readme.md

Aspose.Imaging .NET API allows to easy manipulate your png images or photos in your .NET application or Web service.

You can:

• Convert png image to raster formats;
• Create png image;
• Convert png image to vector formats;
• Compress png images;
• Specify bit depth of png image;
• Operate with transparent png images;
• Perform crop,rotate,resize and other typical operations to png images.

Interested ?

You may go further at : https://products.aspose.com/imaging/net/

apply-filter-method-in-png-image.cs

using Aspose.Imaging;
using Aspose.Imaging.FileFormats.Png;
using Aspose.Imaging.ImageOptions;
using System.IO;

string templatesFolder = @"c:\Users\USER\Downloads\templates\";
string dataDir = templatesFolder;

using (PngImage png = (PngImage)Image.Load(dataDir + "template.png"))
{
    // Create an instance of PngOptions, Set the PNG filter method and Save changes to the disc
    PngOptions options = new PngOptions();
    options.FilterType = PngFilterType.Paeth;
    png.Save(dataDir + "result.png", options);
}

File.Delete(dataDir + "result.png");

change-background-color-of-transparent-png.cs

using Aspose.Imaging;
using Aspose.Imaging.FileFormats.Png;
using Aspose.Imaging.ImageOptions;
using System.IO;

string templatesFolder = @"c:\Users\USER\Downloads\templates\";
string dataDir = templatesFolder;

// Create an instance of Image class and load a PNG image
using (Image img = Image.Load(dataDir + "template.png"))
{
    // Create an instance of RasterImage and get the pixels array by calling method LoadArgb32Pixels.
    RasterImage rasterImg = img as RasterImage;
    if (rasterImg != null)
    {
        int[] pixels = rasterImg.LoadArgb32Pixels(img.Bounds);
        if (pixels != null)
        {
            // Iterate through the pixel array and Check the pixel information that if it is a transparent color pixel and Change the pixel color to white
            for (int i = 0; i < pixels.Length; i++)
            {
                if (pixels[i] == rasterImg.TransparentColor.ToArgb())
                {
                    pixels[i] = Color.White.ToArgb();
                }
            }
            // Replace the pixel array into the image.
            rasterImg.SaveArgb32Pixels(img.Bounds, pixels);
        }
    }

    // Save the updated image to disk.
    if (rasterImg != null)
        rasterImg.Save(dataDir + "result.png");
}

File.Delete(dataDir + "result.png");

compress-png-images.cs

using Aspose.Imaging;
using Aspose.Imaging.Brushes;
using Aspose.Imaging.FileFormats.Bmp;
using Aspose.Imaging.FileFormats.Core.VectorPaths;
using Aspose.Imaging.FileFormats.Emf;
using Aspose.Imaging.FileFormats.Emf.Emf.Consts;
using Aspose.Imaging.FileFormats.Emf.Graphics;
using Aspose.Imaging.FileFormats.Gif;
using Aspose.Imaging.FileFormats.Gif.Blocks;
using Aspose.Imaging.FileFormats.Png;
using Aspose.Imaging.FileFormats.Tiff;
using Aspose.Imaging.FileFormats.Tiff.Enums;
using Aspose.Imaging.FileFormats.Tiff.PathResources;
using Aspose.Imaging.FileFormats.Webp;
using Aspose.Imaging.FileFormats.Wmf;
using Aspose.Imaging.FileFormats.Wmf.Graphics;
using Aspose.Imaging.ImageOptions;
using Aspose.Imaging.Sources;
using System;
using System.Collections.Generic;
using System.IO;
using System.Linq;

string templatesFolder = @"c:\Users\USER\Downloads\templates\";
string dataDir = templatesFolder;
string fileName = Path.Combine(dataDir, "template.tiff");


// Load an image from file (or stream)
using (Image image = Image.Load(dataDir + "template.png"))
{
    // Loop over possible CompressionLevel range
    for (int i = 0; i <= 9; i++)
    {
        // Create an instance of PngOptions for each resultant PNG, Set CompressionLevel and  Save result on disk
        PngOptions options = new PngOptions();
        options.CompressionLevel = i;
        image.Save(dataDir + i + "_out.png", options);
        File.Delete(dataDir + i + "_out.png");
    }
}

keep-transparency-when-indexing-png-image.cs

using Aspose.Imaging;
using Aspose.Imaging.Brushes;
using Aspose.Imaging.FileFormats.Bmp;
using Aspose.Imaging.FileFormats.Core.VectorPaths;
using Aspose.Imaging.FileFormats.Emf;
using Aspose.Imaging.FileFormats.Emf.Emf.Consts;
using Aspose.Imaging.FileFormats.Emf.Graphics;
using Aspose.Imaging.FileFormats.Gif;
using Aspose.Imaging.FileFormats.Gif.Blocks;
using Aspose.Imaging.FileFormats.Png;
using Aspose.Imaging.FileFormats.Tiff;
using Aspose.Imaging.FileFormats.Tiff.Enums;
using Aspose.Imaging.FileFormats.Tiff.PathResources;
using Aspose.Imaging.FileFormats.Webp;
using Aspose.Imaging.FileFormats.Wmf;
using Aspose.Imaging.FileFormats.Wmf.Graphics;
using Aspose.Imaging.ImageOptions;
using Aspose.Imaging.Sources;
using System;
using System.Collections.Generic;
using System.IO;
using System.Linq;

string templatesFolder = @"c:\Users\USER\Downloads\templates\";
string dataDir = templatesFolder;
string fileName = Path.Combine(dataDir, "template.tiff");

using (RasterImage image = (RasterImage)Image.Load(dataDir + "template.png"))
{
    PngOptions options = new PngOptions()
    {
        CompressionLevel = 9,
        ColorType = PngColorType.IndexedColor,
        Palette = ColorPaletteHelper.GetCloseTransparentImagePalette(image, 256),
        FilterType = PngFilterType.Avg,
    };

    image.Save(dataDir + "result.png", options);
}

File.Delete(dataDir + "result.png");

memory-strategy-optimization-png.cs

using Aspose.Imaging;
using Aspose.Imaging.FileFormats.Png;
using Aspose.Imaging.ImageOptions;
using System.IO;

string templatesFolder = @"c:\Users\USER\Downloads\templates\";
string dataDir = templatesFolder;

// Enabling the global memory usage optimization strategy.
// Setting a global memory limit of 50 megabytes 
Aspose.Imaging.MemoryManagement.Configuration.BufferSizeHint = 50;

using (var image = Image.Load(dataDir + "template.png"))
{
    image.Save(dataDir + "result.jpg", new Aspose.Imaging.ImageOptions.JpegOptions());
}

File.Delete(dataDir + "result.jpg");

set-resolution-in-png-images.cs

using Aspose.Imaging;
using Aspose.Imaging.Brushes;
using Aspose.Imaging.FileFormats.Bmp;
using Aspose.Imaging.FileFormats.Core.VectorPaths;
using Aspose.Imaging.FileFormats.Emf;
using Aspose.Imaging.FileFormats.Emf.Emf.Consts;
using Aspose.Imaging.FileFormats.Emf.Graphics;
using Aspose.Imaging.FileFormats.Gif;
using Aspose.Imaging.FileFormats.Gif.Blocks;
using Aspose.Imaging.FileFormats.Png;
using Aspose.Imaging.FileFormats.Tiff;
using Aspose.Imaging.FileFormats.Tiff.Enums;
using Aspose.Imaging.FileFormats.Tiff.PathResources;
using Aspose.Imaging.FileFormats.Webp;
using Aspose.Imaging.FileFormats.Wmf;
using Aspose.Imaging.FileFormats.Wmf.Graphics;
using Aspose.Imaging.ImageOptions;
using Aspose.Imaging.Sources;
using System;
using System.Collections.Generic;
using System.IO;
using System.Linq;

string templatesFolder = @"c:\Users\USER\Downloads\templates\";
string dataDir = templatesFolder;
string fileName = Path.Combine(dataDir, "template.tiff");


// Initialize variables to hold width & height values
int width = 0;
int height = 0;

// Initialize an array of type Color to hold the pixel data
Color[] pixels = null;

// Create an instance of RasterImage and load a BMP image
using (RasterImage raster = (RasterImage)Image.Load(dataDir + "template.png"))
{
    // Store the width & height in variables for later use
    width = raster.Width;
    height = raster.Height;

    // Load the pixels of RasterImage into the array of type Color
    pixels = raster.LoadPixels(new Rectangle(0, 0, width, height));
}

// Create & initialize an instance of PngImage while specifying size and PngColorType
using (PngImage png = new PngImage(width, height))
{
    // Save the previously loaded pixels on to the new PngImage
    png.SavePixels(new Rectangle(0, 0, width, height), pixels);

    // Create an instance of PngOptions, Set the horizontal & vertical resolutions and Save the result on disc
    PngOptions options = new PngOptions();
    options.ResolutionSettings = new ResolutionSetting(72, 96);
    png.Save(dataDir + "result.png", options);
}

File.Delete(dataDir + "result.png");

specify-bit-depth-in-png-image.cs

using Aspose.Imaging;
using Aspose.Imaging.Brushes;
using Aspose.Imaging.FileFormats.Bmp;
using Aspose.Imaging.FileFormats.Core.VectorPaths;
using Aspose.Imaging.FileFormats.Emf;
using Aspose.Imaging.FileFormats.Emf.Emf.Consts;
using Aspose.Imaging.FileFormats.Emf.Graphics;
using Aspose.Imaging.FileFormats.Gif;
using Aspose.Imaging.FileFormats.Gif.Blocks;
using Aspose.Imaging.FileFormats.Png;
using Aspose.Imaging.FileFormats.Tiff;
using Aspose.Imaging.FileFormats.Tiff.Enums;
using Aspose.Imaging.FileFormats.Tiff.PathResources;
using Aspose.Imaging.FileFormats.Webp;
using Aspose.Imaging.FileFormats.Wmf;
using Aspose.Imaging.FileFormats.Wmf.Graphics;
using Aspose.Imaging.ImageOptions;
using Aspose.Imaging.Sources;
using System;
using System.Collections.Generic;
using System.IO;
using System.Linq;

string templatesFolder = @"c:\Users\USER\Downloads\templates\";
string dataDir = templatesFolder;
string fileName = Path.Combine(dataDir, "template.tiff");


// Load an existing PNG image
using (PngImage png = (PngImage)Image.Load(dataDir + "template.png"))
{
    // Create an instance of PngOptions, Set the desired ColorType, BitDepth according to the specified ColorType and save image
    PngOptions options = new PngOptions();
    options.ColorType = PngColorType.Grayscale;
    options.BitDepth = 1;
    png.Save(dataDir + "result.png", options);
}

File.Delete(dataDir + "result.png");

specify-transparency-png.cs

using Aspose.Imaging;
using Aspose.Imaging.Brushes;
using Aspose.Imaging.FileFormats.Bmp;
using Aspose.Imaging.FileFormats.Core.VectorPaths;
using Aspose.Imaging.FileFormats.Emf;
using Aspose.Imaging.FileFormats.Emf.Emf.Consts;
using Aspose.Imaging.FileFormats.Emf.Graphics;
using Aspose.Imaging.FileFormats.Gif;
using Aspose.Imaging.FileFormats.Gif.Blocks;
using Aspose.Imaging.FileFormats.Png;
using Aspose.Imaging.FileFormats.Tiff;
using Aspose.Imaging.FileFormats.Tiff.Enums;
using Aspose.Imaging.FileFormats.Tiff.PathResources;
using Aspose.Imaging.FileFormats.Webp;
using Aspose.Imaging.FileFormats.Wmf;
using Aspose.Imaging.FileFormats.Wmf.Graphics;
using Aspose.Imaging.ImageOptions;
using Aspose.Imaging.Sources;
using System;
using System.Collections.Generic;
using System.IO;
using System.Linq;

string templatesFolder = @"c:\Users\USER\Downloads\templates\";
string dataDir = templatesFolder;
string fileName = Path.Combine(dataDir, "template.tiff");


// Initialize variables to hold width & height values
int width = 0;
int height = 0;

// Initialize an array of type Color to hold the pixel data
Color[] pixels = null;

// Create an instance of RasterImage and load a BMP image
using (RasterImage raster = (RasterImage)Image.Load(dataDir + "template.png"))
{
    // Store the width & height in variables for later use
    width = raster.Width;
    height = raster.Height;

    // Load the pixels of RasterImage into the array of type Color
    pixels = raster.LoadPixels(new Rectangle(0, 0, width, height));
}

// Create & initialize an instance of PngImage while specifying size and PngColorType
using (PngImage png = new PngImage(width, height, PngColorType.TruecolorWithAlpha))
{
    // Save the previously loaded pixels on to the new PngImage and Set TransparentColor property to specify which color to be rendered as transparent
    png.SavePixels(new Rectangle(0, 0, width, height), pixels);
    png.TransparentColor = Color.Black;
    png.HasTransparentColor = true;
    png.Save(dataDir + "result.jpg");
}

File.Delete(dataDir + "result.jpg");