iccjpeg library

third_party/iccjpeg/iccjpeg.h

+/*
+ * iccprofile.h
+ *
+ * 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.
+ *
+ * NOTE: this code would need surgery to work on 16-bit-int machines
+ * with ICC profiles exceeding 64K bytes in size.  See iccprofile.c
+ * for details.
+ */
+
+#include <stdio.h>              /* needed to define "FILE", "NULL" */
+#include "jpeglib.h"
+
+
+/*
+ * 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.)
+ */
+
+extern void write_icc_profile JPP((j_compress_ptr cinfo,
+                                   const JOCTET *icc_data_ptr,
+                                   unsigned int icc_data_len));
+
+
+/*
+ * Reading a JPEG file that may contain an ICC profile requires two steps:
+ *
+ * 1. After jpeg_create_decompress() but before jpeg_read_header(),
+ *    call setup_read_icc_profile().  This routine tells the IJG library
+ *    to save in memory any APP2 markers it may find in the file.
+ *
+ * 2. After jpeg_read_header(), call read_icc_profile() to find out
+ *    whether there was a profile and obtain it if so.
+ */
+
+
+/*
+ * Prepare for reading an ICC profile
+ */
+
+extern void setup_read_icc_profile JPP((j_decompress_ptr cinfo));
+
+
+/*
+ * 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.
+ *
+ * IMPORTANT: the data at **icc_data_ptr has been allocated with malloc()
+ * and must be freed by the caller with free() when the caller no longer
+ * needs it.  (Alternatively, we could write this routine to use the
+ * IJG library's memory allocator, so that the data would be freed implicitly
+ * at jpeg_finish_decompress() time.  But it seems likely that many apps
+ * will prefer to have the data stick around after decompression finishes.)
+ */
+
+extern boolean read_icc_profile JPP((j_decompress_ptr cinfo,
+                                     JOCTET **icc_data_ptr,
+                                     unsigned int *icc_data_len));