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JP-7855773-B2 - Expandable drawing area size video coding

JP7855773B2JP 7855773 B2JP7855773 B2JP 7855773B2JP-7855773-B2

Inventors

  • ルゥ，タオラン
  • プゥ，ファーンジュイン
  • イン，プオン
  • マッカーシー，ショーン トーマス
  • チェン，タオ

Assignees

  • ドルビー ラボラトリーズ ライセンシング コーポレイション

Dates

Publication Date
20260508
Application Date
20250827
Priority Date
20190806

Claims (10)

  1. A method for decoding a coding bitstream whose drawing surface size is expandable, wherein the method is performed by a processor, Regarding pictures, The steps include receiving the current picture width and current picture height, which have unsigned integer values, A step of receiving a first offset parameter that determines a rectangular area on the current picture, wherein the first offset parameter has a signed integer value, A step of calculating the current range width and current range height of the rectangular area on the current picture based on the current picture width, the current picture height, and the first offset parameter, The steps involve accessing the reference range width, reference range height, reference range left offset, and reference range top offset, The step of calculating the horizontal magnification based on the current range width and the reference range width, wherein the step of calculating the horizontal magnification (hori_scale_fp) is as follows: A step which includes calculating fRefWidth representing the reference range width and fCurWidth representing the current range width, The step of calculating the vertical scale based on the current range height and the reference range height, wherein the step of calculating the vertical scale (vert_scale_fp) is as follows: A step which includes calculating fRefHeight representing the reference range height and fCurHeight representing the current range height, A step of calculating the left offset adjustment and the upper offset adjustment of the current range based on the first offset parameter, A step of performing motion compensation based on the horizontal magnification, the vertical magnification, the left offset adjustment, the upper offset adjustment, the left offset of the reference range, and the upper offset of the reference range, wherein the step of performing motion compensation is as follows: The steps include calculating the following: hori_scale_fp represents the horizontal scaling factor, vert_scale_fp represents the vertical scaling factor, fCurLeftOffset represents the left offset adjustment, fCurTopOffset represents the top offset adjustment, fRefLeftOffset represents the left offset of the reference range, fRefTopOffset represents the top offset of the reference range, and (refxSb L , refySb L ) and (refx L , refy L ) are the luma positions pointed to by the motion vector (refMvLX[0], refMvLX[1]) in 1/16 sample units, A method that includes this.
  2. The method according to claim 1, wherein the first offset parameter includes a left offset, an upper offset, a right offset, and a lower offset.
  3. The method according to claim 2, wherein one or more of the left offset, the upper offset, the right offset, or the lower offset have a value between -2¹⁴ and 2¹⁴ .
  4. The step of calculating the current range width includes the step of subtracting the first sum of the left offset and the right offset from the current picture width, The method according to claim 2, wherein the step of calculating the current range height includes the step of subtracting the second sum of the upper offset and the lower offset from the current picture height.
  5. The step of accessing the aforementioned reference range width and the aforementioned reference range height is performed for the reference picture, Steps to access the reference picture width and reference picture height, A step of receiving a second offset parameter that determines a rectangular area within the reference picture, wherein the second offset parameter has a signed integer value, A step of calculating the reference range width and reference range height for the rectangular range within the reference picture based on the reference picture width, the reference picture height, and the second offset parameter, The method according to claim 1, further comprising:
  6. The method according to claim 5, further comprising the step of calculating the left offset and the upper offset of the reference range based on the second offset parameter.
  7. The method according to claim 1, wherein the reference range includes a reference picture.
  8. The method according to claim 6, wherein the reference range width, reference range height, reference range left offset, and reference range upper offset are calculated based on one or more of the following parameters: the fitting window parameter of the reference picture, the reference picture width, the reference picture height, or the region of interest offset parameter.
  9. A non-temporary computer-readable storage medium storing computer-executable instructions for performing the method described in any one of claims 1 to 8 using one or more processors.
  10. A device for decoding a coding bitstream with expandable drawing surface size, the device including a processor, and configured to perform the method according to any one of claims 1 to 8.

Description

[Related applications] This application claims priority rights to U.S. Provisional Application No. 62/883,195, filed 6 August 2019, No. 62/902,818, filed 19 September 2019, and No. 62/945,931, filed 10 December 2019. [Technical Field] This specification relates in general to images. More specifically, embodiments of the present invention relate to video coding with expandable drawing surface size. When used in this specification, the term “dynamic range (DR)” may relate to the human visual system’s ability to perceive a range of intensity (e.g., luminance, lumens) within an image, from, for example, the darkest gray (black) to the brightest white (highlight). In this scene, DR relates to “scene-reference” intensity. DR may also relate to the ability of a display device to render a range of intensity within a specific width appropriately or approximately. In this scene, DR relates to “display-reference” intensity. Unless explicitly stated in any part of the description of this specification that a particular scene has a particular degree of importance, it should be presumed that the terms may be used synonymously in any of the scenes. As used in this specification, the term “high dynamic range (HDR)” refers to a DR width that is 14 to 15 times or greater than the size of the human visual system (HVS). In practice, a DR in which a wide range of intensity can be simultaneously perceived by humans may be abbreviated in some way in relation to HDR. In practice, an image contains one or more color components (e.g., lumens Y and chromins Cb and Cr), and each color component is represented with n bits per pixel (e.g., n=8). Using nonlinear luminance coding, an image where n ≤ 8 (e.g., a 24-bit color JPEG image) can be considered a standard dynamic range (SDR) image. Conversely, an image where n > 8 can be considered an extended dynamic range image. HDR images may be stored and distributed using high-resolution (e.g., 16-bit) floating-point formats, such as the OpenEXR file format developed by Industrial Light and Magic. Currently, the distribution of high dynamic range video content, such as HDR10 in Dolby Laboratories' Dolby Vision or Blu-ray®, is limited to 4K resolution (e.g., 4096 x 2160 or 3840 x 2160, etc.) and 60 frames per second (fps) due to the capabilities of many playback devices. Future versions are expected to allow for the distribution and playback of content up to 8K resolution (e.g., 7680 x 4320) and 120 fps. To simplify the HDR playback content ecosystem, such as Dolby Vision, future content types should ideally be compatible with existing playback devices. Ideally, content creators should be able to adopt and distribute future HDR technologies without having to derive and distribute special versions of content compatible with existing HDR devices (such as HDR10 or Dolby Vision). As the inventors acknowledge, improved technologies for the scalable distribution of video content, particularly HDR content, are desired. The approaches described in this chapter are pursued, but not necessarily previously conceived or pursued. Therefore, unless otherwise indicated, none of the approaches described in this chapter should be considered prior art simply by their inclusion in this chapter. Similarly, any problems identified with respect to one or more approaches should not be assumed, unless otherwise indicated, to have been recognized in any prior art based on this chapter. Embodiments of the present invention are described by example, not limiting them, and similar reference numerals in the accompanying figures represent similar elements. This illustrates an example of a video distribution pipeline. An example of a picture sub-region for defining the display area of input content according to the resolution of the target display is shown. Figure 2A shows an example of a limitation that spans boundaries in tile representation according to the embodiment, for the picture area. An example of layer-adaptive slice addressing according to an embodiment is shown. This shows an example of the possibility of spatial expansion using conventional technology. An example of the possibility of extending the drawing surface according to the embodiment is shown. Examples of base layer and extended layer pictures, and corresponding adapted windows according to the embodiment are shown. This document illustrates an exemplary processing flow that supports the possibility of expanding the drawing area size according to an embodiment of the present invention.This document illustrates an exemplary processing flow that supports the possibility of expanding the drawing area size according to an embodiment of the present invention. Exemplary embodiments relating to the expandability of the drawing surface size for video coding are described in this specification. In the following detailed description, numerous specific details are described for illustrative purposes to provide a complete understanding of the various embodiments o