Output Image Format
The ImageFormat class allows you to define the type of image created by the DynamicPDF Rasterizer. The easiest way to specify an image format is by using one of the ImageFormat class's static types. Alternatively, you can also instantiate an ImageFormat and set the properties directly.
The ImageFormat class also has the BmpImageFormat, GifImageFormat, JpegImageFormat, PngImageFormat, and TiffImageFormat child classes that offer formatting options specific to the respective image type.
ImageFormat Properties
The ImageFormat class has the following properties.
| AntiAliasing | Gets or Sets the AntiAliasing value. |
|---|---|
| Bmp | Gets a default BmpImageFormat class. |
| DefaultBlackThreshold | Gets or sets the default value of black threshold. |
| DefaultColorPalette | Gets or Sets the default color palette. |
| DefaultDitheringAlgorithm | Gets or Sets the default dithering algorithm. |
| DefaultDitheringPercent | Gets or Sets the default dithering percentage. |
| Gif | Gets a default GifImageFormat class. |
| Jpeg | Gets a default JpegImageFormat class. |
| Png | Gets a default PngImageFormat class. |
| TiffWithCcitGroup3 | Gets a default TiffImageFormat class with CCIT Group 3 compression specified. |
| TiffWithCcitGroup4 | Gets a default TiffImageFormat class with CCIT Group 4 compression specified. |
| TiffWithLzw | Gets a default TiffImageFormat class with JPEG compression specified. |
ImageFormat Static Types
ImageFormat defines several static image types for quickly specifying the type of image to output. These static members significantly simplify your code when customization is not required.
- ImageFormat.Bmp
- ImageFormat.Gif
- ImageFormat.Jpeg
- ImageFormat.Png
- ImageFormat.TiffWithCcitGroup3
- ImageFormat.TiffWithCcitGroup4
- ImageFormat.TiffWithLzw
The following example illustrates rasterizing a PDF document into a PNG image using the static PNG ImageFormat.Png.
PdfRasterizer rasterizer = new PdfRasterizer("DocumentA.pdf");
rasterizer.Draw("pdf-to-png-output.gif", ImageFormat.Png, ImageSize.Dpi300);
Dim rasterizer As New PdfRasterizer("DocumentA.pdf")
rasterizer.Draw("pdf-to-png-output.gif", ImageFormat.Png, ImageSize.Dpi300)
Setting ImageFormat Properties
You can also instantiate the ImageFormat type needed and set its properties directly by instantiating one of the following classes and passing it into the PdfRasterizer class Draw method.
- ceTe.DynamicPDF.Rasterizer.BmpImageFormat
- ceTe.DynamicPDF.Rasterizer.GifImageFormat
- ceTe.DynamicPDF.Rasterizer.JpegImageFormat
- ceTe.DynamicPDF.Rasterizer.PngImageFormat
- ceTe.DynamicPDF.Rasterizer.TiffImageFormat
The following example illustrates rasterizing a PDF document into a PNG that includes transparency.
PdfRasterizer rasterizer = new PdfRasterizer("pdf-with-transparency.pdf");
PngImageFormat png = new PngImageFormat(PngColorFormat.RgbA);
rasterizer.Draw("pdf-to-png-transparent-output.png",png, ImageSize.Dpi300);
Dim rasterizer As New PdfRasterizer("pdf-with-transparency.pdf")
Dim png As New PngImageFormat(PngColorFormat.RgbA)
rasterizer.Draw("pdf-to-png-transparent-output.png", png, ImageSize.Dpi300)