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/image_data.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>
// 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>
#include <algorithm>

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,
                        bool * use_miniz)
{
    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 (t == "e=miniz")
            {
                *use_miniz = 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 < 1 || *colors > 256)
                    throw ImageWriterException("invalid color parameter: " + t.substr(2));
            }
            else if (boost::algorithm::starts_with(t, "t="))
            {
                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 > 10) // use 10 here rather than Z_BEST_COMPRESSION (9) to allow for MZ_UBER_COMPRESSION
                {
                    throw ImageWriterException("invalid compression parameter: " + t.substr(2) + " (only -1 through 10 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 if (s == "fixed")
                {
                    *strategy = Z_FIXED;
                }
                else
                {
                    throw ImageWriterException("invalid compression strategy parameter: " + s);
                }
            }
        }
        if ((*use_miniz == false) && *compression > Z_BEST_COMPRESSION)
        {
            throw ImageWriterException("invalid compression value: (only -1 through 9 are valid)");
        }
    }
}

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)
    {
        std::string t = type;
        std::transform(t.begin(), t.end(), t.begin(), ::tolower);
        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;
            bool use_miniz = false;

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

            if (palette.valid())
            {
                save_as_png8_pal(stream, image, palette, compression, strategy, use_miniz);
            }
            else if (colors < 0)
            {
                save_as_png(stream, image, compression, strategy, trans_mode, use_miniz);
            }
            else if (use_octree)
            {
                save_as_png8_oct(stream, image, colors, compression, strategy, trans_mode, use_miniz);
            }
            else
            {
                save_as_png8_hex(stream, image, colors, compression, strategy, trans_mode, gamma, use_miniz);
            }
        }
        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)
    {
        std::string t = type;
        std::transform(t.begin(), t.end(), t.begin(), ::tolower);
        if (t == "png" || boost::algorithm::starts_with(t, "png"))
        {
            int colors  = 256;
            int compression = Z_DEFAULT_COMPRESSION; // usually mapped to z=6 in zlib
            int strategy = Z_DEFAULT_STRATEGY;
            int trans_mode = -1;
            double gamma = -1;
            bool use_octree = true;
            bool use_miniz = false;

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

            if (colors < 0)
            {
                save_as_png(stream, image, compression, strategy, trans_mode, use_miniz);
            }
            else if (use_octree)
            {
                save_as_png8_oct(stream, image, colors, compression, strategy, trans_mode, use_miniz);
            }
            else
            {
                save_as_png8_hex(stream, image, colors, compression, strategy, trans_mode, gamma, use_miniz);
            }
        }
        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, double scale_factor)
{
    boost::optional<std::string> type = type_from_filename(filename);
    if (type)
    {
        save_to_cairo_file(map,filename,*type,scale_factor);
    }
}

void save_to_cairo_file(mapnik::Map const& map,
                        std::string const& filename,
                        std::string const& type,
                        double scale_factor)
{
    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, scale_factor);
        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);

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);
}

}