Subtitle timings are off after export a specific clip

[James353365324886]

I have a long video that I break up in to smaller clips - essentially chapters. 

When I am exporting these out, the subtitle SRT timestamps align with the full original video, not the specific clip I have extracted and therefore do not match up at all.

I can't find a way to fix this.

For example, lets say I have a 15 minute video and I am wanting to export the middle 5 minutes, the time stamps in the SRT file will start at 00:05:00:00 in relation to the full video as opposed to starting at 00:00:00:00 in alignment with the actual clip I have exported.

This seems really silly and I am possibly missing something obvious but are unable to work out why it will not align the timestamps to the extracted clip.

[Stan Jones]

@James353365324886,

You can submit an Idea/feature request, but it is really working as designed. This question was asked in 2021 not long after the new caption workflow was introduced, but I don't see a feature request.

Yes, when setting in/out markers to export part of a sequence, the sidecar export will keep the timecodes from the sequence, not the in/out segment starting at zero.

I see 2 workarounds.

1 - Use a third party tool to edit the srt and adjust the timecodes so they start at zero.

2 - Once the sequence is done and ready for exports, duplicate the sequence, set the first out point, and export with sidecar. Then, for each export file segment, target all layers (including captions if you are cutting mid-caption), and cut the video at that "old" out point.  Drag select all the tracks and captions from the previous export, and ripple delete. Then set the new out point and repeat. The exports will all start at zero.

Does that work for you as a workaround?

Stan

[James353365324886]

Thanks Stan. I'll definately put that forward as a suggestion because it does seem odd it does work correctly and timestamps do not align.

As for the work arounds - they are what I already suspected but was hoping there would be an actual solution or a more efficient way. Across 3 videos we're probably talking 50+ exports, they all then have to be re-uploaded individually so reality is a lot of work to make them correct using workarounds. I may just have to exlcude the subtitles or chip away at them bit by bit. 

Appreciate you commenting though and confirming that I am not missing something obvious.

[Stan Jones]

@James353365324886,

Right; nothing optimal so far. I explored workaround 1 a bit more. My favorite app is SubtitleEdit. Results below, but quick bottom line: not really an improvement over workaround 2 - unless you already had all your exports. - and maybe not then.

@Mathias Moehl I'm not finding the time the play with Automation Blocks as I would like. Manipulation of captions can be tricky, but what James needs is a method of exporting multiple in/out sections with the sequence time at the in point set to zero for each export. Is that in the library already?

BTW, James, another workaround I tried was resetting the sequence start time for each in/out export, but you can't use a negative.

Subtitle Edit method:

In/out set so that In is 00:12:02. First caption after the in point is 12:11, 9 frames after the beginning of the clip to be exported. Export in/out with sidecar.

To confirm the problem, import the exported clip to PR, make sequence, and confirm that clip starts at zero. Import captions from file using source time, and confirm first caption is at 12:10 - as expected and wrong.

The SRT needs to have its first caption timecode at 00:09. But SRTs use milliseconds, not frames, so assuming 29.97 time, (9/29.97) * 1000 = 300.3.

Open the SRT in Subtitle Edit. The first caption starts at 00:12.375. To make that 00.300, we need to make it 12.075 earlier. So, Synchronization -> Adjust All Times. Enter 12.075, then click "show earlier." You will see the times change. X out the synchronization window. Save the file.

To confirm the fix, import the exported clip to PR, make sequence, and confirm that clip starts at zero. Import captions from the SE edited file using source time, and confirm first caption is at 00:09 - correct and in sync for the whole clip.

Stan

[Mathias Moehl]

How exactly do you determine which parts of the sequence you export?

I just wrote a tool for the Community Library of Automation Blocks Pr for you, which applies an offset to a single SRT file:

File Handling/SRT/Add Time Offset to SRT File.xml

Just load the xml block script into Automation Blocks and in the inputs panel choose
- an input SRT file

- an output SRT file 
- a time offset in seconds
Then run the tool and it will create the output SRT file with the desired time offset.

If you want to create some kind of batch processing to manipulate many SRT files at once, the script will be a good starting point (as any Automation Blocks tool, it can be fully customized). Main question for further automation is how the tool should know the names of the different files and their offsets (maybe you have those in a spreadsheet or you have markers in your timeline with that info, for example).

[James353365324886]

Thank you Stan and Mathias. I'll take a look into this.

In my scenario, all the SRT files have been exported but other than the first video there is a long pause/offset from 00:00:00:00 until the subtitles start in alignment with the master video, lets say 00:05:00:00. So in an ideal world, it would look at what that first gap is, and then essentially deduct that amount of time from every timestamp. So 00:05:00:00 would become 00:00:00:00 and so on.

As I say, I'll have a look at your tool later today or tomorrow when I have some time.

[Stan Jones]

@James353365324886,

> So in an ideal world, it would look at what that first gap is, and then essentially deduct that amount of time from every timestamp.

I think that is what he has done.

@Mathias Moehl,

As always, the power of Automation Blocks is fascinating to me. "Add Time Offset to SRT File.xml" will be useful to other users - and it will fix James' srts. I assume that what James would most like going forward would be a method for exporting the SRTs so the timecodes are correct on export.

Stan

[Mathias Moehl]

In the Automation Blocks tool mentioned above, you have to enter the time offset manually in the inputs panel.

If you want the time offset to always be exactly such that the first title text starts at 0, then you can use the following tool I just wrote for you:

File Handling/SRT/Offset SRT Time to Start at 0.xml

(also now in the Community Library)

It works very similar,  but this time, you just enter a input and output file and the offset is calculated automatically such that the SRT starts at 0: