1. A method of operation of an image processing system comprising: generating a binarized image of a source image; detecting character targets within the binarized image, the character targets covering contiguous portions of the binarized image; forming connected neighbors by grouping the character targets having bounding boxes with a horizontal overlap greater than a horizontal overlap threshold; forming a text unit by grouping the character targets of the connected neighbors, the character targets having a character vertical overlap greater than a character vertical overlap threshold, each of the character targets having a character feature within a feature threshold, and the text unit a portion of the source image; calculating a text unit baseline angle for rotating the text unit to the horizontal; and detecting an output text of the text unit for display on a device, wherein forming the text unit includes expanding each of the bounding boxes of the character targets horizontally by an extra border distance, the extra border distance calculated by a value α multiplied by the character height plus a border offset.
3. The method as claimed in claim 1 wherein generating the binarized image includes generating the binarized image of the source image where the source image is unstructured and cluttered, wherein an unstructured image includes textual elements with variations in size, font, style, stroke size, text color, and/or text background color, and a cluttered image includes text completely or partially overlaid on top of graphical elements.