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CPP100
SECTION 6
CPP1OPS
25/10/06
www.snellwilcox.com
Version 1 Issue 6
6.15
Film / Video Identification
Film is scanned directly to produce a 625 line 50Hz output by running the telecine at 25/24 normal speed. The
resulting output has pairs of fields corresponding to each original film frame. No additional fields are required,
as the resulting frame rate of 25Hz is exactly correct for the 625 line standard. The frame pairs are identified
by analysis of field differences.
Film originated material has a high level of picture correlation on fields which are extracted from the same film
frame. Processed picture differences will produce a characteristic frame rate output signal as shown below.
Correlation algorithms within ‘Prefix ‘ are used to extract the film sequence and identify the source as film
originated.