Class PngOptions
Class PngOptions
Namespace: Aspose.Imaging.ImageOptions
Assembly: Aspose.Imaging.dll (25.7.0)
Create high-quality Portable Network Graphics (PNG) raster images effortlessly with our API, offering customizable options for compression levels, bits per pixel depths, and alpha bits. Seamlessly process XMP metadata containers, ensuring comprehensive image metadata management, and empowering you to tailor PNG images to your exact specifications with ease.
public class PngOptions : ImageOptionsBase, IDisposable, IHasXmpData, IHasMetadata, ICloneableInheritance
object ← DisposableObject ← ImageOptionsBase ← PngOptions
Derived
Implements
IDisposable , IHasXmpData , IHasMetadata , ICloneable
Inherited Members
ImageOptionsBase.Clone() , ImageOptionsBase.ReleaseManagedResources() , ImageOptionsBase.KeepMetadata , ImageOptionsBase.XmpData , ImageOptionsBase.Source , ImageOptionsBase.Palette , ImageOptionsBase.ResolutionSettings , ImageOptionsBase.VectorRasterizationOptions , ImageOptionsBase.BufferSizeHint , ImageOptionsBase.MultiPageOptions , ImageOptionsBase.FullFrame , ImageOptionsBase.ProgressEventHandler , DisposableObject.Dispose() , DisposableObject.ReleaseManagedResources() , DisposableObject.ReleaseUnmanagedResources() , DisposableObject.VerifyNotDisposed() , DisposableObject.Disposed , object.GetType() , object.MemberwiseClone() , object.ToString() , object.Equals(object?) , object.Equals(object?, object?) , object.ReferenceEquals(object?, object?) , object.GetHashCode()
Examples
This example demonstrates the use of different classes from SaveOptions Namespace for export purposes. An image of type Gif is loaded into an instance of Image and then exported out to several formats.
string dir = "c:\\temp\\";
//Load an existing image (of type Gif) in an instance of Image class
using (Aspose.Imaging.Image image = Aspose.Imaging.Image.Load(dir + "sample.gif"))
{
//Export to BMP file format using the default options
image.Save(dir + "output.bmp", new Aspose.Imaging.ImageOptions.BmpOptions());
//Export to JPEG file format using the default options
image.Save(dir + "output.jpg", new Aspose.Imaging.ImageOptions.JpegOptions());
//Export to PNG file format using the default options
image.Save(dir + "output.png", new Aspose.Imaging.ImageOptions.PngOptions());
//Export to TIFF file format using the default options
image.Save(dir + "output.tif", new Aspose.Imaging.ImageOptions.TiffOptions(Aspose.Imaging.FileFormats.Tiff.Enums.TiffExpectedFormat.Default));
}The following example shows how to convert a multipage vector image to PNG format in general way without referencing to a particular image type.
string dir = "C:\\aspose.imaging\\net\\misc\\ImagingReleaseQATester\\Tests\\testdata\\2548";
string inputFilePath = System.IO.Path.Combine(dir, "Multipage.cdr");
string outputFilePath = System.IO.Path.Combine(dir, "Multipage.cdr.png");
Aspose.Imaging.ImageOptionsBase exportOptions = new Aspose.Imaging.ImageOptions.PngOptions();
using (Aspose.Imaging.Image image = Aspose.Imaging.Image.Load(inputFilePath))
{
exportOptions.MultiPageOptions = null;
// Export only first two pages. In fact, only one page will be rasterized because PNG is not a multi-page format.
Aspose.Imaging.IMultipageImage multipageImage = image as Aspose.Imaging.IMultipageImage;
if (multipageImage != null && (multipageImage.Pages != null && multipageImage.PageCount > 2))
{
exportOptions.MultiPageOptions = new Aspose.Imaging.ImageOptions.MultiPageOptions(new Aspose.Imaging.IntRange(0, 2));
}
if (image is Aspose.Imaging.VectorImage)
{
exportOptions.VectorRasterizationOptions = (Aspose.Imaging.ImageOptions.VectorRasterizationOptions)image.GetDefaultOptions(new object[] { Aspose.Imaging.Color.White, image.Width, image.Height });
exportOptions.VectorRasterizationOptions.TextRenderingHint = Aspose.Imaging.TextRenderingHint.SingleBitPerPixel;
exportOptions.VectorRasterizationOptions.SmoothingMode = Aspose.Imaging.SmoothingMode.None;
}
image.Save(outputFilePath, exportOptions);
}This example uses Graphics class to create primitive shapes on the Image surface. To demonstrate the operation, the example creates a new Image in PNG format and draw primitive shapes on Image surface using Draw methods exposed by Graphics class
//Creates an instance of FileStream
using (System.IO.FileStream stream = new System.IO.FileStream(@"C:\temp\output.png", System.IO.FileMode.Create))
{
//Create an instance of PngOptions and set its various properties
Aspose.Imaging.ImageOptions.PngOptions pngOptions = new Aspose.Imaging.ImageOptions.PngOptions();
//Set the Source for PngOptions
pngOptions.Source = new Aspose.Imaging.Sources.StreamSource(stream);
//Create an instance of Image
using (Aspose.Imaging.Image image = Aspose.Imaging.Image.Create(pngOptions, 500, 500))
{
//Create and initialize an instance of Graphics class
Aspose.Imaging.Graphics graphics = new Aspose.Imaging.Graphics(image);
//Clear Graphics surface
graphics.Clear(Aspose.Imaging.Color.Wheat);
//Draw an Arc by specifying the Pen object having Black color,
//a Rectangle surrounding the Arc, Start Angle and Sweep Angle
graphics.DrawArc(new Aspose.Imaging.Pen(Aspose.Imaging.Color.Black, 2), new Aspose.Imaging.Rectangle(200, 200, 100, 200), 0, 300);
//Draw a Bezier by specifying the Pen object having Blue color and co-ordinate Points.
graphics.DrawBezier(new Aspose.Imaging.Pen(Aspose.Imaging.Color.Blue, 2), new Aspose.Imaging.Point(250, 100), new Aspose.Imaging.Point(300, 30), new Aspose.Imaging.Point(450, 100), new Aspose.Imaging.Point(235, 25));
//Draw a Curve by specifying the Pen object having Green color and an array of Points
graphics.DrawCurve(new Aspose.Imaging.Pen(Aspose.Imaging.Color.Green, 2), new[] { new Aspose.Imaging.Point(100, 200), new Aspose.Imaging.Point(100, 350), new Aspose.Imaging.Point(200, 450) });
//Draw an Ellipse using the Pen object and a surrounding Rectangle
graphics.DrawEllipse(new Aspose.Imaging.Pen(Aspose.Imaging.Color.Yellow, 2), new Aspose.Imaging.Rectangle(300, 300, 100, 100));
//Draw a Line
graphics.DrawLine(new Aspose.Imaging.Pen(Aspose.Imaging.Color.Violet, 2), new Aspose.Imaging.Point(100, 100), new Aspose.Imaging.Point(200, 200));
//Draw a Pie segment
graphics.DrawPie(new Aspose.Imaging.Pen(Aspose.Imaging.Color.Silver, 2), new Aspose.Imaging.Rectangle(new Aspose.Imaging.Point(200, 20), new Aspose.Imaging.Size(200, 200)), 0, 45);
//Draw a Polygon by specifying the Pen object having Red color and an array of Points
graphics.DrawPolygon(new Aspose.Imaging.Pen(Aspose.Imaging.Color.Red, 2), new[] { new Aspose.Imaging.Point(20, 100), new Aspose.Imaging.Point(20, 200), new Aspose.Imaging.Point(220, 20) });
//Draw a Rectangle
graphics.DrawRectangle(new Aspose.Imaging.Pen(Aspose.Imaging.Color.Orange, 2), new Aspose.Imaging.Rectangle(new Aspose.Imaging.Point(250, 250), new Aspose.Imaging.Size(100, 100)));
//Create a SolidBrush object and set its various properties
Aspose.Imaging.Brushes.SolidBrush brush = new Aspose.Imaging.Brushes.SolidBrush();
brush.Color = Color.Purple;
brush.Opacity = 100;
//Draw a String using the SolidBrush object and Font, at specific Point
graphics.DrawString("This image is created by Aspose.Imaging API", new Aspose.Imaging.Font("Times New Roman", 16), brush, new Aspose.Imaging.PointF(50, 400));
// save all changes.
image.Save();
}
}Constructors
PngOptions()
Initializes a new instance of the Aspose.Imaging.ImageOptions.PngOptions class.
public PngOptions()PngOptions(PngOptions)
Initializes a new instance of the Aspose.Imaging.ImageOptions.PngOptions class.
public PngOptions(PngOptions pngOptions)Parameters
pngOptions PngOptions
The PNG options.
Fields
DefaultCompressionLevel
The default compression level.
public const PngCompressionLevel DefaultCompressionLevel = DeflateRecomendedField Value
Properties
BitDepth
Gets or sets the bit depth values in range of 1, 2, 4, 8, 16.
Mind the next limits:
Aspose.Imaging.FileFormats.Png.PngColorType.IndexedColor supports bit depth of 1, 2, 4, 8.
Aspose.Imaging.FileFormats.Png.PngColorType.Grayscale, Aspose.Imaging.FileFormats.Png.PngColorType.GrayscaleWithAlpha support bit depth of 8.
Aspose.Imaging.FileFormats.Png.PngColorType.Truecolor, Aspose.Imaging.FileFormats.Png.PngColorType.TruecolorWithAlpha support bit depth of 8, 16.
public byte BitDepth { get; set; }Property Value
Examples
This example shows how to create a PNG image with the specified options, fill it with a linear gradient colors and save it to a file.
string dir = "c:\\temp\\";
Aspose.Imaging.ImageOptions.PngOptions createOptions = new Aspose.Imaging.ImageOptions.PngOptions();
// The number of bits per color channel
createOptions.BitDepth = 8;
// Each pixel is a (red, green, blue) triple followed by the alpha component.
createOptions.ColorType = Imaging.FileFormats.Png.PngColorType.TruecolorWithAlpha;
// The maximum level of compression.
createOptions.CompressionLevel = 9;
// Usage of filters allows to compress continuous tonal images more effectively.
createOptions.FilterType = Aspose.Imaging.FileFormats.Png.PngFilterType.Sub;
// Use progressive loading
createOptions.Progressive = true;
// Create a PNG image with custom parameters.
using (Aspose.Imaging.FileFormats.Png.PngImage pngImage = new Aspose.Imaging.FileFormats.Png.PngImage(createOptions, 100, 100))
{
Aspose.Imaging.Brushes.LinearGradientBrush gradientBrush = new Aspose.Imaging.Brushes.LinearGradientBrush(
new Aspose.Imaging.Point(0, 0),
new Aspose.Imaging.Point(pngImage.Width, pngImage.Height),
Aspose.Imaging.Color.Blue,
Aspose.Imaging.Color.Transparent);
Aspose.Imaging.Graphics graphics = new Aspose.Imaging.Graphics(pngImage);
// Fill the image with a semi-transparent gradient.
graphics.FillRectangle(gradientBrush, pngImage.Bounds);
// Save to a file.
pngImage.Save(dir + "output.explicitoptions.png");
}The following example shows how to save an image to PNG format using various options.
string dir = "c:\\temp\\";
// Create a PNG image of 100x100 px.
// You can also load image of any supported format from a file or a stream.
using (Aspose.Imaging.FileFormats.Png.PngImage pngImage = new Aspose.Imaging.FileFormats.Png.PngImage(100, 100))
{
Aspose.Imaging.Brushes.LinearGradientBrush gradientBrush = new Aspose.Imaging.Brushes.LinearGradientBrush(
new Aspose.Imaging.Point(0, 0),
new Aspose.Imaging.Point(pngImage.Width, pngImage.Height),
Aspose.Imaging.Color.Blue,
Aspose.Imaging.Color.Transparent);
Aspose.Imaging.Graphics graphics = new Aspose.Imaging.Graphics(pngImage);
// Fill the image with the blue-transparent gradient.
graphics.FillRectangle(gradientBrush, pngImage.Bounds);
Aspose.Imaging.ImageOptions.PngOptions saveOptions = new Aspose.Imaging.ImageOptions.PngOptions();
// Progressive loading.
saveOptions.Progressive = true;
// Set the horizontal and vertical resolution to 96 pixels per inch.
saveOptions.ResolutionSettings = new Aspose.Imaging.ResolutionSetting(96.0, 96.0);
// Each pixel is a (red, green, blue) triple followed by alpha.
saveOptions.ColorType = Imaging.FileFormats.Png.PngColorType.TruecolorWithAlpha;
// Set the maximum level of compression.
saveOptions.CompressionLevel = 9;
// This is the best compression, but the slowest execution time.
// Adaptive filtering means that saving process will choose most sutable filter for each data row.
saveOptions.FilterType = Aspose.Imaging.FileFormats.Png.PngFilterType.Adaptive;
// The number of bits per channel.
saveOptions.BitDepth = 8;
// Save to a file.
pngImage.Save(dir + "output.png", saveOptions);
}ColorType
Gets or sets the type of the color.
public PngColorType ColorType { get; set; }Property Value
Examples
The following example shows how to compress a PNG image, using indexed color with best fit palette
// Loads png image
string sourceFilePath="OriginalRings.png";
string outputFilePath="OriginalRingsOutput.png";
using (Aspose.Imaging.Image image = Aspose.Imaging.Image.Load(sourceFilePath))
{
image.Save(outputFilePath, new Aspose.Imaging.ImageOptions.PngOptions()
{
Progressive = true,
// Use indexed color type
ColorType = Aspose.Imaging.FileFormats.Png.PngColorType.IndexedColor,
// Use maximal compression
CompressionLevel = 9,
// Get the closest 8-bit color palette which covers as many pixels as possible, so that a palettized image
// is almost visually indistinguishable from a non-palletized one.
Palette = Aspose.Imaging.ColorPaletteHelper.GetCloseImagePalette((Aspose.Imaging.RasterImage)image, 256, Aspose.Imaging.PaletteMiningMethod.Histogram)
});
}
// The output file size should be significantly reducedThis example shows how to create a PNG image with the specified options, fill it with a linear gradient colors and save it to a file.
string dir = "c:\\temp\\";
Aspose.Imaging.ImageOptions.PngOptions createOptions = new Aspose.Imaging.ImageOptions.PngOptions();
// The number of bits per color channel
createOptions.BitDepth = 8;
// Each pixel is a (red, green, blue) triple followed by the alpha component.
createOptions.ColorType = Imaging.FileFormats.Png.PngColorType.TruecolorWithAlpha;
// The maximum level of compression.
createOptions.CompressionLevel = 9;
// Usage of filters allows to compress continuous tonal images more effectively.
createOptions.FilterType = Aspose.Imaging.FileFormats.Png.PngFilterType.Sub;
// Use progressive loading
createOptions.Progressive = true;
// Create a PNG image with custom parameters.
using (Aspose.Imaging.FileFormats.Png.PngImage pngImage = new Aspose.Imaging.FileFormats.Png.PngImage(createOptions, 100, 100))
{
Aspose.Imaging.Brushes.LinearGradientBrush gradientBrush = new Aspose.Imaging.Brushes.LinearGradientBrush(
new Aspose.Imaging.Point(0, 0),
new Aspose.Imaging.Point(pngImage.Width, pngImage.Height),
Aspose.Imaging.Color.Blue,
Aspose.Imaging.Color.Transparent);
Aspose.Imaging.Graphics graphics = new Aspose.Imaging.Graphics(pngImage);
// Fill the image with a semi-transparent gradient.
graphics.FillRectangle(gradientBrush, pngImage.Bounds);
// Save to a file.
pngImage.Save(dir + "output.explicitoptions.png");
}The following example shows how to save an image to PNG format using various options.
string dir = "c:\\temp\\";
// Create a PNG image of 100x100 px.
// You can also load image of any supported format from a file or a stream.
using (Aspose.Imaging.FileFormats.Png.PngImage pngImage = new Aspose.Imaging.FileFormats.Png.PngImage(100, 100))
{
Aspose.Imaging.Brushes.LinearGradientBrush gradientBrush = new Aspose.Imaging.Brushes.LinearGradientBrush(
new Aspose.Imaging.Point(0, 0),
new Aspose.Imaging.Point(pngImage.Width, pngImage.Height),
Aspose.Imaging.Color.Blue,
Aspose.Imaging.Color.Transparent);
Aspose.Imaging.Graphics graphics = new Aspose.Imaging.Graphics(pngImage);
// Fill the image with the blue-transparent gradient.
graphics.FillRectangle(gradientBrush, pngImage.Bounds);
Aspose.Imaging.ImageOptions.PngOptions saveOptions = new Aspose.Imaging.ImageOptions.PngOptions();
// Progressive loading.
saveOptions.Progressive = true;
// Set the horizontal and vertical resolution to 96 pixels per inch.
saveOptions.ResolutionSettings = new Aspose.Imaging.ResolutionSetting(96.0, 96.0);
// Each pixel is a (red, green, blue) triple followed by alpha.
saveOptions.ColorType = Imaging.FileFormats.Png.PngColorType.TruecolorWithAlpha;
// Set the maximum level of compression.
saveOptions.CompressionLevel = 9;
// This is the best compression, but the slowest execution time.
// Adaptive filtering means that saving process will choose most sutable filter for each data row.
saveOptions.FilterType = Aspose.Imaging.FileFormats.Png.PngFilterType.Adaptive;
// The number of bits per channel.
saveOptions.BitDepth = 8;
// Save to a file.
pngImage.Save(dir + "output.png", saveOptions);
}CompressionLevel
Gets or sets the Aspose.Imaging.FileFormats.Png.PngImage compression level.
[Obsolete("This property is obsolete. Use PngCompressionLevel instead.", false)]
public int CompressionLevel { get; set; }Property Value
Examples
The following example shows how to compress a PNG image, using indexed color with best fit palette
// Loads png image
string sourceFilePath="OriginalRings.png";
string outputFilePath="OriginalRingsOutput.png";
using (Aspose.Imaging.Image image = Aspose.Imaging.Image.Load(sourceFilePath))
{
image.Save(outputFilePath, new Aspose.Imaging.ImageOptions.PngOptions()
{
Progressive = true,
// Use indexed color type
ColorType = Aspose.Imaging.FileFormats.Png.PngColorType.IndexedColor,
// Use maximal compression
CompressionLevel = 9,
// Get the closest 8-bit color palette which covers as many pixels as possible, so that a palettized image
// is almost visually indistinguishable from a non-palletized one.
Palette = Aspose.Imaging.ColorPaletteHelper.GetCloseImagePalette((Aspose.Imaging.RasterImage)image, 256, Aspose.Imaging.PaletteMiningMethod.Histogram)
});
}
// The output file size should be significantly reducedThis example shows how to create a PNG image with the specified options, fill it with a linear gradient colors and save it to a file.
string dir = "c:\\temp\\";
Aspose.Imaging.ImageOptions.PngOptions createOptions = new Aspose.Imaging.ImageOptions.PngOptions();
// The number of bits per color channel
createOptions.BitDepth = 8;
// Each pixel is a (red, green, blue) triple followed by the alpha component.
createOptions.ColorType = Imaging.FileFormats.Png.PngColorType.TruecolorWithAlpha;
// The maximum level of compression.
createOptions.CompressionLevel = 9;
// Usage of filters allows to compress continuous tonal images more effectively.
createOptions.FilterType = Aspose.Imaging.FileFormats.Png.PngFilterType.Sub;
// Use progressive loading
createOptions.Progressive = true;
// Create a PNG image with custom parameters.
using (Aspose.Imaging.FileFormats.Png.PngImage pngImage = new Aspose.Imaging.FileFormats.Png.PngImage(createOptions, 100, 100))
{
Aspose.Imaging.Brushes.LinearGradientBrush gradientBrush = new Aspose.Imaging.Brushes.LinearGradientBrush(
new Aspose.Imaging.Point(0, 0),
new Aspose.Imaging.Point(pngImage.Width, pngImage.Height),
Aspose.Imaging.Color.Blue,
Aspose.Imaging.Color.Transparent);
Aspose.Imaging.Graphics graphics = new Aspose.Imaging.Graphics(pngImage);
// Fill the image with a semi-transparent gradient.
graphics.FillRectangle(gradientBrush, pngImage.Bounds);
// Save to a file.
pngImage.Save(dir + "output.explicitoptions.png");
}The following example shows how to save an image to PNG format using various options.
string dir = "c:\\temp\\";
// Create a PNG image of 100x100 px.
// You can also load image of any supported format from a file or a stream.
using (Aspose.Imaging.FileFormats.Png.PngImage pngImage = new Aspose.Imaging.FileFormats.Png.PngImage(100, 100))
{
Aspose.Imaging.Brushes.LinearGradientBrush gradientBrush = new Aspose.Imaging.Brushes.LinearGradientBrush(
new Aspose.Imaging.Point(0, 0),
new Aspose.Imaging.Point(pngImage.Width, pngImage.Height),
Aspose.Imaging.Color.Blue,
Aspose.Imaging.Color.Transparent);
Aspose.Imaging.Graphics graphics = new Aspose.Imaging.Graphics(pngImage);
// Fill the image with the blue-transparent gradient.
graphics.FillRectangle(gradientBrush, pngImage.Bounds);
Aspose.Imaging.ImageOptions.PngOptions saveOptions = new Aspose.Imaging.ImageOptions.PngOptions();
// Progressive loading.
saveOptions.Progressive = true;
// Set the horizontal and vertical resolution to 96 pixels per inch.
saveOptions.ResolutionSettings = new Aspose.Imaging.ResolutionSetting(96.0, 96.0);
// Each pixel is a (red, green, blue) triple followed by alpha.
saveOptions.ColorType = Imaging.FileFormats.Png.PngColorType.TruecolorWithAlpha;
// Set the maximum level of compression.
saveOptions.CompressionLevel = 9;
// This is the best compression, but the slowest execution time.
// Adaptive filtering means that saving process will choose most sutable filter for each data row.
saveOptions.FilterType = Aspose.Imaging.FileFormats.Png.PngFilterType.Adaptive;
// The number of bits per channel.
saveOptions.BitDepth = 8;
// Save to a file.
pngImage.Save(dir + "output.png", saveOptions);
}FilterType
Gets or sets the filter type used during png file save process.
public PngFilterType FilterType { get; set; }Property Value
Examples
This example shows how to create a PNG image with the specified options, fill it with a linear gradient colors and save it to a file.
string dir = "c:\\temp\\";
Aspose.Imaging.ImageOptions.PngOptions createOptions = new Aspose.Imaging.ImageOptions.PngOptions();
// The number of bits per color channel
createOptions.BitDepth = 8;
// Each pixel is a (red, green, blue) triple followed by the alpha component.
createOptions.ColorType = Imaging.FileFormats.Png.PngColorType.TruecolorWithAlpha;
// The maximum level of compression.
createOptions.CompressionLevel = 9;
// Usage of filters allows to compress continuous tonal images more effectively.
createOptions.FilterType = Aspose.Imaging.FileFormats.Png.PngFilterType.Sub;
// Use progressive loading
createOptions.Progressive = true;
// Create a PNG image with custom parameters.
using (Aspose.Imaging.FileFormats.Png.PngImage pngImage = new Aspose.Imaging.FileFormats.Png.PngImage(createOptions, 100, 100))
{
Aspose.Imaging.Brushes.LinearGradientBrush gradientBrush = new Aspose.Imaging.Brushes.LinearGradientBrush(
new Aspose.Imaging.Point(0, 0),
new Aspose.Imaging.Point(pngImage.Width, pngImage.Height),
Aspose.Imaging.Color.Blue,
Aspose.Imaging.Color.Transparent);
Aspose.Imaging.Graphics graphics = new Aspose.Imaging.Graphics(pngImage);
// Fill the image with a semi-transparent gradient.
graphics.FillRectangle(gradientBrush, pngImage.Bounds);
// Save to a file.
pngImage.Save(dir + "output.explicitoptions.png");
}The following example shows how different filter types affect the size of the output PNG image.
Aspose.Imaging.FileFormats.Png.PngFilterType[] filterTypes = new Aspose.Imaging.FileFormats.Png.PngFilterType[]
{
Aspose.Imaging.FileFormats.Png.PngFilterType.None,
Aspose.Imaging.FileFormats.Png.PngFilterType.Up,
Aspose.Imaging.FileFormats.Png.PngFilterType.Sub,
Aspose.Imaging.FileFormats.Png.PngFilterType.Paeth,
Aspose.Imaging.FileFormats.Png.PngFilterType.Avg,
Aspose.Imaging.FileFormats.Png.PngFilterType.Adaptive,
};
foreach (Aspose.Imaging.FileFormats.Png.PngFilterType filterType in filterTypes)
{
Aspose.Imaging.ImageOptions.PngOptions options = new Aspose.Imaging.ImageOptions.PngOptions();
using (Aspose.Imaging.Image image = Image.Load("c:\\temp\\sample.png"))
{
// Set a filter type
options.FilterType = filterType;
using (System.IO.MemoryStream stream = new System.IO.MemoryStream())
{
image.Save(stream, options);
System.Console.WriteLine("The filter type is {0}, the output image size is {1} bytes.", filterType, stream.Length);
}
}
}
//The output may look like this:
//The filter type is None, the output image size is 116845 bytes.
//The filter type is Up, the output image size is 86360 bytes.
//The filter type is Sub, the output image size is 94907 bytes.
//The filter type is Paeth, the output image size is 86403 bytes.
//The filter type is Avg, the output image size is 89956 bytes.
//The filter type is Adaptive, the output image size is 97248 bytes.The following example shows how to save an image to PNG format using various options.
string dir = "c:\\temp\\";
// Create a PNG image of 100x100 px.
// You can also load image of any supported format from a file or a stream.
using (Aspose.Imaging.FileFormats.Png.PngImage pngImage = new Aspose.Imaging.FileFormats.Png.PngImage(100, 100))
{
Aspose.Imaging.Brushes.LinearGradientBrush gradientBrush = new Aspose.Imaging.Brushes.LinearGradientBrush(
new Aspose.Imaging.Point(0, 0),
new Aspose.Imaging.Point(pngImage.Width, pngImage.Height),
Aspose.Imaging.Color.Blue,
Aspose.Imaging.Color.Transparent);
Aspose.Imaging.Graphics graphics = new Aspose.Imaging.Graphics(pngImage);
// Fill the image with the blue-transparent gradient.
graphics.FillRectangle(gradientBrush, pngImage.Bounds);
Aspose.Imaging.ImageOptions.PngOptions saveOptions = new Aspose.Imaging.ImageOptions.PngOptions();
// Progressive loading.
saveOptions.Progressive = true;
// Set the horizontal and vertical resolution to 96 pixels per inch.
saveOptions.ResolutionSettings = new Aspose.Imaging.ResolutionSetting(96.0, 96.0);
// Each pixel is a (red, green, blue) triple followed by alpha.
saveOptions.ColorType = Imaging.FileFormats.Png.PngColorType.TruecolorWithAlpha;
// Set the maximum level of compression.
saveOptions.CompressionLevel = 9;
// This is the best compression, but the slowest execution time.
// Adaptive filtering means that saving process will choose most sutable filter for each data row.
saveOptions.FilterType = Aspose.Imaging.FileFormats.Png.PngFilterType.Adaptive;
// The number of bits per channel.
saveOptions.BitDepth = 8;
// Save to a file.
pngImage.Save(dir + "output.png", saveOptions);
}PngCompressionLevel
Gets or sets the Aspose.Imaging.FileFormats.Png.PngImage compression level.
public PngCompressionLevel PngCompressionLevel { get; set; }Property Value
Progressive
Gets or sets a value indicating whether a Aspose.Imaging.FileFormats.Png.PngImage is progressive.
public bool Progressive { get; set; }Property Value
Examples
The following example shows how to compress a PNG image, using indexed color with best fit palette
// Loads png image
string sourceFilePath="OriginalRings.png";
string outputFilePath="OriginalRingsOutput.png";
using (Aspose.Imaging.Image image = Aspose.Imaging.Image.Load(sourceFilePath))
{
image.Save(outputFilePath, new Aspose.Imaging.ImageOptions.PngOptions()
{
Progressive = true,
// Use indexed color type
ColorType = Aspose.Imaging.FileFormats.Png.PngColorType.IndexedColor,
// Use maximal compression
CompressionLevel = 9,
// Get the closest 8-bit color palette which covers as many pixels as possible, so that a palettized image
// is almost visually indistinguishable from a non-palletized one.
Palette = Aspose.Imaging.ColorPaletteHelper.GetCloseImagePalette((Aspose.Imaging.RasterImage)image, 256, Aspose.Imaging.PaletteMiningMethod.Histogram)
});
}
// The output file size should be significantly reducedThis example shows how to create a PNG image with the specified options, fill it with a linear gradient colors and save it to a file.
string dir = "c:\\temp\\";
Aspose.Imaging.ImageOptions.PngOptions createOptions = new Aspose.Imaging.ImageOptions.PngOptions();
// The number of bits per color channel
createOptions.BitDepth = 8;
// Each pixel is a (red, green, blue) triple followed by the alpha component.
createOptions.ColorType = Imaging.FileFormats.Png.PngColorType.TruecolorWithAlpha;
// The maximum level of compression.
createOptions.CompressionLevel = 9;
// Usage of filters allows to compress continuous tonal images more effectively.
createOptions.FilterType = Aspose.Imaging.FileFormats.Png.PngFilterType.Sub;
// Use progressive loading
createOptions.Progressive = true;
// Create a PNG image with custom parameters.
using (Aspose.Imaging.FileFormats.Png.PngImage pngImage = new Aspose.Imaging.FileFormats.Png.PngImage(createOptions, 100, 100))
{
Aspose.Imaging.Brushes.LinearGradientBrush gradientBrush = new Aspose.Imaging.Brushes.LinearGradientBrush(
new Aspose.Imaging.Point(0, 0),
new Aspose.Imaging.Point(pngImage.Width, pngImage.Height),
Aspose.Imaging.Color.Blue,
Aspose.Imaging.Color.Transparent);
Aspose.Imaging.Graphics graphics = new Aspose.Imaging.Graphics(pngImage);
// Fill the image with a semi-transparent gradient.
graphics.FillRectangle(gradientBrush, pngImage.Bounds);
// Save to a file.
pngImage.Save(dir + "output.explicitoptions.png");
}The following example shows how to save an image to PNG format using various options.
string dir = "c:\\temp\\";
// Create a PNG image of 100x100 px.
// You can also load image of any supported format from a file or a stream.
using (Aspose.Imaging.FileFormats.Png.PngImage pngImage = new Aspose.Imaging.FileFormats.Png.PngImage(100, 100))
{
Aspose.Imaging.Brushes.LinearGradientBrush gradientBrush = new Aspose.Imaging.Brushes.LinearGradientBrush(
new Aspose.Imaging.Point(0, 0),
new Aspose.Imaging.Point(pngImage.Width, pngImage.Height),
Aspose.Imaging.Color.Blue,
Aspose.Imaging.Color.Transparent);
Aspose.Imaging.Graphics graphics = new Aspose.Imaging.Graphics(pngImage);
// Fill the image with the blue-transparent gradient.
graphics.FillRectangle(gradientBrush, pngImage.Bounds);
Aspose.Imaging.ImageOptions.PngOptions saveOptions = new Aspose.Imaging.ImageOptions.PngOptions();
// Progressive loading.
saveOptions.Progressive = true;
// Set the horizontal and vertical resolution to 96 pixels per inch.
saveOptions.ResolutionSettings = new Aspose.Imaging.ResolutionSetting(96.0, 96.0);
// Each pixel is a (red, green, blue) triple followed by alpha.
saveOptions.ColorType = Imaging.FileFormats.Png.PngColorType.TruecolorWithAlpha;
// Set the maximum level of compression.
saveOptions.CompressionLevel = 9;
// This is the best compression, but the slowest execution time.
// Adaptive filtering means that saving process will choose most sutable filter for each data row.
saveOptions.FilterType = Aspose.Imaging.FileFormats.Png.PngFilterType.Adaptive;
// The number of bits per channel.
saveOptions.BitDepth = 8;
// Save to a file.
pngImage.Save(dir + "output.png", saveOptions);
}
