Abstract: Computerized electro-optical system gages dimension of a moving hot bar. Back-lighted electronic camera head generates high-speed bar shadow pulses which represent the bar dimensions. Bar pulses are processed by way of camera electronics and a digital computer. CRT and printing terminals, interacting with the computer, indicate and/or record a field-of-view correction map and a cold-size bar diameter measurement.Camera head electronics includes camera AGC, a digital type one-axis bidirectional linear sweep, bar pulse edge-detection with an autocorrelator to remove noise and enhance the bar pulse, and a digital accumulator of digital bar size signals and digital bar position-in-field-of-view signals. The digital computer assimilates bar size and bar position signals along with bar temperature, aim size, and other data signals.