Lip sync is acceptable, but it weakens on longer sentences.
What was measured
Lip Sync Accuracy
Does the dubbed audio visually match lip movements in the original video?
decisive for this rankingtransformation
If the dubbed audio does not match the on-screen mouth movements, the core purpose of video translation with lip sync has failed. (3 of 3 judges)
What was given, what came back
Test input: Hindi vlog-style talking head (Hindi → English) · video · group: video-translation-voice-clone-lip-sync
Input — what we sent
HeyGen — Input 2 Educational.mp4
Input not captured
This run recorded no prompt or input file for the test, so we cannot show you what produced the result below. Capture gaps are tracked, not hidden.
A casual Hindi/Hinglish talking-head or vlog-style creator video translated into English to stress informal language handling, slang, and natural-sounding voice cloning on real creator content.
Output — unretouched
No output artifact
The verdict rests on the tester's written observation alone — no file was captured for this cell.
Also checked on this input — same tool, 6 other criteria
Translation Accuracy✓ WorkedProduces mostly accurate English→Spanish translation for structured educational narration.Translation Accuracy✓ WorkedProduces a semantically accurate English→Hindi translation that preserves the energetic fitness tone.Translation Accuracy◐ MixedProduces an understandable English translation, but it becomes literal and loses natural conversational flow.Voice Cloning Quality◐ MixedThe dubbed voice sounds slightly robotic rather than fully natural.Voice Cloning Quality⚠ StruggledThe dubbed voice does not fully match the speaker's casual conversational tone.Voice Cloning Quality✓ WorkedGenerates a dubbed voice whose tone matches the original speaker's energetic fitness style.
Provenance
- Observation
- 3f569910-d750-4754-8623-e5774a7e1ddb
- Evidence run
- 9feca581-b454-4bda-a610-a646cd0092f0
- Study
- Translate Videos with Voice Cloning and Lip Sync Using AI
- Research task
- 86b96dfpf
- Tested at
- Jun 24, 2026
- Source
- first-party
- Evidence state
- verified
- Proof shown
- input only
- Cost / latency
- not captured
- Repeat run
- not captured
- Tester
- not captured
The last three rows are honest blanks, not placeholders — our capture has no field for them yet.
Query this
get_evidence({
tool: "heygen",
scenario: "video-translation-voice-clone-lip-sync"
})MCP · mcp.aidemos.com/api/mcp
Free with attribution.
Same input, same check — 5 other tools
measured on Lip Sync Accuracy
D-ID✗ FailedLip sync worked well on the AI avatar, but it did not apply to the original video.Dubverse✓ WorkedAchieves more precise lip sync than the other tested inputs.ElevenLabs✗ FailedProvides no built-in lip sync or video integration, so the dubbed audio cannot visually align with the original mouth movements inside the tool.Rask AI◐ MixedPerforms better on slower, clearer speech, but still shows slight lip-movement delays in some frames.Sync Labs◐ MixedLip sync worked overall, but it struggled during expressive facial movements and fast speech.
This evidence is published in
Real inputs and real outputs, no retouching · every cell queryable via API & MCP · aidemos.com