mapnik/src/image_util.cpp

/*****************************************************************************
 *
 * This file is part of Mapnik (c++ mapping toolkit)
 *
 * Copyright (C) 2011 Artem Pavlenko
 *
 * This library is free software; you can redistribute it and/or
 * modify it under the terms of the GNU Lesser General Public
 * License as published by the Free Software Foundation; either
 * version 2.1 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
 * Lesser General Public License for more details.
 *
 * You should have received a copy of the GNU Lesser General Public
 * License along with this library; if not, write to the Free Software
 * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA  02110-1301  USA
 *
 *****************************************************************************/

extern "C"
{
#include <png.h>
}

// mapnik
#include <mapnik/image_util.hpp>
#include <mapnik/png_io.hpp>
#include <mapnik/tiff_io.hpp>
#include <mapnik/graphics.hpp>
#include <mapnik/memory.hpp>
#include <mapnik/image_view.hpp>
#include <mapnik/palette.hpp>
#include <mapnik/map.hpp>
#include <mapnik/util/conversions.hpp>
#include <mapnik/span_image_filter.hpp>
// jpeg
#if defined(HAVE_JPEG)
#include <mapnik/jpeg_io.hpp>
#endif

#ifdef HAVE_CAIRO
#include <mapnik/cairo_renderer.hpp>
#include <cairo-features.h>
#endif

// boost
#include <boost/foreach.hpp>
#include <boost/tokenizer.hpp>

// stl
#include <string>
#include <iostream>
#include <fstream>
#include <sstream>

// agg
#include "agg_image_accessors.h"
#include "agg_pixfmt_rgba.h"
#include "agg_rasterizer_scanline_aa.h"
#include "agg_renderer_scanline.h"
#include "agg_rendering_buffer.h"
#include "agg_scanline_u.h"
//#include "agg_scanline_p.h"
#include "agg_span_allocator.h"
#include "agg_span_image_filter_rgba.h"
#include "agg_span_interpolator_linear.h"
#include "agg_trans_affine.h"
#include "agg_image_filters.h"

namespace mapnik
{


template <typename T>
std::string save_to_string(T const& image,
                           std::string const& type,
                           rgba_palette const& palette)
{
    std::ostringstream ss(std::ios::out|std::ios::binary);
    save_to_stream(image, ss, type, palette);
    return ss.str();
}

template <typename T>
std::string save_to_string(T const& image,
                           std::string const& type)
{
    std::ostringstream ss(std::ios::out|std::ios::binary);
    save_to_stream(image, ss, type);
    return ss.str();
}

template <typename T>
void save_to_file(T const& image,
                  std::string const& filename,
                  std::string const& type,
                  rgba_palette const& palette)
{
    std::ofstream file (filename.c_str(), std::ios::out| std::ios::trunc|std::ios::binary);
    if (file)
    {
        save_to_stream(image, file, type, palette);
    }
    else throw ImageWriterException("Could not write file to " + filename );
}

template <typename T>
void save_to_file(T const& image,
                  std::string const& filename,
                  std::string const& type)
{
    std::ofstream file (filename.c_str(), std::ios::out| std::ios::trunc|std::ios::binary);
    if (file)
    {
        save_to_stream(image, file, type);
    }
    else throw ImageWriterException("Could not write file to " + filename );
}

void handle_png_options(std::string const& type,
                        int * colors,
                        int * compression,
                        int * strategy,
                        int * trans_mode,
                        double * gamma,
                        bool * use_octree)
{
    if (type == "png" || type == "png24" || type == "png32")
    {
        // Shortcut when the user didn't specify any flags after the colon.
        // Paletted images specify "png8 or png256".
        *colors = -1;
        return;
    }
    // TODO - convert to spirit parser
    if (type.length() > 6){
        boost::char_separator<char> sep(":");
        boost::tokenizer< boost::char_separator<char> > tokens(type, sep);
        BOOST_FOREACH(std::string t, tokens)
        {
            if (t == "png" || t == "png24" || t == "png32")
            {
                *colors = -1;
            }
            else if (t == "m=h")
            {
                *use_octree = false;
            }
            else if (t == "m=o")
            {
                *use_octree = true;
            }
            else if (boost::algorithm::starts_with(t, "c="))
            {
                if (*colors < 0)
                    throw ImageWriterException("invalid color parameter: unavailable for true color images");

                if (!mapnik::util::string2int(t.substr(2),*colors) || *colors < 0 || *colors > 256)
                    throw ImageWriterException("invalid color parameter: " + t.substr(2));
            }
            else if (boost::algorithm::starts_with(t, "t="))
            {
                if (*colors < 0)
                    throw ImageWriterException("invalid trans_mode parameter: unavailable for true color images");

                if (!mapnik::util::string2int(t.substr(2),*trans_mode) || *trans_mode < 0 || *trans_mode > 2)
                    throw ImageWriterException("invalid trans_mode parameter: " + t.substr(2));
            }
            else if (boost::algorithm::starts_with(t, "g="))
            {
                if (*colors < 0)
                    throw ImageWriterException("invalid gamma parameter: unavailable for true color images");
                if (!mapnik::util::string2double(t.substr(2),*gamma) || *gamma < 0)
                {
                    throw ImageWriterException("invalid gamma parameter: " + t.substr(2));
                }
            }
            else if (boost::algorithm::starts_with(t, "z="))
            {
                /*
                  #define Z_NO_COMPRESSION         0
                  #define Z_BEST_SPEED             1
                  #define Z_BEST_COMPRESSION       9
                  #define Z_DEFAULT_COMPRESSION  (-1)
                */
                if (!mapnik::util::string2int(t.substr(2),*compression)
                    || *compression < Z_DEFAULT_COMPRESSION
                    || *compression > Z_BEST_COMPRESSION)
                {
                    throw ImageWriterException("invalid compression parameter: " + t.substr(2) + " (only -1 through 9 are valid)");
                }
            }
            else if (boost::algorithm::starts_with(t, "s="))
            {
                std::string const& s = t.substr(2);
                if (s == "default")
                {
                    *strategy = Z_DEFAULT_STRATEGY;
                }
                else if (s == "filtered")
                {
                    *strategy = Z_FILTERED;
                }
                else if (s == "huff")
                {
                    *strategy = Z_HUFFMAN_ONLY;
                }
                else if (s == "rle")
                {
                    *strategy = Z_RLE;
                }
                else
                {
                    throw ImageWriterException("invalid compression strategy parameter: " + s);
                }
            }
        }
    }
}

template <typename T>
void save_to_stream(T const& image,
                    std::ostream & stream,
                    std::string const& type,
                    rgba_palette const& palette)
{
    if (stream && image.width() > 0 && image.height() > 0)
    {
        //all this should go into image_writer factory
        std::string t = boost::algorithm::to_lower_copy(type);
        if (t == "png" || boost::algorithm::starts_with(t, "png"))
        {
            int colors  = 256;
            int compression = Z_DEFAULT_COMPRESSION;
            int strategy = Z_DEFAULT_STRATEGY;
            int trans_mode = -1;
            double gamma = -1;
            bool use_octree = true;

            handle_png_options(t,
                               &colors,
                               &compression,
                               &strategy,
                               &trans_mode,
                               &gamma,
                               &use_octree);

            if (palette.valid())
                save_as_png8_pal(stream, image, palette, compression, strategy);
            else if (colors < 0)
                save_as_png(stream, image, compression, strategy);
            else if (use_octree)
                save_as_png8_oct(stream, image, colors, compression, strategy);
            else
                save_as_png8_hex(stream, image, colors, compression, strategy, trans_mode, gamma);
        }
        else if (boost::algorithm::starts_with(t, "tif"))
        {
            throw ImageWriterException("palettes are not currently supported when writing to tiff format (yet)");
        }
#if defined(HAVE_JPEG)
        else if (boost::algorithm::starts_with(t, "jpeg"))
        {
            throw ImageWriterException("palettes are not currently supported when writing to jpeg format");
        }
#endif
        else throw ImageWriterException("unknown file type: " + type);
    }
    else throw ImageWriterException("Could not write to empty stream" );
}


template <typename T>
void save_to_stream(T const& image,
                    std::ostream & stream,
                    std::string const& type)
{
    if (stream && image.width() > 0 && image.height() > 0)
    {
        //all this should go into image_writer factory
        std::string t = boost::algorithm::to_lower_copy(type);
        if (t == "png" || boost::algorithm::starts_with(t, "png"))
        {
            int colors  = 256;
            int compression = Z_DEFAULT_COMPRESSION;
            int strategy = Z_DEFAULT_STRATEGY;
            int trans_mode = -1;
            double gamma = -1;
            bool use_octree = true;

            handle_png_options(t,
                               &colors,
                               &compression,
                               &strategy,
                               &trans_mode,
                               &gamma,
                               &use_octree);

            if (colors < 0)
                save_as_png(stream, image, compression, strategy);
            else if (use_octree)
                save_as_png8_oct(stream, image, colors, compression, strategy);
            else
                save_as_png8_hex(stream, image, colors, compression, strategy, trans_mode, gamma);
        }
        else if (boost::algorithm::starts_with(t, "tif"))
        {
            save_as_tiff(stream, image);
        }
#if defined(HAVE_JPEG)
        else if (boost::algorithm::starts_with(t, "jpeg"))
        {
            int quality = 85;
            std::string const& val = t.substr(4);
            if (!val.empty())
            {
                if (!mapnik::util::string2int(val,quality) || quality < 0 || quality > 100)
                {
                    throw ImageWriterException("invalid jpeg quality: '" + val + "'");
                }
            }
            save_as_jpeg(stream, quality, image);
        }
#endif
        else throw ImageWriterException("unknown file type: " + type);
    }
    else throw ImageWriterException("Could not write to empty stream" );
}

template <typename T>
void save_to_file(T const& image, std::string const& filename)
{
    boost::optional<std::string> type = type_from_filename(filename);
    if (type)
    {
        save_to_file<T>(image, filename, *type);
    }
}

template <typename T>
void save_to_file(T const& image, std::string const& filename, rgba_palette const& palette)
{
    boost::optional<std::string> type = type_from_filename(filename);
    if (type)
    {
        save_to_file<T>(image, filename, *type, palette);
    }
}

#if defined(HAVE_CAIRO)
// TODO - move to separate cairo_io.hpp
void save_to_cairo_file(mapnik::Map const& map, std::string const& filename)
{
    boost::optional<std::string> type = type_from_filename(filename);
    if (type)
    {
        save_to_cairo_file(map,filename,*type);
    }
}

void save_to_cairo_file(mapnik::Map const& map,
                        std::string const& filename,
                        std::string const& type)
{
    std::ofstream file (filename.c_str(), std::ios::out|std::ios::trunc|std::ios::binary);
    if (file)
    {
        Cairo::RefPtr<Cairo::Surface> surface;
        unsigned width = map.width();
        unsigned height = map.height();
        if (type == "pdf")
        {
#if defined(CAIRO_HAS_PDF_SURFACE)
            surface = Cairo::PdfSurface::create(filename,width,height);
#else
            throw ImageWriterException("PDFSurface not supported in the cairo backend");
#endif
        }
#if defined(CAIRO_HAS_SVG_SURFACE)
        else if (type == "svg")
        {
            surface = Cairo::SvgSurface::create(filename,width,height);
        }
#endif
#if defined(CAIRO_HAS_PS_SURFACE)
        else if (type == "ps")
        {
            surface = Cairo::PsSurface::create(filename,width,height);
        }
#endif
#if defined(CAIRO_HAS_IMAGE_SURFACE)
        else if (type == "ARGB32")
        {
            surface = Cairo::ImageSurface::create(Cairo::FORMAT_ARGB32,width,height);
        }
        else if (type == "RGB24")
        {
            surface = Cairo::ImageSurface::create(Cairo::FORMAT_RGB24,width,height);
        }
#endif
        else
        {
            throw ImageWriterException("unknown file type: " + type);
        }

        Cairo::RefPtr<Cairo::Context> context = Cairo::Context::create(surface);

        // TODO - expose as user option
        /*
          if (type == "ARGB32" || type == "RGB24")
          {
          context->set_antialias(Cairo::ANTIALIAS_NONE);
          }
        */


        mapnik::cairo_renderer<Cairo::Context> ren(map, context);
        ren.apply();

        if (type == "ARGB32" || type == "RGB24")
        {
            surface->write_to_png(filename);
        }
        surface->finish();
    }
}

#endif

template void save_to_file<image_data_32>(image_data_32 const&,
                                          std::string const&,
                                          std::string const&);

template void save_to_file<image_data_32>(image_data_32 const&,
                                          std::string const&,
                                          std::string const&,
                                          rgba_palette const& palette);

template void save_to_file<image_data_32>(image_data_32 const&,
                                          std::string const&);

template void save_to_file<image_data_32>(image_data_32 const&,
                                          std::string const&,
                                          rgba_palette const& palette);

template std::string save_to_string<image_data_32>(image_data_32 const&,
                                                   std::string const&);

template std::string save_to_string<image_data_32>(image_data_32 const&,
                                                   std::string const&,
                                                   rgba_palette const& palette);

template void save_to_file<image_view<image_data_32> > (image_view<image_data_32> const&,
                                                        std::string const&,
                                                        std::string const&);

template void save_to_file<image_view<image_data_32> > (image_view<image_data_32> const&,
                                                        std::string const&,
                                                        std::string const&,
                                                        rgba_palette const& palette);

template void save_to_file<image_view<image_data_32> > (image_view<image_data_32> const&,
                                                        std::string const&);

template void save_to_file<image_view<image_data_32> > (image_view<image_data_32> const&,
                                                        std::string const&,
                                                        rgba_palette const& palette);

template std::string save_to_string<image_view<image_data_32> > (image_view<image_data_32> const&,
                                                                 std::string const&);

template std::string save_to_string<image_view<image_data_32> > (image_view<image_data_32> const&,
                                                                 std::string const&,
                                                                 rgba_palette const& palette);



// Image scaling functions

scaling_method_e get_scaling_method_by_name (std::string name)
{
    // TODO - make into proper ENUMS
    if (name == "fast" || name == "near")
        return SCALING_NEAR;
    else if (name == "bilinear")
        return SCALING_BILINEAR;
    else if (name == "cubic" || name == "bicubic")
        return SCALING_BICUBIC;
    else if (name == "spline16")
        return SCALING_SPLINE16;
    else if (name == "spline36")
        return SCALING_SPLINE36;
    else if (name == "hanning")
        return SCALING_HANNING;
    else if (name == "hamming")
        return SCALING_HAMMING;
    else if (name == "hermite")
        return SCALING_HERMITE;
    else if (name == "kaiser")
        return SCALING_KAISER;
    else if (name == "quadric")
        return SCALING_QUADRIC;
    else if (name == "catrom")
        return SCALING_CATROM;
    else if (name == "gaussian")
        return SCALING_GAUSSIAN;
    else if (name == "bessel")
        return SCALING_BESSEL;
    else if (name == "mitchell")
        return SCALING_MITCHELL;
    else if (name == "sinc")
        return SCALING_SINC;
    else if (name == "lanczos")
        return SCALING_LANCZOS;
    else if (name == "blackman")
        return SCALING_BLACKMAN;
    else
        return SCALING_NEAR;
}

// this has been replaced by agg impl - see https://trac.mapnik.org/ticket/656

template <typename Image>
void scale_image_bilinear_old (Image& target,const Image& source, double x_off_f, double y_off_f)
{

    int source_width=source.width();
    int source_height=source.height();

    int target_width=target.width();
    int target_height=target.height();

    if (source_width<1 || source_height<1 ||
        target_width<1 || target_height<1) return;
    int x=0,y=0,xs=0,ys=0;
    int tw2 = target_width/2;
    int th2 = target_height/2;
    int offs_x = rint((source_width-target_width-x_off_f*2*source_width)/2);
    int offs_y = rint((source_height-target_height-y_off_f*2*source_height)/2);
    unsigned yprt, yprt1, xprt, xprt1;

    //no scaling or subpixel offset
    if (target_height == source_height && target_width == source_width && offs_x == 0 && offs_y == 0){
        for (y=0;y<target_height;++y)
            target.setRow(y,source.getRow(y),target_width);
        return;
    }

    for (y=0;y<target_height;++y)
    {
        ys = (y*source_height+offs_y)/target_height;
        int ys1 = ys+1;
        if (ys1>=source_height)
            ys1--;
        if (ys<0)
            ys=ys1=0;
        if (source_height/2<target_height)
            yprt = (y*source_height+offs_y)%target_height;
        else
            yprt = th2;
        yprt1 = target_height-yprt;
        for (x=0;x<target_width;++x)
        {
            xs = (x*source_width+offs_x)/target_width;
            if (source_width/2<target_width)
                xprt = (x*source_width+offs_x)%target_width;
            else
                xprt = tw2;
            xprt1 = target_width-xprt;
            int xs1 = xs+1;
            if (xs1>=source_width)
                xs1--;
            if (xs<0)
                xs=xs1=0;

            unsigned a = source(xs,ys);
            unsigned b = source(xs1,ys);
            unsigned c = source(xs,ys1);
            unsigned d = source(xs1,ys1);
            unsigned out=0;
            unsigned t = 0;

            for(int i=0; i<4; i++){
                unsigned p,r,s;
                // X axis
                p = a&0xff;
                r = b&0xff;
                if (p!=r)
                    r = (r*xprt+p*xprt1+tw2)/target_width;
                p = c&0xff;
                s = d&0xff;
                if (p!=s)
                    s = (s*xprt+p*xprt1+tw2)/target_width;
                // Y axis
                if (r!=s)
                    r = (s*yprt+r*yprt1+th2)/target_height;
                // channel up
                out |= r << t;
                t += 8;
                a >>= 8;
                b >>= 8;
                c >>= 8;
                d >>= 8;
            }
            target(x,y)=out;
        }
    }
}


template <typename Image>
void scale_image_bilinear8 (Image& target,const Image& source, double x_off_f, double y_off_f)
{

    int source_width=source.width();
    int source_height=source.height();

    int target_width=target.width();
    int target_height=target.height();

    if (source_width<1 || source_height<1 ||
        target_width<1 || target_height<1) return;
    int x=0,y=0,xs=0,ys=0;
    int tw2 = target_width/2;
    int th2 = target_height/2;
    int offs_x = rint((source_width-target_width-x_off_f*2*source_width)/2);
    int offs_y = rint((source_height-target_height-y_off_f*2*source_height)/2);
    unsigned yprt, yprt1, xprt, xprt1;

    //no scaling or subpixel offset
    if (target_height == source_height && target_width == source_width && offs_x == 0 && offs_y == 0){
        for (y=0;y<target_height;++y)
            target.setRow(y,source.getRow(y),target_width);
        return;
    }

    for (y=0;y<target_height;++y)
    {
        ys = (y*source_height+offs_y)/target_height;
        int ys1 = ys+1;
        if (ys1>=source_height)
            ys1--;
        if (ys<0)
            ys=ys1=0;
        if (source_height/2<target_height)
            yprt = (y*source_height+offs_y)%target_height;
        else
            yprt = th2;
        yprt1 = target_height-yprt;
        for (x=0;x<target_width;++x)
        {
            xs = (x*source_width+offs_x)/target_width;
            if (source_width/2<target_width)
                xprt = (x*source_width+offs_x)%target_width;
            else
                xprt = tw2;
            xprt1 = target_width-xprt;
            int xs1 = xs+1;
            if (xs1>=source_width)
                xs1--;
            if (xs<0)
                xs=xs1=0;

            unsigned a = source(xs,ys);
            unsigned b = source(xs1,ys);
            unsigned c = source(xs,ys1);
            unsigned d = source(xs1,ys1);
            unsigned p,r,s;
            // X axis
            p = a&0xff;
            r = b&0xff;
            if (p!=r)
                r = (r*xprt+p*xprt1+tw2)/target_width;
            p = c&0xff;
            s = d&0xff;
            if (p!=s)
                s = (s*xprt+p*xprt1+tw2)/target_width;
            // Y axis
            if (r!=s)
                r = (s*yprt+r*yprt1+th2)/target_height;
            target(x,y)=(0xff<<24) | (r<<16) | (r<<8) | r;
        }
    }
}

template <typename Image>
void scale_image_agg (Image& target,const Image& source, scaling_method_e scaling_method, double scale_factor, double x_off_f, double y_off_f, double filter_radius, double ratio)
{
    typedef agg::pixfmt_rgba32 pixfmt;
    typedef agg::pixfmt_rgba32_pre pixfmt_pre;
    typedef agg::renderer_base<pixfmt_pre> renderer_base;

    // define some stuff we'll use soon
    agg::rasterizer_scanline_aa<> ras;
    agg::scanline_u8 sl;
    agg::span_allocator<agg::rgba8> sa;
    agg::image_filter_lut filter;

    // initialize source AGG buffer
    agg::rendering_buffer rbuf_src((unsigned char*)source.getBytes(), source.width(), source.height(), source.width() * 4);
    pixfmt pixf_src(rbuf_src);
    typedef agg::image_accessor_clone<pixfmt> img_src_type;
    img_src_type img_src(pixf_src);

    // initialise destination AGG buffer (with transparency)
    agg::rendering_buffer rbuf_dst((unsigned char*)target.getBytes(), target.width(), target.height(), target.width() * 4);
    pixfmt_pre pixf_dst(rbuf_dst);
    renderer_base rb_dst(pixf_dst);
    rb_dst.clear(agg::rgba(0, 0, 0, 0));

    // create a scaling matrix
    agg::trans_affine img_mtx;
    img_mtx /= agg::trans_affine_scaling(scale_factor * ratio, scale_factor * ratio);

    // create a linear interpolator for our scaling matrix
    typedef agg::span_interpolator_linear<> interpolator_type;
    interpolator_type interpolator(img_mtx);

    // draw an anticlockwise polygon to render our image into
    double scaled_width = source.width() * scale_factor;
    double scaled_height = source.height() * scale_factor;
    ras.reset();
    ras.move_to_d(x_off_f,                y_off_f);
    ras.line_to_d(x_off_f + scaled_width, y_off_f);
    ras.line_to_d(x_off_f + scaled_width, y_off_f + scaled_height);
    ras.line_to_d(x_off_f,                y_off_f + scaled_height);

    switch(scaling_method)
    {
    case SCALING_NEAR:
    {
        typedef agg::span_image_filter_rgba_nn<img_src_type, interpolator_type> span_gen_type;
        span_gen_type sg(img_src, interpolator);
        agg::render_scanlines_aa(ras, sl, rb_dst, sa, sg);
        return;
    }
    case SCALING_BILINEAR:
        filter.calculate(agg::image_filter_bilinear(), true); break;
    case SCALING_BICUBIC:
        filter.calculate(agg::image_filter_bicubic(), true); break;
    case SCALING_SPLINE16:
        filter.calculate(agg::image_filter_spline16(), true); break;
    case SCALING_SPLINE36:
        filter.calculate(agg::image_filter_spline36(), true); break;
    case SCALING_HANNING:
        filter.calculate(agg::image_filter_hanning(), true); break;
    case SCALING_HAMMING:
        filter.calculate(agg::image_filter_hamming(), true); break;
    case SCALING_HERMITE:
        filter.calculate(agg::image_filter_hermite(), true); break;
    case SCALING_KAISER:
        filter.calculate(agg::image_filter_kaiser(), true); break;
    case SCALING_QUADRIC:
        filter.calculate(agg::image_filter_quadric(), true); break;
    case SCALING_CATROM:
        filter.calculate(agg::image_filter_catrom(), true); break;
    case SCALING_GAUSSIAN:
        filter.calculate(agg::image_filter_gaussian(), true); break;
    case SCALING_BESSEL:
        filter.calculate(agg::image_filter_bessel(), true); break;
    case SCALING_MITCHELL:
        filter.calculate(agg::image_filter_mitchell(), true); break;
    case SCALING_SINC:
        filter.calculate(agg::image_filter_sinc(filter_radius), true); break;
    case SCALING_LANCZOS:
        filter.calculate(agg::image_filter_lanczos(filter_radius), true); break;
    case SCALING_BLACKMAN:
        filter.calculate(agg::image_filter_blackman(filter_radius), true); break;
    }
    typedef mapnik::span_image_resample_rgba_affine<img_src_type> span_gen_type;
    span_gen_type sg(img_src, interpolator, filter);
    agg::render_scanlines_aa(ras, sl, rb_dst, sa, sg);
}


void save_to_file(image_32 const& image,std::string const& file)
{
    save_to_file<image_data_32>(image.data(), file);
}

void save_to_file (image_32 const& image,
                   std::string const& file,
                   std::string const& type)
{
    save_to_file<image_data_32>(image.data(), file, type);
}

void save_to_file (image_32 const& image,
                   std::string const& file,
                   std::string const& type,
                   rgba_palette const& palette)
{
    save_to_file<image_data_32>(image.data(), file, type, palette);
}

std::string save_to_string(image_32 const& image,
                           std::string const& type)
{
    return save_to_string<image_data_32>(image.data(), type);
}

std::string save_to_string(image_32 const& image,
                           std::string const& type,
                           rgba_palette const& palette)
{
    return save_to_string<image_data_32>(image.data(), type, palette);
}

template void scale_image_agg<image_data_32> (image_data_32& target,const image_data_32& source, scaling_method_e scaling_method, double scale_factor, double x_off_f, double y_off_f, double filter_radius, double ratio);

template void scale_image_bilinear_old<image_data_32> (image_data_32& target,const image_data_32& source, double x_off_f, double y_off_f);

template void scale_image_bilinear8<image_data_32> (image_data_32& target,const image_data_32& source, double x_off_f, double y_off_f);

}