Abstract: An audio amplifier receiving a digital input audio signal and generating an output audio signal for driving a speaker includes a digital input class D amplifier configured to receive the digital input audio signal and to generate the output audio signal. The digital input class D amplifier includes a first modulator configured to receive the digital input audio signal and to generate a quasi-digital signal in n-bit, and a class D modulator configured to receive the n-bit quasi-digital signal and to generate the output audio signal, the class D modulator implementing an analog feedback loop. In some embodiments, the class D modulator is implemented using a PWM modulator. In other embodiments, the PWM modulator incorporates enhanced features to improve the output noise characteristics.

Abstract: An audio amplifier receiving a digital input audio signal and generating an output audio signal for driving a speaker includes a digital input class D amplifier configured to receive the digital input audio signal and to generate the output audio signal. The digital input class D amplifier includes a first modulator configured to receive the digital input audio signal and to generate a quasi-digital signal in n-bit, and a class D modulator configured to receive the n-bit quasi-digital signal and to generate the output audio signal, the class D modulator implementing an analog feedback loop. In some embodiments, the class D modulator is implemented using a PWM modulator. In other embodiments, the PWM modulator incorporates enhanced features to improve the output noise characteristics.

Abstract: A system for the analysis of image data 48 that has been subject to one or more processing operations is described. The image data is displayed using a display palette 30 which maps pixel values PV to displayable appearances RGB, I. Under user control, a sub-section of the pixel values are mapped to enhanced displayable appearances so as to make small variations in the pixel values more visible. A palette scale 54 illustrating the mapping being performed by the palette 30 is displayed adjacent to the image 48 being analyzed. In addition, a graph 60 of the variation of pixel value along a given analysis line 62 is displayed to assist quantative analysis.

Abstract: Data to be processed is stored within data files 20. Associated with each data file 20 is a header file 18. The header files 18 store data specifying a wide range of attributes of the data within the data files 20. A user selects a particular signal processing function 14 that he desires to use and this then accesses one or mope selected data files 20 and associated header files 18. The selected signal processing tool 14 only needs a set of the attributes stored within the header files 18. The signal processing tool 14 reads those attributes it requires and then manipulates the data within the data file 20. The provision of this structure allows a wide range of signal processing function tools to be integrated into a single system which may also be simply expanded.