Image Resizer
API Documentation

Overview

The Image Resizer API provides advanced image resizing with multiple resize modes including fit, fill, stretch, and crop. It supports custom dimensions, 40+ predefined size presets, and maintains high image quality with configurable compression settings and output formats. Perfect for responsive web design, thumbnail generation, and content optimization.

Base URL & Authentication

Base URL

https://api.chemhub.com/api/v1

Authentication

Include your API credentials in every request header.

X-API-Key: your_api_key
X-API-Secret: your_secret
Content-Type: application/json

Get API Keys

Follow these steps to obtain your API credentials:

Endpoints

Health Check

Health check endpoint to verify the Image Resizer service status and available backends.

Response

{
  "success": true,
  "status": "healthy",
  "img_resizer_backends": ["pil", "opencv"],
  "supported_formats": [".jpg", ".jpeg", ".png", ".webp", ".bmp", ".tiff"],
  "max_file_size_mb": 10,
  "standard_sizes": ["thumbnail", "small", "medium", "large", "hd", "full_hd", "4k", "avatar_xl"],
  "timestamp": "2026-07-23T12:00:00"
}

Code Examples

import requests

url = "https://api.chemhub.com/api/v1/img_resizer/health"

headers = {
    "X-API-Key": "your_api_key",
    "X-API-Secret": "your_secret"
}

res = requests.get(url, headers=headers)
print(res.json())

curl -X GET https://api.chemhub.com/api/v1/img_resizer/health \
-H "X-API-Key: your_api_key" \
-H "X-API-Secret: your_secret"

fetch('https://api.chemhub.com/api/v1/img_resizer/health', {
  method: 'GET',
  headers: {
    'X-API-Key': 'your_api_key',
    'X-API-Secret': 'your_secret'
  }
})
.then(res => res.json())
.then(console.log);

Resize Image

Resize an image to custom dimensions or a predefined size preset. Upload the file as multipart/form-data.

Form Parameters

Resize Modes

• fit (default): Fit within bounds maintaining aspect ratio
• fill: Fill entire area, cropping if necessary
• stretch: Stretch to exact dimensions
• crop: Smart cropping to fit aspect ratio

cURL Example

curl -X POST "https://api.chemhub.com/api/v1/img_resizer/resize" \
  -H "X-API-Key: your_api_key" \
  -H "X-API-Secret: your_secret" \
  -F "file=@image.jpg" \
  -F "width=1024" \
  -F "height=768" \
  -F "resize_mode=fit" \
  -F "quality=90" \
  -F "output_format=jpeg" \
  --output resized_image.jpg

Code Examples

import requests

url = "https://api.chemhub.com/api/v1/img_resizer/resize"

headers = {
    "X-API-Key": "your_api_key",
    "X-API-Secret": "your_secret"
}

with open("image.jpg", "rb") as f:
    files = {"file": f}
    data = {
        "width": 1024,
        "height": 768,
        "resize_mode": "fit",
        "quality": 90,
        "output_format": "jpeg"
    }
    response = requests.post(url, headers=headers, files=files, data=data)

if response.status_code == 200:
    with open("resized_image.jpg", "wb") as out:
        out.write(response.content)
    print("Image resized successfully!")
else:
    print(response.json())

const form = new FormData();
form.append('file', fileInput.files[0]);
form.append('width', '1024');
form.append('height', '768');
form.append('resize_mode', 'fit');
form.append('quality', '90');
form.append('output_format', 'jpeg');

fetch('https://api.chemhub.com/api/v1/img_resizer/resize', {
  method: 'POST',
  headers: {
    'X-API-Key': 'your_api_key',
    'X-API-Secret': 'your_secret'
  },
  body: form
})
.then(async res => {
  if (res.ok) {
    const blob = await res.blob();
    const url = URL.createObjectURL(blob);
    console.log('Resized image URL:', url);
  } else {
    console.log(await res.json());
  }
});

Get Image Info

Get information about an uploaded image without resizing. Upload the file as multipart/form-data.

Form Parameters

• file: File, Image file (required) — PNG, JPEG, WebP, BMP, or TIFF

Response

{
  "success": true,
  "info": {
    "width": 1920,
    "height": 1080,
    "format": "JPEG",
    "mode": "RGB",
    "file_size_bytes": 245760,
    "aspect_ratio": 1.7778
  },
  "standard_sizes": {
    "thumbnail": [150, 150],
    "small": [300, 300],
    "medium": [600, 600]
  }
}

cURL Example

curl -X POST "https://api.chemhub.com/api/v1/img_resizer/info" \
  -H "X-API-Key: your_api_key" \
  -H "X-API-Secret: your_secret" \
  -F "file=@image.jpg"

Size Presets

Predefined sizes for common use cases. Pass the preset name as the size_preset form parameter.

Python SDK

Complete Python SDK with custom resize, preset resize, and image info endpoints.

import requests
import os
from pathlib import Path

BASE_URL = "https://api.chemhub.com/api/v1"
API_KEY = "YOUR_API_KEY"
API_SECRET = "YOUR_API_SECRET"

headers = {
    "X-API-Key": API_KEY,
    "X-API-Secret": API_SECRET
}

# --- Health Check ---
def check_health():
    return requests.get(f"{BASE_URL}/img_resizer/health", headers=headers).json()

# --- Resize to custom dimensions ---
def resize_image(image_path, width=800, height=600, resize_mode="fit", quality=85, output_format="jpeg"):
    with open(image_path, "rb") as image_file:
        files = {"file": image_file}
        data = {
            "width": width,
            "height": height,
            "resize_mode": resize_mode,
            "quality": quality,
            "output_format": output_format
        }
        response = requests.post(
            f"{BASE_URL}/img_resizer/resize",
            headers=headers,
            files=files,
            data=data
        )

    if response.status_code == 200:
        output_path = str(Path(image_path).with_suffix("")) + f"_resized_{width}x{height}.{output_format}"
        with open(output_path, "wb") as f:
            f.write(response.content)
        print(f"Image resized! Saved to: {output_path}")
        return output_path
    else:
        print(f"Error: {response.status_code} - {response.text}")
        return None

# --- Resize using a size preset ---
def resize_with_preset(image_path, size_preset="medium", resize_mode="fit", quality=85, output_format="jpeg"):
    with open(image_path, "rb") as image_file:
        files = {"file": image_file}
        data = {
            "size_preset": size_preset,
            "resize_mode": resize_mode,
            "quality": quality,
            "output_format": output_format
        }
        response = requests.post(
            f"{BASE_URL}/img_resizer/resize",
            headers=headers,
            files=files,
            data=data
        )

    if response.status_code == 200:
        output_path = str(Path(image_path).with_suffix("")) + f"_resized_{size_preset}.{output_format}"
        with open(output_path, "wb") as f:
            f.write(response.content)
        print(f"Image resized! Saved to: {output_path}")
        return output_path
    else:
        print(f"Error: {response.status_code} - {response.text}")
        return None

# --- Get image info ---
def get_image_info(image_path):
    with open(image_path, "rb") as image_file:
        files = {"file": image_file}
        response = requests.post(
            f"{BASE_URL}/img_resizer/info",
            headers=headers,
            files=files
        )
    return response.json()

# --- Test all endpoints ---
if __name__ == "__main__":
    image_path = "image1.jpeg"

    print("=== IMAGE RESIZER API TEST ===")

    health = check_health()
    print(f"Health: {health.get('status', 'unknown')}")

    info = get_image_info(image_path)
    print(f"Info: {info.get('info', {})}")

    print("\n1. Resizing image to 800x600 (fit mode):")
    resize_image(image_path, width=800, height=600, resize_mode="fit", quality=85, output_format="jpeg")

    print("\n2. Resizing image using 'thumbnail' preset:")
    resize_with_preset(image_path, size_preset="thumbnail", resize_mode="fit", quality=95, output_format="jpeg")

Errors & Status Codes

Error Response Format

{
  "success": false,
  "error": "Invalid dimensions",
  "message": "Target size must be between 16x16 and 5000x5000"
}

Status Codes

Limitations