数显仪表的自动识别技术对提高其使用效率，拓展使用环境等方面具有重要意义。本文针对液晶数显仪表在图像采集过程中的笔画缺失 (缺字)，提出了一种数字自动识别算法。引入二维熵阈值对待识别的图像进行二值化分割，减小照度过低或照明不均匀的影响，同时采用多次分割、编码匹配的方式对缺字数字进行识别。经过多种仪表的识别实验，结果表明该方法满足仪表数字识别的速度和准确率要求，且对图像倾斜、缩放等均有较好的适应性。

Automatic identification technology of digital display instrument has significant meaning in improving its using efficiency and environment adaptability. As to strokes missing (or character missing) in the image acquisition process, a digital automatic recognition algorithm is put forward. Two-dimensional entropy threshold is introduced in image binarization segmentation to reduce the influence of low or uneven illumination. At the same time, multiple segmentation and coding matching method is used to identify the missing characters and numbers. After a variety of instrument recognition experiments, the results show that this method can meet the time and accuracy requirements in digital display instruments, and has better adaptability to situation like image tilt, zoom and so on.