WebP to DNG Converter

Encoding: the WebP uses lossy VP8 coding or lossless VP8L; DNG uses lossless (or lossy) JPEG-compressed sensor data, plus optional JPEG previews, and the download is a Linear DNG: demosaiced 8-bit RGB with the colour matrices raw editors need.

Bit depth: 8 bits per channel in the WebP; DNG allows 8 to 16 bits per channel, and the DNG written here has 8 bits per channel, linearised.

Colour: RGB; lossy WebP stores colour at half resolution (4:2:0) in the WebP; DNG supports camera RGB plus the colour matrices that map it to XYZ (demosaiced linear RGB in a Linear DNG), written here as 8-bit sRGB.

Transparency: the WebP stores it as a separate alpha plane, available in lossy as well as lossless files; the DNG has none, so transparent areas are filled with the colour you choose.

Animation: ANMF frame chunks, each with its own delay and blending; the DNG holds one image, so only the first frame is converted.

Metadata: the WebP can carry EXIF, XMP and ICC chunks; DNG can carry EXIF, XMP and DNG tags for colour matrices, calibration and lens corrections, but nothing is copied across.

WebP is Google's web image format. It supports lossy and lossless compression, transparency and animation, and is typically 25 to 35 percent smaller than JPEG at the same visual quality.

A WebP is a RIFF file: 'RIFF', a length, 'WEBP', then chunks. A simple lossy file is one VP8 chunk and a lossless one is VP8L; the extended VP8X header announces alpha, animation, ICC, EXIF or XMP chunks.

WebP files usually come from websites, Chrome's Save image as, CDNs and Android apps.

DNG is Adobe's openly documented raw format. Some cameras and phones record it directly, Adobe DNG Converter turns other brands' raw files into it, and a Linear DNG holds already-demosaiced RGB that raw editors treat like any other raw file.

DNG is built on TIFF/EP. The raw image sits in a sub-IFD marked as the main image, with tags for black and white levels, colour matrices and the colour filter pattern; a Linear DNG (PhotometricInterpretation 34892) stores demosaiced RGB instead of a mosaic. Previews are optional, and Adobe DNG Converter can write a medium (1024 px), full-size or no preview.

DNG is the better choice for raw editing and archiving raw files in an open format, while WebP suits images on websites and in apps.

DNG strengths: Open specification read by every raw editor; Lossless compression and optional previews; Recorded directly by Leica, Pentax, DJI drones and phones. Drawbacks to weigh: Large files; No browser or ordinary photo viewer support on every platform.