MEF to AVIF Converter

Change MEF to AVIF — browser-based tool

Drop files here. 1 GB maximum file size or Sign Up
to
Facebook Amazon Microsoft Tesla Nestle Walmart L'Oreal

Wide Format Support

Beyond AVIF, Convertio handles OUT_COUNT+ output formats for MEF — find the perfect target for any workflow.

Cloud-Based Engine

Conversion runs entirely on cloud servers — your computer stays fast and responsive even when processing large MEF files.

Effortless Workflow

Upload your MEF, select AVIF, and download the result. Three simple steps — no registration or technical knowledge needed.

How to convert MEF to AVIF

1

Select files from Computer, Google Drive, Dropbox, URL or by dragging it on the page.

2

Choose avif or any other format you need as a result (more than 200 formats supported)

3

Let the file convert and you can download your avif file right afterwards

About formats

MEF is the proprietary RAW image format used by Mamiya medium-format digital cameras, introduced with the Mamiya ZD in 2004 and continued through subsequent models including the DM series. MEF files capture the unprocessed output from Mamiya's large-area CCD sensors — typically 48x36mm or larger — at 16 bits per channel, preserving the full dynamic range and color depth of the medium-format sensor before any demosaicing, white balance, or tonal processing takes place. The format uses a TIFF-based container that stores the raw Bayer-pattern data alongside embedded JPEG previews and extensive EXIF metadata including Mamiya lens identification, shutter speed, aperture, and metering information. Mamiya (later reorganized as Mamiya Digital Imaging and eventually merged into Phase One's operations) has a legacy stretching back to 1940 in medium-format film photography, and the MEF format represents the digital continuation of that tradition. One advantage is the medium-format sensor's inherent imaging qualities: the larger sensor area captures more light per pixel, producing lower noise floors, smoother tonal gradations, and a shallower depth-of-field rendering that medium-format photographers value for portrait, fashion, and landscape work. RAW flexibility is another practical strength — MEF files processed in Adobe Lightroom, Capture One, or dcraw allow photographers to apply modern demosaicing and noise reduction algorithms to these sensors, often extracting noticeably better results than the camera's original processing offered.
Developer: Mamiya
Initial release: 2004
AVIF (AV1 Image File Format) is a modern image format derived from the AV1 video codec, developed by the Alliance for Open Media and specified in February 2019. The format leverages the intra-frame coding tools of AV1 — a royalty-free video codec backed by Google, Apple, Microsoft, Amazon, Netflix, and other major technology companies — to compress still images with substantially higher efficiency than JPEG, PNG, or even WebP. AVIF stores images in the HEIF (High Efficiency Image File Format) container, supporting both lossy and lossless compression, HDR (high dynamic range) with wide color gamuts up to 12-bit depth, alpha transparency, and animated sequences. At equivalent visual quality, AVIF files are typically 30-50% smaller than WebP and 50-70% smaller than JPEG, representing the largest compression improvement in mainstream image formats in over a decade. One advantage is exceptional compression efficiency — AVIF delivers visually indistinguishable images at dramatically lower file sizes, directly reducing bandwidth consumption and improving page load times for web content. The royalty-free licensing model provides another key strength: unlike HEIC/HEIF which relies on patent-encumbered HEVC, AVIF's AV1 foundation is free for anyone to implement without licensing fees. Browser support has reached broad adoption, with Chrome, Firefox, Safari, and Edge all rendering AVIF natively. The format is rapidly gaining adoption for web images where quality-to-size ratio is paramount.
Initial release: February 8, 2019

Frequently Asked Questions

Why convert MEF to AVIF?

Mamiya medium format RAW files are enormous and require specialized software — converting to AVIF makes them practical for everyday use.

What opens AVIF files?

AVIF files can be opened with Chrome, Firefox, Safari, Edge, GIMP, and modern image viewers on all platforms.

Do I need to pay for MEF to AVIF conversion?

Basic conversions are free for all users. Premium accounts provide extended limits and faster processing speeds.

How long does MEF to AVIF conversion take?

Most conversions finish in just a few seconds — server-side processing handles the heavy lifting, not your device.

Does MEF to AVIF work on Mac and Linux?

Convertio runs entirely in the browser — it works on Windows, macOS, Linux, and even mobile devices with no installs.

Are my MEF files safe during conversion?

Uploaded MEF files are deleted immediately after conversion. AVIF outputs are automatically removed within 24 hours.