Methods and systems for content-boundary detection

摘要

Aspects of the present invention are related to systems and methods for automatically determining the content boundaries in a digital image. A gradient field may be generated using an edge detector, and the gradient field may be thresholded, by magnitude, to retain strong edges. The resulting localized edge positions may be projected onto a first direction and a second direction to form two projection histograms. The projection histograms may be analyzed to determine the boundaries of the image content. Corners of a cropping rectangle may be computed, and the digital image may be cropped according to the content boundaries.

主权项

1. A method for content-boundary detection in a digital image, said method comprising:
determining the location of edges in a first image related to a digital image, thereby producing an edge map; receiving a skew parameter; determining a skew vector associated with said skew parameter; forming a first projection histogram of said edge map in a first projection direction, wherein said first projection direction is related to said skew vector; forming a second projection histogram of said edge map in a second projection direction, wherein said second projection direction is normal to said first projection direction; and determining a content boundary associated with said digital image using said first projection histogram and said second projection histogram.