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/* This Source Code Form is subject to the terms of the Mozilla Public
* License, v. 2.0. If a copy of the MPL was not distributed with this
/*
* iccjpeg.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.
*/
#ifndef mozilla_image_decoders_iccjpeg_h
#define mozilla_image_decoders_iccjpeg_h
#include <stdio.h> /* needed to define "FILE", "NULL" */
#include "jpeglib.h"
/*
* 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));
#endif // mozilla_image_decoders_iccjpeg_h