API Reference

Complete API reference for the VIESUS Node.js native module — MyViesusObject constructor, Enhance method, error codes, and result JSON.

Linux Only

The VIESUS Node.js module is available on Linux only.

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Import

const viesus = require('viesus');

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new viesus.MyViesusObject(guid)

Creates and initializes a VIESUS enhancer instance. Create one object per worker thread and reuse it across multiple Enhance() calls — initialization is expensive.

Parameter	Type	Description
guid	string	Your VIESUS license GUID

const viesusObj = new viesus.MyViesusObject('4e8f35ab-7f72-4b1e-a1fd-2b5e9c58e9d3');

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viesusObj.Enhance(fromPath, toPath, iniPath, resPath)

Enhances a single image. Synchronous — must be called from a worker thread, not the main thread.

Parameter	Type	Description
fromPath	string	Absolute path to the input image
toPath	string	Absolute path for the enhanced output image
iniPath	string	Absolute path to the viesusini.json configuration file
resPath	string	Absolute path for the result JSON output file

Returns: number

• > 0 — success; value is processing time in milliseconds
• < 0 — error; see error codes

const result = viesusObj.Enhance(fromPath, toPath, iniPath, resPath);
if (result > 0) {
  console.log(`Enhanced in ${result}ms`);
} else {
  console.error(`Error: ${result}`);
}

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Error codes

Code	Description
-1	Init failed
-2	GUID wrong
-3	Internal error
-4	Loading image not possible
-5	Can't open file
-6	File not found
-7	File is empty
-8	Memory open internal error
-9	Enhancement failed — contact [e-mail]
-10	Parameter file not found
-11	Parameter file empty
-12	Output format not supported
-13	Error writing result file
-126	Enhancement failed — image was already enhanced
-378	Wrong GUID
< -18	Internal error — contact [e-mail]

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Result JSON

When WriteResultFiles: 1 is set in viesusini.json, a JSON file is written to resPath after each enhancement with per-image processing details:

{
  "brightCorrStrength": 0.011,
  "colorCorrStrength": 0.083,
  "contrCorrStrength": 0.0,
  "fdApplied": 1,
  "ggaApplied": 0,
  "globShpApplied": 0,
  "glowStrength": 0.0,
  "ieApplied": 1,
  "isArtificial": 0,
  "isMonochrome": 0,
  "locShpApplied": 1,
  "noiseStrength": 0.0,
  "nrApplied": 0,
  "rerApplied": 1,
  "rszApplied": 1,
  "rszSRApplied": 0,
  "arApplied": 0,
  "bgApplied": 0,
  "staApplied": 0
}

Field	Type	Description
brightCorrStrength	float	Applied brightness correction strength
colorCorrStrength	float	Applied color correction strength
fdApplied	int	1 if face detection ran
ieApplied	int	1 if image enhancement ran
isArtificial	int	1 if image was classified as artificial/synthetic
isMonochrome	int	1 if image was detected as monochrome
locShpApplied	int	1 if local sharpening was applied
rszApplied	int	1 if resizing was applied
rszSRApplied	int	1 if AI upscaling was used for resize
arApplied	int	1 if artifact removal was applied
bgApplied	int	1 if background handling was applied

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Thread pool pattern

The recommended production pattern uses node-worker-threads-pool:

// worker.js
const { parentPort, workerData } = require('worker_threads');
const viesus = require('viesus');

const viesusObj = new viesus.MyViesusObject(workerData);

parentPort.on('message', (job) => {
  const result = viesusObj.Enhance(job.fromPath, job.toPath, job.iniPath, job.resPath);
  parentPort.postMessage(result);
});

// main.js
const { StaticPool } = require('node-worker-threads-pool');

const pool = new StaticPool({
  size: Number(process.env.UV_THREADPOOL_SIZE),
  task: './worker.js',
  workerData: 'YOUR-GUID-HERE'
});

async function enhanceImage(fromPath, toPath, iniPath, resPath) {
  const result = await pool.exec({ fromPath, toPath, iniPath, resPath });
  if (result < 0) throw new Error(`VIESUS error: ${result}`);
  return result;
}

See Getting Started for the complete example.