Image processing apparatus and image processing method
View Patent ↗When a detection-target subject is imaged with an image pickup device having line-defect pixels, the detection-target subject is imaged, with the image pickup device or the detection-target subject rotated at a predetermined angle so that the edge of one side of the detection-target subject is not parallel to each of horizontal and vertical scanning lines of the image pickup device, and a gray-scale image is captured by a control apparatus. In the gray-scale image, the luminance of each of the line-defect pixels is corrected by interpolation with luminances of pixels adjacent to both sides of the line-defect pixel. The gray-scale image is subjected to sub-pixel processing to detect the edge of the detection-target subject. When the detection-target subject is a component in a rectangular shape, rotation is made so that four sides are not parallel to each of the horizontal and vertical scanning lines of the image pickup device.
1. An image processing apparatus detecting an edge of a detection-target subject imaged by an image pickup device having line-defect pixels, the line-defect pixels being line defect(s) in one or both of a horizontal direction and a vertical direction, the apparatus comprising:
rotating motor configured to rotate the image pickup device or the detection-target subject; and
a control apparatus configured to:
image, in a single imaging, the detection-target subject with the image pickup device, with the image pickup device or the detection-target subject being rotated by the rotating motor at a predetermined angle so that the edge of the detection-target subject is not parallel to each of horizontal and vertical scanning lines of the image pickup device, and
detect the edge of the detection-target subject by performing sub-pixel processing on a gray-scale image obtained by performing correction by interpolation on a luminance of each of the line-defect pixels with luminances of pixels adjacent to both sides of the line-defect pixel based on the single imaging,
wherein when bumps of a Ball Grid Array-type component are taken as the detection-target subject and an edge of each of the bumps is detected, the control apparatus is configured to rotate at the predetermined angle so that an arrangement of the bumps in longitudinal, lateral, and diagonal directions of the Ball Grid Array-type component is not parallel to each of the horizontal and vertical scanning lines of the image pickup device.
2. The image processing apparatus according to claim 1 , wherein
when the detection-target subject is in a rectangular shape and edges of four sides of the detection-target subject are detected, the control apparatus is configured to rotate at the predetermined angle so that the four sides are not parallel to each of the horizontal and vertical scanning lines of the image pickup device.
3. An image processing method of detecting an edge of a detection-target subject imaged by an image pickup device having line-defect pixels, the line-defect pixels being line defect(s) in in one or both of a horizontal direction and a vertical direction, the method comprising the steps of:
imaging, in a single imaging, the detection-target subject with the image pickup device, with the image pickup device or the detection-target subject being rotated at a predetermined angle so that the edge of the detection-target subject is not parallel to each of horizontal and vertical scanning lines of the image pickup device; and
detecting the edge of the detection-target subject by performing sub-pixel processing on a gray-scale image obtained by performing correction by interpolation on a luminance of each of the line-defect pixels with luminances of pixels adjacent to both sides of the line-defect pixel based on the single imaging,
wherein when bumps of a Ball Grid Array-type component are taken as the detection-target subject and an edge of each of the bumps is detected, rotating at the predetermined angle so that an arrangement of the bumps in longitudinal, lateral, and diagonal directions of the Ball Grid Array-type component is not parallel to each of the horizontal and vertical scanning lines of the image pickup device.