LCOV - code coverage report
Current view: directory - gfx/cairo/cairo/src - cairo-image-info.c (source / functions) Found Hit Coverage
Test: app.info Lines: 92 0 0.0 %
Date: 2012-06-02 Functions: 11 0 0.0 %

       1                 : /* cairo - a vector graphics library with display and print output
       2                 :  *
       3                 :  * Copyright © 2008 Adrian Johnson
       4                 :  *
       5                 :  * This library is free software; you can redistribute it and/or
       6                 :  * modify it either under the terms of the GNU Lesser General Public
       7                 :  * License version 2.1 as published by the Free Software Foundation
       8                 :  * (the "LGPL") or, at your option, under the terms of the Mozilla
       9                 :  * Public License Version 1.1 (the "MPL"). If you do not alter this
      10                 :  * notice, a recipient may use your version of this file under either
      11                 :  * the MPL or the LGPL.
      12                 :  *
      13                 :  * You should have received a copy of the LGPL along with this library
      14                 :  * in the file COPYING-LGPL-2.1; if not, write to the Free Software
      15                 :  * Foundation, Inc., 51 Franklin Street, Suite 500, Boston, MA 02110-1335, USA
      16                 :  * You should have received a copy of the MPL along with this library
      17                 :  * in the file COPYING-MPL-1.1
      18                 :  *
      19                 :  * The contents of this file are subject to the Mozilla Public License
      20                 :  * Version 1.1 (the "License"); you may not use this file except in
      21                 :  * compliance with the License. You may obtain a copy of the License at
      22                 :  * http://www.mozilla.org/MPL/
      23                 :  *
      24                 :  * This software is distributed on an "AS IS" basis, WITHOUT WARRANTY
      25                 :  * OF ANY KIND, either express or implied. See the LGPL or the MPL for
      26                 :  * the specific language governing rights and limitations.
      27                 :  *
      28                 :  * The Original Code is the cairo graphics library.
      29                 :  *
      30                 :  * The Initial Developer of the Original Code is Adrian Johnson.
      31                 :  *
      32                 :  * Contributor(s):
      33                 :  *      Adrian Johnson <ajohnson@redneon.com>
      34                 :  */
      35                 : 
      36                 : #include "cairoint.h"
      37                 : #include "cairo-image-info-private.h"
      38                 : 
      39                 : static uint32_t
      40               0 : _get_be32 (const unsigned char *p)
      41                 : {
      42               0 :     return p[0] << 24 | p[1] << 16 | p[2] << 8 | p[3];
      43                 : }
      44                 : 
      45                 : /* JPEG (image/jpeg)
      46                 :  *
      47                 :  * http://www.w3.org/Graphics/JPEG/itu-t81.pdf
      48                 :  */
      49                 : 
      50                 : /* Markers with no parameters. All other markers are followed by a two
      51                 :  * byte length of the parameters. */
      52                 : #define TEM       0x01
      53                 : #define RST_begin 0xd0
      54                 : #define RST_end   0xd7
      55                 : #define SOI       0xd8
      56                 : #define EOI       0xd9
      57                 : 
      58                 : /* Start of frame markers. */
      59                 : #define SOF0  0xc0
      60                 : #define SOF1  0xc1
      61                 : #define SOF2  0xc2
      62                 : #define SOF3  0xc3
      63                 : #define SOF5  0xc5
      64                 : #define SOF6  0xc6
      65                 : #define SOF7  0xc7
      66                 : #define SOF9  0xc9
      67                 : #define SOF10 0xca
      68                 : #define SOF11 0xcb
      69                 : #define SOF13 0xcd
      70                 : #define SOF14 0xce
      71                 : #define SOF15 0xcf
      72                 : 
      73                 : static const unsigned char *
      74               0 : _jpeg_skip_segment (const unsigned char *p)
      75                 : {
      76                 :     int len;
      77                 : 
      78               0 :     p++;
      79               0 :     len = (p[0] << 8) | p[1];
      80                 : 
      81               0 :     return p + len;
      82                 : }
      83                 : 
      84                 : static void
      85               0 : _jpeg_extract_info (cairo_image_info_t *info, const unsigned char *p)
      86                 : {
      87               0 :     info->width = (p[6] << 8) + p[7];
      88               0 :     info->height = (p[4] << 8) + p[5];
      89               0 :     info->num_components = p[8];
      90               0 :     info->bits_per_component = p[3];
      91               0 : }
      92                 : 
      93                 : cairo_int_status_t
      94               0 : _cairo_image_info_get_jpeg_info (cairo_image_info_t     *info,
      95                 :                                  const unsigned char    *data,
      96                 :                                  long                    length)
      97                 : {
      98               0 :     const unsigned char *p = data;
      99                 : 
     100               0 :     while (p + 1 < data + length) {
     101               0 :         if (*p != 0xff)
     102               0 :             return CAIRO_INT_STATUS_UNSUPPORTED;
     103               0 :         p++;
     104                 : 
     105               0 :         switch (*p) {
     106                 :             /* skip fill bytes */
     107                 :         case 0xff:
     108               0 :             p++;
     109               0 :             break;
     110                 : 
     111                 :         case TEM:
     112                 :         case SOI:
     113                 :         case EOI:
     114               0 :             p++;
     115               0 :             break;
     116                 : 
     117                 :         case SOF0:
     118                 :         case SOF1:
     119                 :         case SOF2:
     120                 :         case SOF3:
     121                 :         case SOF5:
     122                 :         case SOF6:
     123                 :         case SOF7:
     124                 :         case SOF9:
     125                 :         case SOF10:
     126                 :         case SOF11:
     127                 :         case SOF13:
     128                 :         case SOF14:
     129                 :         case SOF15:
     130                 :             /* Start of frame found. Extract the image parameters. */
     131               0 :             if (p + 8 > data + length)
     132               0 :                 return CAIRO_INT_STATUS_UNSUPPORTED;
     133                 : 
     134               0 :             _jpeg_extract_info (info, p);
     135               0 :             return CAIRO_STATUS_SUCCESS;
     136                 : 
     137                 :         default:
     138               0 :             if (*p >= RST_begin && *p <= RST_end) {
     139               0 :                 p++;
     140               0 :                 break;
     141                 :             }
     142                 : 
     143               0 :             if (p + 2 > data + length)
     144               0 :                 return CAIRO_INT_STATUS_UNSUPPORTED;
     145                 : 
     146               0 :             p = _jpeg_skip_segment (p);
     147               0 :             break;
     148                 :         }
     149                 :     }
     150                 : 
     151               0 :     return CAIRO_STATUS_SUCCESS;
     152                 : }
     153                 : 
     154                 : /* JPEG 2000 (image/jp2)
     155                 :  *
     156                 :  * http://www.jpeg.org/public/15444-1annexi.pdf
     157                 :  */
     158                 : 
     159                 : #define JPX_FILETYPE 0x66747970
     160                 : #define JPX_JP2_HEADER 0x6A703268
     161                 : #define JPX_IMAGE_HEADER 0x69686472
     162                 : 
     163                 : static const unsigned char _jpx_signature[] = {
     164                 :     0x00, 0x00, 0x00, 0x0c, 0x6a, 0x50, 0x20, 0x20, 0x0d, 0x0a, 0x87, 0x0a
     165                 : };
     166                 : 
     167                 : static const unsigned char *
     168               0 : _jpx_next_box (const unsigned char *p)
     169                 : {
     170               0 :     return p + _get_be32 (p);
     171                 : }
     172                 : 
     173                 : static const unsigned char *
     174               0 : _jpx_get_box_contents (const unsigned char *p)
     175                 : {
     176               0 :     return p + 8;
     177                 : }
     178                 : 
     179                 : static cairo_bool_t
     180               0 : _jpx_match_box (const unsigned char *p, const unsigned char *end, uint32_t type)
     181                 : {
     182                 :     uint32_t length;
     183                 : 
     184               0 :     if (p + 8 < end) {
     185               0 :         length = _get_be32 (p);
     186               0 :         if (_get_be32 (p + 4) == type &&  p + length < end)
     187               0 :             return TRUE;
     188                 :     }
     189                 : 
     190               0 :     return FALSE;
     191                 : }
     192                 : 
     193                 : static const unsigned char *
     194               0 : _jpx_find_box (const unsigned char *p, const unsigned char *end, uint32_t type)
     195                 : {
     196               0 :     while (p < end) {
     197               0 :         if (_jpx_match_box (p, end, type))
     198               0 :             return p;
     199               0 :         p = _jpx_next_box (p);
     200                 :     }
     201                 : 
     202               0 :     return NULL;
     203                 : }
     204                 : 
     205                 : static void
     206               0 : _jpx_extract_info (const unsigned char *p, cairo_image_info_t *info)
     207                 : {
     208               0 :     info->height = _get_be32 (p);
     209               0 :     info->width = _get_be32 (p + 4);
     210               0 :     info->num_components = (p[8] << 8) + p[9];
     211               0 :     info->bits_per_component = p[10];
     212               0 : }
     213                 : 
     214                 : cairo_int_status_t
     215               0 : _cairo_image_info_get_jpx_info (cairo_image_info_t      *info,
     216                 :                                 const unsigned char     *data,
     217                 :                                 unsigned long            length)
     218                 : {
     219               0 :     const unsigned char *p = data;
     220               0 :     const unsigned char *end = data + length;
     221                 : 
     222                 :     /* First 12 bytes must be the JPEG 2000 signature box. */
     223               0 :     if (length < ARRAY_LENGTH(_jpx_signature) ||
     224               0 :         memcmp(p, _jpx_signature, ARRAY_LENGTH(_jpx_signature)) != 0)
     225               0 :         return CAIRO_INT_STATUS_UNSUPPORTED;
     226                 : 
     227               0 :     p += ARRAY_LENGTH(_jpx_signature);
     228                 : 
     229                 :     /* Next box must be a File Type Box */
     230               0 :     if (! _jpx_match_box (p, end, JPX_FILETYPE))
     231               0 :         return CAIRO_INT_STATUS_UNSUPPORTED;
     232                 : 
     233               0 :     p = _jpx_next_box (p);
     234                 : 
     235                 :     /* Locate the JP2 header box. */
     236               0 :     p = _jpx_find_box (p, end, JPX_JP2_HEADER);
     237               0 :     if (!p)
     238               0 :         return CAIRO_INT_STATUS_UNSUPPORTED;
     239                 : 
     240                 :     /* Step into the JP2 header box. First box must be the Image
     241                 :      * Header */
     242               0 :     p = _jpx_get_box_contents (p);
     243               0 :     if (! _jpx_match_box (p, end, JPX_IMAGE_HEADER))
     244               0 :         return CAIRO_INT_STATUS_UNSUPPORTED;
     245                 : 
     246                 :     /* Get the image info */
     247               0 :     p = _jpx_get_box_contents (p);
     248               0 :     _jpx_extract_info (p, info);
     249                 : 
     250               0 :     return CAIRO_STATUS_SUCCESS;
     251                 : }
     252                 : 
     253                 : /* PNG (image/png)
     254                 :  *
     255                 :  * http://www.w3.org/TR/2003/REC-PNG-20031110/
     256                 :  */
     257                 : 
     258                 : #define PNG_IHDR 0x49484452
     259                 : 
     260                 : static const unsigned char _png_magic[8] = { 137, 80, 78, 71, 13, 10, 26, 10 };
     261                 : 
     262                 : cairo_int_status_t
     263               0 : _cairo_image_info_get_png_info (cairo_image_info_t     *info,
     264                 :                                const unsigned char     *data,
     265                 :                                unsigned long            length)
     266                 : {
     267               0 :     const unsigned char *p = data;
     268               0 :     const unsigned char *end = data + length;
     269                 : 
     270               0 :     if (length < 8 || memcmp (data, _png_magic, 8) != 0)
     271               0 :        return CAIRO_INT_STATUS_UNSUPPORTED;
     272                 : 
     273               0 :     p += 8;
     274                 : 
     275                 :     /* The first chunk must be IDHR. IDHR has 13 bytes of data plus
     276                 :      * the 12 bytes of overhead for the chunk. */
     277               0 :     if (p + 13 + 12 > end)
     278               0 :        return CAIRO_INT_STATUS_UNSUPPORTED;
     279                 : 
     280               0 :     p += 4;
     281               0 :     if (_get_be32 (p) != PNG_IHDR)
     282               0 :        return CAIRO_INT_STATUS_UNSUPPORTED;
     283                 : 
     284               0 :     p += 4;
     285               0 :     info->width = _get_be32 (p);
     286               0 :     p += 4;
     287               0 :     info->height = _get_be32 (p);
     288                 : 
     289               0 :     return CAIRO_STATUS_SUCCESS;
     290                 : }

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