PepeCore

A Rust library for image decoding, encoding, and processing using an efficient SVec data structure.

PepeCore provides:

• SVec – high-performance, image buffers (array::svec::SVec).
• Image decoding – read images from file paths or in-memory buffers (read::read_in_path, read::read_in_buffer).
• Image saving – write SVec images to disk in common formats (save::svec_save).
• Color conversions – dynamic RGB ↔ grayscale, YCbCr, CMYK, and channel swaps via cvt_color.
• Halftone effects – apply dot-based halftoning (halftone, rotate_halftone).
• Screentone effects – comic-style dot screening (screentone, rotate_screentone).
• (Experimental) Color levels adjustment – coming soon.

Installation

Add PepeCore to your Cargo.toml:

[dependencies]
pepecore = "0.1"

Then in your crate:

extern crate pepecore;
use pepecore::{svec::SVec, read::read_in_path, save::svec_save};
use pepecore::{cvt_color, halftone, screentone};
use pepecore::enums::{ImgColor, CVTColor, DotType};

Quick Start

use pepecore::{
    svec::SVec,
    read::read_in_path,
    save::svec_save,
    cvt_color,
    screentone,
    enums::{ImgColor, CVTColor, DotType},
};

fn main() -> Result<(), Box<dyn std::error::Error>> {
    // 1. Decode an image file as RGB
    let mut img: SVec = read_in_path("input.jpg", ImgColor::RGB)?;
    
    // 2. Convert RGB → Grayscale (BT.709)
    cvt_color(&mut img, CVTColor::RGB2Gray_709);
    
    // 3. Apply a screentone effect (dot pattern 8×8)
    screentone(&mut img, 8, &DotType::Square);

    // 4. Save the processed image
    svec_save(img, "output.png")?;

    Ok(())
}

Features

Decoding

• Flexible input: file paths or raw byte buffers.
• PSD support: reads both layered and flattened PSD files.
• Dynamic types: returns either u8, u16, or f32 data.

Saving

• Handles Luma, LumaA, Rgb, Rgba in u8, u16, and f32 formats.
• Converts floating-point to u8 with simple scaling (×255).

Color Conversion

Use cvt_color(&mut img, CVTColor::…) to:

• Convert between RGB, Grayscale (BT.601/709/2020), YCbCr, CMYK.
• Swap channels (RGB ↔ BGR).
• Expand Gray → RGB.

Halftone & Screentone

• Halftone dot screening with configurable dot sizes per channel.
• Rotate capability for angled halftones.
• Screentone for single-channel comic-style screening, with optional rotation.

Color Levels (Experimental)

The color_levels API is not yet fully implemented. Stay tuned for fine-grained black/white point and gamma adjustments.