SPRUIL1D May 2019 – December 2024 DRA829J , DRA829J-Q1 , DRA829V , DRA829V-Q1 , TDA4VM , TDA4VM-Q1
In UYVY and NV12 mode, the pixel interpolation type can be set to bi-cubic interpolation for best quality or bilinear interpolation for faster performance.
As the coordinates ( hd,vd) calculated by the back-mapping function are not generally integer values, bi-cubic or bilinear interpolation is applied to the distorted pixels.
Depending on register configuration, bi-cubic or bilinear interpolation is used to interpolate the output Y pixels:
In the case of bi-cubic interpolation, the distorted pixel is interpolated from the 16 Y pixels in the 4 x 4 grid around the distorted location, as shown in Figure 6-111. Bi-cubic interpolation is used first along the horizontal direction, then the vertical direction.
Figure 6-111 LDC Bi-cubic Interpolation for YIf bi-linear interpolation is selected, the distorted pixel is interpolated from the four Y pixels in the 2 x 2 grid around the distorted location, as shown in Figure 6-112.
Figure 6-112 LDC Bi-linear Interpolation for YFor Cb and Cr components, simple bilinear interpolation is used. Each distorted pixel is interpolated from the four same-color pixels on the 2 x 2 grid around the distorted location. For UYVY data, the Cb/Cr grid is not square, but is 2x wider compared to the height. This is shown in Figure 6-113.
Figure 6-113 LDC Bilinear Interpolation for CB/Cr in UYVY and NV12 Format