Display synchronization signal generation apparatus in digital broadcast receiver and decoder

Abstract

A display synchronization signal generation apparatus and method is provided which makes it possible to display a stable image irrespective of changes in transmission speed of a received digital broadcast signal by generating a synchronization signal of an image to be displayed independently of a decoding period. A decoder suitable for the display synchronization signal generation apparatus is also provided. The decoder includes a clock signal generation unit, a pixel clock signal generation unit, and a synchronization signal generation unit. The clock signal generation unit generates a plurality of clock signals used for the decoding of the decoder based on a reference clock signal whose speed is controlled according to the transmission speed of a received broadcast signal. The pixel clock signal generation unit generates a display pixel clock signal based on a basic clock signal that is not dependent on the reference clock signal. The synchronization signal generation unit generates a horizontal synchronization signal and a vertical synchronization signal of the image to be displayed, in synchronization with the pixel clock signal generated by the pixel clock signal generation unit.