Video encoding method and device and decoding method and device

• US 9,350,997 B2
• Filed: 09/28/2011
• Issued: 05/24/2016
• Est. Priority Date: 09/28/2010
• Status: Active Grant

• Current Assignee: Samsung Electronics Co. Ltd.
• Original Assignee: Samsung Electronics Co. Ltd.
• Inventors: Hong, Yoon-Mi, Han, Woo-Jin, Cheon, Min-Su, Chen, Jianle
• Primary Examiner(s): Anyikire, Chikaodili E
• Assistant Examiner(s): KALAPODAS, DRAMOS
• Application Number:
  US13/876,778
• Publication Number:
  US 20130188730A1
• Time in Patent Office: 1,700 Days
• US Class Current: 1/1
• CPC Class Codes: G06F 17/147 Discrete orthonormal transforms, e.g. discrete cosine transform, discrete sine transform, and variations therefrom, e.g. modified discrete cosine transform, integer transforms approximating the discrete cosine transform G06F17/145 takes precedence
• CPC Class Codes: H04N 19/126 Details of normalisation or weighting functions, e.g. normalisation matrices or variable uniform quantisers
• CPC Class Codes: H04N 19/176 the region being a block, e.g. a macroblock
• CPC Class Codes: H04N 19/60 using transform coding
• CPC Class Codes: H04N 19/625 using discrete cosine transform [DCT]

Abstract

A video encoding method, a video encoding apparatus, a video decoding method, and a video decoding apparatus, the video encoding method including producing a fast transform matrix based on a transform matrix which is used for frequency transformation on a predetermined-size block; producing a transformed block by transforming the predetermined-size block by using the fast transform matrix; and performing scaling with respect to the transformed block to correct a difference between the transform matrix used for the frequency transformation and the fast transform matrix.

Claims

1. A video decoding method comprising:

receiving a quantized transform block which has a predetermined size;

determining a scaling constant for scaling of transform coefficients included in the quantized transform block based on a quantization parameter;

scaling the transform coefficients by using the scaling constant; and

inverse-transforming the transform block that includes the scaled transform coefficients,

wherein, where i denotes a remainder after the quantization parameter is divided by 6, the scaling constant for i=0 is 40, the scaling constant for i=1 is 45, the scaling constant for i=2 is 51, the scaling constant for i=3 is 57, the scaling constant for i=4 is 64, and the scaling constant for i=5 is 72.