vleschuk/woff2

This is a README for the font compression reference code. There are several compression related modules in this repository.

brotli/ contains reference code for the Brotli byte-level compression algorithm. Note that it is licensed under the MIT license.

src/ contains the C++ code for compressing and decompressing fonts.

Build & Run

This document documents how to run the compression reference code. At this writing, the code, while it is intended to produce a bytestream that can be reconstructed into a working font, the reference decompression code is not done, and the exact format of that bytestream is subject to change.

The build process depends on the g++ compiler.

Build

On a standard Unix-style environment:

git clone --recursive https://github.com/google/woff2.git
cd woff2
make clean all

Alternatively, if Brotli is already installed on your system you can use CMake to build executables and libraries:

git clone https://github.com/google/woff2.git
cd woff2
mkdir out
cd out
cmake ..
make
make install

By default, shared libraries are built. To use static linkage, do:

cd woff2
mkdir out-static
cmake -DBUILD_SHARED_LIBS=OFF ..
make
make install

JS build

To build for JS you need to perform the following steps:

1. Build and install brotli (https://github.com/google/brotli). For example to /usr/local/brotli (this path will be used later).

2. Install emsdk toolchain and import required variable by running

source emsdk_env.sh

3. Build js_brotli:

git clone https://github.com/vleschuk/js_brotli
cd js_brotli
mkdir out
cd out
cmake ..
make

Build will not finish successfully, that's expected result, however you should obtain the following bit-code files:

libbrotlidec-static.bc
libbrotlienc-static.bc
libbrotlicommon-static.bc

4. Finally build woff2 itself:

git clone https://github.com/vleschuk/woff2
cd woff2
mkdir out
cd out
EMSDK=/path/to/emsdk BROTLI=/path/to/brotli JS_BROTLI=/path/to/js_brotli ../configure_js.sh ..
make

Run

Ensure the binaries from the build process are in your $PATH, then:

woff2_compress myfont.ttf
woff2_decompress myfont.woff2

References

http://www.w3.org/TR/WOFF2/ http://www.w3.org/Submission/MTX/

Also please refer to documents (currently Google Docs):

WOFF Ultra Condensed file format: proposals and discussion of wire format issues (PDF is in docs/ directory)

WIFF Ultra Condensed: more discussion of results and compression techniques. This tool was used to prepare the data in that document.