NSFW Detection API Usage & Content Analysis

Authentication

All requests must be signed using your apiSecret . Send signature in header x-signature .

Required fields (must come BEFORE file):

• • projectId
• • apiKey
• • nonce (random alphanumeric exactly 10 characters)
• • timestamp

Signature Generation

Follow these steps to generate the request signature:

1. Send a POST request using multipart/form-data .
2. Include required fields: projectId , apiKey , nonce , timestamp .
3. Create a payload object using only these fields.
4. Sort the payload keys in ascending order before converting to string.
5. Generate HMAC-SHA256 hash using your apiSecret .
6. Send the generated hash in header x-signature .

import crypto from "node:crypto";

const payload = { nonce, projectId, apiKey, timestamp };

const stableStringify = (obj) =>
  JSON.stringify(Object.keys(obj).sort().reduce((a,k)=>{a[k]=obj[k];return a;},{}));

const signature = crypto
  .createHmac("sha256", apiSecret)
  .update(stableStringify(payload))
  .digest("hex");

const payload = { nonce, projectId, apiKey, timestamp };

const stableStringify = (obj) =>
  JSON.stringify(Object.keys(obj).sort().reduce((a,k)=>{a[k]=obj[k];return a;},{}));

const encoder = new TextEncoder();
const key = await crypto.subtle.importKey(
  "raw",
  encoder.encode(apiSecret),
  { name: "HMAC", hash: "SHA-256" },
  false,
  ["sign"]
);

const sigBuffer = await crypto.subtle.sign(
  "HMAC",
  key,
  encoder.encode(stableStringify(payload))
);

const signature = [...new Uint8Array(sigBuffer)]
  .map(b => b.toString(16).padStart(2, "0"))
  .join("");

import hmac, hashlib, json

payload = {
  "nonce": nonce,
  "projectId": projectId,
  "apiKey": apiKey,
  "timestamp": timestamp
}

stable = json.dumps(payload, sort_keys=True)

signature = hmac.new(
  apiSecret.encode(),
  stable.encode(),
  hashlib.sha256
).hexdigest()

⚠️ Always sort keys before hashing.

Reduce Image Size (Client Side)

Max allowed size is 200KB . Compress images before upload to avoid errors.

Resize + reduce quality for best results.

async function compressImage(file) {
  const img = await createImageBitmap(file);

  const canvas = document.createElement("canvas");
  const scale = Math.min(800 / img.width, 1);

  canvas.width = img.width * scale;
  canvas.height = img.height * scale;

  const ctx = canvas.getContext("2d");
  ctx.drawImage(img, 0, 0, canvas.width, canvas.height);

  return new Promise((resolve) => {
    canvas.toBlob(resolve, "image/jpeg", 0.7);
  });
}

import sharp from "sharp";

const buffer = await sharp("input.jpg")
  .resize({ width: 800 })
  .jpeg({ quality: 70 })
  .toBuffer();

from PIL import Image

img = Image.open("input.jpg")
img = img.resize((800, int(img.height * 800 / img.width)))

img.save("output.jpg", quality=70, optimize=True)

import 'package:flutter_image_compress/flutter_image_compress.dart';

final result = await FlutterImageCompress.compressWithFile(
  file.path,
  minWidth: 800,
  quality: 70,
);

⚡ Resize + quality 60–80 → best balance between size & accuracy

Single Image

Upload one image using multipart form-data. Field name must be image .

curl -X POST https://api.voyantnetworks.com/v1/nsfw/analyze \
  -H "x-signature: SIGNATURE" \
  -F "projectId=YOUR_PROJECT_ID" \
  -F "apiKey=YOUR_API_KEY" \
  -F "nonce=123456" \
  -F "timestamp=TIMESTAMP" \
  -F "image=@file.jpg"

Batch (Max 5 Images)

Upload multiple images using field name images . Max 5 files per request.

curl -X POST https://api.voyantnetworks.com/v1/nsfw/analyze/batch \
  -H "x-signature: SIGNATURE" \
  -F "projectId=YOUR_PROJECT_ID" \
  -F "apiKey=YOUR_API_KEY" \
  -F "nonce=123456" \
  -F "timestamp=TIMESTAMP" \
  -F "images=@1.jpg" \
  -F "images=@2.jpg"

Response Format

Returns whether the image is classified as NSFW.

{
  "success": true,
  "nsfw": false
}