1. A method for image acquisition, said method comprising: obtaining a preview-frame image; extracting a first image feature from said preview-frame image, wherein said extracting said first image feature comprises: determining a top-boundary line of a document region; determining a bottom-boundary line of said document region; determining a left-boundary line of said document region; determining a right-boundary line of said document region; determining a horizontal vanishing point; determining a vertical vanishing point; determining a first distance between said horizontal vanishing point and a center point associated with the center of said preview-frame image; and determining a second distance between said vertical vanishing point and said center point; interpreting said first image feature in relation to a first acquisition factor; and rendering an overlaid preview-frame image comprising a first cue associated with said first acquisition feature.