go-libraw

Go binding for LibRaw

Background

I needed a go binding for LibRaw to convert RAW image formats from Nikon and Canon cameras (.NEF, .CR2, ...) to JPEGs or PNGs. After doing some searching I only found some older wrappers that have been inactive for a while, so I decided to write my own.

Install

go get github.com/seppedelanghe/go-libraw@v0.2.0

Options

The LibRaw output params are passed to LibRaw using the ProcessorOptions struct. More information about LibRaw Output params can be found here The Go struct has some small differences with the LibRaw struct to prevent setting invalid values. For example, LibRaw's struct uses 0 and 1 to represent boolean values, in the Go struct I just used the bool type to avoid confusion. A custom struct Box is also introduced to avoid setting x, y, w, h values in the wrong order as in C, a [4]uint array would be used.

Building

MacOS:

brew install libraw
go build .

Ubuntu:

1. Install libraw -> apt install libraw-dev
2. Run go build .

Other:

1. Install libraw (often called libraw-dev)
2. (optional) Update the #cgo flags to point the correct directory for libraw
3. Run go build .

Tested on:

• MacOS 13
• Ubuntu 24.04 ARM
• Ubuntu 24.04 x64

Tests

Running tests can be done using go test -v .

Example usage

const pathToRawFile = "./dir/file.NEF"
processor := libraw.NewProcessor(libraw.NewProcessorOptions())
img, metadata, err := processor.ProcessRaw(pathToRawFile)
// handle err...

For a full example see: cmd/example.go

Credits

• Existing golibraw wrapper by enricod: https://github.com/enricod/golibraw