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Crop Smart

iPhone / iPad
  • Utilities
  • Photo & Video
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Have you ever wanted to crop a real world rectangular object from an image but found the cutting result is a quadrangle?

The difference is due to the perspective distortion caused by the camera's digital sensor not being parallel to the object's surface and/or not level with the center of the object. Sometimes it is unavoidable because of shooting situations or locations, sometimes it's for the visual effect. The distortion makes a real world rectangular object such as note book, poster, painting, whiteboard, business card, etc. appears to be a quadrangle in the image. Tradition cropping and transformation approach could not fix the distortion because everything is carried out in the 2D domain.

To fundamentally solve the problem, you need go 3D with Crop Smart. Based on advanced computer vision techniques, Crop Smart first estimates a set of parameters for the camera. It then uses the parameters to re-construct the real world object in 3D. The App simulates moving the camera to the parallel and central position which gives a perfect front view of the object. The geometry distortion will then be corrected automatically. The end result is a perfect rectangular and distortion free image containing the region you are interested in only.

To use Crop Smart, first load an image from photo album that contains a real world rectangular object you want to crop. You will see a red polygon overlay on top of the image. Adjust the polygon by moving its corners or edges so that it matches the object in the image. Then, click the "Crop" button to review the correction result. If you are satisfied with it, you can send it by email or save it to the album. Otherwise, click "Undo" button to go back re-adjust the red polygon.

For more information about Crop Smart, please visit our web site

Please make sure check out our App "OutColor". OutColor makes cool Out-of-bounds 3D effect from conventional 2D photographs.