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 #include "avcodec.h"
  22
  23 enum TargaCompr{
  24     TGA_NODATA = 0, // no image data
  25     TGA_PAL    = 1, // palettized
  26     TGA_RGB    = 2, // true-color
  27     TGA_BW     = 3, // black & white or grayscale
  28     TGA_RLE    = 8, // flag pointing that data is RLE-coded
  29 };
  30
  31 typedef struct TargaContext {
  32     AVFrame picture;
  33
  34     int width, height;
  35     int bpp;
  36     int color_type;
  37     int compression_type;
  38 } TargaContext;
  39
  40 static void targa_decode_rle(AVCodecContext *avctx, TargaContext *s, const uint8_t *src, uint8_t *dst, int w, int h, int stride, int bpp)
  41 {
  42     int i, x, y;
  43     int depth = (bpp + 1) >> 3;
  44     int type, count;
  45     int diff;
  46
  47     diff = stride - w * depth;
  48     x = y = 0;
  49     while(y < h){
  50         type = *src++;
  51         count = (type & 0x7F) + 1;
  52         type &= 0x80;
  53         if((x + count > w) && (x + count + 1 > (h - y) * w)){
  54             av_log(avctx, AV_LOG_ERROR, "Packet went out of bounds: position (%i,%i) size %i\n", x, y, count);
  55             return;
  56         }
  57         for(i = 0; i < count; i++){
  58             switch(depth){
  59             case 1:
  60                 *dst = *src;
  61                 break;
  62             case 2:
  63                 *((uint16_t*)dst) = AV_RL16(src);
  64                 break;
  65             case 3:
  66                 dst[0] = src[0];
  67                 dst[1] = src[1];
  68                 dst[2] = src[2];
  69                 break;
  70             case 4:
  71                 *((uint32_t*)dst) = AV_RL32(src);
  72                 break;
  73             }
  74             dst += depth;
  75             if(!type)
  76                 src += depth;
  77
  78             x++;
  79             if(x == w){
  80                 x = 0;
  81                 y++;
  82                 dst += diff;
  83             }
  84         }
  85         if(type)
  86             src += depth;
  87     }
  88 }
  89
  90 static int decode_frame(AVCodecContext *avctx,
  91                         void *data, int *data_size,
  92                         const uint8_t *buf, int buf_size)
  93 {
  94     TargaContext * const s = avctx->priv_data;
  95     AVFrame *picture = data;
  96     AVFrame * const p= (AVFrame*)&s->picture;
  97     uint8_t *dst;
  98     int stride;
  99     int idlen, pal, compr, x, y, w, h, bpp, flags;
 100     int first_clr, colors, csize;
 101
 102     /* parse image header */
 103     idlen = *buf++;
 104     pal = *buf++;
 105     compr = *buf++;
 106     first_clr = AV_RL16(buf); buf += 2;
 107     colors = AV_RL16(buf); buf += 2;
 108     csize = *buf++;
 109     x = AV_RL16(buf); buf += 2;
 110     y = AV_RL16(buf); buf += 2;
 111     w = AV_RL16(buf); buf += 2;
 112     h = AV_RL16(buf); buf += 2;
 113     bpp = *buf++;
 114     flags = *buf++;
 115     //skip identifier if any
 116     buf += idlen;
 117     s->bpp = bpp;
 118     s->width = w;
 119     s->height = h;
 120     switch(s->bpp){
 121     case 8:
 122         avctx->pix_fmt = ((compr & (~TGA_RLE)) == TGA_BW) ? PIX_FMT_GRAY8 : PIX_FMT_PAL8;
 123         break;
 124     case 15:
 125         avctx->pix_fmt = PIX_FMT_RGB555;
 126         break;
 127     case 16:
 128         avctx->pix_fmt = PIX_FMT_RGB555;
 129         break;
 130     case 24:
 131         avctx->pix_fmt = PIX_FMT_BGR24;
 132         break;
 133     case 32:
 134         avctx->pix_fmt = PIX_FMT_RGB32;
 135         break;
 136     default:
 137         av_log(avctx, AV_LOG_ERROR, "Bit depth %i is not supported\n", s->bpp);
 138         return -1;
 139     }
 140
 141     if(s->picture.data[0])
 142         avctx->release_buffer(avctx, &s->picture);
 143
 144     if(avcodec_check_dimensions(avctx, w, h))
 145         return -1;
 146     if(w != avctx->width || h != avctx->height)
 147         avcodec_set_dimensions(avctx, w, h);
 148     if(avctx->get_buffer(avctx, p) < 0){
 149         av_log(avctx, AV_LOG_ERROR, "get_buffer() failed\n");
 150         return -1;
 151     }
 152     if(flags & 0x20){
 153         dst = p->data[0];
 154         stride = p->linesize[0];
 155     }else{ //image is upside-down
 156         dst = p->data[0] + p->linesize[0] * (h - 1);
 157         stride = -p->linesize[0];
 158     }
 159
 160     if(avctx->pix_fmt == PIX_FMT_PAL8 && avctx->palctrl){
 161         memcpy(p->data[1], avctx->palctrl->palette, AVPALETTE_SIZE);
 162         if(avctx->palctrl->palette_changed){
 163             p->palette_has_changed = 1;
 164             avctx->palctrl->palette_changed = 0;
 165         }
 166     }
 167     if(colors){
 168         if((colors + first_clr) > 256){
 169             av_log(avctx, AV_LOG_ERROR, "Incorrect palette: %i colors with offset %i\n", colors, first_clr);
 170             return -1;
 171         }
 172         if(csize != 24){
 173             av_log(avctx, AV_LOG_ERROR, "Palette entry size %i bits is not supported\n", csize);
 174             return -1;
 175         }
 176         if(avctx->pix_fmt != PIX_FMT_PAL8)//should not occur but skip palette anyway
 177             buf += colors * ((csize + 1) >> 3);
 178         else{
 179             int r, g, b, t;
 180             int32_t *pal = ((int32_t*)p->data[1]) + first_clr;
 181             for(t = 0; t < colors; t++){
 182                 r = *buf++;
 183                 g = *buf++;
 184                 b = *buf++;
 185                 *pal++ = (b << 16) | (g << 8) | r;
 186             }
 187             p->palette_has_changed = 1;
 188             avctx->palctrl->palette_changed = 0;
 189         }
 190     }
 191     if((compr & (~TGA_RLE)) == TGA_NODATA)
 192         memset(p->data[0], 0, p->linesize[0] * s->height);
 193     else{
 194         if(compr & TGA_RLE)
 195             targa_decode_rle(avctx, s, buf, dst, avctx->width, avctx->height, stride, bpp);
 196         else{
 197             for(y = 0; y < s->height; y++){
 198 #ifdef WORDS_BIGENDIAN
 199                 if((s->bpp + 1) >> 3 == 2){
 200                     uint16_t *dst16 = (uint16_t*)dst;
 201                     for(x = 0; x < s->width; x++)
 202                         dst16[x] = AV_RL16(buf + x * 2);
 203                 }else if((s->bpp + 1) >> 3 == 4){
 204                     uint32_t *dst32 = (uint32_t*)dst;
 205                     for(x = 0; x < s->width; x++)
 206                         dst32[x] = AV_RL32(buf + x * 4);
 207                 }else
 208 #endif
 209                     memcpy(dst, buf, s->width * ((s->bpp + 1) >> 3));
 210
 211                 dst += stride;
 212                 buf += s->width * ((s->bpp + 1) >> 3);
 213             }
 214         }
 215     }
 216
 217     *picture= *(AVFrame*)&s->picture;
 218     *data_size = sizeof(AVPicture);
 219
 220     return buf_size;
 221 }
 222
 223 static av_cold int targa_init(AVCodecContext *avctx){
 224     TargaContext *s = avctx->priv_data;
 225
 226     avcodec_get_frame_defaults((AVFrame*)&s->picture);
 227     avctx->coded_frame= (AVFrame*)&s->picture;
 228     s->picture.data[0] = NULL;
 229
 230     return 0;
 231 }
 232
 233 static av_cold int targa_end(AVCodecContext *avctx){
 234     TargaContext *s = avctx->priv_data;
 235
 236     if(s->picture.data[0])
 237         avctx->release_buffer(avctx, &s->picture);
 238
 239     return 0;
 240 }
 241
 242 AVCodec targa_decoder = {
 243     "targa",
 244     CODEC_TYPE_VIDEO,
 245     CODEC_ID_TARGA,
 246     sizeof(TargaContext),
 247     targa_init,
 248     NULL,
 249     targa_end,
 250     decode_frame,
 251     0,
 252     NULL,
 253     .long_name = NULL_IF_CONFIG_SMALL("Truevision Targa image"),
 254 };