ImgByteSizer

ImgByteSizer is a command-line tool that precisely resizes and optimizes images to match a specific file size while maintaining the best possible quality.

Features

• 🎯 Resize images to an exact target file size
• 🖼️ Maintains aspect ratio during resizing
• 🔍 Intelligent quality optimization with binary search
• 🔄 Format conversion (JPEG, PNG, WebP)
• 📏 Minimum dimension constraints
• 🎨 Beautiful terminal output with progress indicators
• 📊 Detailed comparison of original vs. processed images

Installation

pip install imgbytesizer

Usage

imgbytesizer image.jpg 500KB

Basic Examples

# Resize an image to 500KB
imgbytesizer large_photo.jpg 500KB

# Resize and convert to WebP format
imgbytesizer image.png 1MB -f webp

# Specify output file path
imgbytesizer photo.jpg 1MB -o compressed_photo.jpg

# Ensure minimum dimension is at least 400px
imgbytesizer large_image.jpg 300KB --min-dimension 400

Command-Line Options

usage: imgbytesizer [-h] [-o OUTPUT] [-f {jpg,jpeg,png,webp}] [--min-dimension MIN_DIMENSION] [--no-exact] [--debug] [-q] [-v] [image_path] [target_size]

Resize an image to match a target file size

positional arguments:
  image_path            Path to the input image
  target_size           Target file size (e.g., "1MB", "500KB")

options:
  -h, --help            show this help message and exit
  -v, --version         Show version information

primary options:
  -o, --output OUTPUT   Output path (default: input_resized.ext)
  -f, --format {jpg,jpeg,png,webp}
                        Output format

advanced options:
  --min-dimension MIN_DIMENSION
                        Minimum width/height in pixels
  --no-exact            Do not pad file to get exact target size

utility:
  --debug               Enable debug logging
  -q, --quiet           Minimal output

examples:
  imgbytesizer image.jpg 500KB                   # Resize to 500 KB
  imgbytesizer photo.png 2MB -o small_photo.png  # Resize to 2 MB with custom output
  imgbytesizer image.jpg 100KB -f webp           # Resize and convert to WebP
  imgbytesizer large.jpg 50KB --min-dimension 200  # Ensure min dimension is 200px
  imgbytesizer -v                                # Show version information

How It Works

ImgByteSizer uses binary search algorithms to efficiently find the optimal combination of image dimensions and compression quality to match your target file size:

1. First attempts to adjust quality without resizing (for formats that support quality settings)
2. If quality adjustment alone isn't sufficient, performs binary search for optimal dimensions
3. Fine-tunes with an additional quality optimization pass
4. Adds minimal padding if necessary to hit the exact target size

The tool prioritizes maintaining the highest possible quality while meeting the target size constraint.

Example Output

❯ imgbytesizer image.png 1MB -f webp

◐ Opening image.png
  File: image.png
  Format: WEBP
  Dimensions: 1024 × 1024 pixels
  Size: 1.95 MB
  Target size: 1.00 MB
Trying quality adjustment without resizing...
Testing quality 100 |█████████████████░░░░░░░░░░░░░| 58% Size: 476.46 KB
✓ Found optimal quality: 100 (size: 476.46 KB)
Trying combined scaling and quality approach...
Trying scale factor 1.00 (1024×1024)...
Quality 100 |██████████████████████████████| 100% Size: 476.46 KB
Trying scale factor 1.25 (1280×1280)...
Quality 100 |██████████████████████████████| 100% Size: 680.51 KB
Trying scale factor 1.50 (1536×1536)...
Quality 100 |██████████████████████████████| 100% Size: 903.38 KB
Trying scale factor 2.00 (2048×2048)...
Quality 96 |██████████████████████████████| 100% Size: 1011.68 KB

✓ Combined approach success: scale=2.00, size=1011.68 KB
Adjusting to exact target size...
✓ Adjusted to exact size: 1.00 MB

╭─────────────┬────────────┬───────────────╮
│ Metric      │ Original   │ Processed     │
├─────────────┼────────────┼───────────────┤
│ Dimensions  │ 1024×1024  │ 2048×2048     │
├─────────────┼────────────┼───────────────┤
│ Size        │ 1.95 MB    │ 1.00 MB       │
├─────────────┼────────────┼───────────────┤
│ Target Size │            │ 1.00 MB       │
├─────────────┼────────────┼───────────────┤
│ Difference  │            │ 0 B (0.0%)    │
├─────────────┼────────────┼───────────────┤
│ Reduction   │            │ 48.8% smaller │
╰─────────────┴────────────┴───────────────╯
  Time taken: 28.12 seconds
  Output file: image_resized.webp

Real Use Cases

Web Development

# Create images that won't exceed page weight budget
imgbytesizer hero.jpg 200KB --min-dimension 1200
imgbytesizer background.png 100KB -f webp

Email Attachments

# Shrink images to fit email attachment limits
imgbytesizer family_photo.jpg 5MB

Social Media Uploads

# Optimize images for social media platforms with size limits
imgbytesizer profile_pic.jpg 400KB --min-dimension 400

Requirements

requires-python = ">=3.9"

dependencies = [
  "pillow (>=11.2.1,<12.0.0)",
  "pyfiglet (>=1.0.2,<2.0.0)",
  "tabulate (>=0.9.0,<0.10.0)",
]

Contributing

Contributions are welcome! Feel free to submit issues or pull requests.

License

This project is licensed under the MIT License - see the LICENSE file for details.