Abstract: The present invention is a method for MPEG compliance testing that designs test bit streams such that every frame of the expected decoded video is known. The test bit stream is generated, decoded and stored as an expected output decoded video. The test bit stream is fed to the device under test where it is decoded. Actual output video is compared with the expected decoded video on a frame-by-frame basis. The test results are indicated by discrepancies, which can be visually examined by human or by computer, through a comparison of the two videos. During generation of the test bit stream, for a given GOP structure, the subsequent P and B frames are determined by varying the selected testing MPEG parameter with the whole range of its possible values, while keeping other parameters constant.

Abstract: The present invention is a method for MPEG compliance testing that designs test bit streams such that every frame of the expected decoded video is known. The test bit stream is generated, decoded and stored as an expected output decoded video. The test bit stream is fed to the device under test where it is decoded. Actual output video is compared with the expected decoded video on a frame-by-frame basis. The test results are indicated by discrepancies, which can be visually examined by human or by computer, through a comparison of the two videos. During generation of the test bit stream, for a given GOP structure, the subsequent P and B frames are determined by varying the selected testing MPEG parameter with the whole range of its possible values, while keeping other parameters constant.

Abstract: The present invention is a method for MPEG compliance testing that designs test bit streams such that every frame of the expected decoded video is known. The test bit stream is generated, decoded and stored as an expected output decoded video. The test bit stream is fed to the device under test where it is decoded. Actual output video is compared with the expected decoded video on a frame-by-frame basis. The test results are indicated by discrepancies, which can be visually examined by human or by computer, through a comparison of the two videos. During generation of the test bit stream, for a given GOP structure, the subsequent P and B frames are determined by varying the selected testing MPEG parameter with the whole range of its possible values, while keeping other parameters constant.

Abstract: The present invention is a method for MPEG compliance testing that designs test bit streams such that every frame of the expected decoded video is known. The test bit stream is generated, decoded and stored as an expected output decoded video. The test bit stream is fed to the device under test where it is decoded. Actual output video is compared with the expected decoded video on a frame-by-frame basis. The test results are indicated by discrepancies, which can be visually examined by human or by computer, through a comparison of the two videos. During generation of the test bit stream, for a given GOP structure, the subsequent P and B frames are determined by varying the selected testing MPEG parameter with the whole range of its possible values, while keeping other parameters constant.

Abstract: A system and method for distributing high definition television (HDTV) and standard definition television (SDTV) signals via satellite is disclosed. At the transmission station an MPEG-2 video encoder compresses a video signal and a digital encoder encodes an audio signal. The compressed video and the encoded audio are coupled to PES packetizers, which generate video and audio packetized elementary data streams having PES headers and PES payloads. Within each PES header is a presentation time stamp (PTS), which is representative of the time at which the payload is to be displayed to the user. The packetized elementary data streams are multiplexed together by a transport multiplexer and repacketizer and broadcast to receiver stations, via satellite. The receiver stations receive the PES information and obtain the PTS. A receiver station multiplies the PTS by 300 and compares its local clock reference to that time.

Abstract: A video broadcast system is provided with an apparatus for processing a plurality of program signals corresponding to, for example, movies or other prerecorded programs, to selectively reduce the bandwidth required to transmit or broadcast the program signals. The signal processing apparatus includes a rate controller for generating a rate reduction factor based upon the data rates of the first and second program signals, a first channel processor coupled to receive the first program signal, and a second channel processor coupled to receive the second program signal. Each of the channel processors includes a data path for selectively reducing the bit rate of the program signals based upon the rate reduction factor.

Abstract: A statistical multiplexing apparatus for permanently recording a plurality of video signals on a video generator so that video programs represented by the video signals can be repeatedly broadcast is provided with a video analyzer for analyzing a first video signal and a second video signal and generating a first compression signal and a second compression signal, a first video encoder for encoding the first video signal at a variable rate determined by the first compression signal to form a first encoded video signal, a second video encoder for encoding the second video signal at a variable rate determined by the second compression signal to form a second encoded video signal, and a video generator for permanently recording the first and second encoded video signals so that the first and second encoded video signals can be repeatedly broadcast from the video generator.

Abstract: An apparatus for statistically multiplexing a plurality of video signals is provided with first and second complexity detectors which generate first and second complexity signals which relate to the complexity of first and second video signals, respectively, and first and second encoders for compressing the first and second video signals at variable compression rates to generate a first and second compressed video signals. The apparatus also includes a controller for controlling the variable compression rates of the encoders based on the complexity signal signals and a multiplexer coupled to receive the compressed video signals. The apparatus may be provided in a broadcasting system, such as a satellite is broadcasting system.

Abstract: An apparatus for statistically multiplexing a plurality of video signals is provided with a complexity detector, coupled to receive a pre-compressed video signal, for generating a complexity signal which relates to the complexity of the pre-compressed video signal, an encoder for compressing a non-compressed video signal at a variable compression rate to generate a compressed video signal, a controller for controlling the variable compression rate of the encoder based on the complexity signal, and a multiplexer coupled to receive the pre-compressed video signal and the compressed video signal. The apparatus may be provided in a broadcasting system, such as a satellite broadcasting system. The broadcast system may include a transmitter coupled to receive the video signals from the multiplexer, a satellite coupled to receive the video signals from the transmitter, a receiver for receiving video signals from the satellite, and one or more decoders connected to receive video signals from the receiver.

Abstract: A machine independent high resolution digital screen recorder provides high quality video displays with manageable storage capacity and bandwidth. The screen recorder includes an analog to digital frame grabber for converting the high resolution video signal that modulates a video display into RGB sequences of digital frames. A video compression unit separates the high and low variance portions of the digital frames, encodes them with respective lossy and lossless compression algorithms and stores them in a mass storage device.

Abstract: A method for specifying a video window's boundary coordinates directly from a multi-color video signal to separate the signals high and low variance components. The method converts the analog multi-color video signal into respective color sequences of digital frames and transforms them into another sequence of digital frames that represent the intensity of the multi-color video signal. The method generates difference frames between successive transformed intensity frames and computes a row activity measure and a column activity measure from at least one of the difference frames. The video window's approximate boundary coordinates are determined from said row and column activity measures.