How can I control image smoothing?
Estimated Reading Time: 1 MinutesIn the Library, a function called PDPrefSetAntialiasLevel is provided to set the "smooth text" and "smooth images" global flags for subsequent rendering APIs. Can set smoothing in two ways, PDFPref APIs, and with PDPageDrawContentsToMemory APIs Their actual values should be:
- PDPrefAASmoothText=1
- PDPrefAASmoothLineArt=2
- PDPrefAASmoothImage=16 (decimal)
If you PDPref APIs, the smoothing preference setting will be used by the following APIs
- PDPageDrawContentsToWindow()
- PDPageDrawContentsToWindowEx()
- PDPageDrawContentsToWindowEx()
- PDDrawCosObjToWindow()
If you are using PDPageDrawContentsToMemory* it contains a Smooth argument value, which specifies the smoothing level using a combination of these flags:
- kPDPageDrawSmoothText
- kPDPageDrawSmoothLineArt
- kPDPageDrawSmoothImage
The Adobe PDF Library Java and .NET Interface also provides a sample program that demonstrates how to convert a PDF file to a set of image files. See the DocToImages sample in .NET (also available in Java and .NET Framework). This program offers an image smoothing option.