Abstract: An alpha-map encoding apparatus includes a first down-sampling circuit (21) for down-sampling an alpha-map signal which represents the shape of an object and the position in the frame of the object at a down-sampling ratio based on size conversion ratio information, an up-sampling circuit (23) for up-sampling the alpha-map signal at an up-sampling ratio based on size conversion ratio information given to restore the down-sampled alpha-map signal to an original size, and outputting a local decoded alpha-map signal, a motion estimation/compensation circuit (25) for generating a motion estimation/compensation signal on the basis of the previous decoded video signal and a motion vector signal, a second down-sampling circuit (26) for down-sampling the motion estimation/compensation signal at the down-sampling ratio, a binary image encoder for encoding the alpha-map signal down-sampled by the first down-sampling circuit to a binary image in accordance with the motion estimation/compensation signal down-sampled by t

Abstract: A video compression method is provided and implemented in a pixel processing controller of a digital solid-state imaging device for maximizing throughput of digitized video data on a link between the digital solid-state imaging device and a host computer. The method performs separate luminance (Y) domain compression of the video data on a line-by-line basis, without storing video data lines or video data frames, and separate chrominance (Cr/Cb) domain averaging of the video data on a region-by-region basis without storing video data in video frames. The Y and Cr/Cb domain compression steps are implemented in the digital solid-state imaging device hardware for real time link transmission of the compressed video data to the host computer.

Abstract: A video processor receives coded digital image data which is decoded into MPEG compatible pixel blocks. The pixel blocks are horizontally and vertically decimated to produce a reduced size image suitable for picture-in-picture, picture-on-picture, or picture-in-graphics display. Decoded input data to the decimation network is alias filtered and decimated at a factor of 8 to 3. Decimated output pixel data is derived solely from a respectively associated decoded input pixel block.

Abstract: An HDTV down conversion system including an apparatus for forming a low resolution video signal from an encoded video signal representing a video image. The encoded video signal is a frequency-domain transformed high resolution video signal with motion vectors. The apparatus includes a receiver for receiving the encoded video signal as a plurality of blocks of high resolution frequency-domain video coefficient values. A plurality of blocks comprises a macroblock. A down-conversion filter weights selected ones of the high resolution frequency-domain video coefficient values within each block to generate corresponding blocks of filtered frequency-domain video coefficients. An inverse-transform processor transforms each block of filtered frequency-domain video coefficients into a block of first-filtered pixel values. A pre-decimation filter performs inter-macroblock inter-block filtering of the plurality of blocks of first-filtered pixel values and provides corresponding blocks of second-filtered pixel values.

Abstract: Methods and apparatus for implementing a reduced cost HDTV/SDTV video decoder are disclosed. The described joint video decoder is capable of decoding HDTV pictures at approximately the resolution of standard definition television pictures and can be used to decode HDTV and/or SDTV pictures. The described video decoder may be used as part of a picture-in-picture decoder circuit for providing picture-in-picture capability without providing multiple full resolution video decoders. The reduction in decoder circuit complexity is achieved through the use of a plurality of data reduction techniques including the use of a preparser, downsampling, and truncating pixel values.

Abstract: An apparatus for decoding coded video data is provided which is capable of decreasing the storage size of its frame memory while attenuating the drift noise and minimizing lowering of the resolution during the reconstruction of the coded video data. The apparatus comprises a data size reducer for reducing the size of a decoded video data reconstructed by subsampling, pixel differential coding, or other methods, a frame memory for saving a reduced video data released from the data size reducer, and a data size recover for recovering the original size of the decoded video data from the reduced data saved in the frame memory. Accordingly, the storage size of the frame memory is decreased by a combination of compression of pixel data and IDCT processing in a reduced block size and will successfully attenuate unwanted drift noise and minimize declination of the resolution.

Abstract: A method comprising constructing virtual (Discrete Wavelet Transform) DWT sub-bands; from an image without performing the DWT and then applying an inverse DWT upon the virtual sub-bands, the result of the inverse DWT representing an up-sampled version of the image. Alternatively, an apparatus comprising an interface configured to communicate image data, and an up-sampling unit, the up-sampling unit coupled to the interface to receive the image data, the up-sampling unit configured to construct virtual sub-band input data from the image data, the up-sampling unit configured to perform an inverse DWT upon the input data generating an up-sampled image therefrom.

Abstract: The invention relates to a low/very low bitrate video coding method fully compatible with the H.263 standard includes a first forward coding step, a second backwards prediction step, and a third decision step including a selection sub-step between intra and inter coding modes. This decision step controls in the intra coding mode a down-conversion filtering sub-step, carried out at the beginning of the coding step and allowing to code and transmit original intra pictures with a lower resolution, and a corresponding up-conversion filtering sub-step, carried out in the prediction step. In the receiving terminal, the decoder recognizes the reduced format of the pictures and up-scales them.

Abstract: A video decoder for high definition television includes a variable length decoder decoding codes corresponding to discrete cosine transform (DCT) coefficients of an applied video bit stream, and produces a run-level pair for each code. An index decoder stores run-level pairs produced from the variable length decoder, and produces the position information indicating the number of a level value of a corresponding run-level pair among 64 DCT coefficients. An inverse quantizer obtains an added value corresponding to the position information of the index decoder from a quantization matrix, and performs an inverse quantization by multiplying a quantizer level for determining a quantization step and DCT coefficient to the added value. An inverse scanner includes a plurality of memories, and inversely scanning the DCT coefficient inversely quantized and applied serially from the inverse quantizer and produces the DCT coefficient in parallel at the same time.

Abstract: It is possible to produce a decoded image with a high image quality from data of the lowermost hierarchy obtained during hierarchical coding operation. An image of a first hierarchy equal to an original image is successively thinned in thinning units so that an image of a second hierarchy and an image of a third hierarchy are formed. Then, in an optimum correction data calculating unit, the image of the second hierarchy is corrected, a prediction value of the image of the first hierarchy is predicted from the resultant correction data, and correction data of the image of the second hierarchy is generated to reduce a prediction error of the prediction value lower than a preselected threshold. In another optimum correction data calculating unit, correction data of the image of the third hierarchy is similarly obtained.

Abstract: A picture signal encoding apparatus and a picture signal decoding apparatus are disclosed. The picture signal encoding apparatus includes: first compression coding device for converting and compression-coding basic picture signals having a sampling frequency ratio of a luminance signal and two color-difference signals of 4:2:2 to have a sampling frequency ratio of the luminance signal and the two color-difference signals of 4:1:1 or 4:2:0 so as to generate first compressed data; encoding residual extracting device for extracting an encoding residual between the basic picture signals and the compressed data; and second compression coding device for compression-coding the extracted encoding residual so as to generate second compressed data.

Abstract: An apparatus and method provides is configured such that a decoded image can be provided that is almost identical to the original image being encoded. In particular, corrected data of fewer pixels than the number of pixels for an original image is calculated by carrying out prescribed calculations using a pixel value for pixels of each block of the image and mapping coefficients that correspond to the class of the block. A predicted value for the original image is then estimated at a local decoder based on the corrected data. Then, at an error calculator, a prediction error for the original image for the predicted value is detected. At a mapping setting unit, a mapping coefficient corresponding to the class of the block is changed based on this prediction error. By repeating this process, mapping coefficients occurring when the prediction error is less than a prescribed threshold value are obtained.

Abstract: A filter for downsampling input video having a first chrominance sampling to a second chrominance sampling. The input video has a Bitstream of data representing a sequence of picture frames, where each picture frame has a plurality of video lines. The filter has a means for choosing a downsampling mode from a list of available downsampling modes for the downsampling of the first chrominance sampling. The filter also has a means for dividing each picture frame into video line sets according to predetermined criteria for the particular downsampling mode chosen, where each video line set has at least two video lines. A means for assigning default downsampling coefficients for each of the video lines in the video line sets based upon the downsampling mode chosen is also provided in the filter. Lastly, the filter has a means for downsampling each video line set to a single video line having the second chrominance sampling.