imageTested formats & limitations
Last reviewed: . This page describes the test scope for this release, not a guarantee that every file with the same extension will decode.
What we check
| Case | Checks |
|---|---|
| PNG, WebP, AVIF | Mixed batch, transparent regions, JPEG output and file sizes |
| BMP and SVG | Raster output; SVG uses sanitized self-contained shapes |
| GIF | First-frame output and a two-frame sample exported to numbered JPGs |
| TIFF | A two-page LZW sample, with each page exported at its own dimensions |
| HEIC and EXIF | Public libheif HEIC sample decoded to 1280 × 854; all eight JPEG EXIF orientations compared against correctly transformed reference images |
| Downloads | Output dimensions, white background pixels, ZIP contents, duplicate file names and failure isolation for a corrupt PNG |
Device coverage
Development checks use a desktop Chromium browser and narrow viewport layouts. A narrow viewport is not a real iPhone or Android device. Safari, Firefox, real mobile memory limits and unusual camera formats still need wider device testing. Use a current browser with OffscreenCanvas and Web Worker support.
What is not preserved
JPG has no transparency or animation. Camera EXIF, GPS, original ICC profiles and HDR metadata are not copied. HEIC produces one still image. GIF timing is not stored in exported frames. TIFF variants and color profiles may render differently. SVG external resources are removed.
Batch limits
Up to 30 files, 50 MB each and 300 MB total input. Images and output dimensions are limited to 40 megapixels, and output sides to 16,384 pixels. A batch stops accumulating outputs at 256 MB. GIF export allows up to 200 frames and TIFF up to 100 pages per file. Browser memory can impose a lower practical limit.
How to report a problem
Contact the maintainer with the format, device, browser and visible error message. Do not send private images. Keep originals until you have inspected the results.