1. A system for identifying a first tissue boundary and a second tissue boundary in a test ultrasound image, said second tissue being of a different tissue type than said first tissue, the system comprising: an input for receiving said test ultrasound image; a data processing device configured to process said ultrasound image according to the following steps: (i) generate an intensity histogram from pixel intensities of said test ultrasound image, said intensity histogram having peak regions corresponding to regions of intensity peaks in said test ultrasound image, (ii) calculating a series of stand-alone features for each peak region of the intensity histogram, said stand-alone features being determined from local-peak characteristics of each peak region and lacking any relational correlations between the first and second tissue boundaries; a first classifier coupled to receive said stand-alone features, said first classifier being trained to identify said first tissue boundary using only said stand-alone features and omitting any relational information between boundaries of different tissue types, said first classifier outputting a first boundary estimate; a second classifier coupled to receive said stand-alone features and said first boundary estimate, said second classifier being trained to identify said second tissue boundary using said stand-alone features and a first specified location of said first tissue boundary, said second classifier using said first boundary estimate as said first specified location, and outputting a second boundary estimate; a third classifier coupled to receive said stand-alone features and said second boundary estimate, said third classifier being trained to identify said first tissue boundary using said stand-alone features and a second specified location of said second tissue boundary, said third classifier using second boundary estimate as said second specified location, and outputting a third boundary estimate; identifying said third boundary estimate as said first tissue boundary in said test ultrasound image, and identifying said second boundary estimate as said second tissue boundary in said test ultrasound image.