Patents by Inventor Alexandros Tourapis

Alexandros Tourapis has filed for patents to protect the following inventions. This listing includes patent applications that are pending as well as patents that have already been granted by the United States Patent and Trademark Office (USPTO).

  • Patent number: 11683525
    Abstract: A system comprises an encoder configured to compress attribute and/or spatial information for a point cloud and/or a decoder configured to decompress compressed attribute and/or spatial information for the point cloud. To compress the attribute and/or spatial information, the encoder is configured to convert a point cloud into an image based representation. Also, the decoder is configured to generate a decompressed point cloud based on an image based representation of a point cloud. In some embodiments, an encoder performs downscaling of an image frame prior to video encoding and a decoder performs upscaling of an image frame subsequent to video decoding.
    Type: Grant
    Filed: November 10, 2021
    Date of Patent: June 20, 2023
    Assignee: Apple Inc.
    Inventors: Khaled Mammou, Yeping Su, Jungsun Kim, Valery G. Valentin, David W. Singer, Fabrice A. Robinet, Hsi-Jung Wu, Alexandros Tourapis
  • Publication number: 20230188733
    Abstract: Video coding schemes may include one or more filters to reduce coding artifacts and improve video quality. These filters may be applied to decode video data in a predetermined sequence. The output from one or more of these filters may be selected for different images, blocks, or sets of video data and then copied and/or routed to a display or a buffer storing reference data that is used to decode other video data in a data stream. Providing the ability to select which filter output is used for display and as a reference may result in better video quality for multiple types of video data. The filters that are selected for display and for reference may be different and may vary for different images, blocks, and data sets.
    Type: Application
    Filed: February 13, 2023
    Publication date: June 15, 2023
    Inventors: Alexandros TOURAPIS, Athanasios LEONTARIS
  • Publication number: 20230188738
    Abstract: In an example method, a decoder obtains a data stream representing video content. The video content is partitioned into one or more logical units, and each of the logical units is partitioned into one or more respective logical sub-units. The decoder determines that the data stream includes first data indicating that a first logical unit has been encoded according to a flexible skip coding scheme. In response, the decoder determines a first set of decoding parameters based on the first data, and decodes each of the logical sub-units of the first logical unit according to the first set of decoding parameters.
    Type: Application
    Filed: December 6, 2022
    Publication date: June 15, 2023
    Inventors: Alican Nalci, Alexandros Tourapis, Hilmi Enes Egilmez, Hsi-Jung Wu, Jun Xin, Yeqing Wu, Yixin Du, Yunfei Zheng
  • Patent number: 11677982
    Abstract: An encoding device evaluates a plurality of processing and/or post-processing algorithms and/or methods to be applied to a video stream, and signals a selected method, algorithm, class or category of methods/algorithms either in an encoded bitstream or as side information related to the encoded bitstream. A decoding device or post-processor utilizes the signaled algorithm or selects an algorithm/method based on the signaled method or algorithm. The selection is based, for example, on availability of the algorithm/method at the decoder/post-processor and/or cost of implementation. The video stream may comprise, for example, downsampled multiplexed stereoscopic images and the selected algorithm may include any of upconversion and/or error correction techniques that contribute to a restoration of the downsampled images.
    Type: Grant
    Filed: September 13, 2022
    Date of Patent: June 13, 2023
    Assignee: Dolby Laboratories Licensing Corporation
    Inventors: Alexandros Tourapis, Athanasios Leontaris, Peshala V. Pahalawatta, Kevin J. Stec
  • Patent number: 11676309
    Abstract: A system comprises an encoder configured to compress attribute information and/or spatial for a point cloud and/or a decoder configured to decompress compressed attribute and/or spatial information for the point cloud. To compress the attribute and/or spatial information, the encoder is configured to convert a point cloud into an image based representation. Also, the decoder is configured to generate a decompressed point cloud based on an image based representation of a point cloud.
    Type: Grant
    Filed: September 3, 2021
    Date of Patent: June 13, 2023
    Assignee: Apple Inc
    Inventors: Alexandros Tourapis, Khaled Mammou, Yeping Su, Fabrice A. Robinet, David W. Singer
  • Patent number: 11663744
    Abstract: A system comprises an encoder configured to compress attribute information and/or spatial for a point cloud and/or a decoder configured to decompress compressed attribute and/or spatial information for the point cloud. To compress the attribute and/or spatial information, the encoder is configured to convert a point cloud into an image based representation. Also, the decoder is configured to generate a decompressed point cloud based on an image based representation of a point cloud. A processing/filtering element utilizes occupancy map information and/or auxiliary patch information to determine relationships between patches in image frames and adjusts encoding/decoding and/or filtering or pre/post-processing parameters based on the determined relationships.
    Type: Grant
    Filed: May 3, 2021
    Date of Patent: May 30, 2023
    Assignee: Apple Inc.
    Inventors: Alexandros Tourapis, Khaled Mammou, Yeping Su, Jungsun Kim, Valery G. Valentin, David W. Singer, Fabrice A. Robinet, Hsi-Jung Wu
  • Patent number: 11659182
    Abstract: A method of signaling additional chroma QP offset values that are specific to quantization groups is provided, in which each quantization group explicitly specifies its own set of chroma QP offset values. Alternatively, a table of possible sets of chroma QP offset values is specified in the header area of the picture, and each quantization group uses an index to select an entry from the table for determining its own set of chroma QP offset values. The quantization group specific chroma QP offset values are then used to determine the chroma QP values for blocks within the quantization group in addition to chroma QP offset values already specified for higher levels of the video coding hierarchy.
    Type: Grant
    Filed: April 16, 2021
    Date of Patent: May 23, 2023
    Assignee: Apple Inc.
    Inventors: Alexandros Tourapis, Guy Cote
  • Publication number: 20230143147
    Abstract: A cross-component based filtering system is disclosed for video coders and decoders. The filtering system may include a filter having an input for a filter offset and an input for samples reconstructed from coded video data representing a native component of source video on which the filter operates. The offset may be generated at least in part from a sample classifier that classifies samples reconstructed from coded video data representing a color component of the source video orthogonal to the native component according to sample intensity.
    Type: Application
    Filed: November 2, 2022
    Publication date: May 11, 2023
    Inventors: Yixin DU, Alexandros TOURAPIS, Yunfei ZHENG, Jun XIN, Alican NALCI, Mei T. GUO, Yeqing WU, Hsi-Jung WU
  • Publication number: 20230142771
    Abstract: A filtering system for video coders and decoders is disclosed that includes a feature detector having an input for samples reconstructed from coded video data representing a color component of source video, and having an output for data identifying a feature recognized therefrom, an offset calculator having an input for the feature identification data from the feature detector and having an output for a filter offset, and a filter having an input for the filter offset from the offset calculator and an input for the reconstructed samples, and having an output for filtered samples. The filtering system is expected to improve operations of video coder/decoder filtering systems by selecting filtering offsets from analysis of recovered video data in a common color plane as the samples that will be filtered.
    Type: Application
    Filed: November 2, 2022
    Publication date: May 11, 2023
    Inventors: Yixin DU, Alexandros TOURAPIS, Yunfei ZHENG, Jun XIN, Mukta S. Gore, Alican NALCI, Mei T. GUO, Yeqing WU, Hsi-Jung WU
  • Patent number: 11647226
    Abstract: A system comprises an encoder configured to compress attribute information and/or spatial information for a point cloud and/or a decoder configured to decompress compressed attribute and/or spatial information for the point cloud. To compress the attribute and/or spatial information, the encoder is configured to convert a point cloud into an image based representation. Also, the decoder is configured to generate a decompressed point cloud based on an image based representation of a point cloud. In some embodiments, a bit stream structure may be used to communicate compressed point cloud data. The bit stream structure may include point cloud compression network abstraction layer (PCCNAL) units that enable use of groups of frames (GOFs), frame, and sub-frame signaling of patch information. Such a bit stream structure may permit low delay streaming and random access reconstruction of point clouds amongst other applications.
    Type: Grant
    Filed: May 12, 2021
    Date of Patent: May 9, 2023
    Assignee: Apple Inc.
    Inventors: Jungsun Kim, Alexandros Tourapis, Khaled Mammou, Fabrice A. Robinet, Yeping Su, David W. Singer
  • Publication number: 20230125227
    Abstract: A system comprises an encoder configured to compress attribute information and/or spatial for a point cloud and/or a decoder configured to decompress compressed attribute and/or spatial information for the point cloud. To compress the attribute and/or spatial information, the encoder is configured to convert a point cloud into an image based representation. Also, the decoder is configured to generate a decompressed point cloud based on an image based representation of a point cloud.
    Type: Application
    Filed: December 8, 2022
    Publication date: April 27, 2023
    Applicant: Apple Inc.
    Inventors: Khaled Mammou, Fabrice A. Robinet, Alexandros Tourapis, Yeping Su
  • Publication number: 20230117479
    Abstract: Overlapped block disparity estimation and compensation is described. Compensating for images with overlapped block disparity compensation (OBDC) involves determining if OBDC is enabled in a video bit stream, and determining if OBDC is enabled for one or more macroblocks that neighbor a first macroblock within the video bit stream. The neighboring macroblocks may be transform coded. If OBDC is enabled in the video bit stream and for the one or more neighboring macroblocks, predictions may be made for a region of the first macroblock that has an edge adjacent with the neighboring macroblocks. OBDC can be causally applied. Disparity compensation parameters or modes may be shared amongst views or layers. A variety of predictions may be used with causally-applied OBDC.
    Type: Application
    Filed: December 15, 2022
    Publication date: April 20, 2023
    Inventors: Alexandros Tourapis, Athanasios Leontaris
  • Patent number: 11627343
    Abstract: In communication applications, aggregate source image data at a transmitter exceeds the data that is needed to display a rendering of a viewport at a receiver. Improved streaming techniques that include estimating a location of a viewport at a future time. According to such techniques, the viewport may represent a portion of an image from a multi-directional video to be displayed at the future time, and tile(s) of the image may be identified in which the viewport is estimated to be located. In these techniques, the image data of tile(s) in which the viewport is estimated to be located may be requested at a first service tier, and the other tile in which the viewport is not estimated to be located may be requested at a second service tier, lower than the first service tier.
    Type: Grant
    Filed: March 1, 2021
    Date of Patent: April 11, 2023
    Assignee: APPLE INC.
    Inventors: Xiaohua Yang, Alexandros Tourapis, Dazhong Zhang, Hang Yuan, Hsi-Jung Wu, Jae Hoon Kim, Jiefu Zhai, Ming Chen, Xiaosong Zhou
  • Patent number: 11627314
    Abstract: A system comprises an encoder configured to compress attribute and/or spatial information for a point cloud and/or a decoder configured to decompress compressed attribute and/or spatial information for the point cloud. To compress the attribute and/or spatial information, the encoder is configured to convert a point cloud into an image based representation. Also, the decoder is configured to generate a decompressed point cloud based on an image based representation of a point cloud. In some embodiments, an encoder applies an attribute transfer function to attributes of an image based representation with out-of-loop smoothing such that a decoder may apply any smoothing filter supported by the decoder without being restricted to using a similar smoothing filter as the encoder.
    Type: Grant
    Filed: September 24, 2020
    Date of Patent: April 11, 2023
    Assignee: Apple Inc.
    Inventors: Alexandros Tourapis, Jungsun Kim, Khaled Mammou, Dominik Mehlem
  • Patent number: 11622130
    Abstract: Sampled data is packaged in checkerboard format for encoding and decoding. The sampled data may be quincunx sampled multi-image video data (e.g., 3D video or a multi-program stream), and the data may also be divided into sub-images of each image which are then multiplexed, or interleaved, in frames of a video stream to be encoded and then decoded using a standardized video encoder. A system for viewing may utilize a standard video decoder and a formatting device that de-interleaves the decoded sub-images of each frame reformats the images for a display device. A 3D video may be encoded using a most advantageous interleaving format such that a preferred quality and compression ratio is reached. In one embodiment, the invention includes a display device that accepts data in multiple formats.
    Type: Grant
    Filed: December 16, 2021
    Date of Patent: April 4, 2023
    Assignee: Dolby Laboratories Licensing Corporation
    Inventors: Alexandros Tourapis, Walter J. Husak, Peshala V. Pahalawatta, Athanasios Leontaris
  • Publication number: 20230096567
    Abstract: Improved neural-network-based image and video coding techniques are presented, including hybrid techniques that include both tools of a host codec and neural-network-based tools. In these improved techniques, the host coding tools may include conventional video coding standards such H.266 (VVC). In an aspects, source frames may be partitioned and either host or neural-network-based tools may be selected per partition. Coding parameter decisions for a partition may be constrained based on the partitioning and coding tool selection. Rate control for host and neural network tools may be combined. Multi-stage processing of neural network output may use a checkerboard prediction pattern.
    Type: Application
    Filed: September 23, 2022
    Publication date: March 30, 2023
    Inventors: Alican NALCI, Alexandros TOURAPIS, Hsi-Jung WU, Jiefu ZHAI, Jingteng XUE, Jun XIN, Mei GUO, Xingyu ZHANG, Yeqing WU, Yunfei ZHENG, Jean Begaint
  • Publication number: 20230095473
    Abstract: A system comprises an encoder configured to compress attribute information and/or spatial for a point cloud and/or a decoder configured to decompress compressed attribute and/or spatial information for the point cloud. A point cloud attribute transfer algorithm may be used to determine distortion between an original point cloud and a reconstructed point cloud. Additionally, the point cloud attribute transfer algorithm may be used to select attribute values for a reconstructed point cloud such that distortion between an original point cloud and a reconstructed version of the original point cloud is minimized.
    Type: Application
    Filed: November 4, 2022
    Publication date: March 30, 2023
    Applicant: Apple Inc.
    Inventors: Khaled Mammou, Yeping Su, Alexandros Tourapis, Jungsun Kim, Valery G. Valentin, Fabrice A. Robinet
  • Publication number: 20230094734
    Abstract: A system comprises an encoder configured to compress attribute information and/or spatial information for volumetric visual content and/or a decoder configured to decompress compressed attribute and/or spatial information for the volumetric visual content. The encoder is configured to convert a 3D representation of the visual volumetric content into a 2D image based representation. The encoder is further configured to scale the patch in 2D space independent of any scaling in 3D space. Auxiliary information is signaled for use in identifying 2D scaled or unscaled patches in an image frame, mapping the patches into 3D space, and adjusting for any scaling factors applied at the encoder.
    Type: Application
    Filed: October 14, 2022
    Publication date: March 30, 2023
    Applicant: Apple Inc.
    Inventors: Jungsun Kim, Khaled Mammou, Alexandros Tourapis
  • Patent number: 11616960
    Abstract: System and method for improving video encoding and/or video decoding. In embodiments, a video encoding pipeline includes a main encoding pipeline that compresses source image data corresponding with an image frame by processing the source image data based at least in part on encoding parameters to generate encoded image data. Additionally the video encoding pipeline includes a machine learning block communicatively coupled to the main encoding pipeline, in which the machine learning block analyzes content of the image frame by processing the source image data based at least in part on machine learning parameters implemented in the machine learning block when the machine learning block is enabled by the encoding parameters; and the video encoding pipeline adaptively adjusts the encoding parameters based at least in part on the content expected to be present in the image frame to facilitate improving encoding efficiency.
    Type: Grant
    Filed: March 23, 2021
    Date of Patent: March 28, 2023
    Assignee: Apple Inc.
    Inventors: Jim C. Chou, Alexandros Tourapis
  • Patent number: 11606569
    Abstract: Support for additional components may be specified in a coding scheme for image data. A layer of a coding scheme that specifies color components may also specify additional components. Characteristics of the components may be specified in the same layer or a different layer of the coding scheme. An encoder or decoder may identify the specified components and determine the respective characteristics to perform encoding and decoding of image data.
    Type: Grant
    Filed: September 25, 2019
    Date of Patent: March 14, 2023
    Assignee: Apple Inc.
    Inventors: Alexandros Tourapis, Yeping Su, Khaled Mammou, Jungsun Kim, David W. Singer, Fabrice A. Robinet, Guy Cote, Jim C. Chou, Hsi-Jung Wu