“Photometric Camera Calibration: Precise, Labless, and Automated with AutoLum” by Olczak and Tumblin

  • ©Paul Olczak and Jack Tumblin

  • ©Paul Olczak and Jack Tumblin

  • ©Paul Olczak and Jack Tumblin



Entry Number: 78


    Photometric Camera Calibration: Precise, Labless, and Automated with AutoLum



    Even cheap camera phones can sense finer changes in luminance than the human visual system (0:2 – :5% steps vs. 1 – 2% JND), but noise and poor calibration limits their abilities to precisely measure light. This poster describes “AutoLum”, our fully automatic, software-only method that finds a camera’s photometric calibration, its “numbers-to-light amounts” table, with precision well beyond the camera’s own quantization levels. This table captures each quantization step and reveals correctable non-uniformities that allow more accurate results for almost any graphics or vision task that relies on pixel-by-pixel light estimates. These include HDR light probes, environment maps, estimates of material transparency and translucency, BRDF and BTF, or any 3D scanning method that relies on “shape from shading”. As shown in (Fig. 1), our method reduced angular errors in photometric stereo by 10x.


    1. Debevec, P. E., and Malik, J. 1997. Recovering high dynamic range radiance maps from photographs. In Proceedings of SIGGRAPH 97, ACM Press/Addison-Wesley Publishing Co., New York, NY, USA, SIGGRAPH ’97, 369378.
    2. Mann, S., and Picard, R. W. 1995. On being ‘undigital’ with digital cameras: Extending dynamic range by combining differently exposed pictures. In Proceedings of IS&T, 442448.
    3. Mitsunaga, T., and Nayar, S. 1999. Radiometric self calibration. In Computer Vision and Pattern Recognition, 1999. IEEE Computer Society Conference on., vol. 1, 2 vol. (xxiii+637+663).
    4. Robertson, M. A., Borman, S., and Stevenson, R. L. 1999. Estimation-theoretic approach to dynamic range enhancement using multiple exposures. Journal of Electronic Imaging 12, 2003.
    5. Woodham, R. J. 1980. Photometric method for determining surface orientation from multiple images. Optical Engineering 19, 1, 191139–191139–.


ACM Digital Library Publication:

Overview Page: