tce-load -i compiletc tiff-dev libpng-dev giflib-dev

wget https://storage.googleapis.com/downloads.webmproject.org/releases/webp/libwebp-1.4.0.tar.gz

cd libwebp-1.4.0

CC="gcc -flto -march=armv8-a+crc -mtune=cortex-a72 -Os -pipe" CXX="g++ -flto -march=armv8-a+crc -mtune=cortex-a72 -Os -pipe -fno-exceptions -fno-rtti" ./configure --prefix=/usr/local --localstatedir=/var --enable-shared --disable-static --enable-libwebpmux --enable-libwebpdemux --enable-libwebpdecoder --enable-libwebpextras --enable-swap-16bit-csp

find . -name Makefile -type f -exec sed -i 's/-g -O2//g' {} \;

make [2m 47.24s]
sudo make install

Tools:
cwebp : yes
  Input format support
  ====================
  JPEG : yes
  PNG  : yes
  TIFF : yes
  WIC  : no
dwebp : yes
  Output format support
  =====================
  PNG  : yes
  WIC  : no
GIF support : yes
anim_diff   : yes
gif2webp    : yes
img2webp    : yes
webpmux     : yes
vwebp       : no
webpinfo    : yes
SDL support : no
vwebp_sdl   : no