How to get captions out of Avid Media Composer as SRT

Getting subtitles out of Avid Media Composer as an SRT is a two-step move: export the caption data from the SubCap effect as a TXT file, then convert that TXT into SRT. Media Composer has no "Export as SRT" button for SubCap subtitles — the effect speaks its own timecoded caption format — so the conversion step is where the SRT actually gets made. This guide covers the export, the conversion, and the one timecode surprise that catches almost everyone.

Already have the TXT? Drop it on the free Avid TXT to SRT converter and download a clean, timed .srt — speaker labels and line breaks preserved, batches returned as one ZIP.

Step 1: Export the caption data from Media Composer

The captions live inside the SubCap effect on your timeline, and they come out the same way they went in — through the effect's own file tools:

1. Park on the SubCap effect segment and enter Effect Mode (or open the Effect Editor with the segment selected).
2. Expand the Caption Files group in the SubCap parameters.
3. Click Export Caption Data and save the .txt file.

If the sequence has more than one caption track — a subtitle track and a forced-narrative track, say, or one track per language — each SubCap effect exports its own TXT. Export them all and convert them as a batch.

What the export looks like

The exported file is Avid's caption TXT format: caption blocks between <begin subtitles> and <end subtitles> markers, each block a start/end timecode pair followed by the caption text.

<begin subtitles>

01:00:01:00 01:00:03:12
Welcome back to the show.

01:00:03:13 01:00:06:00
Today we're talking about captions.

<end subtitles>

The timecodes are HH:MM:SS:FF — the last field is a frame count, which is the core difference from SRT's millisecond timestamps (00:00:03,433) and the reason a straight rename never works.

Step 2: Convert the TXT to SRT

1. Open the Avid TXT to SRT converter.
2. Drop the exported .txt files — several at once if you exported multiple tracks.
3. Download the .srt (or the ZIP for a batch). Each caption block becomes a numbered SRT cue with the timecode re-expressed in milliseconds.

The result is a standards-compliant SRT that uploads to YouTube and Vimeo, loads into any media player, and imports into other NLEs — Premiere Pro reads SRT as captions directly, and if you need it in Premiere's transcript panel instead, run the SRT through the transcript JSON workflow.

The timecode surprise: sequences that start at 01:00:00:00

Broadcast sequences usually start at hour one, and the exported caption data carries those absolute timecodes — so the converted SRT's first cue starts at 01:00:01,000, not one second in. Players and platforms that expect zero-based subtitles will show nothing for the first hour.

If your delivery target expects subtitles timed from zero (YouTube does), fix it at the source: before exporting, work from a copy of the sequence with the start timecode set to 00:00:00:00 (edit the Start column for the sequence in the bin), or retime the SRT afterward in a subtitle editor. If the SRT is going back into another timeline that also starts at hour one, leave it alone — the absolute timecodes are exactly what you want.

Troubleshooting

• The converter finds no captions. Open the TXT and confirm the <begin subtitles> / <end subtitles> markers are intact and each block is a timecode pair followed by text. A file exported mid-edit with zero captions converts to nothing.
• Cues are subtly early or late. The frame field is being interpreted at a different frame rate than the sequence used. Sub-second offsets that grow over the runtime are the giveaway — reconvert rather than nudging cues.
• Multiple languages in one export. SubCap exports one file per effect, so languages stay separate — convert each TXT to its own SRT and name them accordingly (show.en.srt, show.fr.srt).

Going the other direction — you have an SRT and need it in Media Composer — is the mirror workflow: convert the SRT to Avid caption TXT and import it through SubCap. For Avid's broadcast closed-caption pipeline (SCC/MCC rather than SubCap subtitles), start from Avid's Media Composer documentation.

FAQ

Can Media Composer export SRT directly? Not from the SubCap effect — its Export Caption Data writes Avid's own caption TXT format. Converting that TXT is how you get a real SRT with millisecond timing.

Where is Export Caption Data? In the SubCap effect's parameters: select the effect segment, enter Effect Mode, expand the Caption Files group, and the Export Caption Data button is next to Import Caption Data.

Will the SRT timing match what I saw in Avid? Yes — each caption's start and end timecode is read from the export and re-expressed in SRT's millisecond format. The one thing to watch is a sequence that starts at 01:00:00:00, which carries that hour offset into the SRT.

Why does my SRT start at one hour? Because the sequence did. Avid exports absolute timecodes, so an hour-one sequence start becomes an hour-one first cue. Export from a zero-based copy of the sequence, or retime the SRT, if your platform expects subtitles from zero.

Can I convert the SRT back into Avid later? Yes — the SRT to Avid TXT converter rewrites SRT cues into caption TXT at the frame rate you choose, ready for SubCap's Import Caption Data. The round trip preserves text and timing.

How many files can I convert at once, and what does it cost? Free to start. Guests convert up to 3 files per batch at up to 1 MB each; a free account raises that to 5 files and 30 conversions a month, and paid plans support 20 MB files and larger batches — batches come back as a single ZIP.