Python 2.x will also do it automatically with integer types, but it can be forced to do it with a / / symbol, which is required in Python 3.x. Ruby will also do it automatically with integers and it can be forced with Numeric#div. It looks like \ the operator comes from the BASIC world. Different languages do different things when doing integer division with negative numbers. Some round towards zero, others round down. That’s beyond the scope of this tutorial, though. I’m using the symbol % to represent the modulo operator.
Modulo refers to the remainder that’s left after division.
30 / 7 is 4 with a remainder of 2, so 30 % 7 would be 2. Most languages use the same % notation for modulo. As with integer division, modulo behaviors vary among programming languages when negative numbers are involved.
Again, we’re not going to worry about those distinctions here. In NTSC countries, 24p footage actually runs at 23.976 fps. 23.976 drop-frame timecode is not part of the SMPTE timecode spec and most editing programs don’t have a 24p drop-frame option. Let’s think about how drop-frame timecode works for 29.97. However, since NTSC video operates at 29.97, not 30 frames per second, the actual number of frames in ten minutes of NTSC video is:Ģ9.97 (frames per second) * 60 (seconds per minute) * 10 (minutes) = 17,982 In fact, drop-frame is cyclical every ten minutes and, therefore, is guaranteed to accurately represent run-time every ten minutes.Īt 30 frames per second, to convert ten minutes of programming to a frame count, you multiply:ģ0 (frames per second) * 60 (seconds per minute) * 10 (minutes) = 18,000 Television programs commonly run in 30 minute increments, so drop-frame timecode should work in such a way that it is guaranteed to be a correct representation of the running time at least every 30 minutes. That means that every ten minutes, drop-frame timecode needs to make up for the discrepancy between 18,000 frames and 17,982 frames, which is 18 frames.
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