Of the four basic medical diagnoses in Chinese medicine, tongue examinations rank in importance with pulse examinations. The conventional method of clinically recording the color of the tongue by taking photographs with film cameras generally presents various problems, such as the difficulty of establishing objective procedures and the long-term storage of records.
The authors accordingly attempted to enhance the objectivity of tongue examinations by devising a new image correction procedure combining the use of color-and-size-matching stickers (image correction color charts) and computers utilizing a digital camera. As a result, the images that are output after correction not only reproduce the tongue in its actual size but also make it possible to approximate color system values measured from the actual tongue, thereby suggesting the possibility of a useful procedure for making objective evaluations in tongue examinations.