Matroska Video
VideoMatroska’s video container supports multiple audio/subtitle tracks and chapters, though a player may not implement every feature.
- What it is used for
- Video with multiple audio and subtitle tracks
- What the file contains
- Binary data
All sections, questions and sources
Content reviewed： · Editor：Kai
First: choose for your purpose
MKV can carry several audio/subtitle tracks and chapters. Check defaults/player support for wrong-language audio or missing subtitles. Choose retained tracks when moving to MP4; subtitle transfer is not automatic.
Opening steps
Choose your environment or purpose to see its steps.
Menu labels and support vary by app, OS and version. Preserve the original before making changes.
Troubleshooting by symptom
- A different default audio track may explain missing Japanese audio; inspect the track list.
- Subtitle styling depends on subtitle format, attached fonts and player support; inspect each track.
- Different language: inspect player defaults and the file’s track list.
- Overlapping subtitles: inspect internal/external simultaneous tracks and any burnt-in captions.
- Missing chapters/subtitles after MP4 conversion: inspect output selection/format support and whether only video was transferred.
MKV → MP4
- Inspect streams in a compatible tool and choose which to keep.
- Remux compatible streams or convert unsupported ones, then verify the output.
- Verify required audio, subtitles, chapters, language, sync and full duration.
Subtitles, chapters, attachments and audio tracks may be lost; check settings that select only the first audio stream.
Select audio and subtitles
Inspect language, commentary and channels across audio tracks. Text, image and styled subtitle formats have different support.
For changed subtitle fonts, inspect attachments/player support; burnt-in captions remain even without subtitle tracks.
Source for these steps：Matroska · Specification Notes / Matroska · Codec Mappings
Checking transfer to MP4
Distinguish remux-compatible streams from those needing re-encoding and explicitly choose retained tracks in tools such as FFmpeg.
External subtitles, format conversion and burning in produce different results; burnt-in captions cannot be disabled as a track.
Source for these steps：FFmpeg · ffmpeg Documentation
Related-format differences
| Format / choice | Purpose and preserved information |
|---|---|
| MKV | Container for multiple tracks/chapters. |
| MP4 | Compatibility-oriented delivery without universal subtitle transfer. |
| SRT / ASS | Subtitle formats requiring style/placement/external-resource checks. |
Handling and security
Avoid running attached files and use an updated player from a trusted source.
Questions and answers
Can MKV contain multiple audio tracks?
Yes. Select through the player’s audio menu.
Can all subtitles move to MP4?
It depends on subtitle format/tool; conversion or burn-in may be needed.
Are MKV and WebM identical?
WebM is a constrained Matroska-based format; arbitrary MKV is not WebM.
Why do captions remain with subtitles disabled?
They may be burnt into the picture rather than selectable tracks.
Does MP4 conversion retain all audio?
It depends on selected tracks/codecs; verify them all.
Format facts: name, steward and MIME type
- Formal name
- Matroska Video
- Steward / specification
- Matroska Project / IETF CELLAR
- MIME type
- video/matroska (also video/x-matroska)
Primary and official sources
- Project documentationSpecification Notes
Explains that players need not implement every container feature.
Matroska · Link checked： - Project documentationCodec Mappings
Defines codec identifiers carried in Matroska.
Matroska · Link checked： - Project documentationffmpeg Documentation
Documents transcoding versus stream copying.
FFmpeg · Link checked： - Project documentationVLC User Documentation
Player documentation for desktop, Android and iOS.
VideoLAN · Link checked：