Micro expression sequence feature extracting method based on optical flow field

A feature extraction and optical flow field technology, applied in the field of computer vision, can solve the problems of high precision face alignment and poor processing

Active Publication Date: 2015-09-23
FUDAN UNIV
View PDF3 Cites 23 Cited by
  • Summary
  • Abstract
  • Description
  • Claims
  • Application Information

AI Technical Summary

Problems solved by technology

However, micro-expression analysis has high requirements for fine alignment of faces, and this method cannot handle this problem well.

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
  • Micro expression sequence feature extracting method based on optical flow field
  • Micro expression sequence feature extracting method based on optical flow field
  • Micro expression sequence feature extracting method based on optical flow field

Examples

Experimental program
Comparison scheme
Effect test

Embodiment Construction

[0088] The present invention provides a method for describing the features of micro-expressions, and uses such features for identification and classification of micro-expressions. The following examples illustrate the application of the present invention.

[0089] In practical application, it is necessary to segment the sequence from the long-term video sequence in advance. Segmentation can use a fixed-length time window, or match a specific pattern for segmentation. The present invention does not involve segmentation technology, therefore, only a simple time window technology is used as an example below.

[0090] A high-speed camera (50-200fps) is used to capture human facial video, in which micro-expression sequences are detected and classified. Conventional 25fps cameras can also capture micro-expressions, but some extremely short micro-expressions may be missed. In addition, even for captured micro-expressions, it cannot provide temporally similar information as high-sp...

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 belongs to the technical field of computer visions, in particular a micro expression sequence feature extracting method based on an optical flow field. The method comprises the following steps: firstly extracting a dense optical flow field between adjacent frames in the premise that the frame number of the micro expression is fixed; eliminating the influence of the human face translation to the micro expression recognition through fine alignment; and then segmenting the aligned optical flow fields into a series of space-time sub-blocks, extracting a main direction in each space-time sub-block to represent the motion pattern of majority points in the sub-block; quantizing and splicing main directions in all sub-blocks, and expressing in a vector form, namely obtaining the designed micro expression sequence feature. The novel feature based on the motion description provided by the invention can be used for the micro expression recognition. Through the adoption of the method disclosed by the invention, the comprehensive indexes such as accuracy, precision and recalling rate are superior to other existing methods, and the further development of the micro expression recognition technology is promoted; and meanwhile, the method is capable of depicting the dynamic pattern of the micro expression and providing deeper understanding for the analysis of the micro expression.

Description

technical field [0001] The invention belongs to the technical field of computer vision, and in particular relates to a micro-expression sequence feature extraction method based on an optical flow field. Background technique [0002] At present, there are many difficulties in micro-expression recognition, and practical methods and theoretical frameworks have not yet been formed at this stage. Its difficulty is mainly manifested in feature extraction. The currently used features are often general-purpose video feature expressions, which are not optimized for the application of micro-expressions, nor can they provide a deep understanding of micro-expressions. [0003] Microexpressions were first discovered in 1969 when psychologists observed videotaped conversations with depressed patients [1]. The patients in the video often show a normal smile, however, a few frames of abnormally distressed expressions can be found. Psychologists call them microexpressions. [0004] Unlik...

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
Patent Type & Authority Applications(China)
IPC IPC(8): G06K9/00
CPCG06V40/174G06V40/168
Inventor 徐峰张军平
Owner FUDAN 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