Non-photorealistic rendering for high dynamic range images

To mimic visual perception of human painters, a non-photorealistic rendering (NPR) method based on strokes is proposed for rendering high dynamic range images (HDR). It enables smooth guidance of the strokes generated in the rendering process on account of the improvement in computing the gradient values especially in the regions that have particularly high or low luminance values. Experimental results show that angles of gradient values obtained from HDR images have a reduction in the averaged error of up to 57.5% in comparison to that of conventional digital images. A partial experiment on incorporating HDR images into other NPR styles such as dithering shows the wide compatibility of HDR images in providing the source information for a NPR process.