Abstract: A method and apparatus for image data compression is disclosed. According to one embodiment, image data may be received at a digital video camera having an encoder and a transmitter. The encoder of the digital video camera may be used to compress the image data into an encoded information stream capable of carrying at least 8.5 frames/second in which no frame depends on a previous frame by performing intra frame encoding. The transmitter may transmit the encoded information stream from the digital video camera to a computer system via a Universal Serial Bus (USB) while consuming no more than approximately 4 Mbits/second of USB bandwidth.

Abstract: A method and apparatus for video conferencing is disclosed. According to one embodiment, a Universal Serial Bus (USB) enabled digital video camera may output an encoded information stream. The USB-enabled digital video camera including an encoder may compress image data received by the USB-enabled digital video camera during a real-time video conference to produce the encoded information stream in which no frame of the encoded information stream may depend on a previous frame by performing intra frame encoding. A computer system coupled to the USB-enabled digital video camera via a USB may be used to decode the encoded information stream and to transmit the image data to one or more other computer systems as part of a video conferencing data stream.

Abstract: A method and apparatus for image data compression is disclosed. According to one embodiment, image data may be received at a digital video camera having an encoder and a transmitter. The encoder of the digital video camera may be used to compress the image data into an encoded information stream capable of carrying at least 8.5 frames/second in which no frame depends on a previous frame by performing intra frame encoding. The transmitter may transmit the encoded information stream from the digital video camera to a computer system via a Universal Serial Bus (USB) while consuming no more than approximately 4 Mbits/second of USB bandwidth.

Abstract: A method and apparatus for encoding a digital image is disclosed. A difference is calculated between a first sample from a current scan line and a corresponding second sample from a previous scan line. A quantization table level is selected from a quantization table that includes at least one level, and information identifying the selected level is placed into an information stream. A quantizer is selected from the quantization table level based on the calculated difference and information corresponding to the selected quantizer is place into the information stream.

Abstract: A method and apparatus for video conferencing is disclosed. According to one embodiment, a Universal Serial Bus (USB) enabled digital video camera may output an encoded information stream. The USB-enabled digital video camera including an encoder may compress image data received by the USB-enabled digital video camera during a real-time video conference to produce the encoded information stream in which no frame of the encoded information stream may depend on a previous frame by performing intra frame encoding. A computer system coupled to the USB-enabled digital video camera via a USB may be used to decode the encoded information stream and to transmit the image data to one or more other computer systems as part of a video conferencing data stream.

Abstract: A method and apparatus for encoding a digital image is disclosed. A difference is calculated between a first sample from a current scan line and a corresponding second sample from a previous scan line. A quantization table level is selected from a quantization table that includes at least one level, and information identifying the selected level is placed into an information stream. A quantizer is selected from the quantization table level based on the calculated difference and information corresponding to the selected quantizer is place into the information stream.

Abstract: A method and apparatus for encoding a digital image is disclosed. A differences is calculated between a first sample from a current scan line and a corresponding second sample from a previous scan line. A quantization table level is selected from a quantization table that at least one level, and information identifying the selected level is placed into an information stream. A quantizer is selected from the quantization table level based on the calculated difference and information corresponding to the selected quantizer is placed into the information stream.

Abstract: A circuit for analog chroma keying on color data permits display of graphics, generated from a computer system, and video on an output display. The analog chroma keying circuit receives the graphics signals and the video signals, wherein the graphics signals include color data to designate a color key. The analog chroma keying circuit includes a plurality of digital to analog converters that generate a plurality of color key limits for defining a range to detect the color data denoting the color key. The analog chroma keying circuit also includes a plurality of comparators coupled to receive the graphics signals and the color key limits for each primary color. The plurality of comparators generate a key on indicator when the graphics signals fall within the color key limits.