No-reference tone mapping image quality evaluation method

A technology of image quality evaluation and tone mapping, which is applied in the field of image processing, can solve the problems of limited performance of tone mapping image quality evaluation algorithms, and achieve the effect of high-efficiency prediction

Active Publication Date: 2019-06-11
TIANJIN UNIV
View PDF5 Cites 2 Cited by
  • Summary
  • Abstract
  • Description
  • Claims
  • Application Information

AI Technical Summary

Problems solved by technology

The performance of existing tone mapping image quality evaluation

Method used

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
View more

Image

Smart Image Click on the blue labels to locate them in the text.
Viewing Examples
Smart Image
  • No-reference tone mapping image quality evaluation method
  • No-reference tone mapping image quality evaluation method
  • No-reference tone mapping image quality evaluation method

Examples

Experimental program
Comparison scheme
Effect test

Embodiment Construction

[0013] The present invention proposes a no-reference tone mapping image quality evaluation method, the algorithm block diagram is as follows figure 1 shown.

[0014] 1. Global feature extraction

[0015] (1) Color moment

[0016] Given an image I, in the RGB color space, first decompose to obtain each color channel, and then calculate the mean, standard deviation, and skewness of the image in each color channel, and the calculation formula is as follows:

[0017]

[0018]

[0019]

[0020] Among them, p ij Represents the jth pixel of the i-th color channel, N represents the total number of pixels in the color channel, the formulas are used to calculate the mean, standard deviation and skewness, and the color moment feature is recorded as f 1 .

[0021] (2) Light and dark distribution

[0022] Convert the image I to a grayscale image and divide it into dark and light regions based on pixel values.

[0023] 1) Dark area: the image area where pixel values ​​are dis...

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
Login to view more

PUM

No PUM Login to view more

Abstract

The invention relates to a no-reference tone mapping image quality evaluation method, and the method comprises the following steps: (1), carrying out the global feature extraction: calculating a colormoment feature, and recording the color moment feature as f1; converting the to-be-evaluated image I into a grayscale image, respectively counting the proportions of all pixels falling into a dark area and a bright area of one image, and finally representing the light and shade distribution characteristics f2 of the image by using the dark area ratio and the bright area ratio; Wherein the globalentropy feature is recorded as f3; (2) performing local feature extraction: dividing the image I into 16 * 16 local blocks in a space domain, calculating the sum-difference ratio of the maximum pixelvalue Imax to the minimum pixel value Imin to the maximum pixel value B in the blocks, and recording the sum-difference ratio as a contrast ratio f4; calculating the local entropy of the image block and recording the local entropy as f5; dividing the image I into 16 * 16 blocks in a wavelet domain, uniformly expressing wavelet decomposition coefficients in four directions of approximation, horizontal, vertical and diagonal by C, carrying out energy operation on the coefficients C, and recording the wavelet energy as f6; (3) quality assessment.

Description

technical field [0001] The invention belongs to the field of image processing, and in particular relates to a no-reference quality evaluation method for tone mapping images. Background technique [0002] In recent years, high dynamic range (High Dynamic Range, HDR) display devices have gradually increased, but currently low dynamic range (Low Dynamic Range, LDR) display devices still occupy a considerable number. In order to meet the needs of LDR equipment, it is necessary to compress the high dynamic range of the real world to the low dynamic range, scholars have proposed various tone mapping operators to realize the conversion from HDR to LDR. However, the conversion process is also accompanied by various distortion phenomena, such as color imbalance and abnormal exposure, which cause uncomfortable visual experience for the viewer. For this reason, evaluating the quality of tone-mapped images has become an urgent task. The performance of existing tone mapping image quali...

Claims

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
Login to view more

Application Information

Patent Timeline
no application Login to view more
IPC IPC(8): G06K9/46G06K9/62
Inventor 侯春萍李浩岳广辉
Owner TIANJIN UNIV
Who we serve
  • R&D Engineer
  • R&D Manager
  • IP Professional
Why Eureka
  • Industry Leading Data Capabilities
  • Powerful AI technology
  • Patent DNA Extraction
Social media
Try Eureka
PatSnap group products

Browse by: Latest US Patents, China's latest patents, Technical Efficacy Thesaurus, Application Domain, Technology Topic.

© 2024 PatSnap. All rights reserved.Legal|Privacy policy|Modern Slavery Act Transparency Statement|Sitemap