Abstract: A video encoder includes an entropy encoder that computes a predicted motion vector (PMV) for each of a plurality of macroblocks in a video frame based on motion vectors of multiple other macroblocks. The video encoder also includes a motion estimator that determines a predicted motion vector for a given macroblock by reusing, as the predicted motion vector for the given macroblock, only the PMV computed by the entropy encoder for a macroblock immediately on top of the given macroblock.

Abstract: A method of improving the perceptual video quality of video sequences containing black bars. Horizontal or vertical black bars caused by a missmatch between the aspect ratio of the encoded video and the display device. The presence of black bars is detected, and the encoding process is adjusted to eliminate visual depredation of the reproduced video.

Abstract: Techniques for efficiently performing full and scaled transforms on data received via full and scaled interfaces, respectively, are described. A full transform is a transform that implements the complete mathematical description of the transform. A full transform operates on or provides full transform coefficients. A scaled transform is a transform that operates on or provides scaled transform coefficients, which are scaled versions of the full transform coefficients. The scaled transform may have lower computational complexity whereas the full transform may be simpler to use by applications. The full and scaled transforms may be for a 2D IDCT, which may be implemented in a separable manner with 1D IDCTs. The full and scaled transforms may also be for a 2D DCT, which may be implemented in a separable manner with 1D DCTs. The 1D IDCTs and 1D DCTs may be implemented in a computationally efficient manner.

Abstract: A method for encoding a picture in a video sequence is provided that includes determining the current encoded size of the picture after coding a plurality of macroblocks in the picture, determining that encoding remaining macroblocks in the picture may cause the encoded size of the picture to exceed a maximum encoded picture size, computing a quantization scale responsive to the determining, wherein the quantization scale is computed such that the estimated encoded size of the remaining macroblocks if the remaining macroblocks are quantized with the quantization scale does not exceed the difference between the maximum encoded picture size and the current encoded picture size, and quantizing at least one of the remaining macroblocks with the new quantization scale.

Abstract: A method for intra-prediction estimation is provided that includes determining a best intra-prediction mode for a block of samples, wherein at least some of the neighboring samples used for intra-prediction estimation include approximate reconstructed samples, applying approximate reconstruction to the block of samples using the best intra-prediction mode to generate a block of approximate reconstructed samples, and storing the block of approximate reconstructed samples for use in intra-prediction estimation of other blocks of samples.

Abstract: A method and system for bit rate control during encoding of multimedia data are disclosed. A change in complexity of a multimedia picture relative to complexity associated with one or more multimedia pictures in a multimedia sequence is determined. A complexity associated with a multimedia picture is determined based on number of bits and an average quantization associated with the multimedia picture. A bit rate is adjusted for encoding the multimedia picture based on the change in complexity of the multimedia picture. The bit rate is increased on determining an increase in complexity of the multimedia picture and is decreased on determining a decrease in complexity of the multimedia picture. Utilization of additional bits during the increase in the bit rate and saving of bits during the decrease in the bit rate are compensated during adjusting of bit rates for encoding subsequent multimedia pictures in the multimedia sequence.

Abstract: A video encoder includes an entropy encoder that computes a predicted motion vector (PMV) for each of a plurality of macroblocks in a video frame based on motion vectors of multiple other macroblocks. The video encoder also includes a motion estimator that determines a predicted motion vector for a given macroblock by reusing, as the predicted motion vector for the given macroblock, only the PMV computed by the entropy encoder for a macroblock immediately on top of the given macroblock.

Abstract: A video encoder includes a buffer, a DMA engine, a motion estimator and a motion compensator. The buffer includes four pages where macroblocks are stored. The motion estimator generates a motion vector for a given macroblock. The motion compensator applies the motion vectors generated by the motion estimator to a previously encoded frame. Each of the four pages is concurrently accessed by one of the motion estimator, the motion compensator, and a channel of the DMA engine. Simultaneously the motion compensator accesses one page of the buffer containing a first set of macroblocks, the motion estimator accesses a second page of the buffer containing a second set of macroblocks, a first DMA engine channel writes a different set of macroblocks to a third page of the buffer and a second DMA engine channel writes another set of macroblocks to a fourth page of the buffer.

Abstract: A video encoder including a first buffer containing a plurality of data values defining a macroblock of pixels of a video frame. The video encoder also includes a second buffer and an entropy encoder coupled to the first and second buffers and configured to encode a macroblock based on another macroblock. The entropy encoder identifies a subset of the data values from the first buffer defining a given macroblock and copies the identified subset to the second buffer, the subset of data values being just those data values used by the entropy encoder when subsequently encoding another macroblock.

Abstract: A method for encoding a picture in a video sequence is provided that includes determining the current encoded size of the picture after coding a plurality of macroblocks in the picture, determining that encoding remaining macroblocks in the picture may cause the encoded size of the picture to exceed a maximum encoded picture size, computing a quantization scale responsive to the determining, wherein the quantization scale is computed such that the estimated encoded size of the remaining macroblocks if the remaining macroblocks are quantized with the quantization scale does not exceed the difference between the maximum encoded picture size and the current encoded picture size, and quantizing at least one of the remaining macroblocks with the new quantization scale.

Abstract: A method of encoding a block of pixels in a digital video sequence that includes computing an average texture measure for a plurality of blocks of pixels encoded prior to the block of pixels, computing a texture measure for the block of pixels, computing a block quantization step size for the block of pixels as the product of a quantization step size selected for a sequence of blocks of pixels comprising the block of pixels and a multiplication factor selected from a set of multiplication factors based on a ratio of the texture measure and the average texture measure, and quantizing the block of pixels using the block quantization step size.

Abstract: A method of encoding an image frame in a video encoding system. The image frame has a region of interest (ROI) and a non region of interest (non-ROI). In the method, quantization scale for the image frame based on rate control information is determined. ROI statistics based on residual energy of the ROI and non-ROI is then calculated. Quantization scale for the image frame based on ROI priorities and ROI statistics is calculated. Further, quantization scales for ROI and non-ROI based on ROI priorities are determined.

Abstract: Method and system to improve the performance of a video encoder. The method includes processing an initial video signal in a front-end image pre-processor to obtain a processed video signal and processor information respecting the signal, providing the processed video signal and the processor information to a video encoder, and encoding the video signal in the video encoder according to the processor information to provide an encoded video signal for storage. The system includes a video pre-processor connectable to receive an initial video signal. The video encoder in communication with the video pre-processor receives a processed video signal and a processor information. A storage medium in communication with the video encoder stores an encoded video signal.

Abstract: A video encoder receives a minimum number of bits (MIN) and a maximum number of bits (MAX) to be used to encode a segment of a sequence of image frames, the segment including a set of pictures contained in the sequence of image frames. The video encoder encodes the set of pictures using a total number of bits greater than the minimum number of bits (MIN), and not exceeding the maximum number of bits (MAX). Thus, the transmission bit-rate of the video encoder can be constrained to lie within a maximum and minimum rate. In an embodiment, the constraints are enforced over relatively short time intervals.

Abstract: In an apparatus and method, time-varying signals are processed and encoded via a frequency domain linear prediction (FDLP) scheme to arrive at an all-pole model. Residual signals resulted from the scheme are estimated. Quantized values of the all-pole model and the residual signals are packetized as encoded signals suitable for transmission or storage. To reconstruct the time-varying signals, the encoded signals are decoded. The decoding process is basically the reverse of the encoding process.

Abstract: Techniques for efficiently performing full and scaled transforms on data received via full and scaled interfaces, respectively, are described. A full transform is a transform that implements the complete mathematical description of the transform. A full transform operates on or provides full transform coefficients. A scaled transform is a transform that operates on or provides scaled transform coefficients, which are scaled versions of the full transform coefficients. The scaled transform may have lower computational complexity whereas the full transform may be simpler to use by applications. The full and scaled transforms may be for a 2D IDCT, which may be implemented in a separable manner with 1D IDCTs. The full and scaled transforms may also be for a 2D DCT, which may be implemented in a separable manner with ID DCTs. The 1D IDCTs and 1D DCTs may be implemented in a computationally efficient manner.

Abstract: Techniques for efficiently performing computation for signal and data processing are described. For multiplication-free processing, a series of intermediate values is generated based on an input value for data to be processed. At least one intermediate value in the series is generated based on at least one other intermediate value in the series. One intermediate value in the series is provided as an output value for a multiplication of the input value with a constant value. The constant value may be an integer constant, a rational constant, or an irrational constant. An irrational constant may be approximated with a rational dyadic constant having an integer numerator and a denominator that is a power of twos. The multiplication-free processing may be used for various transforms (e.g., DCT and IDCT), filters, and other types of signal and data processing.

Abstract: A method, apparatus, and system for providing distributed source coding techniques that improve data coding performance, such as video data coding, when channel errors or losses occur. Errors in the reconstruction of the data is eliminated or reduced by sending extra information. Correlation between a predicted sequence and an original sequence can be used to design codebooks and find the cosets required to represent the original image. This information may be sent over another channel, or a secondary channel.