media/libjpeg/jdicc.c

   1 /*
   2  * jdicc.c
   3  *
   4  * Copyright (C) 1997-1998, Thomas G. Lane, Todd Newman.
   5  * Copyright (C) 2017, D. R. Commander.
   6  * For conditions of distribution and use, see the accompanying README.ijg
   7  * file.
   8  *
   9  * This file provides code to read International Color Consortium (ICC) device
  10  * profiles embedded in JFIF JPEG image files.  The ICC has defined a standard
  11  * for including such data in JPEG "APP2" markers.  The code given here does
  12  * not know anything about the internal structure of the ICC profile data; it
  13  * just knows how to get the profile data from a JPEG file while reading it.
  14  */
  15
  16 #define JPEG_INTERNALS
  17 #include "jinclude.h"
  18 #include "jpeglib.h"
  19 #include "jerror.h"
  20
  21
  22 #define ICC_MARKER  (JPEG_APP0 + 2)     /* JPEG marker code for ICC */
  23 #define ICC_OVERHEAD_LEN  14            /* size of non-profile data in APP2 */
  24
  25
  26 /*
  27  * Handy subroutine to test whether a saved marker is an ICC profile marker.
  28  */
  29
  30 LOCAL(boolean)
  31 marker_is_icc(jpeg_saved_marker_ptr marker)
  32 {
  33   return
  34     marker->marker == ICC_MARKER &&
  35     marker->data_length >= ICC_OVERHEAD_LEN &&
  36     /* verify the identifying string */
  37     marker->data[0] == 0x49 &&
  38     marker->data[1] == 0x43 &&
  39     marker->data[2] == 0x43 &&
  40     marker->data[3] == 0x5F &&
  41     marker->data[4] == 0x50 &&
  42     marker->data[5] == 0x52 &&
  43     marker->data[6] == 0x4F &&
  44     marker->data[7] == 0x46 &&
  45     marker->data[8] == 0x49 &&
  46     marker->data[9] == 0x4C &&
  47     marker->data[10] == 0x45 &&
  48     marker->data[11] == 0x0;
  49 }
  50
  51
  52 /*
  53  * See if there was an ICC profile in the JPEG file being read; if so,
  54  * reassemble and return the profile data.
  55  *
  56  * TRUE is returned if an ICC profile was found, FALSE if not.  If TRUE is
  57  * returned, *icc_data_ptr is set to point to the returned data, and
  58  * *icc_data_len is set to its length.
  59  *
  60  * IMPORTANT: the data at *icc_data_ptr is allocated with malloc() and must be
  61  * freed by the caller with free() when the caller no longer needs it.
  62  * (Alternatively, we could write this routine to use the IJG library's memory
  63  * allocator, so that the data would be freed implicitly when
  64  * jpeg_finish_decompress() is called.  But it seems likely that many
  65  * applications will prefer to have the data stick around after decompression
  66  * finishes.)
  67  */
  68
  69 GLOBAL(boolean)
  70 jpeg_read_icc_profile(j_decompress_ptr cinfo, JOCTET **icc_data_ptr,
  71                       unsigned int *icc_data_len)
  72 {
  73   jpeg_saved_marker_ptr marker;
  74   int num_markers = 0;
  75   int seq_no;
  76   JOCTET *icc_data;
  77   unsigned int total_length;
  78 #define MAX_SEQ_NO  255         /* sufficient since marker numbers are bytes */
  79   char marker_present[MAX_SEQ_NO + 1];      /* 1 if marker found */
  80   unsigned int data_length[MAX_SEQ_NO + 1]; /* size of profile data in marker */
  81   unsigned int data_offset[MAX_SEQ_NO + 1]; /* offset for data in marker */
  82
  83   if (icc_data_ptr == NULL || icc_data_len == NULL)
  84     ERREXIT(cinfo, JERR_BUFFER_SIZE);
  85   if (cinfo->global_state < DSTATE_READY)
  86     ERREXIT1(cinfo, JERR_BAD_STATE, cinfo->global_state);
  87
  88   *icc_data_ptr = NULL;         /* avoid confusion if FALSE return */
  89   *icc_data_len = 0;
  90
  91   /* This first pass over the saved markers discovers whether there are
  92    * any ICC markers and verifies the consistency of the marker numbering.
  93    */
  94
  95   for (seq_no = 1; seq_no <= MAX_SEQ_NO; seq_no++)
  96     marker_present[seq_no] = 0;
  97
  98   for (marker = cinfo->marker_list; marker != NULL; marker = marker->next) {
  99     if (marker_is_icc(marker)) {
 100       if (num_markers == 0)
 101         num_markers = marker->data[13];
 102       else if (num_markers != marker->data[13]) {
 103         WARNMS(cinfo, JWRN_BOGUS_ICC);  /* inconsistent num_markers fields */
 104         return FALSE;
 105       }
 106       seq_no = marker->data[12];
 107       if (seq_no <= 0 || seq_no > num_markers) {
 108         WARNMS(cinfo, JWRN_BOGUS_ICC);  /* bogus sequence number */
 109         return FALSE;
 110       }
 111       if (marker_present[seq_no]) {
 112         WARNMS(cinfo, JWRN_BOGUS_ICC);  /* duplicate sequence numbers */
 113         return FALSE;
 114       }
 115       marker_present[seq_no] = 1;
 116       data_length[seq_no] = marker->data_length - ICC_OVERHEAD_LEN;
 117     }
 118   }
 119
 120   if (num_markers == 0)
 121     return FALSE;
 122
 123   /* Check for missing markers, count total space needed,
 124    * compute offset of each marker's part of the data.
 125    */
 126
 127   total_length = 0;
 128   for (seq_no = 1; seq_no <= num_markers; seq_no++) {
 129     if (marker_present[seq_no] == 0) {
 130       WARNMS(cinfo, JWRN_BOGUS_ICC);  /* missing sequence number */
 131       return FALSE;
 132     }
 133     data_offset[seq_no] = total_length;
 134     total_length += data_length[seq_no];
 135   }
 136
 137   if (total_length == 0) {
 138     WARNMS(cinfo, JWRN_BOGUS_ICC);  /* found only empty markers? */
 139     return FALSE;
 140   }
 141
 142   /* Allocate space for assembled data */
 143   icc_data = (JOCTET *)malloc(total_length * sizeof(JOCTET));
 144   if (icc_data == NULL)
 145     ERREXIT1(cinfo, JERR_OUT_OF_MEMORY, 11);  /* oops, out of memory */
 146
 147   /* and fill it in */
 148   for (marker = cinfo->marker_list; marker != NULL; marker = marker->next) {
 149     if (marker_is_icc(marker)) {
 150       JOCTET FAR *src_ptr;
 151       JOCTET *dst_ptr;
 152       unsigned int length;
 153       seq_no = marker->data[12];
 154       dst_ptr = icc_data + data_offset[seq_no];
 155       src_ptr = marker->data + ICC_OVERHEAD_LEN;
 156       length = data_length[seq_no];
 157       while (length--) {
 158         *dst_ptr++ = *src_ptr++;
 159       }
 160     }
 161   }
 162
 163   *icc_data_ptr = icc_data;
 164   *icc_data_len = total_length;
 165
 166   return TRUE;
 167 }