Emscripten 实现 ncnn-webassembly-scrfd windows10

来源：https://zhuanlan.zhihu.com/p/372332267

代码链接：https://github.com/nihui/ncnn-webassembly-scrfd

1、安装 emsripten

git clone https://github.com/emscripten-core/emsdk.git
cd emsdk
./emsdk install 2.0.8
./emsdk activate 2.0.8

source emsdk/emsdk_env.sh

2、下载 ncnn webassembly包：cmake时需要

可以手动下载，将结果解压到build文件夹。在ncnn-webassembly-scrfd项目下CMakeLists中指定了该文件的位置。

wget https://github.com/nihui/ncnn/releases/download/20210519/ncnn-20210519-webassembly.zip
unzip ncnn-20210519-webassembly.zip

3、编译四个 WASM feature variants：

windows10下稍微有点不同。

cmake -G "MinGW Makefiles" -DCMAKE_TOOLCHAIN_FILE=%EMSDK%/upstream/emscripten/cmake/Modules/Platform/Emscripten.cmake -DWASM_FEATURE=basic ..
make -j4
cmake -G "MinGW Makefiles" -DCMAKE_TOOLCHAIN_FILE=$EMSDK/upstream/emscripten/cmake/Modules/Platform/Emscripten.cmake -DWASM_FEATURE=simd ..
make -j4
cmake -G "MinGW Makefiles" -DCMAKE_TOOLCHAIN_FILE=$EMSDK/upstream/emscripten/cmake/Modules/Platform/Emscripten.cmake -DWASM_FEATURE=threads ..
make -j4
cmake -G "MinGW Makefiles" -DCMAKE_TOOLCHAIN_FILE=$EMSDK/upstream/emscripten/cmake/Modules/Platform/Emscripten.cmake -DWASM_FEATURE=simd-threads ..
make -j4