摘要:
Implementing a two-dimensional inverse discrete cosine transform function includes executing two one-dimensional inverse discrete cosine transforming functions. Each of the one-dimensional functions is controlled to operate on a matrix of coefficients in either of two different directions.
摘要:
A sequence of input groups, each input group containing a number of input pixels, is received. A sequence of output frames is provided, where each output frame contains a number of output pixels to refresh a display screen. The pixels of each output frame include (1) a number of new pixels which are the input pixels of a respective input group, and (2) a number of old pixels which are the input pixels of a previous input group. The previous input group is one that's received previous to the respective input group.
摘要:
A chroma keying device is provided for switching between graphics images and video images. An input signal and a reference are compared to provide a switching signal for performing the switching between graphics and video. A switching signal is provided when the input signal color information indicates that the input signal represents a true black image. Thus, switching is triggered upon black in the chroma keying device of a present invention. The black level is determined when each of the red, blue and green inputs of the device receives substantially zero current. A very sensitive comparison is performed between these input lines and a reference voltage in order to detect this condition. In the chroma keying device of the present invention, this sensitive comparison is accomplished using matched diodes within a common integrated circuit.