Data-bearing halftone images are an attractive high-capacity alternative to barcodes. We show that smartphone close-focus video capture can recover the associated data, and a frequency-domain-based algorithm enables a robust means of detecting the presence as well as determining the location, scale, and orientation of data-bearing designs. Android and iOS mobile implementations achieve this at near video rates. Using these affine transform parameters as a starting point, a method for full perspective correction for precise alignment is also developed. This functionality is fast, accurate, and achieved without the benefit of fiducial marks.