JXL to CR2 Converter

Encoding: the JXL uses lossy VarDCT or lossless modular coding; existing JPEGs can be repacked without loss; CR2 uses lossless JPEG-compressed sensor data, cut into vertical slices, and the download is a Linear DNG: demosaiced 8-bit RGB with the colour matrices raw editors need.

Bit depth: 8 to 16 bits per channel, or floating point in the JXL; CR2 allows 12 or 14 bits per channel, and the DNG written here has 8 bits per channel, linearised. 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; CR2 supports camera RGB from a Bayer mosaic, with the Picture Style recorded in the maker notes, written here as 8-bit sRGB.

Transparency: the JXL stores it as an extra channel in the codestream; the DNG has none, so transparent areas are filled with the colour you choose.

Animation: frames inside a single codestream; the DNG 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; CR2 can carry EXIF, Canon maker notes (Picture Style, lens, focus points) and the embedded previews, 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.

CR2 is the raw format of Canon EOS cameras from 2004 until CR3 replaced it in 2018. It holds the sensor's 12 or 14-bit readings, losslessly compressed, plus a large JPEG preview rendered with the camera's Picture Style.

CR2 is TIFF-based: the TIFF header is followed by the letters 'CR' and version 2.0, then four image directories: a large JPEG preview with the EXIF block, a 160×120 thumbnail, a small uncompressed RGB image, and the sensor data as lossless JPEG cut into vertical slices.

CR2 files come from Canon EOS DSLRs made from 2004 to 2018, such as the 5D Mark II and III, 6D, 7D and the Rebel series.

Forms and workflows that ask for CR2 usually feed a raw editor, and each of those opens DNG as well, so the DNG can take the CR2's place. Keep the JXL if you only need to view or share the picture.

What CR2 offers when it comes straight from the camera: Large embedded JPEG rendered with the camera's Picture Style; Lossless 12 or 14-bit sensor data; Widely supported after fourteen years of Canon DSLRs. Its drawbacks: Replaced by CR3 in 2018, so current Canon bodies no longer write it; 20 to 50 MB per photo; Sliced lossless JPEG data that only raw decoders can read.