RasterImage.GetArgb32Pixel
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[
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]RasterImage.GetArgb32Pixel method
Gets an image 32-bit ARGB pixel.
public int GetArgb32Pixel(int x, int y)
Parameter | Type | Description |
---|---|---|
x | Int32 | The pixel x location. |
y | Int32 | The pixel y location. |
Return Value
The 32-bit ARGB pixel for the specified location.
Examples
The following example loads a raster image and obtains the color of an arbitrary pixel represented as a 32-bit integer value.
[C#]
using (Aspose.Imaging.Image image = Aspose.Imaging.Image.Load(@"c:\temp\sample.png"))
{
Aspose.Imaging.RasterImage rasterImage = (Aspose.Imaging.RasterImage)image;
// Get an integer representation of the color of the top-left pixel of the image.
int color = rasterImage.GetArgb32Pixel(0, 0);
// To obtain the values of the individual color components, shift the color value by a corresponding number of bits
int alpha = (color >> 24) & 0xff;
int red = (color >> 16) & 0xff;
int green = (color >> 8) & 0xff;
int blue = (color >> 0) & 0xff;
System.Console.WriteLine("The color of the pixel(0,0) is A={0},R={1},G={2},B={3}", alpha, red, green, blue);
}
The following example shows how image caching affects performance. In general case, reading cached data is performed faster than reading non-cached data.
[C#]
string dir = "c:\\temp\\";
// Load an image from a PNG file.
using (Aspose.Imaging.Image image = Aspose.Imaging.Image.Load(dir + "sample.png"))
{
// Cache all pixel data so that no additional data loading will be performed from the underlying data stream
image.CacheData();
System.Diagnostics.Stopwatch stopwatch = new System.Diagnostics.Stopwatch();
stopwatch.Start();
// Reading all pixels is pretty fast.
Aspose.Imaging.RasterImage rasterImage = (Aspose.Imaging.RasterImage)image;
for (int y = 0; y < image.Height; y++)
{
for (int x = 0; x < image.Width; x++)
{
int color = rasterImage.GetArgb32Pixel(x, y);
}
}
stopwatch.Stop();
System.Console.WriteLine("Reading all cached pixels took {0} ms.", stopwatch.ElapsedMilliseconds);
}
// Load an image from a PNG file
using (Aspose.Imaging.Image image = Aspose.Imaging.Image.Load(dir + "sample.png"))
{
System.Diagnostics.Stopwatch stopwatch = new System.Diagnostics.Stopwatch();
stopwatch.Start();
// Reading all pixels is not as fast as when caching
Aspose.Imaging.RasterImage rasterImage = (Aspose.Imaging.RasterImage)image;
for (int y = 0; y < image.Height; y++)
{
for (int x = 0; x < image.Width; x++)
{
int color = rasterImage.GetArgb32Pixel(x, y);
}
}
stopwatch.Stop();
System.Console.WriteLine("Reading all pixels without preliminary caching took {0} ms.", stopwatch.ElapsedMilliseconds);
}
// The output may look like this:
// Reading all cached pixels took 1500 ms.
// Reading all pixels without preliminary caching took 150000 ms.
See Also
- class RasterImage
- namespace Aspose.Imaging
- assembly Aspose.Imaging