; |
| 197 | } |
| 198 | if (top + height > s->screen_height) { |
| 199 | /* we don't care about the extra invisible lines */ |
| 200 | av_log(s->avctx, AV_LOG_WARNING, "Image too high by %d, truncating.\n", |
| 201 | top + height - s->screen_height); |
| 202 | height = s->screen_height - top; |
| 203 | } |
| 204 | |
| 205 | /* process disposal method */ |
| 206 | if (s->gce_prev_disposal == GCE_DISPOSAL_BACKGROUND) { |
| 207 | gif_fill_rect(frame, s->stored_bg_color, s->gce_l, s->gce_t, s->gce_w, s->gce_h); |
| 208 | } else if (s->gce_prev_disposal == GCE_DISPOSAL_RESTORE) { |
| 209 | gif_copy_img_rect(s->stored_img, (uint32_t *)frame->data[0], |
| 210 | frame->linesize[0] / sizeof(uint32_t), s->gce_l, s->gce_t, s->gce_w, s->gce_h); |
| 211 | } |
| 212 | |
| 213 | s->gce_prev_disposal = s->gce_disposal; |
| 214 | |
| 215 | if (s->gce_disposal != GCE_DISPOSAL_NONE) { |
| 216 | s->gce_l = left; s->gce_t = top; |
| 217 | s->gce_w = pw; s->gce_h = height; |
| 218 | |
| 219 | if (s->gce_disposal == GCE_DISPOSAL_BACKGROUND) { |
| 220 | if (s->transparent_color_index >= 0) |
| 221 | s->stored_bg_color = s->trans_color; |
| 222 | else |
| 223 | s->stored_bg_color = s->bg_color; |
| 224 | } else if (s->gce_disposal == GCE_DISPOSAL_RESTORE) { |
| 225 | av_fast_malloc(&s->stored_img, &s->stored_img_size, frame->linesize[0] * frame->height); |
| 226 | if (!s->stored_img) |
| 227 | return AVERROR(ENOMEM); |
| 228 | |
| 229 | gif_copy_img_rect((uint32_t *)frame->data[0], s->stored_img, |
| 230 | frame->linesize[0] / sizeof(uint32_t), left, top, pw, height); |
| 231 | } |
| 232 | } |
| 233 | |
| 234 | /* Expect at least 2 bytes: 1 for lzw code size and 1 for block size. */ |
| 235 | if (bytestream2_get_bytes_left(&s->gb) < 2) |
| 236 | return AVERROR_INVALIDDATA; |
| 237 | |
| 238 | /* now get the image data */ |
| 239 | code_size = bytestream2_get_byteu(&s->gb); |
| 240 | if ((ret = ff_lzw_decode_init(s->lzw, code_size, s->gb.buffer, |
| 241 | bytestream2_get_bytes_left(&s->gb), FF_LZW_GIF)) < 0) { |
| 242 | av_log(s->avctx, AV_LOG_ERROR, "LZW init failed\n"); |
| 243 | return ret; |
| 244 | } |
| 245 | |
| 246 | /* read all the image */ |
| 247 | linesize = frame->linesize[0] / sizeof(uint32_t); |
| 248 | ptr1 = (uint32_t *)frame->data[0] + top * linesize + left; |
| 249 | ptr = ptr1; |
| 250 | pass = 0; |
| 251 | y1 = 0; |
| 252 | for (y = 0; y < height; y++) { |
| 253 | int count = ff_lzw_decode(s->lzw, s->idx_line, width); |
| 254 | if (count != width) { |
| 255 | if (count) |
| 256 | av_log(s->avctx, AV_LOG_ERROR, "LZW decode failed\n"); |
| 257 | goto decode_tail; |
| 258 | } |
| 259 | |
| 260 | pr = ptr + pw; |
| 261 | |
| 262 | for (px = ptr, idx = s->idx_line; px < pr; px++, idx++) { |
| 263 | if (*idx != s->transparent_color_index) |
| 264 | *px = pal[*idx]; |
| 265 | } |
| 266 | |
| 267 | if (is_interleaved) { |
| 268 | switch(pass) { |
| 269 | default: |
| 270 | case 0: |
| 271 | case 1: |
| 272 | y1 += 8; |
| 273 | ptr += linesize * 8; |
| 274 | break; |
| 275 | case 2: |
| 276 | y1 += 4; |
| 277 | ptr += linesize * 4; |
| 278 | break; |
| 279 | case 3: |
| 280 | y1 += 2; |
| 281 | ptr += linesize * 2; |
| 282 | break; |
| 283 | } |
| 284 | while (y1 >= height) { |
| 285 | y1 = 4 >> pass; |
| 286 | ptr = ptr1 + linesize * y1; |
| 287 | pass++; |
| 288 | } |
| 289 | } else { |
| 290 | ptr += linesize; |
| 291 | } |
| 292 | } |
| 293 | |
| 294 | decode_tail: |
| 295 | /* read the garbage data until end marker is found */ |
| 296 | ff_lzw_decode_tail(s->lzw); |
| 297 | |
| 298 | /* Graphic Control Extension's scope is single frame. |
| 299 | * Remove its influence. */ |
| 300 | s->transparent_color_index = -1; |
| 301 | s->gce_disposal = GCE_DISPOSAL_NONE; |
| 302 | |
| 303 | return 0; |
| 304 | } |
| 305 | |
| 306 | static int gif_read_extension(GifState *s) |
| 307 | { |
| 308 | int ext_code, ext_len, gce_flags, gce_transparent_index; |
| 309 | |
| 310 | /* There must be at least 2 bytes: |
| 311 | * 1 for extension label and 1 for extension length. */ |
| 312 | if (bytestream2_get_bytes_left(&s->gb) < 2) |
| 313 | return AVERROR_INVALIDDATA; |
| 314 | |
| 315 | ext_code = bytestream2_get_byteu(&s->gb); |
| 316 | ext_len = bytestream2_get_byteu(&s->gb); |
| 317 | |
| 318 | av_dlog(s->avctx, "ext_code=0x%x len=%d\n", ext_code, ext_len); |
| 319 | |
| 320 | switch(ext_code) { |
| 321 | case GIF_GCE_EXT_LABEL: |
| 322 | if (ext_len != 4) |
| 323 | goto discard_ext; |
| 324 | |
| 325 | /* We need at least 5 bytes more: 4 is for extension body |
| 326 | * and 1 for next block size. */ |
| 327 | if (bytestream2_get_bytes_left(&s->gb) < 5) |
| 328 | return AVERROR_INVALIDDATA; |
| 329 | |
| 330 | gce_flags = bytestream2_get_byteu(&s->gb); |
| 331 | bytestream2_skipu(&s->gb, 2); // delay during which the frame is shown |
| 332 | gce_transparent_index = bytestream2_get_byteu(&s->gb); |
| 333 | if (gce_flags & 0x01) |
| 334 | s->transparent_color_index = gce_transparent_index; |
| 335 | else |
| 336 | s->transparent_color_index = -1; |
| 337 | s->gce_disposal = (gce_flags >> 2) & 0x7; |
| 338 | |
| 339 | av_dlog(s->avctx, "gce_flags=%x tcolor=%d disposal=%d\n", |
| 340 | gce_flags, |
| 341 | s->transparent_color_index, s->gce_disposal); |
| 342 | |
| 343 | if (s->gce_disposal > 3) { |
| 344 | s->gce_disposal = GCE_DISPOSAL_NONE; |
| 345 | av_dlog(s->avctx, "invalid value in gce_disposal (%d). Using default value of 0.\n", ext_len); |
| 346 | } |
| 347 | |
| 348 | ext_len = bytestream2_get_byteu(&s->gb); |
| 349 | break; |
| 350 | } |
| 351 | |
| 352 | /* NOTE: many extension blocks can come after */ |
| 353 | discard_ext: |
| 354 | while (ext_len) { |
| 355 | /* There must be at least ext_len bytes and 1 for next block size byte. */ |
| 356 | if (bytestream2_get_bytes_left(&s->gb) < ext_len + 1) |
| 357 | return AVERROR_INVALIDDATA; |
| 358 | |
| 359 | bytestream2_skipu(&s->gb, ext_len); |
| 360 | ext_len = bytestream2_get_byteu(&s->gb); |
| 361 | |
| 362 | av_dlog(s->avctx, "ext_len1=%d\n", ext_len); |
| 363 | } |
| 364 | return 0; |
| 365 | } |
| 366 | |
| 367 | static int gif_read_header1(GifState *s) |
| 368 | { |
| 369 | uint8_t sig[6]; |
| 370 | int v, n; |
| 371 | int background_color_index; |
| 372 | |
| 373 | if (bytestream2_get_bytes_left(&s->gb) < 13) |
| 374 | return AVERROR_INVALIDDATA; |
| 375 | |
| 376 | /* read gif signature */ |
| 377 | bytestream2_get_bufferu(&s->gb, sig, 6); |
| 378 | if (memcmp(sig, gif87a_sig, 6) && |
| 379 | memcmp(sig, gif89a_sig, 6)) |
| 380 | return AVERROR_INVALIDDATA; |
| 381 | |
| 382 | /* read screen header */ |
| 383 | s->transparent_color_index = -1; |
| 384 | s->screen_width = bytestream2_get_le16u(&s->gb); |
| 385 | s->screen_height = bytestream2_get_le16u(&s->gb); |
| 386 | |
| 387 | v = bytestream2_get_byteu(&s->gb); |
| 388 | s->color_resolution = ((v & 0x70) >> 4) + 1; |
| 389 | s->has_global_palette = (v & 0x80); |
| 390 | s->bits_per_pixel = (v & 0x07) + 1; |
| 391 | background_color_index = bytestream2_get_byteu(&s->gb); |
| 392 | n = bytestream2_get_byteu(&s->gb); |
| 393 | if (n) { |
| 394 | s->avctx->sample_aspect_ratio.num = n + 15; |
| 395 | s->avctx->sample_aspect_ratio.den = 64; |
| 396 | } |
| 397 | |
| 398 | av_dlog(s->avctx, "screen_w=%d screen_h=%d bpp=%d global_palette=%d\n", |
| 399 | s->screen_width, s->screen_height, s->bits_per_pixel, |
| 400 | s->has_global_palette); |
| 401 | |
| 402 | if (s->has_global_palette) { |
| 403 | s->background_color_index = background_color_index; |
| 404 | n = 1 << s->bits_per_pixel; |
| 405 | if (bytestream2_get_bytes_left(&s->gb) < n * 3) |
| 406 | return AVERROR_INVALIDDATA; |
| 407 | |
| 408 | gif_read_palette(s, s->global_palette, n); |
| 409 | s->bg_color = s->global_palette[s->background_color_index]; |
| 410 | } else |
| 411 | s->background_color_index = -1; |
| 412 | |
| 413 | return 0; |
| 414 | } |
| 415 | |
| 416 | static int gif_parse_next_image(GifState *s, AVFrame *frame) |
| 417 | { |
| 418 | while (bytestream2_get_bytes_left(&s->gb) > 0) { |
| 419 | int code = bytestream2_get_byte(&s->gb); |
| 420 | int ret; |
| 421 | |
| 422 | av_log(s->avctx, AV_LOG_DEBUG, "code=%02x '%c'\n", code, code); |
| 423 | |
| 424 | switch (code) { |
| 425 | case GIF_IMAGE_SEPARATOR: |
| 426 | return gif_read_image(s, frame); |
| 427 | case GIF_EXTENSION_INTRODUCER: |
| 428 | if ((ret = gif_read_extension(s)) < 0) |
| 429 | return ret; |
| 430 | break; |
| 431 | case GIF_TRAILER: |
| 432 | /* end of image */ |
| 433 | return AVERROR_EOF; |
| 434 | default: |
| 435 | /* erroneous block label */ |
| 436 | return AVERROR_INVALIDDATA; |
| 437 | } |
| 438 | } |
| 439 | return AVERROR_EOF; |
| 440 | } |
| 441 | |
| 442 | static av_cold int gif_decode_init(AVCodecContext *avctx) |
| 443 | { |
| 444 | GifState *s = avctx->priv_data; |
| 445 | |
| 446 | s->avctx = avctx; |
| 447 | |
| 448 | avctx->pix_fmt = AV_PIX_FMT_RGB32; |
| 449 | s->frame = av_frame_alloc(); |
| 450 | if (!s->frame) |
| 451 | return AVERROR(ENOMEM); |
| 452 | ff_lzw_decode_open(&s->lzw); |
| 453 | return 0; |
| 454 | } |
| 455 | |
| 456 | static int gif_decode_frame(AVCodecContext *avctx, void *data, int *got_frame, AVPacket *avpkt) |
| 457 | { |
| 458 | GifState *s = avctx->priv_data; |
| 459 | int ret; |
| 460 | |
| 461 | bytestream2_init(&s->gb, avpkt->data, avpkt->size); |
| 462 | |
| 463 | s->frame->pts = avpkt->pts; |
| 464 | s->frame->pkt_pts = avpkt->pts; |
| 465 | s->frame->pkt_dts = avpkt->dts; |
| 466 | av_frame_set_pkt_duration(s->frame, avpkt->duration); |
| 467 | |
| 468 | if (avpkt->size >= 6) { |
| 469 | s->keyframe = memcmp(avpkt->data, gif87a_sig, 6) == 0 || |
| 470 | memcmp(avpkt->data, gif89a_sig, 6) == 0; |
| 471 | } else { |
| 472 | s->keyframe = 0; |
| 473 | } |
| 474 | |
| 475 | if (s->keyframe) { |
| 476 | s->keyframe_ok = 0; |
| 477 | s->gce_prev_disposal = GCE_DISPOSAL_NONE; |
| 478 | if ((ret = gif_read_header1(s)) < 0) |
| 479 | return ret; |
| 480 | |
| 481 | if ((ret = ff_set_dimensions(avctx, s->screen_width, s->screen_height)) < 0) |
| 482 | return ret; |
| 483 | |
| 484 | av_frame_unref(s->frame); |
| 485 | if ((ret = ff_get_buffer(avctx, s->frame, 0)) < 0) |
| 486 | return ret; |
| 487 | |
| 488 | av_fast_malloc(&s->idx_line, &s->idx_line_size, s->screen_width); |
| 489 | if (!s->idx_line) |
| 490 | return AVERROR(ENOMEM); |
| 491 | |
| 492 | s->frame->pict_type = AV_PICTURE_TYPE_I; |
| 493 | s->frame->key_frame = 1; |
| 494 | s->keyframe_ok = 1; |
| 495 | } else { |
| 496 | if (!s->keyframe_ok) { |
| 497 | av_log(avctx, AV_LOG_ERROR, "cannot decode frame without keyframe\n"); |
| 498 | return AVERROR_INVALIDDATA; |
| 499 | } |
| 500 | |
| 501 | if ((ret = ff_reget_buffer(avctx, s->frame)) < 0) |
| 502 | return ret; |
| 503 | |
| 504 | s->frame->pict_type = AV_PICTURE_TYPE_P; |
| 505 | s->frame->key_frame = 0; |
| 506 | } |
| 507 | |
| 508 | ret = gif_parse_next_image(s, s->frame); |
| 509 | if (ret < 0) |
| 510 | return ret; |
| 511 | |
| 512 | if ((ret = av_frame_ref(data, s->frame)) < 0) |
| 513 | return ret; |
| 514 | *got_frame = 1; |
| 515 | |
| 516 | return bytestream2_tell(&s->gb); |
| 517 | } |
| 518 | |
| 519 | static av_cold int gif_decode_close(AVCodecContext *avctx) |
| 520 | { |
| 521 | GifState *s = avctx->priv_data; |
| 522 | |
| 523 | ff_lzw_decode_close(&s->lzw); |
| 524 | av_frame_free(&s->frame); |
| 525 | av_freep(&s->idx_line); |
| 526 | av_freep(&s->stored_img); |
| 527 | |
| 528 | return 0; |
| 529 | } |
| 530 | |
| 531 | static const AVOption options[] = { |
| 532 | { "trans_color", "color value (ARGB) that is used instead of transparent color", |
| 533 | offsetof(GifState, trans_color), AV_OPT_TYPE_INT, |
| 534 | {.i64 = GIF_TRANSPARENT_COLOR}, 0, 0xffffffff, |
| 535 | AV_OPT_FLAG_DECODING_PARAM|AV_OPT_FLAG_VIDEO_PARAM }, |
| 536 | { NULL }, |
| 537 | }; |
| 538 | |
| 539 | static const AVClass decoder_class = { |
| 540 | .class_name = "gif decoder", |
| 541 | .item_name = av_default_item_name, |
| 542 | .option = options, |
| 543 | .version = LIBAVUTIL_VERSION_INT, |
| 544 | .category = AV_CLASS_CATEGORY_DECODER, |
| 545 | }; |
| 546 | |
| 547 | AVCodec ff_gif_decoder = { |
| 548 | .name = "gif", |
| 549 | .long_name = NULL_IF_CONFIG_SMALL("GIF (Graphics Interchange Format)"), |
| 550 | .type = AVMEDIA_TYPE_VIDEO, |
| 551 | .id = AV_CODEC_ID_GIF, |
| 552 | .priv_data_size = sizeof(GifState), |
| 553 | .init = gif_decode_init, |
| 554 | .close = gif_decode_close, |
| 555 | .decode = gif_decode_frame, |
| 556 | .capabilities = CODEC_CAP_DR1, |
| 557 | .priv_class = &decoder_class, |
| 558 | }; |