43.6.14.3 Vertical Scaler

ISC_VHXS_SS.YS indicates the vertical size minus one of the image in the system memory. ISC_VHXS_DS.YD contains the vertical size minus one of the output image.

ISC_VHXS_CTRL.VXSEN is used to activate the vertical scaler. The scaling factor is programmed in ISC_VXS_FACT.VFACT. The following equation calculates the vertical scaling factor (VFACT) value:

VFACT = round (\frac{2^{20} \times IMAGE_Y_SIZE_IN}{IMAGE_Y_SIZE_OUT})

The value VFACT is 24 bits wide (4-bit integer part, 20-bit fractional part), hence the vertical downsampling capacity is limited to 16.0.