Waveform Generator
Render an audio file as a static waveform image (PNG/SVG) for thumbnails, podcasts, and previews.
What is Waveform Generator?
A waveform image renderer for podcast cover art, video thumbnails, social previews and audio player placeholders.
How it works
The file is decoded locally and reduced to a peak envelope, then drawn to a canvas (or emitted as SVG markup) in the style, size and colour you choose. The preview is rendered at the exact export resolution.
- Load your file. Drag a file onto the drop zone or pick one from your device. It is read locally by the browser and never uploaded.
- Set the options. Adjust the handles, format, quality or threshold controls — the preview updates as you change them.
- Process and download. Run the tool, then download the result. Compare the reported before/after size for compressors and converters.
Examples
A 42 MB podcast episode → 9 MB MP3
Trim the intro, normalise to −16 LUFS, and export at 96 kbps mono — a typical interview lands around a fifth of the original size.
A phone video with the wrong orientation
Rotate 90° and the width/height swap in the output, so it plays upright in every player instead of relying on metadata flags.
Common mistakes
Expecting instant encoders
Video encoding runs in single-threaded WebAssembly, so a clip takes roughly its own length (or a little longer) to re-encode. Stream-copy operations are near-instant by comparison.
Re-encoding when a copy would do
Trimming, removing audio and joining same-codec clips can copy streams without re-encoding — pick the copy option when it is offered to avoid any quality loss.
Ignoring the first-load download
The media engine is about 31 MB and is fetched on first use, then cached. The first conversion on a connection is slower than every later one.
Frequently asked questions
Should I export PNG or SVG?
SVG scales to any size and stays razor sharp — ideal for websites and print. PNG is simpler for video overlays and social uploads, especially with a transparent background.
What size should a podcast cover waveform be?
1400×1400 for podcast artwork, 1280×720 for video thumbnails, and 1200×630 for Open Graph images.
Does a long recording produce a huge image?
No. The waveform is always reduced to a fixed number of peak buckets, so a three-hour recording renders at the same image size as a three-minute one.