jdicc.c (5409B)
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 }