Method of image joining for scanner

A scanning method comprising:

• scanning first image data with a first photodetector moving in a first direction;
• stopping the first photodetector;
• scanning first position data with a second photodetector after stopping the first photodetector:
• moving the first photodetector and the second photodetector in a second direction opposite the first direction;
• scanning second image data with the first photodetector moving in the first direction and scanning second position data with the second photodetector moving in the first direction;
• comparing the second position data with the first position data to determine a joining point;
• and
• joining the first image data and the second image data at the joining point.

A scanning method comprising:

• scanning first image data;
• storing the first image data in a register;
• suspending the scanning of the first image data in response to a first condition of the register;
• scanning first position data while the scanning of the first image data is suspended;
• simultaneously scanning second image data and second position data in response to a second condition of the register that is different from the first condition;
• determining an image data joining point based on a match between the second image data and the first image data;
• and
• joining the first image data and the second image data at the image data joining point.

An apparatus including a computer-readable medium having instructions stored thereon that, if executed by a scanner, cause the scanner to perform operations comprising:

• scanning first image data with a first photodetector moving in a first direction;
• stopping the first photodetector and scanning first position data with a second photodetector;
• moving the first photodetector and the second photodetector in a second direction opposite the first direction;
• scanning second image data with the first photodetector moving in the first direction and scanning second position data with the second photodetector moving in the first direction;
• comparing the second position data with the first position data to determine a joining point;
• and
• joining the first image data and the second image data at the joining point.

A scanner comprising:

• means for scanning first image data in a first direction;
• means stopping the means for scanning first image data;
• means for scanning first position data while the means for scanning first image data is stopped;
• means for moving the means for scanning first image data and the means for scanning first position data in a second direction opposite the first direction;
• means for scanning second image data in the first direction;
• means for scanning second position data in the first direction;
• means for comparing the second position data with the first position data to determine a joining point;
• and
• means for joining the first image data and the second image data at the joining point.