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| resize.cxx |
--- | --- | ---

Resize an image using Geometric Transformations
Usage: `resize infile outfile`

    /************************************************************************/
    /*                                                                      */
    /*               Copyright 1998-2002 by Ullrich Koethe                  */
    /*       Cognitive Systems Group, University of Hamburg, Germany        */
    /*                                                                      */
    /*    This file is part of the VIGRA computer vision library.           */
    /*    ( Version 1.3.2, Jan 27 2005 )                                    */
    /*    You may use, modify, and distribute this software according       */
    /*    to the terms stated in the LICENSE file included in               */
    /*    the VIGRA distribution.                                           */
    /*                                                                      */
    /*    The VIGRA Website is                                              */
    /*        http://kogs-www.informatik.uni-hamburg.de/~koethe/vigra/      */
    /*    Please direct questions, bug reports, and contributions to        */
    /*        koethe@informatik.uni-hamburg.de                              */
    /*                                                                      */
    /*  THIS SOFTWARE IS PROVIDED AS IS AND WITHOUT ANY EXPRESS OR          */
    /*  IMPLIED WARRANTIES, INCLUDING, WITHOUT LIMITATION, THE IMPLIED      */
    /*  WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE. */
    /*                                                                      */
    /************************************************************************/

    #include <iostream>
    #include "vigra/stdimage.hxx"
    #include "vigra/resizeimage.hxx"
    #include "vigra/impex.hxx"

    using namespace vigra;

    int main(int argc, char ** argv)
    {
        if(argc != 3)
        {
            std::cout << "Usage: " << argv[0] << " infile outfile" << std::endl;
            std::cout << "(supported formats: " << vigra::impexListFormats() << ")" << std::endl;

            return 1;
        }

        try
        {
            // read image given as first argument
            // file type is determined automatically
            vigra::ImageImportInfo info(argv[1]);

            double sizefactor;
            std::cerr << "Resize factor ? ";
            std::cin >> sizefactor;
            int method;
            std::cerr << "Method (0 - pixel repetition, 1 - linear, 2 - spline ? ";
            std::cin >> method;

            // calculate new image size
            int nw = (int)(sizefactor*(info.width()-1) + 1.5);
            int nh = (int)(sizefactor*(info.height()-1) + 1.5);

            if(info.isGrayscale())
            {
                // create a gray scale image of appropriate size
                vigra::BImage in(info.width(), info.height());
                vigra::BImage out(nw, nh);

                // import the image just read
                importImage(info, destImage(in));

                switch(method)
                {
                  case 0:
                    // resize the image, using a bi-cubic spline algorithms
                    resizeImageNoInterpolation(srcImageRange(in),
                        destImageRange(out));
                    break;
                  case 1:
                    // resize the image, using a bi-cubic spline algorithms
                    resizeImageLinearInterpolation(srcImageRange(in),
                        destImageRange(out));
                    break;
                  default:
                    // resize the image, using a bi-cubic spline algorithms
                    resizeImageSplineInterpolation(srcImageRange(in),
                        destImageRange(out));
                }

                // write the image to the file given as second argument
                // the file type will be determined from the file name's extension
                exportImage(srcImageRange(out), vigra::ImageExportInfo(argv[2]));
            }
            else
            {
                // create a RGB image of appropriate size
                vigra::BRGBImage in(info.width(), info.height());
                vigra::BRGBImage out(nw, nh);

                // import the image just read
                importImage(info, destImage(in));

                switch(method)
                {
                  case 0:
                    // resize the image, using a bi-cubic spline algorithms
                    resizeImageNoInterpolation(srcImageRange(in),
                        destImageRange(out));
                    break;
                  case 1:
                    // resize the image, using a bi-cubic spline algorithms
                    resizeImageLinearInterpolation(srcImageRange(in),
                        destImageRange(out));
                    break;
                  default:
                    // resize the image, using a bi-cubic spline algorithms
                    resizeImageSplineInterpolation(srcImageRange(in),
                        destImageRange(out));
                }

                // write the image to the file given as second argument
                // the file type will be determined from the file name's extension
                exportImage(srcImageRange(out), vigra::ImageExportInfo(argv[2]));
            }
        }
        catch (vigra::StdException & e)
        {
            // catch any errors that might have occured and print their reason
            std::cout << e.what() << std::endl;
            return 1;
        }

        return 0;
    }

© Ullrich Köthe (koethe@informatik.uni-hamburg.de) Cognitive Systems Group, University of Hamburg, Germany | html generated using doxygen and Python VIGRA 1.3.2 (27 Jan 2005)