RasterImage.LoadPixels

RasterImage.LoadPixels method

Loads pixels.

public Color[] LoadPixels(Rectangle rectangle)

Parameter	Type	Description
rectangle	Rectangle	The rectangle to load pixels from.

Return Value

The loaded pixels array.

Examples

The following example shows how to load and process pixels of a raster image. For example, consider a problem of counting of fully transparent pixels of an image.

[C#]

using (Aspose.Imaging.Image image = Aspose.Imaging.Image.Load(@"c:\temp\alpha.png"))
{
    Aspose.Imaging.RasterImage rasterImage = (Aspose.Imaging.RasterImage)image;

    // Load pixels for the whole image. Any rectangular part of the image can be specified as a parameter of the Aspose.Imaging.RasterImage.LoadPixels method.
    Color[] pixels = rasterImage.LoadPixels(rasterImage.Bounds);

    int count = 0;
    foreach (Color pixel in pixels)
    {
        if (pixel.A == 0)
        {
            count++;
        }
    }

    System.Console.WriteLine("The number of fully transparent pixels is {0}", count);
    System.Console.WriteLine("The total number of pixels is {0}", image.Width * image.Height);
}

This example shows how to Loads Pixel information in an Array of Type Color, manipulates the array and set it back to the image. To perform these operations, this example creates a new Image file (in GIF format) uisng MemoryStream object.

[C#]

//Create an instance of MemoryStream
using (System.IO.MemoryStream stream = new System.IO.MemoryStream())
{
    //Create an instance of GifOptions and set its various properties including the Source property
    Aspose.Imaging.ImageOptions.GifOptions gifOptions = new Aspose.Imaging.ImageOptions.GifOptions();
    gifOptions.Source = new Aspose.Imaging.Sources.StreamSource(stream);

    //Create an instance of Image
    using (Aspose.Imaging.RasterImage image = (Aspose.Imaging.RasterImage)Aspose.Imaging.Image.Create(gifOptions, 500, 500))
    {
        //Get the pixels of image by specifying the area as image boundary
        Aspose.Imaging.Color[] pixels = image.LoadPixels(image.Bounds);

        //Loop over the Array and sets color of alrenative indexed pixel
        for (int index = 0; index < pixels.Length; index++)
        {
            if (index % 2 == 0)
            {
                //Set the indexed pixel color to yellow
                pixels[index] = Aspose.Imaging.Color.Yellow;
            }
            else
            {
                //Set the indexed pixel color to blue
                pixels[index] = Aspose.Imaging.Color.Blue;
            }
        }

        //Apply the pixel changes to the image
        image.SavePixels(image.Bounds, pixels);

        // save all changes.
        image.Save();
    }

    // Write MemoryStream to File
    using (System.IO.FileStream fileStream = new System.IO.FileStream(@"C:\temp\output.gif", System.IO.FileMode.Create))
    {
        stream.WriteTo(fileStream);
    }   
}

RasterImage.LoadPixels

RasterImage.LoadPixels method

Return Value

Examples

See Also