Segmentation of handwritten scripts with overlapping text is one of the challenging tasks in the pre-processing for document recognition and optical character recognition (OCR) systems. It is a significant step because errors in the recognition stage will occur if text lines are not separated accurately. This paper aims to address the problem of text line segmentation of ancient Thai manuscripts written on palm leaves, in particular dealing with the issue of overlapping characters. The proposed technique is based on an integration of a partial projection method and smooth horizontal histogram with recurrence in each column. The performance evaluation of the proposed technique was compared with a modified partial projection profile. The experimental results from this study show that the accuracy of the proposed technique has a better performance. This technique will help to resolve the problem of text line segmentation for ancient Thai manuscripts on palm leaves
