Method for controlling image reader
OwnerKiyoto Kosakainventor
Life of this patent
Estimating the term…
Abstract
A method for controlling an image reading apparatus (100) performs an auto focus process for adjusting the focus on a medium (300) surface and a reading process for reading an image on the medium (300) at the focus adjusted by the auto focus process. During the auto focus process, a difference processing unit (5) calculates differences between adjacent picture elements in image data read from the medium (300), an averaging processing unit (6) averages the differences, and a midpoint processing unit (7) slices characteristic data obtained from the averaging processing into a plurality of region to determine the midpoint in each region, so that the focal point can be calculated.
Claims15
A method for controlling an image reading apparatus, the method comprising:
- performing an auto focus process to adjust a focus on a surface of a medium;
- and
- performing a reading process to read an image on the medium at the focus adjusted by the auto focus process,
- wherein the auto focus process further comprises:
- performing a shading compensation process on image data read from the medium;
- performing a gamma correction process on the shading-compensated image data;
- calculating differences between adjacent picture elements in the gamma-corrected image data;
- averaging the differences;
- and
- obtaining characteristic data from the averaging process is sliced into a plurality of region and determining the midpoint in each of the plurality of region, so that the focus is calculated.
A method for controlling an image reading apparatus, the method comprising:
- performing an auto focus process to adjust focus on a surface of a medium;
- and
- performing a reading process to read an image on the medium at the focus adjusted by the auto focus process,
- wherein the auto focus process further comprises:
- performing a shading compensation process on image data read from the medium, using a lamp which has flat output characteristics in the main scanning direction as a light source, and
- wherein the reading process further comprises:
- performing a compensation process on image data read from the medium again, using shading data resulting from the shading compensation process performed in the auto focus process.
A method for controlling an image reading apparatus, the method comprising:
- performing an auto focus process to adjust focus on a surface of a medium;
- and
- performing a reading process to read an image on the medium at the focus adjusted by the auto focus process,
- wherein the auto focus process further comprises:
- performing a gamma correction process on image data read from the medium, using a first gamma table stored in a first gamma buffer;
- and
- wherein the reading process further comprises:
- performing a gamma correction process on the image data read from the medium again, using a second gamma table stored in a second gamma buffer.
Dependencies are inferred from the claim text.