How to Convert SUP or PGS to SRT with Subtitle Edit

How Subtitle Edit Converts Image Based PGS into SRT Text

PGS captions are bitmap images, not stored words. A .sup file commonly contains an extracted Blu-ray PGS stream with subtitle images and timing data. Subtitle Edit reads those images, applies OCR and lets you save reviewed text as SRT.

OCR can confuse similar characters, stylized punctuation and outlined glyphs. SRT stores timed text and cannot reproduce every visual feature of PGS. For the format background, read what PGS subtitles are.

Subtitle Edit or an Online SUP to SRT Converter?

If you want the fastest path without installing a desktop editor, use the online SUP to SRT converter.

Before You Import the SUP File

• Obtain the .sup file legally and with permission to process it.
• Confirm that it is a Blu-ray PGS subtitle stream, not an unrelated file merely named .sup.
• If the PGS track is embedded in an MKV, extract it first or use a supported import path in your installed Subtitle Edit version.
• Install a current stable release from an official source.
• Ensure the OCR language data needed for the subtitle's script is available.
• Keep the original SUP file as a backup.
• Know the intended output language and target player.

Use the official Subtitle Edit website or the current official Subtitle Edit releases. Do not rely on unofficial installer mirrors. Recent official release assets include packages for Windows, macOS and Linux, but exact packaging, requirements and feature availability can change by release.

Extract the PGS Track First When Needed

If the PGS subtitle is embedded inside an MKV, a current Subtitle Edit build may offer a supported import route from the container. For a predictable reusable workflow, you can first extract the selected PGS track as a standalone SUP file with FFmpeg or MKVToolNix and then open that SUP file in Subtitle Edit.

• Extract PGS subtitles with FFmpeg.
• Extract PGS with MKVToolNix.
• Read the complete SUP/PGS extraction guide.

Step 1. Import the Blu-ray SUP Subtitle into Subtitle Edit

1. Open Subtitle Edit.
2. Use the current File menu command for importing or opening an image based Blu-ray SUP subtitle.
3. Select the .sup source file.
4. Confirm that Subtitle Edit opens its image based subtitle OCR interface or equivalent workflow.
5. Check that subtitle images and timings appear before starting recognition.

In some Subtitle Edit versions, opening a SUP file directly launches the Import/OCR window. In others, use the File menu's Import/OCR command for Blu-ray SUP or image based subtitles. Follow the equivalent label in your installed release, and use the official Subtitle Edit help for version-specific details.

What to verify in the import window

• The correct source file is open.
• Subtitle image previews are visible.
• Cue timing information is present.
• The number of entries is plausible for the intended full or forced track.
• The selected track language matches the desired subtitle content.

Step 2. Choose an OCR Method

Available methods depend on the installed version, platform, downloaded components and configuration. Start with a locally available OCR method that supports the subtitle language. Test a representative group of captions, then switch methods if the error pattern is consistently poor. No single OCR engine is best for every script, font and source.

Tesseract

Tesseract is an open-source OCR engine used by Subtitle Edit workflows. It can recognize many languages when the appropriate trained language data is available. Results vary by script, font, outline, resolution and subtitle image quality.

Binary image compare or nOCR-style recognition

Image-comparison methods can learn or match recurring glyph images. They may work well when a subtitle track repeatedly uses a consistent font and style, but they may require user confirmation or a suitable database.

Other available engines

Current Subtitle Edit releases can evolve and may expose additional OCR methods. If an option requires downloaded components or an external service, check the current documentation and understand whether subtitle images leave your machine before using it.

Step 3. Select the Language Shown in the Subtitles

Select the language of the visible subtitle text. The film's spoken language may differ from the subtitle language. Choosing the wrong OCR language can damage accents, punctuation, word recognition and character segmentation.

• Japanese audio with English subtitles requires English recognition data.
• English dialogue with Spanish subtitles requires Spanish recognition data.
• A track containing English plus occasional Japanese signs may require manual correction even with the main language selected.

Multilingual tracks may need extra manual review or more than one pass, depending on the tool's capabilities. Missing language data may need to be installed or downloaded through an official Subtitle Edit-supported route.

Step 4. Run OCR and Correct Recognition Errors

1. Start OCR using the selected method.
2. Compare the source subtitle image with the proposed text.
3. Correct unknown or suspicious words.
4. Use replace-all or add-to-dictionary actions only when the same correction is valid throughout the file.
5. Preserve intentional capitalization, accents and speaker markers.
6. Continue until all cues have been processed.

Use global replacements carefully. A correction that is valid in one word may be wrong elsewhere. Review enough examples before applying it to the entire subtitle.

Adding a real recurring name or word can reduce repeated prompts. Do not add a misspelling merely to dismiss a warning. Names, invented terms and transliterations deserve manual verification.

Step 5. Review Text, Timing and Formatting

Text review

• Spell-check the correct language.
• Read every flagged or uncertain cue.
• Check names, places, technical terms and contractions.
• Check punctuation, quotation marks and apostrophes.
• Remove recognition artifacts that were not present in the subtitle.

Line-break review

Rewrap awkward lines created by OCR and keep the text readable for the target player. Avoid a line break that separates an article, preposition or short name unnaturally where practical.

Timing review

Imported PGS cues normally provide existing timing information. Do not automatically shift or retime the entire subtitle. Preview against the matching video if available and correct actual overlaps, extremely short durations or synchronization problems only after verifying them.

Formatting review

SRT has less styling and positioning capability than image based PGS. Font, color and exact screen position will not transfer perfectly. Re-add meaningful italics or labels where needed, and choose a richer text subtitle format only if layout is essential.

Step 6. Save as SubRip SRT with UTF-8 Encoding

1. Choose SubRip as the output format.
2. Use Save As rather than overwriting or confusing the source file.
3. Give the file a clear .srt name.
4. Choose UTF-8 for broad character support unless a known target device requires a different encoding.
5. Reopen the saved SRT and test it with the intended video or player.

Changing only .sup to .srt is not conversion. Subtitle Edit must OCR the subtitle images and save a new text subtitle file.

1
00:00:12,500 --> 00:00:15,200
This is recognized subtitle text.

2
00:00:16,100 --> 00:00:18,600
Review punctuation and names before publishing.

Final Quality Checklist

• The output format is SubRip SRT.
• The file is saved separately from the original SUP.
• UTF-8 or the required target encoding is selected.
• Uncertain OCR words have been reviewed.
• Names, punctuation, accents and speaker labels are correct.
• Line breaks are readable.
• Timing has been tested against the matching video.
• Important italics or signs have been handled manually.

If the finished SRT is for a media server, check the Plex guide or the Jellyfin guide for external subtitle naming.

Troubleshooting Subtitle Edit SUP/PGS OCR

Subtitle Edit does not show the SUP import or OCR option

Check the current official release assets, requirements and help. Menu labels can vary by release and operating system. Do not install an unofficial repack just to find a different menu.

OCR keeps choosing the wrong letters

Confirm the OCR language, try an OCR method that supports the script and test representative captions. Stylized fonts, outlines and low contrast can all reduce recognition quality.

Unknown words appear repeatedly

Correct real names and recurring terms carefully. Use add-to-dictionary or replace-all only after confirming the same correction is valid in multiple examples.

Formatting or positioning is missing

This is a format limitation, not necessarily an OCR failure. SRT cannot reproduce all PGS image styling and positioning. Re-add meaningful italics when supported.

SRT characters appear as boxes or question marks

Save in UTF-8, confirm the player and selected font support the script, and reopen the saved file to verify the characters were written correctly.

Subtitle timing is wrong

Confirm the SUP and video come from the same edition or cut. Preview several points across the video. A constant offset can be corrected differently from progressive drift.

The saved file is not SRT

Choose SubRip as the output format before saving. Confirm the filename ends in .srt. Changing only the extension is not sufficient.

Related SUP and PGS Guides

Browse all SUP and PGS guides.

Frequently Asked Questions