小试ImageMagik——开发篇

/*
 * 雷霄骅
 * leixiaohua1020@126.com
 * http://blog.csdn.net/leixiaohua1020
 * 中国传媒大学/数字电视技术
 */
//创建Image对象，
// create a blank image canvas with 640x480 size and ‘white‘ color as background:
 Image blank_image( Geometry(640, 480), Color(MaxRGB, MaxRGB, MaxRGB, 0));
 // or also, by using the automatic C++ type conversions for the arguments:
 Image blank_image("640x480", "white");
 
 // create an image from URL
 Image url_image("http://www.serverName.com/image.gif");
 Image local_file_image("my_image.gif");   // here the URL points to the local filesystem
//获取/设置属性
// Canvas geometry
// returns an unsigned int representing the my_image width
unsigned int Image::columns();
// returns an unsigned int representing the my_image heigth
unsigned int Image::rows();
// sets the my_image format; the format string can be "GIF", etc
void Image::magick("png");
// returns a string value representing the image format (e.g. “GIF”, “JPEG”, etc)
string Image::magick();
//读取/保存图像文件
// Reading the contents of a disk file into an image object can be performed
Image my_image();  // create an *empty* image using the default Image constructor
// read a GIF image file from disk; the image format is automatically set to GIF
my_image.read("aGIFImageFile.gif");
// Writing an Image object to a disk file. set the "format" attribute of my_image to PNG
my_image.magick("png");
// write to disk an image file
my_image.write("file_name_explicit_extension.gif");

/*
 * 雷霄骅
 * leixiaohua1020@126.com
 * http://blog.csdn.net/leixiaohua1020
 * 中国传媒大学/数字电视技术
 */
#include <windows.h>
#include <wand/magick_wand.h>
 
void test_wand(void)
{
         MagickWand *m_wand = NULL;
        
         int width,height;
        
         MagickWandGenesis();
        
         m_wand = NewMagickWand();
         // Read the image - all you need to do is change "logo:" to some other
         // filename to have this resize and, if necessary, convert a different file
         MagickReadImage(m_wand,"logo:");
        
         // Get the image‘s width and height
         width = MagickGetImageWidth(m_wand);
         height = MagickGetImageHeight(m_wand);
        
         // Cut them in half but make sure they don‘t underflow
         if((width /= 2) < 1)width = 1;
         if((height /= 2) < 1)height = 1;
        
         // Resize the image using the Lanczos filter
         // The blur factor is a "double", where > 1 is blurry, < 1 is sharp
         // I haven‘t figured out how you would change the blur parameter of MagickResizeImage
         // on the command line so I have set it to its default of one.
         MagickResizeImage(m_wand,width,height,LanczosFilter,1);
        
         // Set the compression quality to 95 (high quality = low compression)
         MagickSetImageCompressionQuality(m_wand,95);
        
         /* Write the new image */
         MagickWriteImage(m_wand,"logo_resize.jpg");
        
         /* Clean up */
         if(m_wand)m_wand = DestroyMagickWand(m_wand);
        
         MagickWandTerminus();
}

/*
 * 雷霄骅
 * leixiaohua1020@126.com
 * http://blog.csdn.net/leixiaohua1020
 * 中国传媒大学/数字电视技术
 */
#include <windows.h>
#include <wand/magick_wand.h>
 
void test_wand(void)
{
         MagickWand *m_wand = NULL;
         PixelWand *p_wand;
         int w,h;
 
         MagickWandGenesis();
 
         /* Create a wand */
         m_wand = NewMagickWand();
         p_wand = NewPixelWand();
 
         // Change this to whatever colour you like - e.g. "none"
         PixelSetColor(p_wand, "blue");
         /* Read the input image */
         MagickReadImage(m_wand,"logo:");
         w = MagickGetImageWidth(m_wand);
         h = MagickGetImageHeight(m_wand);
         MagickSetImageBackgroundColor(m_wand,p_wand);
         // This centres the original image on the new canvas.
         // Note that the extent‘s offset is relative to the
         // top left corner of the *original* image, so adding an extent
         // around it means that the offset will be negative
         MagickExtentImage(m_wand,1024,768,-(1024-w)/2,-(768-h)/2);
         MagickWriteImage(m_wand,"logo_extent.jpg");
 
         /* Tidy up */
         m_wand = DestroyMagickWand(m_wand);
         p_wand = DestroyPixelWand(p_wand);
         MagickWandTerminus();
}