JSON Shake

A command-line tool to recursively extract and download all image URLs from JSON files. Supports macOS and Windows.

Installation

No installation required. Use the pre-compiled binaries:

• macOS: json-shake
• Windows: json-shake.exe

Usage

Basic Command

# macOS/Linux
./json-shake [options] <json-file-path>

# Windows
json-shake.exe [options] <json-file-path>

Options

• -limit <MB> - Maximum image size in MB (default: 0, no compression)
  • If set, images larger than the limit will be compressed to meet the size requirement
  • PNG and GIF images may be converted to JPEG for better compression

Examples

Download original images (no compression):

./json-shake data.json

Download with 1MB size limit:

./json-shake -limit 1 data.json

Download with 0.5MB size limit:

./json-shake -limit 0.5 data.json

Output Example

Without compression:

Found 18 image links
Output directory: /Users/username/Downloads/data
No size limit, downloading original images
Downloading images...
[1/18] Downloading: https://example.com/image1.png
✓ Downloaded: image1.png (0.64MB)
...
Download complete!
Success: 18, Failed: 0, Total: 18

With compression:

Found 18 image links
Output directory: /Users/username/Downloads/data
Image size limit: 1.00MB
Downloading images...
[1/18] Downloading: https://example.com/large-image.png
  Image size 5.65MB exceeds limit 1.00MB, compressing...
  Compressed from 5.65MB to 0.45MB (quality: 85)
✓ Downloaded: large-image.jpg (0.45MB)
...
Download complete!
Success: 18, Failed: 0, Total: 18

Output Location

Images are downloaded to:

• macOS: ~/Downloads/<json-filename>/
• Windows: C:\Users\<username>\Downloads\<json-filename>\

Supported Image Formats

• JPG/JPEG
• PNG
• GIF
• BMP
• WebP
• SVG

Features

• Recursively parses nested JSON structures
• Automatically detects image URLs (with or without file extensions)
• Batch downloads all images
• Configurable image compression - Set size limits to compress large images
• Intelligent quality adjustment - Automatically finds optimal compression quality
• Shows download progress with file sizes
• Skips already downloaded files
• Cross-platform support (macOS/Windows)

Building from Source

Requires Go 1.21 or higher:

# Build for current platform
go build -o json-shake main.go

# Cross-compile for Windows (from macOS/Linux)
GOOS=windows GOARCH=amd64 go build -o json-shake.exe main.go

# Cross-compile for macOS (from Windows)
set GOOS=darwin
set GOARCH=amd64
go build -o json-shake main.go

License

MIT License