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DDS to QOI Converter

Convert DDS to QOI in your browser. DDS files usually come from DirectX games, game mods and texture tools such as NVIDIA Texture Tools and Intel's texture plugin; QOI is the better fit for fast lossless storage in games and tools. You get a lossless RGBA QOI file. Nothing is uploaded.

  • Processed locally
  • No upload, no wait
  • No sign-up
  • No watermark

Drop images here

or choose files · paste with Ctrl/⌘ V

DDS expected · other image formats also work

Files are processed on this device. Nothing is uploaded.0 B uploaded

How to use DDS to QOI

  1. 1

    Add your DDS files: drop them here, choose them, or paste from the clipboard.

  2. 2

    There is nothing to tune: the QOI is written losslessly. Resizing and rotating are under More options if you need them.

  3. 3

    Click Convert. Each file is decoded and encoded in a background thread on this device.

  4. 4

    Download the .qoi files one at a time or together as a ZIP.

Why use Aback Images for dds to qoi

Where the QOI goes next

QOI opens in game engines, GIMP 3, ImageMagick, XnView MP and many small libraries.

QOI next to DDS

Both sides are lossless, so the size depends on how well the QOI encoder handles this picture compared with the DDS's block compression (BC1 to BC7, also called DXT) or uncompressed RGBA.

Written without a lossy pass

The QOI is written losslessly, so the pixels decoded from the DDS arrive unchanged.

Processed on your device

Your images are decoded, edited and encoded inside this browser tab by Web Workers. Nothing is uploaded to a server.

DDS vs QOI

What changes from DDS to QOI

Encoding: the DDS uses block compression (BC1 to BC7, also called DXT) or uncompressed RGBA; QOI uses lossless, byte-aligned run, index, difference and literal codes, and the download is a lossless RGBA QOI file.

Bit depth: 8 bits per channel for common texture formats in the DDS; QOI allows 8 bits per channel, and the QOI written here has 8 bits per channel.

Colour: RGB(A); normal maps and packed masks store data rather than colour in the DDS; QOI supports RGB or RGBA, tagged sRGB or linear, written here as 8-bit sRGB.

Transparency: the DDS stores it as alpha inside the compressed blocks (BC2, BC3, BC7) or a 1-bit cut-out (BC1); the QOI keeps it as a full 8-bit alpha channel.

Other images: the DDS can hold mipmaps, cubemap faces or texture arrays; only the main image is converted.

Metadata: the DDS can carry a 128-byte header (plus a DX10 header) describing the pixel format, nothing about the picture; QOI can carry none: a 14-byte header holds only size, channels and colour space, but nothing is copied across.

About DDS

DDS is a GPU texture format used by DirectX games. It stores block-compressed textures (DXT/BC) and mipmaps that graphics cards decode directly.

A DDS file starts with 'DDS ' and a 124-byte header giving the size, mipmap count and pixel format: a FourCC such as DXT1 or DXT5, or 'DX10' followed by an extra header naming a DXGI format. The largest mipmap comes first.

DDS files usually come from DirectX games, game mods and texture tools such as NVIDIA Texture Tools and Intel's texture plugin.

About QOI

QOI is a modern lossless format that encodes 20-50 times faster than PNG with similar file sizes. It is popular in games and tools that value speed and simplicity.

A QOI file is a 14-byte header ('qoif', width, height, channels, colour space), a stream of chunks that each encode a run, an index into 64 recently seen colours, a small difference from the previous pixel or a literal value, and an 8-byte end marker.

When converting DDS to QOI makes sense

QOI is the better choice for fast lossless storage in games and tools, while DDS suits game textures and mods.

QOI strengths: Extremely fast lossless encode and decode; Simple, open spec. Drawbacks to weigh: Not supported by browsers or mainstream apps.

Limitations

  • Only the top-level image (the largest mipmap of the first surface) is converted; smaller mipmaps and other cubemap faces are left out.
  • Normal maps and packed masks hold data rather than colours, so they look purple or odd as ordinary pictures.
  • Browsers and most mainstream apps cannot open QOI; it is meant for games and tools that read it directly.
  • QOI files are usually close to PNG in size but much faster to encode and decode.

Frequently asked questions

Does converting DDS to QOI lose quality?

QOI is written losslessly, so the pixels are stored exactly as decoded. Not carried over: any mipmaps.

Is transparency kept in the QOI?

Yes. DDS stores it as alpha inside the compressed blocks (BC2, BC3, BC7) or a 1-bit cut-out (BC1), and the QOI is written with an alpha channel, so transparent areas stay transparent.

Which apps open QOI files?

Game engines, GIMP 3, ImageMagick, XnView MP and many small libraries. It does not open in web browsers.

Are my images uploaded anywhere?

No. Processing happens inside your browser with WebAssembly and Web Workers. The site only downloads the app code and codecs; your files never leave your device. You can confirm this with the live upload counter on the tool, or in your browser's network panel.

Can I process many files at once?

Yes. Drop a whole selection or folder. Files are processed in parallel on several worker threads, each result can be downloaded on its own, and everything can be saved as one ZIP.

Is it free? Is there a file limit or watermark?

It is free with no account, no watermark and no daily limit. The only limit is your device's memory: very large images (over roughly 100 megapixels) may be refused to keep the tab from crashing.