Stmicroelectronics Asia Pacific Pte Limited

Stmicroelectronics (shenzhen) R&d Co. Ltd.

Patricia Wei Yin Chiang

Lucas Y W Hui

Lucas Hui

Yong Huang

Xiaoyun Deng

Kwong Huang Goh

Haiyun Wang

Yau Wai Hui

Anna Raffalli

Hui Yau Wai

Lucas YW Hui

Digital noise removal methods and systems for picture quality improvement on next generation high quality set-top-box and digital TV SOCs is disclosed with particular to a de-blocking method and system that is effective on on-grid and off-grid blocky artifacts generated by lossy video compression standards. Blocky artifacts are filtered by extracting motions vectors for a current pixel block, calculating off-grid positions based on the extracted motion vectors, and applying de-blocking filtering along the calculated off-grid positions. The methods and systems can further skip filtering on-grid blocky artifacts to be filtered by an on-grid de-blocking filter known in the art.

Motion compensated de-blocking

A method of transferring sets of video line data and macroblock data, includes the steps of determining a macroblock period and a video line period longer than the macroblock period, dividing each set of video line data to be transferred within the video line period into two or more portions according to the difference between the determined macroblock period and video line period, aligning a burst transfer of each of the portions of the divided set of video line data and each set of macroblock data to the macroblock period, and initiating the burst transfer of the sets of video line data and macroblock data at macroblock period intervals.

Memory transfer controller and method of transfer control of video line data and macroblock data

Systems and methods are disclosed for determining the perceptibility of noise in a block of images and/or video. The systems and methods may compute a mask value for the block using a block masking generator. The mask value may indicate the perceptibility of noise in the block. The mask value may be computed using a normalized activity value and/or a texture value for the block. The normalized activity value may indicate the relative activity in the block as compared to the activity in the image and/or video. The texture value may indicate the strength and/or number of edges in the block.

Perceptual block masking estimation system

A system is disclosed for reducing artifacts in images and video, such as ringing or halo artifacts. The system may include an edge detector and a gain controller. The edge detector may create an edge image used by the gain controller to create a gain image, and the gain image may be used to reduce artifacts in an image. The gain controller may, for a current pixel in the edge image, compute the maximum value of the edge image over a window containing the current pixel. The gain controller may also perform averaging to determine a maximum edge value and a current edge value, and may also use a ratio of the current edge value and the maximum edge value to determine a gain to be applied to a pixel of an image.

Method and apparatus for ringing and halo control

An automatic frequency selection circuit includes a base filter for receiving a video input, a peaking filter for receiving the video input, a first energy computation unit coupled to an output of the base filter, a second energy computation unit coupled to an output of the peaking filter, an automatic frequency control unit to compare relative measured energies of the first and second energy computation units and to output a temporarily stable selected frequency for a targeted attenuation, and a frame delay feedback unit for receiving the temporarily stable selected frequency coupled to the peaking filter.

Automatic frequency selection for peaking

In a process for enhancing contrast of an image having pixels in different brightness intensities, a histogram in discrete bins is generated. Each bin represents a pixel population of at least one pixel brightness intensity. A peak and a peak region of the histogram is then identified, wherein the peak region is a range of discrete bins around the peak. An average pixel population within the peak region is computed, and the pixel populations of the discrete bins within the peak region that exceeds the average pixel population are distributed. A transfer curve for mapping onto the image is then generated. The process can be used in an image processor for enhancing contrast of an image having pixel. Still further, a display having a receiver and a screen can include the foregoing image processor.

Automatic contrast enhancement

An edge enhancement system, including a selective edge controller for determining one or more properties of an edge of image data, and for generating one or more weighting factors on the basis of properties of the edge; and a scaling module for scaling an edge enhancement signal by the weighting factors to control the degree of edge enhancement. The image data may represent a still or moving (i.e., video) image. A max-min search circuit determines maximum and minimum turning points closest to the center of the data processing window and that are located on opposing sides of the window, to determine values and locations of maximum and minimum pixels of the edge. An edge-directed pre-filtering circuit reduces the amplification of edge fuzziness by smoothing close the edges vertical prior to enhancement. An aliasing protection circuit reduces the visibility of saw-tooth defects on predominantly horizontal diagonal edges.

Edge enhancement process and system

A method of color saturation compensation in a video signal is disclosed. The method includes the steps of: processing a luminance signal component of the video signal; determining whether the processing of the luminance signal results in a change in chrominance saturation; if the step of determining reveals that the chrominance saturation has changed, applying a chrominance compensation signal to the chrominance signals to counteract the effects of chrominance saturation, wherein the step of applying a compensation signal include the steps of: generating a compensation signal which is dependent on hue and luminance ratio (output luminance signal/input luminance signal). Apparatus for performing the method is also disclosed.

Method and apparatus for compensating for chrominance saturation

A processor for enhancing an input luminance signal including: a circuit for calculating a chroma edge value associated with the input luminance signal; a circuit for measuring a luminance gradient associated with the input luminance signal; a peaking filter for processing the input luminance signal; a gain adjustment circuit having a gain function that is adjustable relative to the calculated chroma edge value, the gain adjustment circuit being operable to adjust the magnitude of the output of the peaking filter wherein: in a first range of luminance gradients, the output is an attenuated version of the input; in a second range of luminance gradients the output is directly proportional to the input; in a third range of luminance gradients, the output is inversely proportional to the input; wherein the enhanced luminance signal is the sum of the input and output of the peaking filter.

Adaptive coring for video peaking

A method of transferring sets of video line data and macrob lock data, includes the steps of determining a macroblock period and a video line period longer than the macroblock period, dividing each set of video line data to be transferred within the video line period into two or more portions according to the difference between the determined macroblock period and video line period, aligning a burst transfer of each of the portions of the divided set of video line data and each set of macroblock data to the macroblock period, and initiating the burst transfer of the sets of video line data and macroblock data at macroblock period intervals.

Growing community of inventors

Singapore, Singapore

Patricia Wei Yin Chiang