c image scaling image clipping function to achieve of proportional scaling

  • 2020-05-30 20:59:37
  • OfStack

The so-called c# image processing advanced should be done mostly based on the.net framework class library


using system;
using system.collections.generic;
using system.text;
using system.io;
using system.drawing;
using system.drawing.drawing2d;
using system.drawing.imaging;
namespace wujian.common
{
    /// <summary>
    ///  Image processing class 
    /// </summary>
    public class ptimage
    {
        #region  Square cut and scale 
        /// <summary>
        ///  Square cut 
        ///  Take the center of the image as the axis, intercept the square shape, and then scale equably 
        ///  For avatars 
        /// </summary>
        /// <param name="postedfile"> The original image httppostedfile object </param>
        /// <param name="filesaveurl"> Thumbnail location </param>
        /// <param name="side"> Specified side length (tetragonal) </param>
        /// <param name="quality"> Quality (range) 0-100 ) </param>
        public static void cutforsquare(system.web.httppostedfile postedfile, string filesaveurl, int side, int quality)
        {
            // Create a directory 
            string dir = path.getdirectoryname(filesaveurl);
            if (!directory.exists(dir))
                directory.createdirectory(dir);
            // Raw image (get the original image create object and use the color management information embedded in the stream) 
            system.drawing.image initimage = system.drawing.image.fromstream(postedfile.inputstream, true);
            // Original image width and height are smaller than the template, do not handle, directly saved 
            if (initimage.width <= side && initimage.height <= side)
            {
                initimage.save(filesaveurl, system.drawing.imaging.imageformat.jpeg);
            }
            else
            {
                // The width and height of the original image 
                int initwidth = initimage.width;
                int initheight = initimage.height;
                // The non - square cut first to the square 
                if (initwidth != initheight)
                {
                    // Screenshot of the object 
                    system.drawing.image pickedimage = null;
                    system.drawing.graphics pickedg = null;
                    // A broad than a high cross 
                    if (initwidth > initheight)
                    {
                        // Object instantiation 
                        pickedimage = new system.drawing.bitmap(initheight, initheight);
                        pickedg = system.drawing.graphics.fromimage(pickedimage);
                        // Set up the quality 
                        pickedg.interpolationmode = system.drawing.drawing2d.interpolationmode.highqualitybicubic;
                        pickedg.smoothingmode = system.drawing.drawing2d.smoothingmode.highquality;
                        // positioning 
                        rectangle fromr = new rectangle((initwidth - initheight) / 2, 0, initheight, initheight);
                        rectangle tor = new rectangle(0, 0, initheight, initheight);
                        // drawing 
                        pickedg.drawimage(initimage, tor, fromr, system.drawing.graphicsunit.pixel);
                        // Reset the wide 
                        initwidth = initheight;
                    }
                    // A vertical diagram larger than the width 
                    else
                    {
                        // Object instantiation 
                        pickedimage = new system.drawing.bitmap(initwidth, initwidth);
                        pickedg = system.drawing.graphics.fromimage(pickedimage);
                        // Set up the quality 
                        pickedg.interpolationmode = system.drawing.drawing2d.interpolationmode.highqualitybicubic;
                        pickedg.smoothingmode = system.drawing.drawing2d.smoothingmode.highquality;
                        // positioning 
                        rectangle fromr = new rectangle(0, (initheight - initwidth) / 2, initwidth, initwidth);
                        rectangle tor = new rectangle(0, 0, initwidth, initwidth);
                        // drawing 
                        pickedg.drawimage(initimage, tor, fromr, system.drawing.graphicsunit.pixel);
                        // Reset the high 
                        initheight = initwidth;
                    }
                    // Assign the screenshot object to the original 
                    initimage = (system.drawing.image)pickedimage.clone();
                    // Release screenshot resources 
                    pickedg.dispose();
                    pickedimage.dispose();
                }
                // Thumbnail object 
                system.drawing.image resultimage = new system.drawing.bitmap(side, side);
                system.drawing.graphics resultg = system.drawing.graphics.fromimage(resultimage);
                // Set up the quality 
                resultg.interpolationmode = system.drawing.drawing2d.interpolationmode.highqualitybicubic;
                resultg.smoothingmode = system.drawing.drawing2d.smoothingmode.highquality;
                // Empty the canvas with the specified background color 
                resultg.clear(color.white);
                // Draw thumbnails 
                resultg.drawimage(initimage, new system.drawing.rectangle(0, 0, side, side), new system.drawing.rectangle(0, 0, initwidth, initheight), system.drawing.graphicsunit.pixel);
                // Critical quality control 
                // Gets an array of system encoding types , Contains the jpeg,bmp,png,gif,tiff
                imagecodecinfo[] icis = imagecodecinfo.getimageencoders();
                imagecodecinfo ici = null;
                foreach (imagecodecinfo i in icis)
                {
                    if (i.mimetype == "image/jpeg" || i.mimetype == "image/bmp" || i.mimetype == "image/png" || i.mimetype == "image/gif")
                    {
                        ici = i;
                    }
                }
                encoderparameters ep = new encoderparameters(1);
                ep.param[0] = new encoderparameter(system.drawing.imaging.encoder.quality, (long)quality);
                // Save the thumbnail 
                resultimage.save(filesaveurl, ici, ep);
                // Release key quality control resources 
                ep.dispose();
                // Release the thumbnail resource 
                resultg.dispose();
                resultimage.dispose();
                // Release the original image resource 
                initimage.dispose();
            }
        }
        /// <summary>
        ///  Square cut 
        ///  Take the center of the image as the axis, intercept the square shape, and then scale equably 
        ///  For avatars 
        /// </summary>
        /// <param name="postedfile"> The original image httppostedfile object </param>
        /// <param name="filesaveurl"> Thumbnail location </param>
        /// <param name="side"> Specified side length (tetragonal) </param>
        /// <param name="quality"> Quality (range) 0-100 ) </param>
        public static void cutforsquare(system.io.stream fromfile, string filesaveurl, int side, int quality)
        {
            // Create a directory 
            string dir = path.getdirectoryname(filesaveurl);
            if (!directory.exists(dir))
                directory.createdirectory(dir);
            // Raw image (get the original image create object and use the color management information embedded in the stream) 
            system.drawing.image initimage = system.drawing.image.fromstream(fromfile, true);
            // Original image width and height are smaller than the template, do not handle, directly saved 
            if (initimage.width <= side && initimage.height <= side)
            {
                initimage.save(filesaveurl, system.drawing.imaging.imageformat.jpeg);
            }
            else
            {
                // The width and height of the original image 
                int initwidth = initimage.width;
                int initheight = initimage.height;
                // The non - square cut first to the square 
                if (initwidth != initheight)
                {
                    // Screenshot of the object 
                    system.drawing.image pickedimage = null;
                    system.drawing.graphics pickedg = null;
                    // A broad than a high cross 
                    if (initwidth > initheight)
                    {
                        // Object instantiation 
                        pickedimage = new system.drawing.bitmap(initheight, initheight);
                        pickedg = system.drawing.graphics.fromimage(pickedimage);
                        // Set up the quality 
                        pickedg.interpolationmode = system.drawing.drawing2d.interpolationmode.highqualitybicubic;
                        pickedg.smoothingmode = system.drawing.drawing2d.smoothingmode.highquality;
                        // positioning 
                        rectangle fromr = new rectangle((initwidth - initheight) / 2, 0, initheight, initheight);
                        rectangle tor = new rectangle(0, 0, initheight, initheight);
                        // drawing 
                        pickedg.drawimage(initimage, tor, fromr, system.drawing.graphicsunit.pixel);
                        // Reset the wide 
                        initwidth = initheight;
                    }
                    // A vertical diagram larger than the width 
                    else
                    {
                        // Object instantiation 
                        pickedimage = new system.drawing.bitmap(initwidth, initwidth);
                        pickedg = system.drawing.graphics.fromimage(pickedimage);
                        // Set up the quality 
                        pickedg.interpolationmode = system.drawing.drawing2d.interpolationmode.highqualitybicubic;
                        pickedg.smoothingmode = system.drawing.drawing2d.smoothingmode.highquality;
                        // positioning 
                        rectangle fromr = new rectangle(0, (initheight - initwidth) / 2, initwidth, initwidth);
                        rectangle tor = new rectangle(0, 0, initwidth, initwidth);
                        // drawing 
                        pickedg.drawimage(initimage, tor, fromr, system.drawing.graphicsunit.pixel);
                        // Reset the high 
                        initheight = initwidth;
                    }
                    // Assign the screenshot object to the original 
                    initimage = (system.drawing.image)pickedimage.clone();
                    // Release screenshot resources 
                    pickedg.dispose();
                    pickedimage.dispose();
                }
                // Thumbnail object 
                system.drawing.image resultimage = new system.drawing.bitmap(side, side);
                system.drawing.graphics resultg = system.drawing.graphics.fromimage(resultimage);
                // Set up the quality 
                resultg.interpolationmode = system.drawing.drawing2d.interpolationmode.highqualitybicubic;
                resultg.smoothingmode = system.drawing.drawing2d.smoothingmode.highquality;
                // Empty the canvas with the specified background color 
                resultg.clear(color.white);
                // Draw thumbnails 
                resultg.drawimage(initimage, new system.drawing.rectangle(0, 0, side, side), new system.drawing.rectangle(0, 0, initwidth, initheight), system.drawing.graphicsunit.pixel);
                // Critical quality control 
                // Gets an array of system encoding types , Contains the jpeg,bmp,png,gif,tiff
                imagecodecinfo[] icis = imagecodecinfo.getimageencoders();
                imagecodecinfo ici = null;
                foreach (imagecodecinfo i in icis)
                {
                    if (i.mimetype == "image/jpeg" || i.mimetype == "image/bmp" || i.mimetype == "image/png" || i.mimetype == "image/gif")
                    {
                        ici = i;
                    }
                }
                encoderparameters ep = new encoderparameters(1);
                ep.param[0] = new encoderparameter(system.drawing.imaging.encoder.quality, (long)quality);
                // Save the thumbnail 
                resultimage.save(filesaveurl, ici, ep);
                // Release key quality control resources 
                ep.dispose();
                // Release the thumbnail resource 
                resultg.dispose();
                resultimage.dispose();
                // Release the original image resource 
                initimage.dispose();
            }
        }
        #endregion
        #region  Fixed template clipping and scaling 
        /// <summary>
        ///  Specify width and length clipping 
        ///  Crop the image to the maximum range of template proportions and scale to template size 
        /// </summary>
        /// <param name="postedfile"> The original image httppostedfile object </param>
        /// <param name="filesaveurl"> Save the path </param>
        /// <param name="maxwidth"> Maximum width ( unit :px)</param>
        /// <param name="maxheight"> The largest high ( unit :px)</param>
        /// <param name="quality"> Quality (range) 0-100 ) </param>
        public static void cutforcustom(system.web.httppostedfile postedfile, string filesaveurl, int maxwidth, int maxheight, int quality)
        {
            // Get the original image from the file and use the color management information embedded in the stream 
            system.drawing.image initimage = system.drawing.image.fromstream(postedfile.inputstream, true);
            // Original image width and height are smaller than the template, do not handle, directly saved 
            if (initimage.width <= maxwidth && initimage.height <= maxheight)
            {
                initimage.save(filesaveurl, system.drawing.imaging.imageformat.jpeg);
            }
            else
            {
                // The ratio of width to height of a template 
                double templaterate = (double)maxwidth / maxheight;
                // The ratio of width to height of the original image 
                double initrate = (double)initimage.width / initimage.height;
                // The original image is proportional to the template and scaled directly 
                if (templaterate == initrate)
                {
                    // Generate the final image by template size 
                    system.drawing.image templateimage = new system.drawing.bitmap(maxwidth, maxheight);
                    system.drawing.graphics templateg = system.drawing.graphics.fromimage(templateimage);
                    templateg.interpolationmode = system.drawing.drawing2d.interpolationmode.high;
                    templateg.smoothingmode = system.drawing.drawing2d.smoothingmode.highquality;
                    templateg.clear(color.white);
                    templateg.drawimage(initimage, new system.drawing.rectangle(0, 0, maxwidth, maxheight), new system.drawing.rectangle(0, 0, initimage.width, initimage.height), system.drawing.graphicsunit.pixel);
                    templateimage.save(filesaveurl, system.drawing.imaging.imageformat.jpeg);
                }
                // The scale of the original and template is not equal 
                else
                {
                    // Cutting object 
                    system.drawing.image pickedimage = null;
                    system.drawing.graphics pickedg = null;
                    // positioning 
                    rectangle fromr = new rectangle(0, 0, 0, 0);// Clipping and positioning the original drawing 
                    rectangle tor = new rectangle(0, 0, 0, 0);// target 
                    // The width is cut for the standard 
                    if (templaterate > initrate)
                    {
                        // Clipping object instantiation 
                        pickedimage = new system.drawing.bitmap(initimage.width, (int)math.floor(initimage.width / templaterate));
                        pickedg = system.drawing.graphics.fromimage(pickedimage);
                        // Clipping source location 
                        fromr.x = 0;
                        fromr.y = (int)math.floor((initimage.height - initimage.width / templaterate) / 2);
                        fromr.width = initimage.width;
                        fromr.height = (int)math.floor(initimage.width / templaterate);
                        // Clipping target location 
                        tor.x = 0;
                        tor.y = 0;
                        tor.width = initimage.width;
                        tor.height = (int)math.floor(initimage.width / templaterate);
                    }
                    // Height is the standard for cutting 
                    else
                    {
                        pickedimage = new system.drawing.bitmap((int)math.floor(initimage.height * templaterate), initimage.height);
                        pickedg = system.drawing.graphics.fromimage(pickedimage);
                        fromr.x = (int)math.floor((initimage.width - initimage.height * templaterate) / 2);
                        fromr.y = 0;
                        fromr.width = (int)math.floor(initimage.height * templaterate);
                        fromr.height = initimage.height;
                        tor.x = 0;
                        tor.y = 0;
                        tor.width = (int)math.floor(initimage.height * templaterate);
                        tor.height = initimage.height;
                    }
                    // Set up the quality 
                    pickedg.interpolationmode = system.drawing.drawing2d.interpolationmode.highqualitybicubic;
                    pickedg.smoothingmode = system.drawing.drawing2d.smoothingmode.highquality;
                    // tailoring 
                    pickedg.drawimage(initimage, tor, fromr, system.drawing.graphicsunit.pixel);
                    // Generate the final image by template size 
                    system.drawing.image templateimage = new system.drawing.bitmap(maxwidth, maxheight);
                    system.drawing.graphics templateg = system.drawing.graphics.fromimage(templateimage);
                    templateg.interpolationmode = system.drawing.drawing2d.interpolationmode.high;
                    templateg.smoothingmode = system.drawing.drawing2d.smoothingmode.highquality;
                    templateg.clear(color.white);
                    templateg.drawimage(pickedimage, new system.drawing.rectangle(0, 0, maxwidth, maxheight), new system.drawing.rectangle(0, 0, pickedimage.width, pickedimage.height), system.drawing.graphicsunit.pixel);
                    // Critical quality control 
                    // Gets an array of system encoding types , Contains the jpeg,bmp,png,gif,tiff
                    imagecodecinfo[] icis = imagecodecinfo.getimageencoders();
                    imagecodecinfo ici = null;
                    foreach (imagecodecinfo i in icis)
                    {
                        if (i.mimetype == "image/jpeg" || i.mimetype == "image/bmp" || i.mimetype == "image/png" || i.mimetype == "image/gif")
                        {
                            ici = i;
                        }
                    }
                    encoderparameters ep = new encoderparameters(1);
                    ep.param[0] = new encoderparameter(system.drawing.imaging.encoder.quality, (long)quality);
                    // Save the thumbnail 
                    templateimage.save(filesaveurl, ici, ep);
                    //templateimage.save(filesaveurl, system.drawing.imaging.imageformat.jpeg);
                    // Release resources 
                    templateg.dispose();
                    templateimage.dispose();
                    pickedg.dispose();
                    pickedimage.dispose();
                }
            }
            // Release resources 
            initimage.dispose();
        }
        #endregion
        #region  Geometric scaling 
        /// <summary>
        ///  Scale the image proportionally 
        /// </summary>
        /// <param name="postedfile"> The original image httppostedfile object </param>
        /// <param name="savepath"> Thumbnail location </param>
        /// <param name="targetwidth"> Specified maximum width </param>
        /// <param name="targetheight"> The maximum height specified </param>
        /// <param name="watermarktext"> Watermark text ( for "" Means no watermark is used )</param>
        /// <param name="watermarkimage"> Watermark image path ( for "" Means no watermark is used )</param>
        public static void zoomauto(system.web.httppostedfile postedfile, string savepath, system.double targetwidth, system.double targetheight, string watermarktext, string watermarkimage)
        {
            // Create a directory 
            string dir = path.getdirectoryname(savepath);
            if (!directory.exists(dir))
                directory.createdirectory(dir);
            // Raw image (get the original image create object and use the color management information embedded in the stream) 
            system.drawing.image initimage = system.drawing.image.fromstream(postedfile.inputstream, true);
            // Original image width and height are smaller than the template, do not handle, directly saved 
            if (initimage.width <= targetwidth && initimage.height <= targetheight)
            {
                // Text watermarking 
                if (watermarktext != "")
                {
                    using (system.drawing.graphics gwater = system.drawing.graphics.fromimage(initimage))
                    {
                        system.drawing.font fontwater = new font(" blackbody ", 10);
                        system.drawing.brush brushwater = new solidbrush(color.white);
                        gwater.drawstring(watermarktext, fontwater, brushwater, 10, 10);
                        gwater.dispose();
                    }
                }
                // Transparent image watermarking 
                if (watermarkimage != "")
                {
                    if (file.exists(watermarkimage))
                    {
                        // Get watermark image 
                        using (system.drawing.image wrimage = system.drawing.image.fromfile(watermarkimage))
                        {
                            // Watermark drawing conditions: the original image width and height are greater than or equal to the watermark image 
                            if (initimage.width >= wrimage.width && initimage.height >= wrimage.height)
                            {
                                graphics gwater = graphics.fromimage(initimage);
                                // Transparent property 
                                imageattributes imgattributes = new imageattributes();
                                colormap colormap = new colormap();
                                colormap.oldcolor = color.fromargb(255, 0, 255, 0);
                                colormap.newcolor = color.fromargb(0, 0, 0, 0);
                                colormap[] remaptable = { colormap };
                                imgattributes.setremaptable(remaptable, coloradjusttype.bitmap);
                                float[][] colormatrixelements = { 
                                   new float[] {1.0f,  0.0f,  0.0f,  0.0f, 0.0f},
                                   new float[] {0.0f,  1.0f,  0.0f,  0.0f, 0.0f},
                                   new float[] {0.0f,  0.0f,  1.0f,  0.0f, 0.0f},
                                   new float[] {0.0f,  0.0f,  0.0f,  0.5f, 0.0f},// transparency :0.5
                                   new float[] {0.0f,  0.0f,  0.0f,  0.0f, 1.0f}
                                };
                                colormatrix wmcolormatrix = new colormatrix(colormatrixelements);
                                imgattributes.setcolormatrix(wmcolormatrix, colormatrixflag.default, coloradjusttype.bitmap);
                                gwater.drawimage(wrimage, new rectangle(initimage.width - wrimage.width, initimage.height - wrimage.height, wrimage.width, wrimage.height), 0, 0, wrimage.width, wrimage.height, graphicsunit.pixel, imgattributes);
                                gwater.dispose();
                            }
                            wrimage.dispose();
                        }
                    }
                }
                // save 
                initimage.save(savepath, system.drawing.imaging.imageformat.jpeg);
            }
            else
            {
                // Thumbnail width and height calculation 
                double newwidth = initimage.width;
                double newheight = initimage.height;
                // To be equal to (a cross or square) in height or width. 
                if (initimage.width > initimage.height || initimage.width == initimage.height)
                {
                    // If larger than the template 
                    if (initimage.width > targetwidth)
                    {
                        // Width to template, height to scale 
                        newwidth = targetwidth;
                        newheight = initimage.height * (targetwidth / initimage.width);
                    }
                }
                // Taller than wider (portrait) 
                else
                {
                    // If it's bigger than the template 
                    if (initimage.height > targetheight)
                    {
                        // Height to template, width to scale 
                        newheight = targetheight;
                        newwidth = initimage.width * (targetheight / initimage.height);
                    }
                }
                // Generate new 
                // new 1 a bmp The picture 
                system.drawing.image newimage = new system.drawing.bitmap((int)newwidth, (int)newheight);
                // new 1 A drawing board 
                system.drawing.graphics newg = system.drawing.graphics.fromimage(newimage);
                // Set up the quality 
                newg.interpolationmode = system.drawing.drawing2d.interpolationmode.highqualitybicubic;
                newg.smoothingmode = system.drawing.drawing2d.smoothingmode.highquality;
                // Set the background color 
         &nbs
                

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