fix: 修复README

README.md

@@ -21,6 +21,53 @@ Convenient and fast library building tools.
 * NDK-18: android-ndk-r18b
 * MacOS
 
+## Help
+
+```
+❯ ./android.sh -h
+
+'android.sh' builds some lib for Android platform. By default five Android ABIs (armeabi-v7a, armeabi-v7a-neon, arm64-v8a, x86 and x86_64) are built without any external libraries enabled. Options can be used to disable ABIs and/or enable external libraries.
+
+Usage: ./android.sh [OPTION]...
+
+Specify environment variables as VARIABLE=VALUE to override default build options.
+
+Options:
+  -h, --help			display this help and exit
+  -v, --version			display version information and exit
+  -c, --clean			clean build and prebuilt and exit
+  -cb, --clean build		clean build and exit
+  -cp, --clean prebuil		clean prebuilt and exit
+Platforms:
+  --arch-all			do build armeabi-v7a, armeabi-v7a-neon, arm64-v8a, x86 and x86_64 platform [yes]
+  --arch-armeabi-v7a		do build armeabi-v7a platform [yes]
+  --arch-armeabi-v7a-neon	do build armeabi-v7a-neon platform [yes]
+  --arch-arm64-v8a		do build arm64-v8a platform [yes]
+  --arch-x86			do build x86 platform [yes]
+  --arch-x86_64			do build x86_64 platform [yes]
+
+Libraries:
+  --enable-libname			build with libname libraries
+
+  				support libs : ffmpeg gsm iconv lame libdsm libtasn1 openjpeg openssl zlib
+
+  				note: openssl library must be compiled independently
+
+FFmpeg Configs:
+  --ffmpeg-config-lite		build ffmpeg with lite config
+  --ffmpeg-config-mp4		build ffmpeg with mp4 config
+  --ffmpeg-config-mp3		build ffmpeg with mp3 config
+  --ffmpeg-config-min		build ffmpeg with min config
+
+GPL libraries:
+  --lib-x264			build with x264 [no]
+  --lib-x265			build with x265 [no]
+
+Autohr:
+  name				biezhihua
+  email				biezhihua@gmail.com
+```
+
 ## Guide
 
 ```