This crate provides decoding/encoding for Blizzard BLP texture format that is used across several games like Wacraft III and World of Warcraft. You can load any BLP file into DynamicImage from image crate and save any DynamicImage into BLP file.

Usage

This crate is on crates.io and can be used by adding image-blp to your dependencies in your project's Cargo.toml.

[dependencies]
image-blp = "1"

Example: loading

The crate separates loading of BLP file into parsing and converting. That allows to process BLP files without loosing information due unessesary conversion back and forth. Typically loading of BLP image into usable RGBA image looks like:

let blp_file = load_blp(blp_filename).expect("loaded blp");
let mipmap_level = 0;
let image = blp_to_image(&blp_file, mipmap_level).expect("converted");

See example examples/load.rs for full code.

Example: saving

The crate provides simplified API for specifing which type of BLP do you want to use. See convert::BlpTarget type for more info. Here the typical way to save image as

let img_file: DynamicImage = Reader::open(input_filename)
    .expect("open")
    .decode()
    .expect("decode");
let make_mipmaps = true;
let blp = image_to_blp(
    img_file,
    make_mipmaps,
    BlpTarget::Blp1(BlpOldFormat::Raw1 {
        alpha_bits: AlphaBits::Bit1,
    }),
    FilterType::Nearest,
)
.expect("converted");
save_blp(&blp, output_filename).expect("saved");

See example examples/save.rs for full code.

CLI tool

The library is used to build universal CLI tool blp-conv that allows to convert from/into BLP format for wide range of image formats. You can install it via:

cargo install blp-conv

Features

The crate supports all known BLP versions like:

• BLP0 -- is used in old Wacraft III ROC Beta builds.
• BLP1 -- is common for Wacraft III TFT.
• BLP2 -- is used in World of Warcraft.

The crate supports also all known encodings:

• RAW1 -- paletted images with 256 colors. We use color_quant package for compressing generic images to the format.
• RAW3 -- like ordinary RGBA bitmaps.
• JPEG -- ordinary jpeg compressed image.
• DXTn -- S3TC compression algorithms for BLP2 version. We use texpresso for the compression/decompression.

Tests

Tests of the library use original files of Blizzard games. So, they cannot be distributed with the library due license issues. You should buy the original games to extract the files for testing.