Investigations on bits on film high speed scanning device

Whereas the recording of digital data on film for long term storage can be realized with high speed the reading of those data by scanning devices still needs significant more time. Additionally to that it is crucial to realize a fast scanning of the recorded data for verification of the integrity of the data. This is actually the bottleneck in realizing a fast archiving production chain "bits on film". We describe here a new approach for a high speed scanning system, where a new frame grabber based electronics to generate a fast data reduction of the scanned data is used. The amount of data generated by a high resolution scanner with four times oversampling rate is enormous. In order to read the "bits on film" (information data) with a line-sampling rate of 100kHz the high speed scanner has to acquire data with a data rate of about 1,6 GByte/s. The challenge is to get the data amount reduced significantly already in the camera device without losing information. Therefor e the region of information has to be separated and the data reduction has to be done geometrically and in bit depth. We have built up a test scanning device to verify the principal usage and functionality of this approach We calculated that a data reduction rate of about 40 can be achieved. Although the focus of the test is on the fast data reduction we have to consider other requirements like the resolution of the optics, the lightning, the necessary oversampling rate, film transport accuracy and the structuring of the symbols on film. We experienced that the approach of reducing the amount of data from the scanned data down to the information data already in the scanning device is only possible if also other challenging specifications of the scanning system are realized there. We analyze in addition the necessary composition of the scanning device to realize a fast reading of the bits on film.