High Dynamic Range Images from Multiple Exposures Lukas Cerman Center for Machine Perception Faculty of Electrical Engineering CTU Prague (diploma student, advisor V. Hlavac) Center for Machine Perception, Faculty of Electrical Engineering, CTU Prague The limited dynamic range of a camera may be extended by composing differently exposed images of the same scene. The nonlinear camera has to be calibrated radiometrically first. We present several state of the art calibration methods and show that the calibration process can be difficult for real cameras. The problems with calibration can be overcome if linear 12-bit RAW images are used as offered by modern mid-class and professional cameras. Another aspect affecting the radiometric quality of the composed high dynamic range (HDR) image is the knowledge of exposure times. This knowledge also helps in registration of differently exposed hand held shots. We present a new method for estimating exposure times from the histograms of images captured using a linear response camera or generated from a RAW image. The actual process of HDR image composition needs perfectly aligned images on its input. We present a method for registering differently exposed images captured with a hand held camera. The presented registration method enables capture of HDR images without the need of mounting a camera on the tripod. We will also briefly discuss the composition of grayscale HDR image from color photographs.