Video Subtitle and Text Removal

Use this workflow to remove hardcoded subtitles, watermarks, logos, lower thirds, plot hints, registration numbers, captions, or other visible text from video.

Want to inspect output quality before building? Try the same removal workflow in the Weydub web app: Remove subtitles online.

For the technical background behind OCR-guided detection, temporal grouping, false-positive controls, and video inpainting, read How Weydub removes hardcoded subtitles.

Endpoint

POST /v-w-c/gateway/ve/work/free

The task is asynchronous. Save body.idProject and body.dataList[].id, then use Async task model for polling, callbacks, retry behavior, and callback signing.

Access And Limits

Entitlement And Version Matrix

Removal has several versions with different cost, quality, and account requirements. Confirm the enabled tier before sending production traffic.

Removal Versions

Minimal Basic Payload

{
  "urls": ["https://example.com/video.mp4"],
  "needChineseOcclude": 1,
  "videoInpaintLang": "all",
  "callback": "https://your-domain.example/webhooks/weydub"
}

Use videoInpaintLang: "all" when source text language is uncertain. Use a specific language such as en, zh, es, or pt only when you know the visible text language.

Advanced Lite Payload

{
  "urls": ["https://example.com/video.mp4"],
  "needChineseOcclude": 2,
  "videoInpaintLang": "all",
  "videoInpaintMasks": "[{\"type\":\"remove\",\"region\":[[0,0.8],[1,0.8],[1,1],[0,1]]}]",
  "extraOptions": "{\"extra_inpaint_config\":{\"model\":\"advanced_lite\"}}"
}

Advanced Pro Bounding-Box Payload

{
  "urls": ["https://example.com/video.mp4"],
  "needChineseOcclude": 2,
  "videoInpaintLang": "all",
  "videoInpaintMasks": "[{\"type\":\"remove\",\"start\":0,\"end\":18,\"region\":[[0,0.8],[1,0.8],[1,1],[0,1]]}]",
  "extraOptions": "{\"extra_inpaint_config\":{\"model\":\"advanced_large_box\"}}"
}

Use bounding-box Pro when the text stays in a known area. Keep start and end tight for short-lived overlays such as plot hints or registration numbers.

Advanced Pro Full-Screen Payload

{
  "urls": ["https://example.com/video.mp4"],
  "needChineseOcclude": 1,
  "videoInpaintLang": "all",
  "extraOptions": "{\"extra_inpaint_config\":{\"model\":\"advanced_full\"}}"
}

Region Mask Payload

{
  "urls": ["https://example.com/video.mp4"],
  "needChineseOcclude": 2,
  "videoInpaintLang": "all",
  "videoInpaintMasks": "[{\"type\":\"remove_only_ocr\",\"start\":0,\"end\":12,\"region\":[[0,0.72],[1,0.72],[1,0.92],[0,0.92]]}]"
}

Coordinates are normalized from 0 to 1, ordered as top-left, top-right, bottom-right, bottom-left. This makes the same mask adapt across resolutions.

videoInpaintMasks Schema

videoInpaintMasks is a compact JSON string before signing. Some internal product flows hold it as an array before serialization, but public API clients should send the string form shown above unless your account contract says otherwise.

Use explicit end values when an overlay only appears during the first seconds. This prevents the model from erasing unrelated content later in the video.

Common Mask Coordinates

Quality And CRF

Weydub defaults to CRF 17, which is visually lossless for most distribution workflows. If your account enables encoder overrides, use extraOptions.write_options to request CRF 15 or 16 for extreme quality requirements. Lower CRF values can create much larger files and may add bandwidth or storage charges.

Example:

{
  "extraOptions": "{\"write_options\":{\"crf\":16},\"extra_inpaint_config\":{\"model\":\"advanced_full\"}}"
}

Parameters

Outputs

Successful tasks can return:

• videoUrl
• coverUrl
• sourceVideoUrl
• processStatus
• processProgress
• paidPoint
• task metadata under the returned work item

Poll until processStatus === 1 before reading output URLs.

Agent Notes

• Use Demo scenarios before customer media.
• Prefer region masks when subtitles always appear in a known band.
• Use videoInpaintLang: "all" when the source language is uncertain.
• Keep extraOptions and videoInpaintMasks compact and stringified before signing.
• Do not combine text removal with unrelated dubbing or translation features unless your payload exactly matches a documented combined workflow.