For the mainstream lip motion and voice coherence judgment method

the whole sentence (segment) is analyzed without screening the content. This leads to large dictionary size and high computational complexity

and the result is vulnerable to weak related segments such as mute. Considering the vowel with significant lip shape changes as a representative pronunciation event and combining with the statistical results of the audio-visual initial delay distribution range

a consistent decision method based on audio-visual matching of vowel pronunciation events and position delay analysis is proposed. Firstly

the dictionary learning data is selected by the proposed audio-visual vowel segmentation method

and then the vowel dictionary is used to analyze the matching of the vowel event

and the time delay distribution of each vowel position is statistically scored. A consistency judgment is made by a scoring mechanism in which the vowel pronunciation event lip matching score and the position delay analysis score are combined. Experimental results show that the proposed method is superior to compared algorithms in recognition performance and reduces the amount of computation compared with the traditional dictionary method.