Technical Q&A QA1447

Final Cut Pro X - Preferred Video Media Time Scales and Sample Durations

Q: When creating video for import into Final Cut Pro X, are there specific time scales and sample durations that should be used?

A: Yes, there are a number of preferred values.

As mentioned in the "QuickTime Image Rates and Video" section of Uncompressed Y´CbCr Video in QuickTime Files, a media has a time scale and each sample in a media has a duration. Together the duration and time scale specify the frame rate of the video.

When creating video media for Final Cut Pro X, the time scales and sample durations listed in Table 1 are the preferred values and should be used to accurately represent the frame rate of your content.

**Table 1** Preferred Final Cut Pro X Media Time Scales and Sample Durations.
Frames Per Second	Time Scale	Sample Duration		Time Scale	Sample Duration
59.94	60000	1001
50	5000	100	or	50	1
30	3000	100	or	30	1
29.97	30000	1001
25	2500	100	or	25	1
24	2400	100	or	24	1
23.976	24000	1001

30000/1001 is a more accurate representation of 29.97 fps and doesn't suffer the frame time deviation as discussed in 'Uncompressed Y´CbCr Video in QuickTime Files'. However, this does make a difference in duration. A media time scale of 30000 and media sample durations of 1001, along with a movie time scale of 30000, currently provides 19.9 hours of time while 2997/100 provides 8.2 days of time.

Reference:

QuickTime Image Rates and Video - Uncompressed Y´CbCr Video in QuickTime Files

Table 2 contains a list of legacy Media Time Scales and Sample Durations values for reference purposes.

**Table 2** Legacy FCP Media Time Scales and Sample Durations.
Frames Per Second	Time Scale	Sample Duration		Time Scale	Sample Duration
60	6000	100	or	60	1
59.94	5994	100
50	5000	100	or	50	1
30	3000	100	or	30	1
29.97	30000	1001	or	2997	100
25	2500	100	or	25	1
24	2400	100	or	24	1
23.98	23976	1000

Document Revision History

Date	Notes
2014-08-26	Updated table for FCP X
2005-10-24	New document that lists the preferred time scales/sample durations for media created for use with FCP.