[W8.1][C#]Windows 8.1 Canvas Image Conversion

[Windows Central Question]

I have developed one windows application that will generated an image from canvas.I am adding text data to canvas.Image will look clearly if there is less text,however if I add huge text content then generated Image will be blur.Can you suggest any technique for Clean Image generation from canvas.I am using fixed width for canvas and Converting an image to .png format.