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
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.
16 #define JPEG_INTERNALS
21 #ifndef HAVE_STDLIB_H /* <stdlib.h> should declare malloc() */
22 extern void *malloc(size_t size
);
26 #define ICC_MARKER (JPEG_APP0 + 2) /* JPEG marker code for ICC */
27 #define ICC_OVERHEAD_LEN 14 /* size of non-profile data in APP2 */
31 * Handy subroutine to test whether a saved marker is an ICC profile marker.
35 marker_is_icc(jpeg_saved_marker_ptr marker
)
38 marker
->marker
== ICC_MARKER
&&
39 marker
->data_length
>= ICC_OVERHEAD_LEN
&&
40 /* verify the identifying string */
41 GETJOCTET(marker
->data
[0]) == 0x49 &&
42 GETJOCTET(marker
->data
[1]) == 0x43 &&
43 GETJOCTET(marker
->data
[2]) == 0x43 &&
44 GETJOCTET(marker
->data
[3]) == 0x5F &&
45 GETJOCTET(marker
->data
[4]) == 0x50 &&
46 GETJOCTET(marker
->data
[5]) == 0x52 &&
47 GETJOCTET(marker
->data
[6]) == 0x4F &&
48 GETJOCTET(marker
->data
[7]) == 0x46 &&
49 GETJOCTET(marker
->data
[8]) == 0x49 &&
50 GETJOCTET(marker
->data
[9]) == 0x4C &&
51 GETJOCTET(marker
->data
[10]) == 0x45 &&
52 GETJOCTET(marker
->data
[11]) == 0x0;
57 * See if there was an ICC profile in the JPEG file being read; if so,
58 * reassemble and return the profile data.
60 * TRUE is returned if an ICC profile was found, FALSE if not. If TRUE is
61 * returned, *icc_data_ptr is set to point to the returned data, and
62 * *icc_data_len is set to its length.
64 * IMPORTANT: the data at *icc_data_ptr is allocated with malloc() and must be
65 * freed by the caller with free() when the caller no longer needs it.
66 * (Alternatively, we could write this routine to use the IJG library's memory
67 * allocator, so that the data would be freed implicitly when
68 * jpeg_finish_decompress() is called. But it seems likely that many
69 * applications will prefer to have the data stick around after decompression
74 jpeg_read_icc_profile(j_decompress_ptr cinfo
, JOCTET
**icc_data_ptr
,
75 unsigned int *icc_data_len
)
77 jpeg_saved_marker_ptr marker
;
81 unsigned int total_length
;
82 #define MAX_SEQ_NO 255 /* sufficient since marker numbers are bytes */
83 char marker_present
[MAX_SEQ_NO
+ 1]; /* 1 if marker found */
84 unsigned int data_length
[MAX_SEQ_NO
+ 1]; /* size of profile data in marker */
85 unsigned int data_offset
[MAX_SEQ_NO
+ 1]; /* offset for data in marker */
87 if (icc_data_ptr
== NULL
|| icc_data_len
== NULL
)
88 ERREXIT(cinfo
, JERR_BUFFER_SIZE
);
89 if (cinfo
->global_state
< DSTATE_READY
)
90 ERREXIT1(cinfo
, JERR_BAD_STATE
, cinfo
->global_state
);
92 *icc_data_ptr
= NULL
; /* avoid confusion if FALSE return */
95 /* This first pass over the saved markers discovers whether there are
96 * any ICC markers and verifies the consistency of the marker numbering.
99 for (seq_no
= 1; seq_no
<= MAX_SEQ_NO
; seq_no
++)
100 marker_present
[seq_no
] = 0;
102 for (marker
= cinfo
->marker_list
; marker
!= NULL
; marker
= marker
->next
) {
103 if (marker_is_icc(marker
)) {
104 if (num_markers
== 0)
105 num_markers
= GETJOCTET(marker
->data
[13]);
106 else if (num_markers
!= GETJOCTET(marker
->data
[13])) {
107 WARNMS(cinfo
, JWRN_BOGUS_ICC
); /* inconsistent num_markers fields */
110 seq_no
= GETJOCTET(marker
->data
[12]);
111 if (seq_no
<= 0 || seq_no
> num_markers
) {
112 WARNMS(cinfo
, JWRN_BOGUS_ICC
); /* bogus sequence number */
115 if (marker_present
[seq_no
]) {
116 WARNMS(cinfo
, JWRN_BOGUS_ICC
); /* duplicate sequence numbers */
119 marker_present
[seq_no
] = 1;
120 data_length
[seq_no
] = marker
->data_length
- ICC_OVERHEAD_LEN
;
124 if (num_markers
== 0)
127 /* Check for missing markers, count total space needed,
128 * compute offset of each marker's part of the data.
132 for (seq_no
= 1; seq_no
<= num_markers
; seq_no
++) {
133 if (marker_present
[seq_no
] == 0) {
134 WARNMS(cinfo
, JWRN_BOGUS_ICC
); /* missing sequence number */
137 data_offset
[seq_no
] = total_length
;
138 total_length
+= data_length
[seq_no
];
141 if (total_length
== 0) {
142 WARNMS(cinfo
, JWRN_BOGUS_ICC
); /* found only empty markers? */
146 /* Allocate space for assembled data */
147 icc_data
= (JOCTET
*)malloc(total_length
* sizeof(JOCTET
));
148 if (icc_data
== NULL
)
149 ERREXIT1(cinfo
, JERR_OUT_OF_MEMORY
, 11); /* oops, out of memory */
152 for (marker
= cinfo
->marker_list
; marker
!= NULL
; marker
= marker
->next
) {
153 if (marker_is_icc(marker
)) {
157 seq_no
= GETJOCTET(marker
->data
[12]);
158 dst_ptr
= icc_data
+ data_offset
[seq_no
];
159 src_ptr
= marker
->data
+ ICC_OVERHEAD_LEN
;
160 length
= data_length
[seq_no
];
162 *dst_ptr
++ = *src_ptr
++;
167 *icc_data_ptr
= icc_data
;
168 *icc_data_len
= total_length
;