An apparatus for encoding a video includes: a predictor to predict a current block by using a plurality of prediction unit types and generate one or more predicted blocks; a subtracting unit to generate a residual block by the subtracting the predicted blocks from the current block; a transformer to generate a frequency transform block by transforming the residual block; a quantizer to generate a quantized frequency transform block by quantizing the frequency transform block; and an encoder to encode the quantized frequency transform block into a bitstream. When the quantized frequency transform block for one of the prediction unit types has all zero coefficients, the predictor terminates predicting the current block by using the remainder of the prediction unit types and determines the prediction unit type with said all zero coefficients as the prediction unit type for the current block.