Patent ID: 7019791
Filing Date: 2006-03-28
Classification: H04N

Abstract:
1. A television receiver which receives a digital video signal on which a digital audio signal is superimposed and a second audio signal input separately, shows an image obtained from the digital video signal on a display device, and can output audio obtained from the digital audio signal or the second audio signal through a loudspeaker, wherein: a sub-audio evaluation circuit evaluates quality of the second audio signal, an audio switching control circuit outputs a control signal indicating whether an error rate of the digital video or audio signal exceeds a threshold value or not, separation means separate the digital audio signal from the digital video signal, a switch which is connected to the audio switching control circuit and selects either the digital audio signal or the second audio signal separated by the separation means based on the control signal output from the audio switching control circuit and supplies to the loudspeaker; and the audio switching control circuit controls the switch to select the digital audio signal separated by the separation means when an error rate of the digital video or audio signal is smaller than a threshold value, and to select the second audio signal when the error rate exceeds the threshold value, the second audio signal is input by the sub-audio evaluation circuit and sound quality is judged good.