Abstract: In graphics processing data is received representing one or more vertices for a scene in a virtual space. A projection of the vertices onto a screen space of a display device is performed. A density of the vertices is adjusted for selected portions of the screen space, such that a lower density of vertices is present in selected portions of the screen space. Primitive assembly is performed on the vertices to generate a one or more primitives in screen space from the projection of the vertices onto the screen space. A finished frame is then generated by performing pixel processing to assign pixel values to the pixel or pixels that are part of the corresponding primitives. In some implementations, the finished frame can be stored in the memory or displayed on the display device.

Abstract: In graphics processing data is received representing one or more vertices for a scene in a virtual space. A projection of the vertices onto a screen space of a display device is performed. A density of the vertices is adjusted for selected portions of the screen space, such that a lower density of vertices is present in selected portions of the screen space. Primitive assembly is performed on the vertices to generate a one or more primitives in screen space from the projection of the vertices onto the screen space. A finished frame is then generated by performing pixel processing to assign pixel values to the pixel or pixels that are part of the corresponding primitives. In some implementations, the finished frame can be stored in the memory or displayed on the display device.

Abstract: Mode searching and early termination of a video picture may include determining the cost value of a simple intra-mode prediction of the video picture; determining the cost value of an inter-mode prediction of the video picture; determining a threshold value based on a given quantization parameter (QP); comparing the cost value of the simple intra-mode prediction to the sum of the cost value of the inter-mode prediction and the threshold value; and performing a mode-prediction of the video picture in accordance with the result obtained. Fast compression of variable length symbols may include receiving a variable length symbol with one or more tokens; combining the one or more tokens in the variable length symbol to form a token combination; and determining a bit representation of the token combination in correspondence to a probability threshold associated with the token combination.

Abstract: Prediction of and recovery from display buffer underflow are described. A first time delay for displaying a first group of one or more frames of a video picture stream located in an output frame buffer is calculated. A second time delay for displaying a second group of one or more frames in the picture stream is calculated. The second group directly follows the first group in the output buffer and is currently decoded by a decoder, but not yet deposited into the output frame buffer. A third time delay for decoding a third group of one or more frames in the picture stream is calculated. The third group directly follows the second group and is not yet decoded by the decoder. The decoder switches to or remains in a fast decoding mode if the sum of the first and second time delays is less than the third time delay.

Abstract: Mechanisms for performing decoding of context-adaptive binary arithmetic coding (CABAC) encoded data. The mechanisms receive, in a first single instruction multiple data (SIMD) vector register of the data processing system, CABAC encoded data of a bit stream. The CABAC encoded data includes a value to be decoded and bit stream state information. The mechanisms receive, in a second SIMD vector register of the data processing system, CABAC decoder context information. The mechanisms process the value, the bit stream state information, and the CABAC decoder context information in a non-recursive manner to generate a decoded value, updated bit stream state information, and updated CABAC decoder context information. The mechanisms store, in a third SIMD vector register, a result vector that combines the decoded value, updated bit stream state information, and updated CABAC decoder context information. The mechanisms use the decoded value to generate a video output on the data processing system.

Abstract: Mode searching and early termination of a video picture may include determining the cost value of a simple intra-mode prediction of the video picture; determining the cost value of an inter-mode prediction of the video picture; determining a threshold value based on a given quantization parameter (QP); comparing the cost value of the simple intra-mode prediction to the sum of the cost value of the inter-mode prediction and the threshold value; and performing a mode-prediction of the video picture in accordance with the result obtained. Fast compression of variable length symbols may include receiving a variable length symbol with one or more tokens; combining the one or more tokens in the variable length symbol to form a token combination; and determining a bit representation of the token combination in correspondence to a probability threshold associated with the token combination.

Abstract: Apparatus and Method for parallel digital picture encoding are disclosed. A digital picture is partitioned into two or more vertical sections. An encoder unit is selected to serve as a master and one or more encoder units are selected to serve as slaves. The total number of encoder units used equals the number of vertical sections. A mode search is performed on the two or more vertical sections on a row-by-row basis. Entropy coding is performed on the two or more vertical sections on a row-by-row basis. The entropy coding of each vertical section is performed in parallel such that each encoder unit performs entropy coding on its respective vertical section. De-blocking is performed on the two or more vertical sections in parallel on a row-by-row basis.

Abstract: Mechanisms for performing decoding of context-adaptive binary arithmetic coding (CABAC) encoded data. The mechanisms receive, in a first single instruction multiple data (SIMD) vector register of the data processing system, CABAC encoded data of a bit stream. The CABAC encoded data comprises a value to be decoded and bit stream state information. The mechanisms receive, in a second SIMD vector register of the data processing system, CABAC decoder context information. The mechanisms process the value, the bit stream state information, and the CABAC decoder context information in a non-recursive manner to generate a decoded value, updated bit stream state information, and updated CABAC decoder context information. The mechanisms store, in a third SIMD vector register, a result vector that combines the decoded value, updated bit stream state information, and updated CABAC decoder context information. The mechanisms use the decoded value to generate a video output on the data processing system.

Abstract: Prediction of and recovery from display buffer underflow are described. A first time delay for displaying a first group of one or more frames of a video picture stream located in an output frame buffer is calculated. A second time delay for displaying a second group of one or more frames in the picture stream is calculated. The second group directly follows the first group in the output buffer and is currently decoded by a decoder, but not yet deposited into the output frame buffer. A third time delay for decoding a third group of one or more frames in the picture stream is calculated. The third group directly follows the second group and is not yet decoded by the decoder. The decoder switches to or remains in a fast decoding mode if the sum of the first and second time delays is less than the third time delay.

Abstract: Apparatus and Method for parallel digital picture encoding are disclosed. A digital picture is partitioned into two or more vertical sections. An encoder unit is selected to serve as a master and one or more encoder units are selected to serve as slaves. The total number of encoder units used equals the number of vertical sections. A mode search is performed on the two or more vertical sections on a row-by-row basis. Entropy coding is performed on the two or more vertical sections on a row-by-row basis. The entropy coding of each vertical section is performed in parallel such that each encoder unit performs entropy coding on its respective vertical section. De-blocking is performed on the two or more vertical sections in parallel on a row-by-row basis.

Abstract: In the method and apparatus of the present invention, an editing system and method is provides that is sophisticated in features but easy to use. In one embodiment, the system includes multiple input sources, such as tape and live sources, at least one output recording device, at least one monitor, and a editing controller, such as a general purpose computer, which controls the input and output device. The controller further provides an innovative graphical user interface that intersperses video from the input devices along with control functions which the user can select using a mouse, keyboard or other input device.

Abstract: A system for simultaneous display of multiple video windows on a display device. This system includes a primary interface for receiving a primary video signal and a primary storage memory for storing data representing the primary video signal. Further, the present invention provides a plurality of secondary interface for receiving a plurality of secondary video signals and a secondary storage memory for storing data representing the plurality of secondary video signals. An output for selectively outputting the contents of a primary storage memory and the secondary storage memory to a display device so as to display video imagery represented by the primary video signal and secondary video signals in respective multiple video windows on the display device.

Abstract: A one pass adaptive bit rate control method. Data from a previous video field is used to calculate a quantizer scale factor for use in compressing a current video field. Large changes in compressed data size is used to detect scene changes. When a scene change is detected, a marker is inserted into the compressed data stream in place of the compressed field. An interpolated field is substituted during decompression for the scene change marker.

Abstract: A video signal processing circuit carries out error correction, error concealment and weighted mean processing sequentially on video signals reproduced by a video tape recorder. One and two dimensional error concealment modes are provided respectively utilizing sample data on the same line as erroneous sample data to be concealed, and sample data in peripheral and/or time displaced relation to the erroneous sample data. One of a plurality of error concealment modes is selected depending upon the state of error flags for the peripheral and/or time displaced sample data. In certain advantageous embodiments, original sample data for which a gray code has been set, is compared with error concealed data and the original sample data is output in place of the error concealed data where such comparison indicates that the difference between the two is within a predetermined acceptance threshold.

Abstract: An apparatus, including a lookup table memory, for gamma correcting a digital video signal based on the assumption that for small gamma, gamma correction is a linear function so that for a digital video input signal value x a gamma correction value d to be added to x can be calculated as a function of an opertor selected variable a according to the formulae:d=10.multidot.0.multidot.(x-x.sup.1.10)ord=10.multidot.9.multidot.(x-x.sup..90 ).