jpegio.cpp

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/*
 * Author: Steven Ludtke, 04/10/2003 (sludtke@bcm.edu)
 * Copyright (c) 2000-2006 Baylor College of Medicine
 *
 * This software is issued under a joint BSD/GNU license. You may use the
 * source code in this file under either license. However, note that the
 * complete EMAN2 and SPARX software packages have some GPL dependencies,
 * so you are responsible for compliance with the licenses of these packages
 * if you opt to use BSD licensing. The warranty disclaimer below holds
 * in either instance.
 *
 * This complete copyright notice must be included in any revised version of the
 * source code. Additional authorship citations may be added, but existing
 * author citations must be preserved.
 *
 * This program is free software; you can redistribute it and/or modify
 * it under the terms of the GNU General Public License as published by
 * the Free Software Foundation; either version 2 of the License, or
 * (at your option) any later version.
 *
 * This program 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 General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License
 * along with this program; if not, write to the Free Software
 * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
 *
 * */
 
#ifdef USE_JPEG
 
#ifdef WIN32
#include <windows.h>
#endif  // WIN32
 
#include <stdlib.h>
#include <stdio.h>
#include <math.h>
#include "jpegio.h"
#include "geometry.h"
#include "util.h"
 
using namespace EMAN;
 
JpegIO::JpegIO(const string & fname, IOMode rw)
:       ImageIO(fname, rw),
        rendermin(0.0), rendermax(0.0), renderbits(16)
{}
 
JpegIO::~JpegIO()
{
        if (file) {
                fclose(file);
                file = NULL;
        }
 
}
 
void JpegIO::init()
{
        ENTERFUNC;
 
        if (initialized) {
                return;
        }
 
        initialized = true;
 
        bool is_new_file = false;
        file = sfopen(filename, rw_mode, &is_new_file, true);
 
        if (! is_new_file) {
                throw ImageReadException(filename, "JPEG reading not supported");
        }
        else {
                cinfo.err = jpeg_std_error(&jerr);
                jpeg_create_compress(&cinfo);
                jpeg_stdio_dest(&cinfo, file);
        }
 
        rendermin = 0.0;
        rendermax = 0.0;
 
        jpegqual  = 75;
 
        EXITFUNC;
}
 
bool JpegIO::is_valid(const void *)
{
//      ENTERFUNC;
 
        return false;
}
 
// int JpegIO::read_header(Dict & dict, int image_index,
// const Region * area, bool)
 
int JpegIO::read_header(Dict &, int, const Region *, bool)
{
        ENTERFUNC;
 
        throw ImageReadException(filename, "JPEG reading not supported");
 
        EXITFUNC;
 
        return 0;
}
 
int JpegIO::write_header(const Dict & dict, int image_index,
                                                const Region* area, EMUtil::EMDataType, bool)
{
        ENTERFUNC;
 
        // single image format, index can only be zero
 
        if (image_index == -1) {
                image_index = 0;
        }
 
        if (image_index != 0) {
                throw ImageWriteException(filename,
                        "JPEG file does not support stack.");
        }
 
        check_write_access(rw_mode, image_index);
 
        if ((int) dict["nz"] != 1) {
                LOGERR("Only support 2D JPEG file write");
 
                return 1;
        }
 
//      rendermin = (float)dict["render_min"];  // float value representing black in the output
//      rendermax = (float)dict["render_max"];  // float value representign white in the output
 
        EMUtil::getRenderLimits(dict, rendermin, rendermax, renderbits);
 
        jpegqual = (int)dict["jpeg_quality"];
        if (jpegqual == 0) jpegqual = 75;
 
        cinfo.image_width  = (int) dict["nx"];  /* image width and height, in pixels */
        cinfo.image_height = (int) dict["ny"];
 
        if (area) {
                cinfo.image_width  = (int) area->size[0];
                cinfo.image_height = (int) area->size[1];
        }
 
        cinfo.input_components = 1;     /* # of color components per pixel */
        cinfo.in_color_space = JCS_GRAYSCALE; /* colorspace of input image */
 
        jpeg_set_defaults(&cinfo);
        jpeg_set_quality(&cinfo, jpegqual, TRUE);
 
        EXITFUNC;
 
        return 0;
}
 
int JpegIO::read_data(float *, int, const Region *, bool)
{
        ENTERFUNC;
 
        EXITFUNC;
 
        return 0;
}
 
int JpegIO::write_data(float *data, int image_index, const Region* area,
                                          EMUtil::EMDataType, bool)
{
        ENTERFUNC;
 
        if (image_index > 0)
                 throw ImageWriteException("N/A", "JPEG files are single-image only");
 
        if (area && (area->size[0] != cinfo.image_width ||
                 area->size[1] != cinfo.image_height))
                 throw ImageWriteException("N/A", "No region writing for JPEG images");
 
        int nx = cinfo.image_width, ny = cinfo.image_height;
 
        // If we didn't get any parameters in 'render_min' or 'render_max',
        // we need to find some good ones.
 
        if (renderbits==0 || renderbits>8) renderbits=8;
        EMUtil::getRenderMinMax(data, nx, ny, rendermin, rendermax, renderbits);
 
        unsigned char *cdata = (unsigned char *)malloc(nx+1);
 
        /* Flip the image vertically, since EMAN use top-left corner as image origin
           But PNG use bottom-left corner as image origin */
        // convert and write the data 1 scanline at a time
 
        JSAMPROW rp[1];
        rp[0] = cdata;
 
        jpeg_start_compress(&cinfo, TRUE);
 
        for (int i=ny-1; i>=0; i--) {
                for (int j=0; j<nx; j++) {
                        if (data[i*nx+j] <= rendermin) cdata[j] = 0;
                        else if (data[i*nx+j] >= rendermax) cdata[j] = 255;
                        else cdata[j]= (int)((data[i*nx+j]-rendermin)/
                                                                (rendermax-rendermin)*256.0);
                }
 
                jpeg_write_scanlines(&cinfo, rp, 1);
        }
 
        jpeg_finish_compress(&cinfo);
        jpeg_destroy_compress(&cinfo);
 
        free(cdata);
 
        EXITFUNC;
 
        return 0;
}
 
int JpegIO::get_nimg() {
        return 0;
}
 
void JpegIO::flush()
{
 
}
 
bool JpegIO::is_complex_mode()
{
        return false;
}
 
bool JpegIO::is_image_big_endian()
{
        return true;
}
 
#endif  //USE_JPEG