HEIF to AV1 Converter

HEIF to AV1 Converter

A HEIF file is a single still image — one HEVC-encoded picture in an ISO container, the format iPhones save photos in — while AV1 is a video codec. So this conversion does not shrink your photo; it renders the still, holds it on screen for a duration you choose, and encodes that as a short, silent AV1 clip inside a Matroska container. Before you run it, it is worth knowing that almost everyone searching "HEIF to AV1" actually wants AVIF — the AV1-based image format — not an AV1 video. This page explains the difference, lists the specs of both formats, and walks through the conversion for the narrow case where you genuinely need a video file.

Did You Want a Video or a Still Image?

Every major converter that advertises "HEIF to AV1" (Convertio, CloudConvert, ezgif) actually outputs AVIF, a still image. Only pick AV1 video if you truly need a clip. Here is how the three realistic targets compare:

If you wanted a picture — to view, post, store, or attach — pick AVIF or JPG. AV1 video only makes sense for a video timeline.

HEIF Format at a Glance

AV1 Format at a Glance

How to Convert HEIF to AV1

1. Upload Your HEIF File: Drag and drop your .heif file onto the page or click "Add Files". Add several at once if you want either one clip per photo or a single combined clip.
2. Set the Duration: Open Advanced Options and use the Duration control to choose how long the still is held — the default is 5 seconds per frame, adjustable from a single frame up to 10 seconds.
3. Pick Background Color and Quality Preset (Optional): Background Color (default White) fills the letterbox bars when the photo's aspect ratio does not match the frame — any HEIF transparency is flattened onto it — and the Quality Preset (default "Very High (Recommended)") sets how finely AV1 encodes the picture.
4. Convert and Download: Click "Convert". Files are uploaded over an encrypted connection, processed on our servers, and deleted automatically after a few hours — no sign-up, no watermark. The output carries a .av1 extension; rename it to .mkv for players that expect a standard container.

Frequently Asked Questions

Did I actually want AVIF instead of AV1 video?

Very likely. AVIF (AV1 Image File Format) is a still image built on the AV1 codec — essentially one AV1 frame stored inside a HEIF container, per the AOMedia AVIF specification. It keeps alpha transparency and HDR and lands roughly 50-70% smaller than JPEG. AV1 by itself is a video codec, so HEIF to AV1 produces a short silent clip, not a picture. If you wanted a smaller, sharper version of the photo, use HEIF to AVIF instead.

Why does my HEIF to AV1 file play as a silent video?

Because a photo has no runtime and no sound. HEIF to AV1 is a still-image-to-video conversion: it renders one picture as video frames, with no audio source to draw from, so the output is silent by design. The clip's length is whatever you set in the Duration control. If you need audio, open the result in a video editor such as Shotcut or DaVinci Resolve and add a music or voiceover track there.

What is HEIF, and why is it hard to open outside Apple devices?

HEIF (High Efficiency Image File Format, ISO/IEC 23008-12, published 2015) is a still-image container built on the ISO Base Media File Format. On Apple hardware it usually holds an HEVC-encoded picture at roughly half the size of an equivalent JPEG. The catch is native support: Safari on macOS and iOS displays HEIF, but Chrome, Firefox and Edge do not render it without a plug-in — which is a common reason people convert HEIF out to a more portable format in the first place.

Why does the download have a .av1 extension, and what do I do with it?

AV1 is a codec, not a file container, so the encoded stream is wrapped in a Matroska container for playback. The file arrives with a .av1 extension, which some players do not recognize. Simply rename the file from .av1 to .mkv — the bytes are unchanged — and standard players such as VLC will open it. Browsers that support AV1 will also play it directly.

Which devices and browsers can play an AV1 file?

AV1 decoding is available in Chrome 70+, Firefox 67+ and Edge 121+, while Safari added it in version 17 and leans on hardware decoding, so playback on older Apple chips can be limited. Older phones and TVs without an AV1 decoder fall back to slower software playback or cannot play it at all. If broad compatibility matters more than file size, HEIF to MP4 uses H.264 and plays almost everywhere.

Does the AV1 clip keep my HEIF photo's transparency or HDR?

Transparency is not preserved — AV1 video in this pipeline has no alpha channel, so any transparent regions in the HEIF are flattened onto the Background Color you choose. HDR and wide-gamut color are treated more gently, but if your player or output path handles only 8-bit, a 10-bit HEIF is mapped down during encoding. If keeping alpha matters, use HEIF to AVIF, whose image format does carry transparency.

Can I turn several HEIF photos into one AV1 clip?

Yes. Upload multiple HEIF files and set the Merge strategy control: "Merge images" strings every photo into one AV1 clip, each held for the duration you set — ten photos at 5 seconds each yields a roughly 50-second slideshow — while "Video per image" outputs a separate clip for each file. Photos play in upload-list order.

Will the AV1 clip look as sharp as the original HEIF?

Close, at sensible settings. Because a held still has no motion between frames, AV1 compresses it very efficiently: the first frame carries the detail and the rest cost almost nothing. In our testing, a 12-megapixel photo held for 5 seconds on the "Very High" preset produced an AV1 clip well under 1 MB with no visible softening. Keep the resolution at the photo's native size rather than upscaling — stretching a smaller image past its real detail is what causes softness, not the codec.