Posts Tagged ‘spline’

Third-Order Texture Filtering using Linear Interpolation

January 12, 2013

A straightfoward implementation of bi- or tricubic texture filtering requires lots of texture lookups. As texture lookups are slow on current graphics hardware, reducing their number greatly improves the performance of high-order filtering kernels. In contrast, linear interpolation is relatively cheap as it is supported by the hardware. This fact has been exploited by Sigg and Hadwiger (2005) to make cubic interpolation much faster by performing a series of linear texture lookups. In this article, an in-depth explanation of their technique is given, starting with some general information on linear interpolation and approximation using cubic B-splines.