fltk/src/Fl_JPEG_Image.cxx
Michael R Sweet 1c399af444 Update source file headers with STR web page.
git-svn-id: file:///fltk/svn/fltk/branches/branch-1.1@4288 ea41ed52-d2ee-0310-a9c1-e6b18d33e121
2005-04-16 00:13:17 +00:00

176 lines
4.0 KiB
C++

//
// "$Id$"
//
// Fl_JPEG_Image routines.
//
// Copyright 1997-2005 by Easy Software Products.
// Image support donated by Matthias Melcher, Copyright 2000.
//
// This library is free software; you can redistribute it and/or
// modify it under the terms of the GNU Library General Public
// License as published by the Free Software Foundation; either
// version 2 of the License, or (at your option) any later version.
//
// This library is distributed in the hope that it will be useful,
// but WITHOUT ANY WARRANTY; without even the implied warranty of
// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
// Library General Public License for more details.
//
// You should have received a copy of the GNU Library General Public
// License along with this library; if not, write to the Free Software
// Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307
// USA.
//
// Please report all bugs and problems on the following page:
//
// http://www.fltk.org/str.php
//
// Contents:
//
// Fl_JPEG_Image::Fl_JPEG_Image() - Load a JPEG image file.
//
//
// Include necessary header files...
//
#include <FL/Fl_JPEG_Image.H>
#include <config.h>
#include <stdio.h>
#include <stdlib.h>
#include <setjmp.h>
// Some releases of the Cygwin JPEG libraries don't have a correctly
// updated header file for the INT32 data type; the following define
// from Shane Hill seems to be a usable workaround...
#if defined(WIN32) && defined(__CYGWIN__)
# define XMD_H
#endif // WIN32 && __CYGWIN__
extern "C"
{
#ifdef HAVE_LIBJPEG
# include <jpeglib.h>
#endif // HAVE_LIBJPEG
}
//
// Custom JPEG error handling structure...
//
#ifdef HAVE_LIBJPEG
struct fl_jpeg_error_mgr {
jpeg_error_mgr pub_; // Destination manager...
jmp_buf errhand_; // Error handler
};
#endif // HAVE_LIBJPEG
//
// Error handler for JPEG files...
//
#ifdef HAVE_LIBJPEG
extern "C" {
static void
fl_jpeg_error_handler(j_common_ptr dinfo) { // I - Decompressor info
longjmp(((fl_jpeg_error_mgr *)(dinfo->err))->errhand_, 1);
return;
}
static void
fl_jpeg_output_handler(j_common_ptr dinfo) { // I - Decompressor info
return;
}
}
#endif // HAVE_LIBJPEG
//
// 'Fl_JPEG_Image::Fl_JPEG_Image()' - Load a JPEG image file.
//
Fl_JPEG_Image::Fl_JPEG_Image(const char *jpeg) // I - File to load
: Fl_RGB_Image(0,0,0) {
#ifdef HAVE_LIBJPEG
FILE *fp; // File pointer
jpeg_decompress_struct dinfo; // Decompressor info
fl_jpeg_error_mgr jerr; // Error handler info
JSAMPROW row; // Sample row pointer
// Clear data...
alloc_array = 0;
array = (uchar *)0;
// Open the image file...
if ((fp = fopen(jpeg, "rb")) == NULL) return;
// Setup the decompressor info and read the header...
dinfo.err = jpeg_std_error((jpeg_error_mgr *)&jerr);
jerr.pub_.error_exit = fl_jpeg_error_handler;
jerr.pub_.output_message = fl_jpeg_output_handler;
if (setjmp(jerr.errhand_))
{
// JPEG error handling...
if (array) jpeg_finish_decompress(&dinfo);
jpeg_destroy_decompress(&dinfo);
fclose(fp);
w(0);
h(0);
d(0);
if (array) {
delete[] (uchar *)array;
array = 0;
alloc_array = 0;
}
return;
}
jpeg_create_decompress(&dinfo);
jpeg_stdio_src(&dinfo, fp);
jpeg_read_header(&dinfo, 1);
dinfo.quantize_colors = (boolean)FALSE;
dinfo.out_color_space = JCS_RGB;
dinfo.out_color_components = 3;
dinfo.output_components = 3;
jpeg_calc_output_dimensions(&dinfo);
w(dinfo.output_width);
h(dinfo.output_height);
d(dinfo.output_components);
array = new uchar[w() * h() * d()];
alloc_array = 1;
jpeg_start_decompress(&dinfo);
while (dinfo.output_scanline < dinfo.output_height) {
row = (JSAMPROW)(array +
dinfo.output_scanline * dinfo.output_width *
dinfo.output_components);
jpeg_read_scanlines(&dinfo, &row, (JDIMENSION)1);
}
jpeg_finish_decompress(&dinfo);
jpeg_destroy_decompress(&dinfo);
fclose(fp);
#endif // HAVE_LIBJPEG
}
//
// End of "$Id$".
//