Abstract: It has been attracting wide attention to retrieval,analysis and understanding of huge video data.A number of content based methods for indexing and retrieving have been presented.Text detection and extraction in video images is an effective way for achieving image-content-based retrieval.This paper presents a method for detecting and locating text areas in images based on sub-image VCH.The mapping features of sub-image VCH and the relation between texts and mapping features is analyzed.And the algorithm for detecting and locating text areas in images is described.Some computing experiment results are given and analysis and evaluation are made for it in the end of the paper.