/* jpeg-icc.c * * This file provides code to read and write International Color * Consortium (ICC) device profiles embedded in JFIF JPEG image files. * The ICC has defined a standard format for including such data in * JPEG "APP2" markers. The code given here does not know anything * about the internal structure of the ICC profile data; it just knows * how to put the profile data into a JPEG file being written, or get * it back out when reading. * * This code depends on new features added to the IJG JPEG library as of * IJG release 6b; it will not compile or work with older IJG versions. */ /* This code was originally copied from the jpegicc tool as found in * the lcms source code. This code comes with the following copyright * notice: * * Little cms * Copyright (C) 1998-2004 Marti Maria * * Permission is hereby granted, free of charge, to any person * obtaining a copy of this software and associated documentation * files (the "Software"), to deal in the Software without * restriction, including without limitation the rights to use, copy, * modify, merge, publish, distribute, sublicense, and/or sell copies * of the Software, and to permit persons to whom the Software is * furnished to do so, subject to the following conditions: * * The above copyright notice and this permission notice shall be * included in all copies or substantial portions of the Software. */ /* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND * NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS * BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN * ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN * CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE * SOFTWARE. */ #include "config.h" #include #include #include #include "jpeg-icc.h" /* * Since an ICC profile can be larger than the maximum size of a JPEG * marker (64K), we need provisions to split it into multiple markers. * The format defined by the ICC specifies one or more APP2 markers * containing the following data: * * Identifying string ASCII "ICC_PROFILE\0" (12 bytes) * Marker sequence number 1 for first APP2, 2 for next, etc (1 byte) * Number of markers Total number of APP2's used (1 byte) * Profile data (remainder of APP2 data) * Decoders should use the marker sequence numbers to reassemble the * profile, rather than assuming that the APP2 markers appear in the * correct sequence. */ #define ICC_MARKER (JPEG_APP0 + 2) /* JPEG marker code for ICC */ #define ICC_OVERHEAD_LEN 14 /* size of non-profile data in APP2 */ #define MAX_BYTES_IN_MARKER 65533 /* maximum data len of a JPEG marker */ #define MAX_DATA_BYTES_IN_MARKER (MAX_BYTES_IN_MARKER - ICC_OVERHEAD_LEN) /* * This routine writes the given ICC profile data into a JPEG file. * It *must* be called AFTER calling jpeg_start_compress() and BEFORE * the first call to jpeg_write_scanlines(). * (This ordering ensures that the APP2 marker(s) will appear after the * SOI and JFIF or Adobe markers, but before all else.) */ void jpeg_icc_write_profile (j_compress_ptr cinfo, const guchar *icc_data_ptr, guint icc_data_len) { unsigned int num_markers; /* total number of markers we'll write */ int cur_marker = 1; /* per spec, counting starts at 1 */ unsigned int length; /* number of bytes to write in this marker */ /* Calculate the number of markers we'll need, rounding up of course */ num_markers = icc_data_len / MAX_DATA_BYTES_IN_MARKER; if (num_markers * MAX_DATA_BYTES_IN_MARKER != icc_data_len) num_markers++; while (icc_data_len > 0) { /* length of profile to put in this marker */ length = icc_data_len; if (length > MAX_DATA_BYTES_IN_MARKER) length = MAX_DATA_BYTES_IN_MARKER; icc_data_len -= length; /* Write the JPEG marker header (APP2 code and marker length) */ jpeg_write_m_header(cinfo, ICC_MARKER, (unsigned int) (length + ICC_OVERHEAD_LEN)); /* Write the marker identifying string "ICC_PROFILE" (null-terminated). * We code it in this less-than-transparent way so that the code works * even if the local character set is not ASCII. */ jpeg_write_m_byte(cinfo, 0x49); jpeg_write_m_byte(cinfo, 0x43); jpeg_write_m_byte(cinfo, 0x43); jpeg_write_m_byte(cinfo, 0x5F); jpeg_write_m_byte(cinfo, 0x50); jpeg_write_m_byte(cinfo, 0x52); jpeg_write_m_byte(cinfo, 0x4F); jpeg_write_m_byte(cinfo, 0x46); jpeg_write_m_byte(cinfo, 0x49); jpeg_write_m_byte(cinfo, 0x4C); jpeg_write_m_byte(cinfo, 0x45); jpeg_write_m_byte(cinfo, 0x0); /* Add the sequencing info */ jpeg_write_m_byte(cinfo, cur_marker); jpeg_write_m_byte(cinfo, (int) num_markers); /* Add the profile data */ while (length--) { jpeg_write_m_byte(cinfo, *icc_data_ptr); icc_data_ptr++; } cur_marker++; } } /* * Handy subroutine to test whether a saved marker is an ICC profile marker. */ static boolean marker_is_icc (jpeg_saved_marker_ptr marker) { return marker->marker == ICC_MARKER && marker->data_length >= ICC_OVERHEAD_LEN && /* verify the identifying string */ GETJOCTET(marker->data[0]) == 0x49 && GETJOCTET(marker->data[1]) == 0x43 && GETJOCTET(marker->data[2]) == 0x43 && GETJOCTET(marker->data[3]) == 0x5F && GETJOCTET(marker->data[4]) == 0x50 && GETJOCTET(marker->data[5]) == 0x52 && GETJOCTET(marker->data[6]) == 0x4F && GETJOCTET(marker->data[7]) == 0x46 && GETJOCTET(marker->data[8]) == 0x49 && GETJOCTET(marker->data[9]) == 0x4C && GETJOCTET(marker->data[10]) == 0x45 && GETJOCTET(marker->data[11]) == 0x0; } /* * See if there was an ICC profile in the JPEG file being read; * if so, reassemble and return the profile data. * * TRUE is returned if an ICC profile was found, FALSE if not. * If TRUE is returned, *icc_data_ptr is set to point to the * returned data, and *icc_data_len is set to its length. * * NOTE: if the file contains invalid ICC APP2 markers, we just silently * return FALSE. You might want to issue an error message instead. */ gboolean jpeg_icc_read_profile (j_decompress_ptr cinfo, guchar **icc_data_ptr, guint *icc_data_len) { jpeg_saved_marker_ptr marker; int num_markers = 0; int seq_no; JOCTET *icc_data; unsigned int total_length; #define MAX_SEQ_NO 255 /* sufficient since marker numbers are bytes */ char marker_present[MAX_SEQ_NO+1]; /* 1 if marker found */ unsigned int data_length[MAX_SEQ_NO+1]; /* size of profile data in marker */ unsigned int data_offset[MAX_SEQ_NO+1]; /* offset for data in marker */ *icc_data_ptr = NULL; /* avoid confusion if FALSE return */ *icc_data_len = 0; /* This first pass over the saved markers discovers whether there are * any ICC markers and verifies the consistency of the marker numbering. */ for (seq_no = 1; seq_no <= MAX_SEQ_NO; seq_no++) marker_present[seq_no] = 0; for (marker = cinfo->marker_list; marker != NULL; marker = marker->next) { if (marker_is_icc(marker)) { if (num_markers == 0) num_markers = GETJOCTET(marker->data[13]); else if (num_markers != GETJOCTET(marker->data[13])) return FALSE; /* inconsistent num_markers fields */ seq_no = GETJOCTET(marker->data[12]); if (seq_no <= 0 || seq_no > num_markers) return FALSE; /* bogus sequence number */ if (marker_present[seq_no]) return FALSE; /* duplicate sequence numbers */ marker_present[seq_no] = 1; data_length[seq_no] = marker->data_length - ICC_OVERHEAD_LEN; } } if (num_markers == 0) return FALSE; /* Check for missing markers, count total space needed, * compute offset of each marker's part of the data. */ total_length = 0; for (seq_no = 1; seq_no <= num_markers; seq_no++) { if (marker_present[seq_no] == 0) return FALSE; /* missing sequence number */ data_offset[seq_no] = total_length; total_length += data_length[seq_no]; } if (total_length <= 0) return FALSE; /* found only empty markers? */ /* Allocate space for assembled data */ icc_data = g_try_malloc (total_length * sizeof(JOCTET)); if (icc_data == NULL) return FALSE; /* oops, out of memory */ /* and fill it in */ for (marker = cinfo->marker_list; marker != NULL; marker = marker->next) { if (marker_is_icc(marker)) { JOCTET FAR *src_ptr; JOCTET *dst_ptr; unsigned int length; seq_no = GETJOCTET(marker->data[12]); dst_ptr = icc_data + data_offset[seq_no]; src_ptr = marker->data + ICC_OVERHEAD_LEN; length = data_length[seq_no]; while (length--) { *dst_ptr++ = *src_ptr++; } } } *icc_data_ptr = icc_data; *icc_data_len = total_length; return TRUE; }