Abstract: An image processing method and apparatus is described for processing a signal from a monochrome or color sensor that may be subject to pixel defects or blemishes. Without prior knowledge of any pixel defects, the processing method examines each pixel value and its neighboring pixel values. A number of tests are applied to the set of pixel values to determine whether the underlying pixel is defective. If the underlying pixel is determined to be defective, the pixel value is replaced by an estimate value derived from the values of its neighboring pixels. Otherwise, the pixel value remains intact.

Abstract: To determine the number of bits to encode a current audio frame, in accordance with a running average of the common scale factors for all preceding audio frames, a common scale factor for the-current frame is computed. The current frame is encoded using the computed common scale factor if the same falls within a defined range, and the number of bits required to so encode the frame also falls within a calculated range. If, the number of bits required to so encode the frame falls outside the calculated range, an energy level associated with the current frame and a running average of the energies of all previous frames is computed, which in turn, are used to compute a target bit rate. Thereafter, a common scale factor which results in coding of the current frame using a number of bits close to the target bit rate is obtained.

Abstract: To select the encoding mode of an audio signal in a multi-channel system, a level of energy of the audio signal associated with each channel is determined, which in turn is used to compute a first value. Next, a second value based on a degree of correlation of the signals of each channel is determined. If the first value is smaller than the second value, the audio signal is encoded using a first encoding mode. Next, a third value defined by the energy levels and a fourth value defined by the correlation are computed. If the first value is greater than the second value, and the third value is smaller than the fourth value, the audio signal is encoded using a second encoding mode. Otherwise the audio signal is encoded using a third encoding mode.

Abstract: To encode an audio signal xn, N samples of the audio signal is taken during each period of the signal (i.e., n varies from 0 to N-1) and are stored in a memory, such as a DRAM. The indices of the input samples (i.e., coefficients) are divided into T groups such that M of these coefficients each associated with a different one of the indices of each of the T groups may be read from the DRAM in a burst read operation. The M coefficients read during each burst operation are stored in a second memory in a burst write operation. Thereafter, each T time-domain coefficients whose indices belong to the same group are used to compute a first set of complex numbers ƒs which are subsequently used to encode the signal. Because the read and write operations are carried out using burst modes, the number of memory accesses is reduced, thereby improving efficiency and reducing cost.

Abstract: “An image processing system, in which bit shuffling is done in order to maintain image quality, stores digitized video data bits stream in a conventional memory, such as a DRAM. The image processing system is suitable for widely-used image compression standards that integrate various algorithms into a compression system, such as the standards specified in the Digital Video Standard (the DV-SD standard, or “Blue Book”). The image processing system receives a number of blocks associated with a first video frame and stores these blocks in the DRAM. The image processing system receives and stores blocks associated with a second video frame in the DRAM. The image processing system, processes the blocks of the first video frame while storing the blocks of the second video fame.

Abstract: Methods, apparatus, and systems are presented for arbitrating access to a shared resource involve deciding whether to grant access to the shared resource to at least one of a first plurality of devices in accordance with a first arbitration algorithm and deciding whether to grant access to the shared resource to at least one of a second plurality of devices in accordance with a second arbitration algorithm distinct from the first arbitration algorithm, if access to the shared resource is not granted to at least one of the first plurality of devices.

Abstract: A portion of the number of bits initially allocated for encoding some of the frames of a group of pictures (GOP) is accumulated in a bit bank and is subsequently used to encode other frames that may require a larger number of bits to encode than those initially allocated for these frames. Furthermore, when a scene change P frame is detected in a first GOP, a second GOP is formed. The second GOP includes the scene change P frame as well as the remaining unencoded frames of the original GOP. The P frame of the first GOP is changed to an I frame in the second GOP. Furthermore, the frame to be displayed after the I frame of the second GOP is also changed to a duplicate of the I frame of the second GOP.

Abstract: To detect color motion artifacts in a video frame, a motion-compensated color-distance value is compared against a threshold value. If the motion-compensated color-distance value is greater than or equal to the threshold value, color-motion artifacts are detected. The motion-compensated color-distance value is a sum of absolute values of the differences between corresponding pixel values of the video frame and a reference frame. To detect color motion artifacts in a video frame, in another embodiment, luminance and chrominance components of the intra-frame activity levels are compared against luminance and chrominance components of the inter-frame activity levels. If any of the components of the inter-frame activity levels is greater than the corresponding components of the intra-frame activity levels, color-motion artifacts are detected. To reduce color-motion artifacts, either a smaller quantization scale or intra-frame encoding is used to encode the data.

Abstract: To encode an unencoded block of a frame, a search window is defined within the frame. Each pixel disposed within the search window and disposed in the unencoded portion of the frame that is assigned a value. A difference is computed between the unencoded block and each possible block within the search window. The block having the smallest difference, together with this difference are used to encode the unencoded block.

Abstract: A method and apparatus for concatenating data words from a bitstream includes a scratch memory (802, 902) containing last words of unfinished blocks and left-aligned extra data words of finished blocks. A previous register (808, 908) holds one last word of an unfinished block. A next register (806, 906) holds a first of possibly many extra data words associated with the last word. A bit detector (810, 910), coupled to the previous register (808, 908) and the next register (806, 906), first concatenates the last word and the first extra data word and identifies selected bits for the detection of a valid code word. When no more valid code words can be found from the selected bits, and more data associated with the unfinished block exists, the first extra data word is moved to the previous register (808, 908) and a second extra data word is moved to the next register (806, 906). The first extra data word and the second extra data word are concatenated for the detection of another valid code word.

Abstract: New and improved methods and apparatus for run-length encoding video data. These techniques are especially suited to digital video applications, in which input to a video decoder is generated in order to determine run lengths and amplitudes. The implementations are suitable for widely-used image compression standards that integrate various algorithms into a compression system, such as the standards specified in the Digital Video Standard (the “Blue Book”).

Abstract: New and improved apparatus and methods for video encoding, for example, to efficiently and concurrently apply adaptive encoding techniques to convert analog data into digital formats, such as Digital Video (DV) format. A parallel system receives a block of video data and based on the computations and comparisons performed determines the best quantization factor for the block of video data. In an embodiment, the parallel system performs selected operations in parallel to save time and increase speed.

Abstract: New and improved methods and apparatus for code packing in a digital video system. Among others, a method of transferring a data block to a storage device is disclosed. The storage device can include a plurality of compartments. The method includes receiving a plurality of length values. Each length value can correspond to a data block from a plurality of data blocks. The method further includes filling a first compartment of the storage device with a portion of data from a first data block, searching the length values to identify one of the plurality of data blocks having a length value less than a threshold value, and filling a second compartment with a remaining portion of the data from the first data block. In one embodiment, the second compartment can correspond to the identified data block.

Abstract: New and improved methods and apparatus for concatenating data words from a bitstream. These techniques are especially suited to digital video applications, in which input to a video decoder is generated in order to determine run lengths and amplitudes. This implementation is suitable for widely-used image compression standards that integrate various algorithms into a compression system, such as the standards specified in the Digital Video Standard (the “Blue Book”).

Abstract: A memory control apparatus for block-matching motion estimation and an associated search pattern for processing video sequence in real-time are described in this disclosure. The motion estimation subsystem utilizes a set of memory banks to store a section of the reference picture used for computing the differences between an underlying block and a spatially shifted reference block. The memory control apparatus derives the memory addresses for storing the reference picture region in the memory banks in such a way that a row or a column of data from the reference block can be accessed in parallel without wait. The row- or column-data are then made available to the parallel computation unit for computing the block difference in a single processing cycle. An associated spiral search pattern that covers the whole search region is also described that minimizes the required data access and consequently saves power consumption.

Abstract: A method and apparatus for providing audio in a digital video system. Equations for a value n are provided for replacement into the conventional audio data shuffling equations. The equations for the value n provide for simple, efficient techniques to, in turn, calculate values for track number (TK), block number (BK), and data position number (DP). The values TK, BK, DP can be used in an address generation scheme to generate a page value and an offset value. The page value and the offset value for a particular sample of digital audio data, in part, determine the location of the sample in a memory storing the digital audio data. The present invention can be implemented for both four channel and two channel modes under both the NTSC and the PAL standards in accordance with specifications set forth in the Digital Video Standard (the “Blue Book”).

Abstract: New and improved apparatus and methods for video encoding, for example, to efficiently and concurrently encode video data into digital formats, such as Digital Video (DV) format. A pipelined system receives a block of video data and based on the computations and comparisons concurrently performed on the pixels within the block of video data determines which type of transformation is most appropriate for a given block of video data.

Abstract: New and improved apparatus and methods for encoding and decoding of a series of digital images. The throughput bit rate of conventional systems varies depending upon the complexity of the images. Applying apparatus and methods described herein, encoding and decoding of a series of digital images may be adjusted in an automated manner to achieve a constant throughput bit rate.

Abstract: An image compression apparatus for compressing image data provided to an input terminal and providing compressed data to an output terminal includes a 4×4 weighted digital cosine transformer (DCT) coupled to the input terminal and configured to convert the image data into weighted frequency data. A zigzag circuit is coupled to the DCT and configured to zigzag process the frequency data and generate create zigzag data. A Q-factor estimator is coupled to the DCT and configured to estimate the frequency data and generate a Q-factor. A DC coding circuit is coupled to the zigzag circuit and configured to code the zigzag data and generate a DC code. A quantization circuit is coupled to the zigzag circuit and the Q-factor estimator and configured to quantize the zigzag data based on the Q-factor and generate quantized data.