One of the features of my drone is that when recording video it can create external SRT subtitles containing stats (e.g. altitude / longitude / latitude etc.)
However, while it creates totally valid SRT files, these will not play in either Infuse on the iPad, or Apple TV. When playing, a subtitle will appear briefly for a fraction of a second, then disappear, and no further subtitles will appear. The also happens if you seek to a new location in the video.
There are 2 problems:
- the srt file is written with an uppercase SRT extension. Infuse won’t recognise these files as subtitle files at all. Changing the extension to lowercase srt fixes the issue.
- There appears to be a problem in Infuse with really short subtitles. The drone creates touching subtitles with a duration of 1/60th second each.
Here’s an example 2 subtitles:
00:00:06,752 → 00:00:06,769
SrtCnt : 406, DiffTime : 17ms
[iso : 100] [shutter : 1/400.0] [fnum : 280] [ev : 0] [ct : 5759] [color_md : default] [focal_len : 240] [latitude: 0.931526] [longtitude: -0.023676] [altitude: 114.500000]
00:00:06,769 → 00:00:06,786
SrtCnt : 407, DiffTime : 17ms
[iso : 100] [shutter : 1/400.0] [fnum : 280] [ev : 0] [ct : 5759] [color_md : default] [focal_len : 240] [latitude: 0.931526] [longtitude: -0.023676] [altitude: 114.400000]
If I increase the duration and change the file extension, then I can get the subtitles to play in Infuse. In fact, I wrote a script to fix up the subtitles to get them to work.
Are there some known limitations with short subtitle durations when using Infuse?