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US-12621452-B2 - Image processing device and method

US12621452B2US 12621452 B2US12621452 B2US 12621452B2US-12621452-B2

Abstract

The present disclosure relates to an image processing device and method for enabling control of a value of a quantization parameter within a desired range. A quantization parameter is corrected on the basis of a parameter regarding adaptive color transform and further correcting the quantization parameter on the basis of a parameter regarding transform skip, and coefficient data of an image to be encoded is quantized using a corrected quantization parameter that is the quantization parameter that has been corrected. The present disclosure can be applied to, for example, an image processing device, an image encoding device, an image decoding device, a transmission device, a reception device, a transmission/reception device, an information processing device, an imaging device, a reproduction device, an electronic device, an image processing method, an information processing method, or the like.

Inventors

  • Takeshi Tsukuba

Assignees

  • Sony Group Corporation

Dates

Publication Date
20260505
Application Date
20241119

Claims (14)

  1. 1 . An image processing device comprising: circuitry configured to clip, as a minimum value of a quantization parameter of a case of applying the transform skip, a lower limit of a quantization parameter corrected on a basis of a parameter regarding adaptive color transform; and quantize coefficient data of an image to be encoded by using a corrected quantization parameter that is the quantization parameter clipped by the quantization parameter correction unit.
  2. 2 . The image processing device according to claim 1 , wherein, the circuitry is further configured to clip, as a sum of a maximum value of the quantization parameter and a correction amount based on a bit depth, an upper limit of the quantization parameter corrected on a basis of the parameter regarding adaptive color transform.
  3. 3 . The image processing device according to claim 2 , wherein, the circuitry is further configured to clip, as a minimum value in a case of not applying the transform skip, clip the lower limit of the quantization parameter corrected on a basis of the parameter regarding adaptive color transform.
  4. 4 . The image processing device according to claim 3 , wherein, the circuitry is configured to clip, as the sum of the maximum value of the quantization parameter and the correction amount based on the bit depth, the upper limit of the quantization parameter corrected on a basis of the parameter regarding adaptive color transform.
  5. 5 . The image processing device according to claim 1 , wherein, the circuitry is further configured to correct according to a correction amount corresponding to a component to be processed.
  6. 6 . The image processing device according to claim 5 , wherein, under a condition of not applying the transform skip, the correction amount is 0.
  7. 7 . An image processing method comprising: clipping, as a minimum value of a quantization parameter of a case of applying the transform skip, a lower limit of a quantization parameter corrected on a basis of a parameter regarding adaptive color transform; and quantizing coefficient data of an image to be encoded by using a corrected quantization parameter that is the quantization parameter clipped by the clipping.
  8. 8 . An image processing device comprising: circuitry configured to clip, as a minimum value of a quantization parameter of a case of applying a transform skip, a lower limit of a quantization parameter corrected on a basis of a parameter regarding adaptive color transform; and inversely quantize quantized coefficient data that is obtained by quantizing coefficient data of an image by using a corrected quantization parameter that is the quantization parameter clipped by the circuitry.
  9. 9 . The image processing device according to claim 8 , wherein, the circuitry is further configured to clips, as a sum of a maximum value of the quantization parameter and a correction amount based on a bit depth, an upper limit of the quantization parameter corrected on a basis of the parameter regarding adaptive color transform.
  10. 10 . The image processing device according to claim 9 , wherein, the circuitry is configured to clip, as a minimum value in a case of not applying the transform skip, the lower limit of the quantization parameter corrected on a basis of the parameter regarding adaptive color transform.
  11. 11 . The image processing device according to claim 10 , wherein, the circuitry is configured to clip, as the sum of the maximum value of the quantization parameter and the correction amount based on the bit depth, the upper limit of the quantization parameter corrected on a basis of the parameter regarding adaptive color transform.
  12. 12 . The image processing device according to claim 8 , wherein, the circuitry is configured to correct according to a correction amount corresponding to a component to be processed.
  13. 13 . The image processing device according to claim 12 , wherein, under a condition of not applying the transform skip, the correction amount is 0.
  14. 14 . An image processing method comprising: clipping, as a minimum value of a quantization parameter of a case of applying a transform skip, a lower limit of a quantization parameter corrected on a basis of a parameter regarding adaptive color transform; and inversely quantizing quantized coefficient data that is obtained by quantizing coefficient data of an image by using a corrected quantization parameter that is the quantization parameter clipped by the clipping.

Description

CROSS-REFERENCE TO RELATED APPLICATIONS This is a continuation application of U.S. patent application Ser. No. 17/781,732, filed Jun. 2, 2022, which is based on PCT filing PCT/JP2020/047338, filed Dec. 18, 2020, which claims priority to U.S. Provisional Application No. 62/950,055, filed Dec. 18, 2019, the entire contents of each are incorporated herein by reference. TECHNICAL FIELD The present disclosure relates to an image processing device and method, and particularly relates to an image processing device and method for enabling control of a value of a quantization parameter within a desired range. BACKGROUND ART In the past, there has been proposed an encoding method for deriving a prediction residual of a moving image, performing coefficient transform, quantizing, and encoding (for example, see Non-Patent Documents 1 and 2). Furthermore, as an encoding tool for improving encoding efficiency in RGB444, adaptive color transform (ACT) for executing RGB-to-YCgCo transform on a residual domain has been proposed (see, for example, Non-Patent Document 3). Furthermore, Non-Patent Document 3 has proposed processing of correcting a quantization parameter qP to be applied to a residual of each component by (dqPY, dqPCg, dqPCo)=(−5, −5, −3) in consideration of transform of a dynamic range of a signal between the residual before the transform (C0, C1, C2) and the residual after the transform (C0′, C1′, C2′). Non-Patent Document 1 discloses a method of correcting a quantization parameter based on application of transform skip and adaptive color transform. CITATION LIST Non-Patent Document Non-Patent Document 1: Benjamin Bross, Jianle Chen, Shan Liu, Ye-Kui Wang, “Versatile Video Coding (Draft 7)”, JVET-P2001-VE, Joint Video Experts Team (JVET) of ITU-T SG 16 WP 3 and ISO/IEC JTC 1/SC 29/WG 11 16th Meeting: Feneva, CH, 1-11 Oct. 2019Non-Patent Document 2: Jianle Chen, Yan Ye, Seung Hwan Kim, “Algorithm description for Versatile Video Coding and Test Model 7 (VTM 7)”, JVET-P2002-v1, Joint Video Experts Team (JVET) of ITU-T SG 16 WP 3 and ISO/IEC JTC 1/SC 29/WG 11 16th Meeting: Geneva, CH, 1-11 Oct. 2019Non-Patent Document 3: Xiaoyu Xiu, Yi-Wen Chen, Tsung-Chuan Ma, Hong-Jheng Jhu, Xianglin Wang, “Support of adaptive color transform for 444 video coding in VVC”, JVET-P0517_r1, Joint Video Experts Team (JVET) of ITU-T SG 16 WP 3 and ISO/IEC JTC 1/SC 29/WG 11 16th Meeting: Geneva, CH, 1-11 Oct. 2019 SUMMARY OF THE INVENTION Problems to be Solved by the Invention However, in the case of the method disclosed in Non-Patent Document 1, after correction of the quantization parameter based on a parameter regarding the transform skip is executed, correction of the quantization parameter based on a parameter regarding the adaptive color transform is executed. In the correction of the quantization parameter based on the parameter regarding the transform skip, a value of the quantization parameter is clipped within a desired range. Furthermore, in the correction of the quantization parameter based on the parameter regarding the adaptive color transform, a predetermined correction amount is added. Therefore, in this method, the range that can be taken by the value of the corrected quantization parameter cannot be controlled. The present disclosure has been made in view of such a situation, and enables control of a value of a quantization parameter within a desired range. Solutions to Problems An image processing device according to one aspect of the present technology is an image processing device that includes: a quantization parameter correction unit configured to correct a quantization parameter on the basis of a parameter regarding adaptive color transform and further correct the quantization parameter on the basis of a parameter regarding transform skip; and a quantization unit configured to quantize coefficient data of an image to be encoded by using a corrected quantization parameter that is the quantization parameter corrected by the quantization parameter correction unit. An image processing method according to one aspect of the present technology is an image processing method that includes: correcting a quantization parameter on the basis of a parameter regarding adaptive color transform and further correcting the quantization parameter on the basis of a parameter regarding transform skip; and quantizing coefficient data of an image to be encoded by using a corrected quantization parameter that is the quantization parameter that has been corrected. An image processing device according to another aspect of the present technology is an image processing device that includes: a quantization parameter correction unit configured to correct a quantization parameter on the basis of a parameter regarding adaptive color transform and further correct the quantization parameter on the basis of a parameter regarding transform skip; and an inverse quantization unit configured to inversely quantize quantized coefficient data that is obta