ARW to MKV Converter

ARW to MKV — Matroska or MP4 for a Still-Image Clip?

Converting a Sony Alpha raw to MKV produces a short, silent video that holds one rendered frame on screen for a duration you set. The question worth answering before you click anything is whether Matroska is the right wrapper for that, because the alternative — MP4 — carries exactly the same H.264 frame and plays in far more places. Short answer: pick MKV when the project, player, or editing pipeline is already standardised on Matroska, or when you want a codec MP4 cannot legally or practically carry. Pick ARW to MP4 for anything that has to play on a phone, a TV, or the web.

MKV vs MP4 for This Conversion

When to Pick MKV

• Your editor, player, or automated pipeline already ingests .mkv and you need a still slate, hold frame, or title card in the same container as everything else.
• You want a codec the MP4 page does not offer — Theora, VP8, MJPEG, HuffYUV, or one of the legacy MPEG-4 variants — inside a container that is happy to carry any of them.
• You are archiving to a container with an open, published specification rather than a licensing-encumbered one.

When to Pick MP4 Instead

• The clip has to play on a phone, a smart TV, a console, or a web page.
• You are sending it to someone whose software you cannot predict; MP4 is the file nobody has to think about.
• You want the smallest friction path from photo to shareable clip, in which case ARW to MP4 does the same render into a container everything opens.

How to Convert ARW to MKV

1. Upload Your ARW File: Drag and drop your Sony .arw onto the page or click "+ Add Files" to browse — straight off an α7, α6000-series, or older DSLR-A body, and several frames can be queued at once.
2. Set Merge Strategy and Image Duration: "Merge strategy" chooses "Merge images" (all uploads become one MKV) or "Video per image" (one file each). "Image Duration" runs from a single frame at 60fps up to 10 seconds per frame, with 5 seconds per frame pre-selected.
3. Check Video Codec, Quality Preset, and Background Color: "Video Codec" is pre-set to H.264 and lists twenty others; "Quality Preset" sits at Very High (Recommended); "Background Color" (White by default) fills any letterbox left when the photo's shape does not match the video frame.
4. Convert and Download: Click Convert and download the .mkv. Files upload over an encrypted connection, are processed on our servers, and are deleted automatically after a few hours. No sign-up, no watermark.

What Goes In and What Comes Out

Frequently Asked Questions

Does the MKV clip have any motion or sound?

No to both. From a single ARW the converter renders the photograph and holds that one frame for the duration you set — no pan, no zoom, no animation. It is also silent: a still image carries no audio, so there is nothing to encode, and the Audio Codec menu is hidden entirely for image sources. Uploading several photos with "Merge images" selected plays them back to back, each held for its duration, which is a sequence of stills rather than a cross-faded slideshow.

Which video codec does the MKV use, and what else can I choose?

H.264 is pre-selected. Matroska is codec-agnostic — it is an envelope, not a codec — so the dropdown on this page is unusually long: AV1, DivX, Flash Video, FLV, H.261, H.263, H.263+, H.264, H.265, HuffYUV, MJPEG, MPEG-1, MPEG-2, MPEG-4, MS MPEG-4, Theora, VP8, VP9, WMV 1, WMV 2, and Xvid. That breadth is the main practical reason to choose MKV over MP4 here, since the MP4 page offers eight of those. If you do not have a specific reason to change it, H.264 gives the widest player compatibility inside the container.

Is MKV actually better than MP4 for a one-frame clip?

Only situationally. The video frame inside is identical when both use H.264, so quality is not the deciding factor — compatibility is, and MP4 wins that comfortably. MKV earns its place when your pipeline is already Matroska, when you want a codec MP4 does not offer, or when you value an openly published container specification. For a clip that simply needs to play somewhere, ARW to MP4 is the better default.

Will an MKV play on my TV, phone, or in a web page?

Often not. Browsers do not play Matroska, and many phones, smart TVs, and set-top players reject the container even when they can decode the H.264 inside it. On the desktop it is a different story: VLC, mpv, and recent Windows builds handle MKV natively. If the file is going anywhere you cannot control, convert to MP4 rather than hoping — the video stream is the same, so nothing is gained by insisting on Matroska.

Do I lose the raw editing latitude when I convert ARW to MKV?

Yes. An ARW holds unprocessed sensor data — typically 12-bit on early Alpha bodies and 14-bit on most modern α models — which is why highlights, shadows, and white balance stay adjustable long after the shot. To become a video frame, that data must be demosaiced and tone-mapped, and the render bakes in white balance, exposure, and colour. Inside the MKV it behaves like any finished 8-bit picture. Keep the .arw as your master and treat the clip as an output.

How long is the clip, and can I chain several photos into one?

Image Duration sets it, from a single frame at 60fps to 10 seconds per frame, with 5 seconds per frame pre-selected — so one photo at the default gives a five-second clip. Selecting "Merge images" under Merge strategy joins every uploaded ARW into one MKV, each shown for that duration in upload order, so ten photos at five seconds each make a fifty-second sequence. "Video per image" produces separate files instead.

Why is there a white bar around my photo in the video?

Because your photo's aspect ratio does not match the video frame it is being placed into, so the difference is padded. That padding uses the Background Color control, which is White by default and can be set to any colour in the list — useful when the clip will sit against a dark background in an edit. Leaving Video resolution on "Keep original", or choosing a resolution closer to your camera's 3:2 shape, shrinks or removes the bars.

What happens to my ARW file after the conversion?

It is uploaded over an encrypted connection, rendered and muxed into MKV on our servers, and deleted automatically a few hours later — no sign-up, no watermark, never shared or made public. Only the file you download persists. A static H.264 frame compresses very efficiently, so the MKV is generally small; the slow part of the job is sending the raw, which is why smaller batches feel faster than one long queue.