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Chia-Yuan Teng, San Diego US

Chia-Yuan Teng, San Diego, CA US

Patent application numberDescriptionPublished
20080232478Methods of Performing Error Concealment For Digital Video - Error concealment is used to hide the effects of errors detected within digital video information. A complex error concealment mode decision is disclosed to determine whether spatial error concealment (SEC) or temporal error concealment (TEC) should be used. The error concealment mode decision system uses different methods depending on whether the damaged frame is an intra-frame or an inter-frame. If the video frame is an intra-frame then a similarity metric is used to determine if the intra-frame represents a scene-change or not. If the video frame is an intra-frame, a complex multi-termed equation is used to determine whether SEC or TEC should be used. A novel spatial error concealment technique is disclosed for use when the error concealment mode decision determines that spatial error concealment should be used for reconstruction. The novel spatial error concealment technique divides a corrupt macroblock into four different regions, a corner region, a row adjacent to the corner region, a column adjacent to the corner region, and a remainder main region. Those regions are then reconstructed in that order and information from earlier reconstructed regions may be used in later reconstructed regions. Finally, a macroblock refreshment technique is disclosed for preventing error propagation from harming non-corrupt inter-blocks. Specifically, an inter-macroblock may be ‘refreshed’ using spatial error concealment if there has been significant error caused damage that may cause the inter-block to propagate the errors.09-25-2008
20090028458SCALING FILTER FOR VIDEO SHARPENING - A device has a single scaling filter to filter a video signal once to perform both sharpening and scaling. A memory stores original scaling filter coefficients for the scaling filter. An integrated circuit calculates new sharpening-scaling filter coefficients derived from the original scaling filter coefficients and one of sharpening filter coefficients for a sharpening filter and a sharpening strength and applies the new sharpening-scaling filter coefficients to the single scaling filter.01-29-2009
20090097575UNIVERSAL BLOCKINESS CORRECTION - Techniques to remove inherited blockiness with a low million instructions per second (MIPs) are provided. In one configuration, a device comprises a processor operative to implement a set of instructions to universally correct blockiness. The processor commandeers the in-loop deblocking filtering engine and universally corrects blockiness, including inherited blockiness, using the in-loop deblocking filtering engine.04-16-2009
20090147853RESOURCE-ADAPTIVE VIDEO INTERPOLATION OR EXTRAPOLATION - A decoder may apply a resource-focused interpolation mode to enable or disable interpolation or extrapolation of video units, such as frames, based on power and quality considerations. In one mode, interpolation may be disabled to conserve power when reference frames are not likely to produce satisfactory quality. In another mode, the threshold may be adjustable as a function of power saving requirements. This disclosure also describes selection of reference video frames to be used for interpolation or extrapolation of a video frame. A decoder may apply a quality-focused mode to select a reference frame based on quality criteria. The quality criteria may indicate a level of quality likely to be produced by a reference frame. If no reference frames satisfy the quality criteria, interpolation or extrapolation may be disabled. Display of an interpolated or extrapolated frame may be selectively enabled based on a quality analysis of the frame.06-11-2009
20090147854SELECTIVE DISPLAY OF INTERPOLATED OR EXTRAPOLAED VIDEO UNITS - Display of an interpolated or extrapolated video unit, such as a video frame, may be selectively enabled based on a quality analysis. This disclosure also describes selection of reference video frames to be used for interpolation or extrapolation. A decoder may apply a quality-focused mode to select a reference frame based on quality criteria. The quality criteria may indicate a level of quality likely to be produced by a reference frame. If no reference frames satisfy the quality criteria, interpolation or extrapolation may be disabled. A decoder may apply a resource-focused frame interpolation mode to enable or disable frame interpolation or extrapolation for some frames based on power and quality considerations. In one mode, frame interpolation may be disabled to conserve power when reference frames are not likely to produce satisfactory quality. In another mode, the threshold may be adjustable as a function of power saving requirements of the decoder.06-11-2009
20090148058REFERENCE SELECTION FOR VIDEO INTERPOLATION OR EXTRAPOLATION - This disclosure describes selection of reference video units to be used for interpolation or extrapolation of a video unit, such as a video frame. A decoder may apply a quality-focused mode to select a reference frame based on quality criteria. The quality criteria may indicate a level of quality likely to be produced by a reference frame. If no reference frames satisfy the quality criteria, interpolation or extrapolation may be disabled. Display of an interpolated or extrapolated frame may be selectively enabled based on a quality analysis. A decoder may apply a resource-focused frame interpolation mode to enable or disable frame interpolation or extrapolation for some frames based on power and quality considerations. In one mode, frame interpolation may be disabled to conserve power when reference frames are not likely to produce satisfactory quality. In another mode, the threshold may be adjustable as a function of power saving requirements.06-11-2009
20090213938VIDEO DECODER ERROR HANDLING - A video decoder performs a sequential error handling process to detect and conceal errors within a corrupted data segment of video data units. The decoder sequentially decodes a current data unit. Upon detecting an error, the decoder sets an error flag and resynchronizes decoding at the start of the next unit. If the error flag is set, the video decoder identifies the end of the corrupted data segment based on the start of the later unit. The decoder conceals data between the start of the current unit and the end of the corrupted data segment. If the error flag is not set, the decoder may decode the remainder of the current unit and proceed to decode the next available unit without performing error handling and concealment for the current unit. The decoder also may address reference unit mismatches caused by lost video data units.08-27-2009
20090268823BOUNDARY ARTIFACT CORRECTION WITHIN VIDEO UNITS - This disclosure describes techniques for correcting artifacts that occur along a boundary of a substitute video unit generated using video unit substitution, e.g., motion-compensated video unit interpolation or extrapolation. In accordance with the techniques described in this disclosure, a frame substitution unit identifies first locations within a substitute video unit that correspond with a boundary that exists within a reference video unit and should exist within the substitute video unit, and corrects boundary artifacts in the first locations using a first boundary artifact correction technique. The frame substitution unit also identifies second locations within the substitute video unit that correspond with a boundary that exists within the substitute video unit and does not exist within the reference video unit and corrects boundary artifacts in the second locations using a second boundary artifact correction technique.10-29-2009
20100054621DUAL LOOKUP TABLE DESIGN FOR EDGE-DIRECTED IMAGE SCALING - In general, the disclosure describes various techniques for providing edge-directed scaling filters that may be used to scale image data. An example device includes a storage medium configured to store a first lookup table and a second lookup table, and one or more processors configured to obtain one or more gradient values that each indicates a gradient between values of at least two pixels in a source image. The one or more processors are also configured to generate one or more inverse gradient values from a first lookup table based on the gradient values, and to generate one or more edge-directed scaling filter coefficients from a second lookup table based on the inverse gradient values. The one or more processors may be further configured to generate an edge-directed filter based on the coefficients, and to apply the filter to the at least two pixels to generate an interpolated pixel.03-04-2010
20100080459CONTENT ADAPTIVE HISTOGRAM ENHANCEMENT - This disclosure describes techniques for performing content adaptive histogram enhancement. In accordance with the content adaptive histogram enhancement techniques of this disclosure, a frame of digital image data, e.g., digital video data or digital still image data, is classified into one of a plurality of content classes based on histogram of pixel intensity values of the frame. The content classes may represent various levels of brightness, contrast, or the like. To classify the frame into the corresponding content class, a shape of the histogram may be analyzed using various histogram statistics. Based on the content class of the frame, the pixel intensity values of the frame are mapped to new pixel intensity values.04-01-2010
20100254453INVERSE TELECINE TECHNIQUES - This disclosure describes inverse telecine techniques that are performed to adjust or convert the frame rate of a video sequence. The described techniques provide a very useful way to identify a telecine technique that was used to increase the frame rate of a video sequence. Upon identifying the telecine technique that was used, the corresponding inverse telecine technique can be performed with respect to the sequence of video frames in order to decrease the frame rate back to its original form (prior to telecine). This disclosure also provides many useful details that can improve inverse telecine, e.g., by simplifying the inverse telecine process and by reducing memory accesses during the process.10-07-2010
20100284460VIDEO ENCODING WITH TEMPORALLY CONSTRAINED SPATIAL DEPENDENCY FOR LOCALIZED DECODING - This disclosure describes techniques for region-of-interest (ROI) encoding. In accordance with the techniques described herein, an encoding device may determine a temporal spatial dependency value for a candidate reference video block for inter-coding a current block in a video frame. The encoding device may compare the temporal spatial dependency value to a threshold value and select a coding mode for the current block based on the comparison. A decoding device may receive data defining a ROI as well as the temporal spatial dependency value and decode a video block in the ROI based at least in part on the temporal spatial dependency value. In this manner, the techniques of this disclosure may allow a video content viewer the ability to choose a ROI to watch.11-11-2010
20100284471VIDEO DECODING USING TEMPORALLY CONSTRAINED SPATIAL DEPENDENCY - This disclosure describes techniques for region-of-interest (ROI) encoding. In accordance with the techniques described herein, an encoding device may determine a temporal spatial dependency value for a candidate reference video block for inter-coding a current block in a video frame. The encoding device may compare the temporal spatial dependency value to a threshold value and select a coding mode for the current block based on the comparison. A decoding device may receive data defining a ROI as well as the temporal spatial dependency value and decode a video block in the ROI based at least in part on the temporal spatial dependency value. In this manner, the techniques of this disclosure may allow a video content viewer the ability to choose a ROI to watch.11-11-2010
20100290530MOTION VECTOR PROCESSING - This disclosure describes techniques for processing motion vectors such that the resulting motion vectors better correlate with the true motion of a video frame. In one example, the techniques may include comparing a block motion vector corresponding to a video block to a sub-block motion vector corresponding to a sub-block contained within the video block. The techniques may further include selecting one of the block motion vector and the sub-block motion vector as a spatially-estimated motion vector for the sub-block based on the comparison. Motion vectors that better correlate with true motion may be useful in applications such as motion compensated frame interpolation (MCI), moving object tracking, error concealment, or other video post-processing that requires the true motion information.11-18-2010
20110110427Selective deblock filtering techniques for video coding - This disclosure describes selective deblock filtering techniques that are particularly useful with coding standards that do not specify in-loop deblock filtering for standard compliance. In accordance with this disclosure, deblock filtering may be selectively performed with respect to block boundaries of a given video block being coded, a motion compensation process can be performed using a filtered version of the prediction video frame used to code the given video block, or both. This disclosure also provides selection rules that can be applied to determine what type of deblocking techniques to apply in various scenarios. The selection rules may improve the video coding and may also ensure that mismatch between video blocks at an encoder and a decoder is not introduced by the deblock filtering.05-12-2011

Patent applications by Chia-Yuan Teng, San Diego, CA US