Abstract: A glitch-free clock switching circuit with clock loss tolerance and an operation method thereof and a corresponding glitch-free clock switching device are provided. The glitch-free clock switching circuit includes a first and a second stuck-status detection circuits, a first and a second reset synchronizers and a glitch-free switching core circuit. The glitch-free switching core circuit performs clock switching according to a clock switching signal to switch an output clock of the glitch-free clock switching circuit from an original clock source to a target clock source, where the original clock source and the target clock source represent one and the other of a first clock source and a second clock source, respectively; wherein the glitch-free clock switching circuit performs the clock switching based on a first synchronized reset signal and a second synchronized reset signal to provide the clock loss tolerance.

Abstract: A broadcast receiver includes a tuner circuit and a demodulator circuit. The tuner circuit tunes a radio frequency (RF) signal to output an intermediate frequency (IF) signal. The demodulator circuit demodulates the IF signal from the tuner circuit and outputs a command signal based on the quality of the IF signal, for changing a take over point (TOP) value, preset in the tuner circuit, at which one amplitude gain control (AGC) stopping and another taking over. A method for regulating a broadcast receiver is also disclosed herein.

Abstract: A sound-IF demodulator including a first demodulating unit and a second demodulating unit and a sound-IF detecting method thereof are provided. A sound de-matrix unit is adapted to generate a driving signal by de-matrixing outputs of the sound-IF demodulator. The first demodulating unit generates a first demodulated signal to the sound de-matrix unit by demodulating the first carrier signal. The second demodulating unit detects the signal quality of the sound signal and generates a second demodulated signal to the sound de-matrix unit and/or the first demodulating unit by demodulating the second carrier signal. When the second demodulating unit is idle, the second demodulating unit is programmed to select a corresponding standard among a plurality of predetermined standards for the sound signal according to the signal quality of the sound signal, so that the sound-IF demodulator is programmed to demodulate the sound signal in the corresponding standard.

Abstract: A method for determining a sound standard for an input sound signal includes the following steps. Firstly, the input sound signal is filtered to obtain a first filtered signal corresponding to a first frequency and a second filtered signal corresponding to a second frequency. Next, the first filtered signal is frequency-demodulated to obtain a first demodulated filtered signal, and whether the input sound signal contains a FM analog component corresponding to the first frequency is determined accordingly. Next, the second filtered signal is decoded according to a digital sound standard to obtain a bit stream. Then, the bit steam is interpreted according to the digital sound standard, and whether the input sound contains a digital component corresponding to the digital sound standard is determined accordingly. Then, whether the input sound signal matches one of known sound standards is determined based on the determined results above.

Abstract: An automatic gain control apparatus includes a first comparing module, a counting module, a second comparing module, and a control module. The first comparing module compares an input signal with a first threshold level and a second threshold level to generate a first compared output signal and a second compared output signal respectively. The counting module performs counting operations upon the first compared output signal and the second compared output signal to generate a first counting number and a second counting number respectively. The second comparing module compares the first counting number with a first threshold number to generate a first detection signal and compares the second counting number with a second threshold number to generate a second detection signal. The control module controls the gain of a radio frequency amplifier or an intermediate frequency amplifier according to the first detection signal and the second detection signal.

Abstract: A Radio Data System (RDS) decoder circuit determines a subcarrier frequency utilizing only a 57 kHz RDS signal of an FM broadcast signal. The RDS decoder includes a zero-intermediate frequency (zero-IF) FM demodulator, a first mixer, a low-pass filter (LPF) unit, a shaping filter unit, a carrier recovery circuit, a digitally controlled oscillator (DCO), a symbol timing recovery circuit, an integrate and dump circuit, a slicer 280, and a differential decoder. The carrier recovery circuit includes a phase error detector and a digital loop filter (DLF). The symbol timing recovery circuit includes a zero-crossing detector, a phase detector and loop filter unit, and a counter.

Abstract: A sound-IF demodulator including a first demodulating unit and a second demodulating unit and a sound-IF detecting method thereof are provided. A sound de-matrix unit is adapted to generate a driving signal by de-matrixing outputs of the sound-IF demodulator. The first demodulating unit generates a first demodulated signal to the sound de-matrix unit by demodulating the first carrier signal. The second demodulating unit detects the signal quality of the sound signal and generates a second demodulated signal to the sound de-matrix unit and/or the first demodulating unit by demodulating the second carrier signal. When the second demodulating unit is idle, the second demodulating unit is programmed to select a corresponding standard among a plurality of predetermined standards for the sound signal according to the signal quality of the sound signal, so that the sound-IF demodulator is programmed to demodulate the sound signal in the corresponding standard.

Abstract: An automatic gain control apparatus includes a first comparing module, a counting module, a second comparing module, and a control module. The first comparing module compares an input signal with a first threshold level and a second threshold level to generate a first compared output signal and a second compared output signal respectively. The counting module performs counting operations upon the first compared output signal and the second compared output signal to generate a first counting number and a second counting number respectively. The second comparing module compares the first counting number with a first threshold number to generate a first detection signal and compares the second counting number with a second threshold number to generate a second detection signal. The control module controls the gain of a radio frequency amplifier or an intermediate frequency amplifier according to the first detection signal and the second detection signal.

Abstract: A broadcast receiver includes a tuner circuit and a demodulator circuit. The tuner circuit tunes a radio frequency (RF) signal to output an intermediate frequency (IF) signal. The demodulator circuit demodulates the IF signal from the tuner circuit and outputs a command signal based on the quality of the IF signal, for changing a take over point (TOP) value, preset in the tuner circuit, at which one amplitude gain control (AGC) stopping and another taking over. A method for regulating a broadcast receiver is also disclosed herein.

Abstract: A method for determining a sound standard for an input sound signal includes the following steps. Firstly, the input sound signal is filtered to obtain a first filtered signal corresponding to a first frequency and a second filtered signal corresponding to a second frequency. Next, the first filtered signal is frequency-demodulated to obtain a first demodulated filtered signal, and whether the input sound signal contains a FM analog component corresponding to the first frequency is determined accordingly. Next, the second filtered signal is decoded according to a digital sound standard to obtain a bit stream. Then, the bit steam is interpreted according to the digital sound standard, and whether the input sound contains a digital component corresponding to the digital sound standard is determined accordingly. Then, whether the input sound signal matches one of known sound standards is determined based on the determined results above.

Abstract: A packing switching system and method is disclosed. A pipelined processor processes image pixels to generate a number of bit streams. Subsequently, a packing unit packs the bit streams into packets in a way that the bit stream or streams with minimum pixel order number are packed before other bit stream or streams.

Abstract: A Radio Data System (RDS) decoder circuit determines a subcarrier frequency utilizing only a 57 kHz RDS signal of an FM broadcast signal. The RDS decoder includes a zero-intermediate frequency (zero-IF) FM demodulator, a first mixer, a low-pass filter (LPF) unit, a shaping filter unit, a carrier recovery circuit, a digitally controlled oscillator (DCO), a symbol timing recovery circuit, an integrate and dump circuit, a slicer 280, and a differential decoder. The carrier recovery circuit includes a phase error detector and a digital loop filter (DLF). The symbol timing recovery circuit includes a zero-crossing detector, a phase detector and loop filter unit, and a counter.

Abstract: The present invention provides method of lossless data stream coding with high coding efficiency. The differential value of adjacent samples are calculated firstly and is coded by a VLC coding, the variable length coding. The VLC coding includes codes representing the quotient and remainder with a marker bit inserted in between. The divider is implicitly encoded and decoded with no code in the coded data stream. For pursuing high performance, at least two VLC encoder and VLD decoder are adopted to encode and decode the samples with one input from one location of the data stream and another input from another location of the data stream and the results saving from one location of the storage device and another result of data stream saving from another location of the storage device.