• Digital Filtering Techniques for X-Ray Image Enhancement

      Hall, E. L.; University of Missouri-Columbia (International Foundation for Telemetering, 1971-09)
      Image enhancement techniques are designed to improve image quality for human viewing and are especially important in X-ray imaging systems since radiation levels must be minimized. Recursive spatial digital filtering and gray level transform enhancement techniques which may be implemented with small memory requirements and fast computation times will be described. A comparison of computations shows that this method is competitive with fast transform methods in terms of the number of computations and advantageous in terms of memory requirements. The most common method for evaluating enhancement results is subjective human evaluation. An experimental comparison of subjective evaluations and some objective measurements for a series of chest X-rays illustrate the evaluation problem and a possible solution.