JXL to DDS Converter

Encoding: the JXL uses lossy VarDCT or lossless modular coding; existing JPEGs can be repacked without loss; DDS uses block compression (BC1 to BC7, also called DXT) or uncompressed RGBA, and the download is an uncompressed 32-bit RGBA DDS texture with a single mip level, or DXT1 or DXT5 block compression if you choose it.

Bit depth: 8 to 16 bits per channel, or floating point in the JXL; DDS allows 8 bits per channel for common texture formats, and the DDS written here has 8 bits per channel. High-bit-depth JPEG XL files are reduced to 8 bits per channel.

Colour: sRGB, Display P3, linear and other spaces described in the codestream in the JXL; DDS supports RGB(A); normal maps and packed masks store data rather than colour, written here as 8-bit sRGB.

Transparency: the JXL stores it as an extra channel in the codestream; the DDS keeps it as alpha inside the compressed blocks (BC2, BC3, BC7) or a 1-bit cut-out (BC1).

Animation: frames inside a single codestream; the DDS holds one image, so only the first frame is converted.

Metadata: the JXL can carry EXIF and XMP boxes in the container form, often stripped by encoders; DDS can carry a 128-byte header (plus a DX10 header) describing the pixel format, nothing about the picture, but nothing is copied across.

JPEG XL is a next-generation format designed to replace JPEG. It compresses better than JPEG and WebP, supports lossless, HDR and progressive decoding, and can losslessly repack existing JPEGs.

A JPEG XL file is either a bare codestream starting with FF 0A or an ISO base media container whose 'jxlc' box holds the codestream. A recompressed JPEG keeps a 'jbrd' box that lets the original JPEG bytes be rebuilt exactly.

JXL files usually come from image editors, archival pipelines and lossless JPEG recompression.

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 is the better choice for game textures and mods, while JXL suits archiving and future-proof high quality storage.

DDS strengths: Loads straight into GPU memory; Mipmaps included. Drawbacks to weigh: Not viewable outside game tools; Lossy block compression.