LibRaw-Wasm

https://github.com/ybouane/libraw-wasm
Admin
LibRaw-Wasm is a WebAssembly build of LibRaw that enables decoding and processing of RAW image files...
Tokens:4,421
Snippets:11
Trust Score:8
Update:1 month ago
Show doc for...
Tokens:
Raw
### Install libraw-wasm via npm

Source: https://github.com/ybouane/libraw-wasm/blob/main/readme.md

Install the libraw-wasm package using npm. This is the required first step before using the library.

```bash
npm install libraw-wasm
```

--------------------------------

### Basic usage of LibRaw-Wasm API

Source: https://github.com/ybouane/libraw-wasm/blob/main/readme.md

Shows how to import LibRaw, open a RAW file, fetch metadata, get decoded image data, and retrieve raw sensor data. The imageData() call rejects on decoding failure, so wrap it in try/catch for untrusted files. The rawImageData() returns an object with raw_width, raw_height, width, height, top_margin, left_margin, and a Uint16Array data property.

```javascript
import LibRaw from 'libraw-wasm';

const output = document.getElementById('output');
// Instantiate LibRaw
const raw = new LibRaw();
// Open (decode) the RAW file
await raw.open(new Uint8Array(fileBuffer), { /* settings */ });

// Fetch metadata
const meta = await raw.metadata(/* fullOutput=false */);
console.log('Metadata:', meta);
output.innerText = JSON.stringify(meta, null, 4);

// Fetch the decoded image data (RGB pixels).
// imageData() rejects if decoding fails (e.g. a compression format this build
// can't decode), so wrap it in try/catch when handling untrusted files.
try {
	const imageData = await raw.imageData();
	console.log('Image data:', imageData);
	console.log('Image data length:', imageData.data.length);
} catch (err) {
	console.error('Failed to decode image:', err);
}

// Fetch the raw, undebayered sensor data (16-bit mosaic, no demosaicing)
const rawImageData = await raw.rawImageData();
console.log('Raw sensor data:', rawImageData); // { raw_width, raw_height, width, height, top_margin, left_margin, data: Uint16Array }
```

--------------------------------

### Load and decode RAW file with LibRaw WASM

Source: https://github.com/ybouane/libraw-wasm/blob/main/example.html

This snippet shows how to use the LibRaw WASM library to read a RAW file selected by the user, configure decoding options, and retrieve metadata and image data. It listens for file selection, reads the file as an ArrayBuffer, instantiates LibRaw, opens the file with various options, and logs the results.

```javascript
import LibRaw from './index.js';
const fileInput = document.getElementById('file');
const output = document.getElementById('output');

// Listen for file selection
fileInput.addEventListener('change', async (event) => {
  const file = event.target.files[0];
  if (!file) return;

  try {
    // Read the RAW file into an ArrayBuffer
    const arrayBuffer = await file.arrayBuffer();
    console.log(arrayBuffer);

    // Instantiate LibRaw
    const raw = new LibRaw();

    // Open (decode) the RAW file
    await raw.open(new Uint8Array(arrayBuffer), {
      bright: 1.0, // -b <float> : brightness
      threshold: 0.0, // -n <float> : wavelet denoise threshold
      autoBrightThr: 0.01, // portion of clipped pixels for auto-brightening
      adjustMaximumThr: 0.75, // auto-adjust max if channel overflow above threshold
      expShift: 1.0, // exposure shift in linear scale (requires expCorrec=1)
      expPreser: 0.0, // preserve highlights when expShift>1 (0..1)
      halfSize: false, // -h : output at 1/2 size
      fourColorRgb: false, // -f : separate interpolation for two green channels
      highlight: 0, // -H : highlight mode (0..9)
      useAutoWb: false, // -a : auto white balance
      useCameraWb: false, // -w : camera's recorded WB
      useCameraMatrix: 1, // +M/-M : color profile usage (0=off,1=on if WB,3=always)
      outputColor: 1, // -o : output colorspace (0..8) (0=raw,1=sRGB,2=Adobe, etc.)
      outputBps: 8, // -4 : 8 or 16 bits per sample
      outputTiff: false, // -T : output TIFF if true, else PPM
      outputFlags: 0, // bitfield for custom output flags
      userFlip: -1, // -t : flip/rotate (0..7, default=-1 means use RAW value)
      userQual: 3, // -q : interpolation quality (0..12)
      userBlack: -1, // -k : user black level
      userCblack: [-1, -1, -1, -1], // per-channel black offsets
      userSat: 0, // -S : saturation level
      medPasses: 0, // -m : median filter passes
      noAutoBright: false, // -W : don't apply auto brightness
      useFujiRotate: -1, // -j : -1=use, 0=off, 1=on, for Fuji sensor rotation
      greenMatching: false, // fix green channel imbalance (not a dcraw key)
      dcbIterations: -1, // additional DCB passes (-1=off)
      dcbEnhanceFl: false, // enhance color fidelity in DCB
      fbddNoiserd: 0, // 0=off,1=light,2=full FBDD denoise
      expCorrec: false, // enable exposure correction (then expShift, expPreser apply)
      noAutoScale: false, // skip scale_colors (affects WB)
      noInterpolation: false, // skip demosaic entirely (outputs raw mosaic)
      greybox: null, // -A x y w h : rectangle (x,y,width,height) for WB calc
      cropbox: null, // Cropping rectangle (left, top, w, h) applied before rotation
      aber: null, // -C (red multiplier = aber[0], blue multiplier = aber[2])
      gamm: null, // -g power toe_slope (1/power -> gamm[0], gamm[1] -> slope)
      userMul: null, // -r mul0 mul1 mul2 mul3 : user WB multipliers (r, g, b, g2)
      outputProfile: null, // -o <filename> : output ICC profile (if compiled w/ LCMS)
      cameraProfile: null, // -p <filename> or 'embed' : camera ICC profile
      badPixels: null, // -P <file> : file with bad pixels map
      darkFrame: null, // -K <file> : file with dark frame (16-bit PGM)
    });

    // Fetch metadata
    const meta = await raw.metadata(true);
    console.log('Metadata:', meta);
    output.innerText = JSON.stringify(meta, null, 4);

    // Fetch the decoded image data (RGB pixels)
    const imageData = await raw.imageData();
    console.log('Image data:', imageData);

    // If you want to interpret the data as a PPM (for example),
    // you could do something like convert to a text-based PPM or
    // place it in a <canvas>. For now, we just log it.
  } catch (err) {
    console.error('Error processing RAW:', err);
  }
});
```

--------------------------------

### libraw-wasm settings object

Source: https://github.com/ybouane/libraw-wasm/blob/main/readme.md

JavaScript object with all configurable processing options for libraw-wasm. Each property maps to a dcraw flag (e.g., bright to -b, threshold to -n). Defaults and valid ranges are shown in comments. Use this object to customize RAW decoding behavior.

```javascript
{
	bright: 1.0,			// -b <float> : brightness
	threshold: 0.0,			// -n <float> : wavelet denoise threshold
	autoBrightThr: 0.01,	// portion of clipped pixels for auto-brightening
	adjustMaximumThr: 0.75,	// auto-adjust max if channel overflow above threshold
	expShift: 1.0,			// exposure shift in linear scale (requires expCorrec=1)
	expPreser: 0.0,			// preserve highlights when expShift>1 (0..1)

	halfSize: false,		// -h  : output at 1/2 size
	fourColorRgb: false,	// -f  : separate interpolation for two green channels
	highlight: 0,			// -H  : highlight mode (0..9)
	useAutoWb: false,		// -a  : auto white balance
	useCameraWb: false,		// -w  : camera's recorded WB
	useCameraMatrix: 1,		// +M/-M : color profile usage (0=off,1=on if WB,3=always)
	outputColor: 1,			// -o  : output colorspace (0..8) (0=raw,1=sRGB,2=Adobe, etc.)
	outputBps: 8,			// -4  : 8 or 16 bits per sample
	outputTiff: false,		// -T  : output TIFF if true, else PPM
	outputFlags: 0,			// bitfield for custom output flags
	userFlip: -1,			// -t  : flip/rotate (0..7, default=-1 means use RAW value)
	userQual: 3,			// -q  : interpolation quality (0..12)
	userBlack: -1,			// -k  : user black level
	userCblack: [-1, -1, -1, -1], // per-channel black offsets
	userSat: 0,				// -S  : saturation level
	medPasses: 0,			// -m  : median filter passes
	noAutoBright: false,	// -W  : don't apply auto brightness
	useFujiRotate: -1,		// -j  : -1=use, 0=off, 1=on, for Fuji sensor rotation
	greenMatching: false,	// fix green channel imbalance (not a dcraw key)
	dcbIterations: -1,		// additional DCB passes (-1=off)
	dcbEnhanceFl: false,	// enhance color fidelity in DCB
	fbddNoiserd: 0,			// 0=off,1=light,2=full FBDD denoise
	expCorrec: false,		// enable exposure correction (then expShift, expPreser apply)
	noAutoScale: false,		// skip scale_colors (affects WB)
	noInterpolation: false,	// skip demosaic entirely (outputs raw mosaic)

	greybox: null,			// -A x y w h : rectangle (x,y,width,height) for WB calc
	cropbox: null,			// Cropping rectangle (left, top, w, h) applied before rotation
	aber: null,				// -C (red multiplier = aber[0], blue multiplier = aber[2])
	gamm: null,				// -g power toe_slope (1/power -> gamm[0], gamm[1] -> slope)
	userMul: null,			// -r mul0 mul1 mul2 mul3 : user WB multipliers (r, g, b, g2)

	outputProfile: null,	// -o <filename> : output ICC profile (if compiled w/ LCMS)
	cameraProfile: null,	// -p <filename> or 'embed' : camera ICC profile
	badPixels: null,		// -P <file> : file with bad pixels map
	darkFrame: null,		// -K <file> : file with dark frame (16-bit PGM)
}
```
Tokens:
Raw