ffmpeg/libavcodec/targa.c

   1 /*
   2  * Targa (.tga) image 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 #include "libavutil/intreadwrite.h"
  23 #include "libavutil/imgutils.h"
  24 #include "avcodec.h"
  25 #include "bytestream.h"
  26 #include "internal.h"
  27 #include "targa.h"
  28
  29 typedef struct TargaContext {
  30     GetByteContext gb;
  31 } TargaContext;
  32
  33 static uint8_t *advance_line(uint8_t *start, uint8_t *line,
  34                              int stride, int *y, int h, int interleave)
  35 {
  36     *y += interleave;
  37
  38     if (*y < h) {
  39         return line + interleave * stride;
  40     } else {
  41         *y = (*y + 1) & (interleave - 1);
  42         if (*y && *y < h) {
  43             return start + *y * stride;
  44         } else {
  45             return NULL;
  46         }
  47     }
  48 }
  49
  50 static int targa_decode_rle(AVCodecContext *avctx, TargaContext *s,
  51                             uint8_t *start, int w, int h, int stride,
  52                             int bpp, int interleave)
  53 {
  54     int x, y;
  55     int depth = (bpp + 1) >> 3;
  56     int type, count;
  57     uint8_t *line = start;
  58     uint8_t *dst  = line;
  59
  60     x = y = count = 0;
  61     while (dst) {
  62         if (bytestream2_get_bytes_left(&s->gb) <= 0) {
  63             av_log(avctx, AV_LOG_ERROR,
  64                    "Ran ouf of data before end-of-image\n");
  65             return AVERROR_INVALIDDATA;
  66         }
  67         type  = bytestream2_get_byteu(&s->gb);
  68         count = (type & 0x7F) + 1;
  69         type &= 0x80;
  70         if (!type) {
  71             do {
  72                 int n  = FFMIN(count, w - x);
  73                 bytestream2_get_buffer(&s->gb, dst, n * depth);
  74                 count -= n;
  75                 dst   += n * depth;
  76                 x     += n;
  77                 if (x == w) {
  78                     x    = 0;
  79                     dst = line = advance_line(start, line, stride, &y, h, interleave);
  80                 }
  81             } while (dst && count > 0);
  82         } else {
  83             uint8_t tmp[4];
  84             bytestream2_get_buffer(&s->gb, tmp, depth);
  85             do {
  86                 int n  = FFMIN(count, w - x);
  87                 count -= n;
  88                 x     += n;
  89                 do {
  90                     memcpy(dst, tmp, depth);
  91                     dst += depth;
  92                 } while (--n);
  93                 if (x == w) {
  94                     x    = 0;
  95                     dst = line = advance_line(start, line, stride, &y, h, interleave);
  96                 }
  97             } while (dst && count > 0);
  98         }
  99     }
 100
 101     if (count) {
 102         av_log(avctx, AV_LOG_ERROR, "Packet went out of bounds\n");
 103         return AVERROR_INVALIDDATA;
 104     }
 105
 106     return 0;
 107 }
 108
 109 static int decode_frame(AVCodecContext *avctx,
 110                         void *data, int *got_frame,
 111                         AVPacket *avpkt)
 112 {
 113     TargaContext * const s = avctx->priv_data;
 114     AVFrame * const p = data;
 115     uint8_t *dst;
 116     int stride;
 117     int idlen, pal, compr, y, w, h, bpp, flags, ret;
 118     int first_clr, colors, csize;
 119     int interleave;
 120
 121     bytestream2_init(&s->gb, avpkt->data, avpkt->size);
 122
 123     /* parse image header */
 124     idlen     = bytestream2_get_byte(&s->gb);
 125     pal       = bytestream2_get_byte(&s->gb);
 126     compr     = bytestream2_get_byte(&s->gb);
 127     first_clr = bytestream2_get_le16(&s->gb);
 128     colors    = bytestream2_get_le16(&s->gb);
 129     csize     = bytestream2_get_byte(&s->gb);
 130     bytestream2_skip(&s->gb, 4); /* 2: x, 2: y */
 131     w         = bytestream2_get_le16(&s->gb);
 132     h         = bytestream2_get_le16(&s->gb);
 133     bpp       = bytestream2_get_byte(&s->gb);
 134
 135     if (bytestream2_get_bytes_left(&s->gb) <= idlen) {
 136         av_log(avctx, AV_LOG_ERROR,
 137                 "Not enough data to read header\n");
 138         return AVERROR_INVALIDDATA;
 139     }
 140
 141     flags     = bytestream2_get_byte(&s->gb);
 142
 143     if (!pal && (first_clr || colors || csize)) {
 144         av_log(avctx, AV_LOG_WARNING, "File without colormap has colormap information set.\n");
 145         // specification says we should ignore those value in this case
 146         first_clr = colors = csize = 0;
 147     }
 148
 149     // skip identifier if any
 150     bytestream2_skip(&s->gb, idlen);
 151
 152     switch (bpp) {
 153     case 8:
 154         avctx->pix_fmt = ((compr & (~TGA_RLE)) == TGA_BW) ? AV_PIX_FMT_GRAY8 : AV_PIX_FMT_PAL8;
 155         break;
 156     case 15:
 157     case 16:
 158         avctx->pix_fmt = AV_PIX_FMT_RGB555LE;
 159         break;
 160     case 24:
 161         avctx->pix_fmt = AV_PIX_FMT_BGR24;
 162         break;
 163     case 32:
 164         avctx->pix_fmt = AV_PIX_FMT_BGRA;
 165         break;
 166     default:
 167         av_log(avctx, AV_LOG_ERROR, "Bit depth %i is not supported\n", bpp);
 168         return AVERROR_INVALIDDATA;
 169     }
 170
 171     if (colors && (colors + first_clr) > 256) {
 172         av_log(avctx, AV_LOG_ERROR, "Incorrect palette: %i colors with offset %i\n", colors, first_clr);
 173         return AVERROR_INVALIDDATA;
 174     }
 175
 176     if ((ret = ff_set_dimensions(avctx, w, h)) < 0)
 177         return ret;
 178
 179     if ((ret = ff_get_buffer(avctx, p, 0)) < 0)
 180         return ret;
 181     p->pict_type = AV_PICTURE_TYPE_I;
 182
 183     if (flags & TGA_TOPTOBOTTOM) {
 184         dst = p->data[0];
 185         stride = p->linesize[0];
 186     } else { //image is upside-down
 187         dst = p->data[0] + p->linesize[0] * (h - 1);
 188         stride = -p->linesize[0];
 189     }
 190
 191     interleave = flags & TGA_INTERLEAVE2 ? 2 :
 192                  flags & TGA_INTERLEAVE4 ? 4 : 1;
 193
 194     if (colors) {
 195         int pal_size, pal_sample_size;
 196
 197         switch (csize) {
 198         case 32: pal_sample_size = 4; break;
 199         case 24: pal_sample_size = 3; break;
 200         case 16:
 201         case 15: pal_sample_size = 2; break;
 202         default:
 203             av_log(avctx, AV_LOG_ERROR, "Palette entry size %i bits is not supported\n", csize);
 204             return AVERROR_INVALIDDATA;
 205         }
 206         pal_size = colors * pal_sample_size;
 207         if (avctx->pix_fmt != AV_PIX_FMT_PAL8) //should not occur but skip palette anyway
 208             bytestream2_skip(&s->gb, pal_size);
 209         else {
 210             int t;
 211             uint32_t *pal = ((uint32_t *)p->data[1]) + first_clr;
 212
 213             if (bytestream2_get_bytes_left(&s->gb) < pal_size) {
 214                 av_log(avctx, AV_LOG_ERROR,
 215                        "Not enough data to read palette\n");
 216                 return AVERROR_INVALIDDATA;
 217             }
 218             switch (pal_sample_size) {
 219             case 4:
 220                 for (t = 0; t < colors; t++)
 221                     *pal++ = bytestream2_get_le32u(&s->gb);
 222                 break;
 223             case 3:
 224                 /* RGB24 */
 225                 for (t = 0; t < colors; t++)
 226                     *pal++ = (0xffU<<24) | bytestream2_get_le24u(&s->gb);
 227                 break;
 228             case 2:
 229                 /* RGB555 */
 230                 for (t = 0; t < colors; t++) {
 231                     uint32_t v = bytestream2_get_le16u(&s->gb);
 232                     v = ((v & 0x7C00) <<  9) |
 233                         ((v & 0x03E0) <<  6) |
 234                         ((v & 0x001F) <<  3);
 235                     /* left bit replication */
 236                     v |= (v & 0xE0E0E0U) >> 5;
 237                     *pal++ = (0xffU<<24) | v;
 238                 }
 239                 break;
 240             }
 241             p->palette_has_changed = 1;
 242         }
 243     }
 244
 245     if ((compr & (~TGA_RLE)) == TGA_NODATA) {
 246         memset(p->data[0], 0, p->linesize[0] * h);
 247     } else {
 248         if (compr & TGA_RLE) {
 249             int res = targa_decode_rle(avctx, s, dst, w, h, stride, bpp, interleave);
 250             if (res < 0)
 251                 return res;
 252         } else {
 253             size_t img_size = w * ((bpp + 1) >> 3);
 254             uint8_t *line;
 255             if (bytestream2_get_bytes_left(&s->gb) < img_size * h) {
 256                 av_log(avctx, AV_LOG_ERROR,
 257                        "Not enough data available for image\n");
 258                 return AVERROR_INVALIDDATA;
 259             }
 260
 261             line = dst;
 262             y = 0;
 263             do {
 264                 bytestream2_get_buffer(&s->gb, line, img_size);
 265                 line = advance_line(dst, line, stride, &y, h, interleave);
 266             } while (line);
 267         }
 268     }
 269
 270     if (flags & TGA_RIGHTTOLEFT) { // right-to-left, needs horizontal flip
 271         int x;
 272         for (y = 0; y < h; y++) {
 273             void *line = &p->data[0][y * p->linesize[0]];
 274             for (x = 0; x < w >> 1; x++) {
 275                 switch (bpp) {
 276                 case 32:
 277                     FFSWAP(uint32_t, ((uint32_t *)line)[x], ((uint32_t *)line)[w - x - 1]);
 278                     break;
 279                 case 24:
 280                     FFSWAP(uint8_t, ((uint8_t *)line)[3 * x    ], ((uint8_t *)line)[3 * w - 3 * x - 3]);
 281                     FFSWAP(uint8_t, ((uint8_t *)line)[3 * x + 1], ((uint8_t *)line)[3 * w - 3 * x - 2]);
 282                     FFSWAP(uint8_t, ((uint8_t *)line)[3 * x + 2], ((uint8_t *)line)[3 * w - 3 * x - 1]);
 283                     break;
 284                 case 16:
 285                     FFSWAP(uint16_t, ((uint16_t *)line)[x], ((uint16_t *)line)[w - x - 1]);
 286                     break;
 287                 case 8:
 288                     FFSWAP(uint8_t, ((uint8_t *)line)[x], ((uint8_t *)line)[w - x - 1]);
 289                 }
 290             }
 291         }
 292     }
 293
 294     *got_frame = 1;
 295
 296     return avpkt->size;
 297 }
 298
 299 AVCodec ff_targa_decoder = {
 300     .name           = "targa",
 301     .long_name      = NULL_IF_CONFIG_SMALL("Truevision Targa image"),
 302     .type           = AVMEDIA_TYPE_VIDEO,
 303     .id             = AV_CODEC_ID_TARGA,
 304     .priv_data_size = sizeof(TargaContext),
 305     .decode         = decode_frame,
 306     .capabilities   = CODEC_CAP_DR1,
 307 };