There are certain cases where the image in the document might extend to the borders of the image. In such scenarios initializing the end point of the tracers becomes difficult, as it would be inside the image region. This might make the trace
paths complex and contoured. This scenario can be overcome by padding couple of rows and couple of columns of zeros to
the four extremes of the document. This embeds the document scan in a frame suitable for trace analysis. We would pursue
this as part of future work.