Method for reconstructing a curved surface of a subject and an apparatus for reconstructing a curved surface of a subject

A method for reconstructing a curved surface of a subject, comprising the steps of

• (a) photographing a subject from at least two different positions and detecting each gradational image seen from each of the respective positions,
• (b) computing a luminance ratio of pixels corresponding to each other in said different gradational images, and
• (c) reconstructing a curved surface of said subject through computing an inclination of the surface of said subject on the basis of the luminance ratio, wherein;
• said step (b) including the steps of;
• (b-1) setting one of said gradational images as a reference image, setting as the first pixel one pixel corresponding to an observed part of said subject out of a number of pixels arranged in a matrix forming this reference image, and detecting the first luminance of the first pixel,
• (b-2) setting, as the origin pixel, one pixel corresponding to said observed part out of a number of pixels arranged in a matrix forming said one gradational image different from said reference image, setting the second pixel a pixel distant by the first offset from this origin pixel, and detecting the second luminance of the second pixel,
• (b-3) setting, as the third pixel, a pixel which is on the straight line drawn through said origin and said second pixel and is at the opposite side to said second pixel in relation to said origin pixel and is distant by the second offset from said origin pixel, and detecting the third luminance of the third pixel,
• (b-4) obtaining the first luminance ratio of said first luminance and said second luminance, and
• (b-5) obtaining the second luminance ratio of said first luminance to said third luminance, and furthermore
• said step (c) including the steps of;
• (c-1) a step of reconstructing a curved surface of said subject through computing a surface inclination of said subject on the basis of said first and said second luminance ratio.

An apparatus for reconstructing a curved surface of a subject, comprising

• an image detecting part for detecting plural gradational images by photographing a subject from at least two different positions;
• and
• a curved surface reconstructing part for computing a luminance ratio of pixels corresponding to each other in the detected gradational images different from each other and reconstructing a curved surface of said subject through computing a surface inclination of said subject on the basis of this luminance ratio,
• said curved surface reconstructing part comprising;
• a first luminance detecting part for setting one of said plural gradational images as a reference image, setting as the first pixel one pixel corresponding to an observed part of said subject out of a number of pixels arranged in a matrix forming said reference image, and detecting the first luminance of said first pixel,
• an origin pixel setting part for setting as the origin pixel one pixel corresponding to said first pixel out of a number of pixels arranged in a matrix forming said one gradational image different from said reference image,
• a second luminance detecting part for setting as the second pixel a pixel distant by the first offset from said origin pixel and detecting the second luminance of said second pixel,
• a third luminance detecting part for setting as the third pixel a pixel which is on the straight line drawn through said origin and said second pixel and is at the opposite side to said second pixel in relation to said origin pixel and is distant by the second offset from said origin pixel, and detecting the third luminance of the third pixel,
• a first luminance ratio computing part for obtaining the first luminance ratio of said first luminance and said second luminance,
• a second luminance ratio computing part for obtaining the second luminance ratio of said first luminance and said third luminance, and
• a depth detecting part for reconstructing a curved surface of said subject on the basis of said first and said second luminance ratio.