iOS port of opencore-amr
Refer to README for opencore-amr info which is from original package.
Run ./configure then build_ios.sh to build.
Then use opencore-amrnb.framework or opencore-amrwb.framework
packaging refer to https://www.jianshu.com/p/9eef3afdae11
Build_ios.sh is modified from https://chromium.googlesource.com/webm/libwebp/+/refs/heads/master/iosbuild.sh
For AMR-WB encoding, refer to http://sourceforge.net/projects/opencore-amr/files/vo-amrwbenc/ or AMR Codecs as Shared Libraries http://www.penguin.cz/~utx/amr