数字视频中字幕检测及提取的研究和实现

Digital Video Caption Detection and Extraction Techniques and Implementation

首先进行文字事件检测 ,然后进行边缘检测、阈值计算和边缘尺寸限制 ,最后依据文字像素密度范围进一步滤去非文字区域的视频字幕 提出的叠加水平和垂直方向边缘的方法 ,加强了检测到的文字的边缘 ;对边缘进行尺寸限制过滤掉了不符合文字尺寸的边缘 ;进一步 ,提出像素密度α的概念 ,并指出文字区域的像素密度α应在某一阈值范围之内 (αmin≤α≤αmax) 通过像素密度α滤去了非文字区域 ,应用投影法最终确定视频字幕所在区域 以上方法的结合保证了提出的算法的正确率和鲁棒性 选用不同类型的视频素材对文中算法进行实验 ,并与其他方法进行比较 。

In order to extract caption region in digital video, an algorithm is provided which first detects text event and gets edges, then makes a size restrict to the edges and eventually wipes off non text regions according to the textual energy The overlaying of detected horizontal edges and vertical edges enhances the text edges; the size restrict of edges helps to wipe off the non text edges The conception of pixel density α is presented in a threshold scope( α min ≤ α≤α max ) and used as an auxiliary measure to wipe off texture like regions Eventually image projection is applied to get text regions The combination of these methods guarantees the performance of this algorithm Our experiments show that this arithmetic has satisfactory performance of correctness and computing speed