1/* 2 * Targa (.tga) image decoder 3 * Copyright (c) 2006 Konstantin Shishkov 4 * 5 * This file is part of Libav. 6 * 7 * Libav 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 * Libav 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 Libav; if not, write to the Free Software 19 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA 20 */ 21 22#include "libavutil/intreadwrite.h" 23#include "libavutil/imgutils.h" 24#include "avcodec.h" 25#include "bytestream.h" 26#include "targa.h" 27 28typedef struct TargaContext { 29 AVFrame picture; 30 31 int width, height; 32 int bpp; 33 int color_type; 34 int compression_type; 35} TargaContext; 36 37#define CHECK_BUFFER_SIZE(buf, buf_end, needed, where) \ 38 if(needed > buf_end - buf){ \ 39 av_log(avctx, AV_LOG_ERROR, "Problem: unexpected end of data while reading " where "\n"); \ 40 return -1; \ 41 } \ 42 43static int targa_decode_rle(AVCodecContext *avctx, TargaContext *s, const uint8_t *src, int src_size, uint8_t *dst, int w, int h, int stride, int bpp) 44{ 45 int i, x, y; 46 int depth = (bpp + 1) >> 3; 47 int type, count; 48 int diff; 49 const uint8_t *src_end = src + src_size; 50 51 diff = stride - w * depth; 52 x = y = 0; 53 while(y < h){ 54 CHECK_BUFFER_SIZE(src, src_end, 1, "image type"); 55 type = *src++; 56 count = (type & 0x7F) + 1; 57 type &= 0x80; 58 if((x + count > w) && (x + count + 1 > (h - y) * w)){ 59 av_log(avctx, AV_LOG_ERROR, "Packet went out of bounds: position (%i,%i) size %i\n", x, y, count); 60 return -1; 61 } 62 if(type){ 63 CHECK_BUFFER_SIZE(src, src_end, depth, "image data"); 64 }else{ 65 CHECK_BUFFER_SIZE(src, src_end, count * depth, "image data"); 66 } 67 for(i = 0; i < count; i++){ 68 switch(depth){ 69 case 1: 70 *dst = *src; 71 break; 72 case 2: 73 *((uint16_t*)dst) = AV_RL16(src); 74 break; 75 case 3: 76 dst[0] = src[0]; 77 dst[1] = src[1]; 78 dst[2] = src[2]; 79 break; 80 case 4: 81 *((uint32_t*)dst) = AV_RL32(src); 82 break; 83 } 84 dst += depth; 85 if(!type) 86 src += depth; 87 88 x++; 89 if(x == w){ 90 x = 0; 91 y++; 92 dst += diff; 93 } 94 } 95 if(type) 96 src += depth; 97 } 98 return src_size; 99} 100 101static int decode_frame(AVCodecContext *avctx, 102 void *data, int *data_size, 103 AVPacket *avpkt) 104{ 105 const uint8_t *buf = avpkt->data; 106 const uint8_t *buf_end = avpkt->data + avpkt->size; 107 TargaContext * const s = avctx->priv_data; 108 AVFrame *picture = data; 109 AVFrame * const p= (AVFrame*)&s->picture; 110 uint8_t *dst; 111 int stride; 112 int idlen, compr, y, w, h, bpp, flags; 113 int first_clr, colors, csize; 114 115 /* parse image header */ 116 CHECK_BUFFER_SIZE(buf, buf_end, 18, "header"); 117 idlen = *buf++; 118 buf++; /* pal */ 119 compr = *buf++; 120 first_clr = AV_RL16(buf); buf += 2; 121 colors = AV_RL16(buf); buf += 2; 122 csize = *buf++; 123 buf += 2; /* x */ 124 y = AV_RL16(buf); buf += 2; 125 w = AV_RL16(buf); buf += 2; 126 h = AV_RL16(buf); buf += 2; 127 bpp = *buf++; 128 flags = *buf++; 129 //skip identifier if any 130 CHECK_BUFFER_SIZE(buf, buf_end, idlen, "identifiers"); 131 buf += idlen; 132 s->bpp = bpp; 133 s->width = w; 134 s->height = h; 135 switch(s->bpp){ 136 case 8: 137 avctx->pix_fmt = ((compr & (~TGA_RLE)) == TGA_BW) ? PIX_FMT_GRAY8 : PIX_FMT_PAL8; 138 break; 139 case 15: 140 avctx->pix_fmt = PIX_FMT_RGB555; 141 break; 142 case 16: 143 avctx->pix_fmt = PIX_FMT_RGB555; 144 break; 145 case 24: 146 avctx->pix_fmt = PIX_FMT_BGR24; 147 break; 148 case 32: 149 avctx->pix_fmt = PIX_FMT_RGB32; 150 break; 151 default: 152 av_log(avctx, AV_LOG_ERROR, "Bit depth %i is not supported\n", s->bpp); 153 return -1; 154 } 155 156 if(s->picture.data[0]) 157 avctx->release_buffer(avctx, &s->picture); 158 159 if(av_image_check_size(w, h, 0, avctx)) 160 return -1; 161 if(w != avctx->width || h != avctx->height) 162 avcodec_set_dimensions(avctx, w, h); 163 if(avctx->get_buffer(avctx, p) < 0){ 164 av_log(avctx, AV_LOG_ERROR, "get_buffer() failed\n"); 165 return -1; 166 } 167 if(flags & 0x20){ 168 dst = p->data[0]; 169 stride = p->linesize[0]; 170 }else{ //image is upside-down 171 dst = p->data[0] + p->linesize[0] * (h - 1); 172 stride = -p->linesize[0]; 173 } 174 175 if(colors){ 176 int pal_size, pal_sample_size; 177 if((colors + first_clr) > 256){ 178 av_log(avctx, AV_LOG_ERROR, "Incorrect palette: %i colors with offset %i\n", colors, first_clr); 179 return -1; 180 } 181 switch (csize) { 182 case 24: pal_sample_size = 3; break; 183 case 16: 184 case 15: pal_sample_size = 2; break; 185 default: 186 av_log(avctx, AV_LOG_ERROR, "Palette entry size %i bits is not supported\n", csize); 187 return -1; 188 } 189 pal_size = colors * pal_sample_size; 190 CHECK_BUFFER_SIZE(buf, buf_end, pal_size, "color table"); 191 if(avctx->pix_fmt != PIX_FMT_PAL8)//should not occur but skip palette anyway 192 buf += pal_size; 193 else{ 194 int t; 195 uint32_t *pal = ((uint32_t *)p->data[1]) + first_clr; 196 197 switch (pal_sample_size) { 198 case 3: 199 /* RGB24 */ 200 for (t = 0; t < colors; t++) 201 *pal++ = bytestream_get_le24(&buf); 202 break; 203 case 2: 204 /* RGB555 */ 205 for (t = 0; t < colors; t++) { 206 uint32_t v = bytestream_get_le16(&buf); 207 v = ((v & 0x7C00) << 9) | 208 ((v & 0x03E0) << 6) | 209 ((v & 0x001F) << 3); 210 /* left bit replication */ 211 v |= (v & 0xE0E0E0U) >> 5; 212 *pal++ = v; 213 } 214 break; 215 } 216 p->palette_has_changed = 1; 217 } 218 } 219 if((compr & (~TGA_RLE)) == TGA_NODATA) 220 memset(p->data[0], 0, p->linesize[0] * s->height); 221 else{ 222 if(compr & TGA_RLE){ 223 int res = targa_decode_rle(avctx, s, buf, buf_end - buf, dst, avctx->width, avctx->height, stride, bpp); 224 if (res < 0) 225 return -1; 226 buf += res; 227 }else{ 228 size_t img_size = s->width * ((s->bpp + 1) >> 3); 229 CHECK_BUFFER_SIZE(buf, buf_end, img_size, "image data"); 230 for(y = 0; y < s->height; y++){ 231#if HAVE_BIGENDIAN 232 int x; 233 if((s->bpp + 1) >> 3 == 2){ 234 uint16_t *dst16 = (uint16_t*)dst; 235 for(x = 0; x < s->width; x++) 236 dst16[x] = AV_RL16(buf + x * 2); 237 }else if((s->bpp + 1) >> 3 == 4){ 238 uint32_t *dst32 = (uint32_t*)dst; 239 for(x = 0; x < s->width; x++) 240 dst32[x] = AV_RL32(buf + x * 4); 241 }else 242#endif 243 memcpy(dst, buf, img_size); 244 245 dst += stride; 246 buf += img_size; 247 } 248 } 249 } 250 251 *picture= *(AVFrame*)&s->picture; 252 *data_size = sizeof(AVPicture); 253 254 return avpkt->size; 255} 256 257static av_cold int targa_init(AVCodecContext *avctx){ 258 TargaContext *s = avctx->priv_data; 259 260 avcodec_get_frame_defaults((AVFrame*)&s->picture); 261 avctx->coded_frame= (AVFrame*)&s->picture; 262 263 return 0; 264} 265 266static av_cold int targa_end(AVCodecContext *avctx){ 267 TargaContext *s = avctx->priv_data; 268 269 if(s->picture.data[0]) 270 avctx->release_buffer(avctx, &s->picture); 271 272 return 0; 273} 274 275AVCodec ff_targa_decoder = { 276 .name = "targa", 277 .type = AVMEDIA_TYPE_VIDEO, 278 .id = CODEC_ID_TARGA, 279 .priv_data_size = sizeof(TargaContext), 280 .init = targa_init, 281 .close = targa_end, 282 .decode = decode_frame, 283 .capabilities = CODEC_CAP_DR1, 284 .long_name = NULL_IF_CONFIG_SMALL("Truevision Targa image"), 285}; 286