File Formats

This page details the specifications for the files Capturly produces.

Output Files Overview

A desktop recording session produces two files: a high-quality WAV master for editing, and an MP4 that contains the video with synced audio for preview and simple edits.

Recording in the browser produces a single .mp4 (video + audio); the separate WAV master is a desktop feature. See Recording in your browser.

Audio Master (*_audio.wav)

Your primary audio file for podcast editing and production, written alongside the video on desktop.

Specifications

Capturly doesn’t force a channel count — the WAV carries however many channels your microphone or interface presents. Most USB podcast microphones are mono; most audio interfaces present stereo. Size estimates below assume mono; double them for stereo.

On Windows, the 96 kHz / 24-bit WAV master is produced by a dedicated audio process alongside the video; the browser produces no WAV at all.

Why WAV?

WAV (Waveform Audio File Format) is chosen because:

• Uncompressed: No quality loss from compression
• Universal: Works in all audio software
• Archival quality: Preserves original recording fidelity
• Industry standard: Professional workflows expect WAV

Sample Rate Explained

Higher sample rates capture more audio detail and provide more flexibility in post-production (pitch shifting, time stretching) without artifacts.

Bit Depth Explained

Higher bit depth means greater dynamic range, capturing both quiet and loud sounds with more precision.

File Size Estimates

Video (*_video.mp4)

A single MP4 with H.264 video and synced AAC audio. It plays anywhere, drops straight into any editor, and doubles as a self-contained backup — while the separate WAV master preserves full audio fidelity for detailed editing.

Specifications

The AAC audio in the MP4 is a compressed convenience track. For the highest audio quality, edit from the separate *_audio.wav master.

Hardware Acceleration

Video encoding uses hardware acceleration when available:

H.264 Codec Details

The AVC level is sized to the resolution and frame rate:

Bitrate ladder and file sizes

Target bitrates by resolution. Sizes assume 30 fps and vary with content complexity (motion, detail).

A camera that can’t sustain the target negotiates down rather than failing — constraints are requested as ideal, not exact.

File Naming Convention

All files follow this naming pattern:

[SessionID]_[DisplayName]_[Date]_[Time]_[Type].[ext]

Components

Example Filenames

A7B3C9_John_2026-01-21_143022_audio.wav
A7B3C9_John_2026-01-21_143022_video.mp4

Directory Structure

Recordings are organized by date:

[Save Location]/
└── [YYYY-MM-DD]/
    └── [SessionID]_[Name]_[Date]_[Time]_audio.wav
    └── [SessionID]_[Name]_[Date]_[Time]_video.mp4

Example

Documents/Podcasts/
├── 2026-01-20/
│   └── B2C4D6_John_2026-01-20_100015_audio.wav
│   └── B2C4D6_John_2026-01-20_100015_video.mp4
└── 2026-01-21/
    └── A7B3C9_John_2026-01-21_143022_audio.wav
    └── A7B3C9_John_2026-01-21_143022_video.mp4

Sync beep

The head of the audio carries a 1000 Hz tone lasting 0.5 seconds, mixed with your microphone input rather than replacing it. It’s the alignment reference for post-production.

Which files carry it:

See Sync Beep for how to use it.

Compatibility

Audio Files (.wav)

Compatible with virtually all audio software:

• Adobe Audition
• Audacity
• GarageBand
• Logic Pro
• Reaper
• Pro Tools
• Descript
• Any media player

Video Files (.mp4)

Compatible with:

• Adobe Premiere Pro
• Final Cut Pro
• DaVinci Resolve
• iMovie
• Descript
• VLC
• Any modern video player

Storage Recommendations

Minimum Free Space

Roughly double the expected output, so a long take never runs the disk down.

Pre-flight sizes its disk check to the resolution you’re about to record, so a 4K take is refused on a disk that would have accepted 1080p.

Backup Strategy

1. During recording: Save to reliable storage (SSD preferred)
2. After recording: Copy to backup location
3. Archive: Keep raw files until project is complete
4. Long-term: Archive final exports separately from raw files

Next Steps

• Review system requirements
• Learn keyboard shortcuts
• See post-production guide for editing