INSTALL

## Compiling on Linux, *BSD and macOS

(For instructions for Windows see section below.)

### Using GNU/Makefile

To get the code:

    git clone --recursive https://github.com/kornelski/pngquant.git

You will need libpng installed with development headers.
On Linux install `libpng-dev` package. On macOS `brew install libpng`.

There's an optional `./configure` step (see sections below). Run:

    make

It will create `pngquant` executable in the current directory. If you'd like
to install it system-wide:

    sudo make install

By default it will be installed in /usr/local/bin. To install it in another
directory run `./configure --prefix=dir && make`.

pngquant uses GNU Makefile. To compile on FreeBSD you will need to use `gmake`.

Avoid Linux distros that ship with libpng 1.2. It is old and buggy.
Use libpng 1.6 or later.

### Using Rust/Cargo

If you have Rust, you can also build with `cargo build`.

### Custom static libpng

Extract libpng source code as a *sub*directory of pngquant source directory.
Build static libpng (`./configure --enable-static && make`), and then
`./configure && make` pngquant.

When building with Cargo, `export PNG_STATIC=1`.

## Windows

Compiling on Windows is supported only via Rust/Cargo.

 1. Install git (msys-git).
 2. Install Visual C++ 2015 Build Tools.
 3. [Install Rust](https://www.rust-lang.org/install.html)
 4. Restart Windows.

Open Git's Bash prompt and run:

    git clone -b msvc --recursive https://github.com/kornelski/pngquant.git
    cd pngquant

This will create pngquant folder in your user folder. And then run:

    cargo build --release

It will create `pngquant.exe` in `target/release` subfolder.

## Compilation with OpenMP

    cargo build --release --features=openmp # or
    cargo build --release --features=openmp-static

On macOS you may need to install gcc and run `export CC=gcc-7` first,
because clang doesn't support OpenMP (yet).

## Compilation without Cocoa image reader

macOS version can use Cocoa to read images. This adds support for color profiles
and other image formats as input.

    cargo build --release --features=cocoa

## Compilation with Little CMS 2

Little CMS library is used by default.

It's linked dynamically if `pkg-config` is working (e.g. install `liblcms2-dev`).
Otherwise uses static build as a fallback.

Set `export LCMS2_STATIC=1` to force static linking.

## Compilation of `libimagequant.a` only

If you want to use pngquant's conversion algorithm without loading/saving PNG
files, then you can run `make` or `cargo build` in the `lib/` directory.

The library doesn't need libpng nor zlib.