A method for operating a thermal transfer printer includes providing a ribbon, providing at least one spool configured to take up the ribbon, and providing a printhead. The substrate is moved relative to the printhead at a speed. The ribbon is moved relative to the printhead at a speed that is less than the speed of the substrate while using the printhead to selectively transfer ink from the ribbon to the substrate to print an image on the substrate. Data is captured from the ribbon after ink has been transferred to the substrate. The data is processed to control at least one property of the printer.

Techniques are described for printing on front and back surfaces of security document substrates in a manner that conserves use of print ribbon, thereby extending the life of the print ribbon. In general, the printer controller knows the content, as well as locations and colors, of what has been printed on the front or first surface of the security document substrate. The printer control also knows the content, as well as locations and colors, of what is to be printed on the back or second surface of the security document substrate. When the back surface of the substrate is to be printed, the printer controller determines, for a particular color, whether any of the printing on the back surface would overlap with the printing on the front surface. For locations where there would be no overlap, the printer can reuse the section of print ribbon that was used to print on the front surface to print on the back surface.

Techniques are described for printing on front and back surfaces of security document substrates in a manner that conserves use of print ribbon, thereby extending the life of the print ribbon. In general, the printer controller knows the content, as well as locations and colors, of what has been printed on the front or first surface of the security document substrate. The printer control also knows the content, as well as locations and colors, of what is to be printed on the back or second surface of the security document substrate. When the back surface of the substrate is to be printed, the printer controller determines, for a particular color, whether any of the printing on the back surface would overlap with the printing on the front surface. For locations where there would be no overlap, the printer can reuse the section of print ribbon that was used to print on the front surface to print on the back surface.

The disclosure discloses a printer including a memory. The memory stores computer-executable instructions that, when executed by a processor, cause the printer to perform a first process, a second process, and a third process. In the first process, an N-th determination target value is calculated, from an N-th pulse count index value and an (N+1).sup.th pulse count index value. In the second process, a mean value of a plurality of consecutive pulse count index values within a predetermined range is calculated. In the third process, a comparison value is calculated by comparing (N1).sup.th the determination target value with the mean value. The first process to the third process are performed while increasing N one by one. A first determination step includes determining whether the elongated medium has reached a consumption completion status or not, on the basis of a magnitude relation between the comparison value and a first threshold value.

The disclosure discloses a printer including a memory. The memory stores computer-executable instructions that, when executed by a processor, cause the printer to perform a first process, a second process, and a third process. In the first process, an N-th determination target value is calculated, from an N-th pulse count index value and an (N+1).sup.th pulse count index value. In the second process, a mean value of a plurality of consecutive pulse count index values within a predetermined range is calculated. In the third process, a comparison value is calculated by comparing (N1).sup.th the determination target value with the mean value. The first process to the third process are performed while increasing N one by one. A first determination step includes determining whether the elongated medium has reached a consumption completion status or not, on the basis of a magnitude relation between the comparison value and a first threshold value.

Techniques are described for printing on front and back surfaces of security document substrates in a manner that conserves use of print ribbon, thereby extending the life of the print ribbon. In general, the printer controller knows the content, as well as locations and colors, of what has been printed on the front or first surface of the security document substrate. The printer control also knows the content, as well as locations and colors, of what is to be printed on the back or second surface of the security document substrate. When the back surface of the substrate is to be printed, the printer controller determines, for a particular color, whether any of the printing on the back surface would overlap with the printing on the front surface. For locations where there would be no overlap, the printer can reuse the section of print ribbon that was used to print on the front surface to print on the back surface.