Error Code:
ANALYZER-TelecineDetected (Telecine Detected)
Error Message:
Telecine=true NTSC: [Top 0.4287, 0.7259, 0.5906...]
Definition:
Our tools have detected a pulldown pattern that suggests the content is not in its native frame rate.
The inspection looks at both the top and bottom set of fields within the video (Top/Bottom) and provides 3 sets of numbers.
3rd number: The percentage of frames in the video that were usable for the test (i.e. scenes with motion)
2nd number: The percentage of the usable frames which were affected.
1st number: The overall percentage of the entire video that we believe to be affected by telecine.
We can detect both 3:2 and 4:1 pulldown patterns.
3:2 Pulldown: In a sequence of 5 frames you will see 3 progressive and 2 interlaced frames. The pattern (or cadence) repeats throughout the entire program. Occasionally the cadence can be broken, usually due to an edit being performed after the pulldown has been applied.
4:1 Pulldown: In a sequence of 5 frames you will see 5 progressive frames, but the 4th and 5th frame with be identical. Likely caused when material with a 3:2 pulldown pattern has been deinterlaced.
Solution:
If 3:2 pulldown is present an inverse telecine must be performed. All transcoders provide this as a filter. Depending on your transcoder there may be an option to enable the detection of broken cadence. Enable this setting so that the encoder can adapt if the pattern of the pulldown breaks at any point. This will create a 23.98/24fps master with only progressive (and unique) frames.
If 4:1 pulldown is present attempt to locate the original file with 3:2 pulldown and perform an inverse telecine. In the event you are unable to access the original, you can push the file through Cinnafilms Tachyon which can detect and remove 4:1 pulldown. In the end you should end up with a 23.98/24fps master with no duplicate frames.