Sonix transcribes your GSM file and exports it as WebVTT captions perfect for HTML5 video and web platforms.
Telephone-quality audio for voicemail and calls
GSM is a compressed audio stream that is primarily used by cell phones. GSM files are designed for telephone-quality audio use in Europe and stores audio mainly for telephone quality voice. It makes for a good balance between size of file and quality retention with data around 96KB per minute. GSM is primarily used for voicemail storage or to record phone conversations that will be played back later.
Telephone-grade audio; good for speech, not music
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Upload your GSM file from your computer or cloud storage.
Choose from 53+ languages spoken in your file.
Sonix AI transcribes and timestamps your GSM audio.
Fine-tune caption timing and text with our editor.
Download your GSM captions as a WebVTT file.
Yes! Sonix transcribes your GSM file with precise timestamps and exports it as WebVTT captions for web video.
WebVTT (Web Video Text Tracks) is the native caption format for HTML5 video. It's supported by all modern browsers and video platforms.
Use VTT for web video (HTML5) and SRT for video editors. VTT supports advanced styling like colors and positioning.
Yes! VTT supports CSS styling for colors, fonts, positioning, and more. Customize how your captions appear on screen.
VTT is supported by Chrome, Firefox, Safari, Edge, and all modern browsers. It's the web standard for video captions.
Absolutely! VTT works seamlessly with video.js, Plyr, JW Player, and other HTML5 video players.
VTT is the web standard for captions, supported by all modern browsers.
Apply CSS styling for colors, fonts, positioning, and more.
Word-level timestamps ensure perfect sync with your video.
Works with all HTML5 video players and web platforms.
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