Compress PNG Files in a Directory or a Single PNG File with pngquant

This function compresses either a single PNG file or all PNG files in a specified directory using pngquant optimization to reduce file size while maintaining visual quality. pngquant is a lossy compression tool that can reduce file sizes by up to 70% while preserving full alpha transparency.

Usage

compress_png(path, png_overwrite = TRUE, speed = 1, verbosity = TRUE)

Arguments

path: A string specifying either the path to a single PNG file or a directory containing PNG files.
png_overwrite: Logical. If TRUE, will overwrite existing files. Default is TRUE
speed: Integer. Speed/quality trade-off from 1 (brute-force) to 10 (fastest). Default is 3. Speed 10 has 5% lower quality but is 8 times faster.
verbosity: Logical. Controls the amount of information displayed. FALSE = minimal, TRUE = detailed. Default is TRUE.

Value

For single files, returns a list with compression statistics. For directories, returns a data frame with statistics for all files. The function also works by side effect, compressing PNG files.

Examples

# Compress all PNG files in a directory
# compress_png("path/to/your/folder")

# Compress a single PNG file
# compress_png("path/to/your/image.png")

# Compress with automatic installation if pngquant is not found
# compress_png("path/to/your/folder", auto_install = TRUE)

# Compress and overwrite existing files
# compress_png("path/to/your/folder", force = TRUE)