1新建build_android.sh文件，内容如下
#!/usr/bin/env bash
# 当前系统
export HOST_TAG=darwin-x86_64
# 支持的 Android CUP 架构
# export ARCH=aarch64
# export CPU=armv8-a
export ARCH=armv7a
export CPU=armv7-a
# 支持的 Android 最低系统版本
export MIN=21
export ANDROID_NDK_PLATFORM=android-21
export PREFIX=$(pwd)/android/$CPU
# NDK 根目录
export NDK=/Users/xusu/Library/Android/sdk/ndk-bundle
export MIN_PLATFORM=$NDK/platforms/android-$MIN
export SYSROOT=$NDK/sysroot
export TOOLCHAIN=$NDK/toolchains/llvm/prebuilt/$HOST_TAG
export AR=$TOOLCHAIN/bin/arm-linux-androideabi-ar
export AS=$TOOLCHAIN/bin/arm-linux-androideabi-as
export CC=$TOOLCHAIN/bin/$ARCH-linux-androideabi$MIN-clang
export CXX=$TOOLCHAIN/bin/$ARCH-linux-androideabi$MIN-clang++
export LD=$TOOLCHAIN/bin/arm-linux-androideabi-ld
export NM=$TOOLCHAIN/bin/arm-linux-androideabi-nm
export RANLIB=$TOOLCHAIN/bin/arm-linux-androideabi-ranlib
export STRIP=$TOOLCHAIN/bin/arm-linux-androideabi-strip
FF_EXTRA_CFLAGS=""
# FF_CFLAGS="-O3 -Wall -pipe -ffast-math -fstrict-aliasing -Werror=strict-aliasing -Wno-psabi -Wa,--noexecstack -DANDROID "
# FF_CFLAGS="-DANDROID -I$SYSROOT/usr/include"
# FF_LDFLAGS=" -shared -rpath-link=$MIN_PLATFORM/arch-arm64/usr/lib -L$MIN_PLATFORM/arch-arm64/usr/lib -nostdlib -fPIC -shared -pie -p -shared"
# OPTIMIZE_CFLAGS="-I$NDK/sysroot/usr/include -mfloat-abi=softfp -mfpu=vfp -marm -march=$CPU -DANDROID_PLATFORM=android-21"
OPTIMIZE_CFLAGS="-DANDROID -I$NDK/sysroot/usr/include/arm-linux-androideabi/"
# ADDI_LDFLAGS="-shared -rpath-link=$SYSROOT/usr/lib/aarch64-linux-android -L$SYSROOT/usr/lib/aarch64-linux-android -fuse-ld=bfd"
# ADDI_LDFLAGS="-Wl,-rpath-link=$MIN_PLATFORM/arch-arm/usr/lib -Wl,-rpath-link=$TOOLCHAIN/lib/gcc/arm-linux-androideabi/4.9.x/armv7-a -L$MIN_PLATFORM/arch-arm/usr/lib -L$TOOLCHAIN/lib/gcc/arm-linux-androideabi/4.9.x/armv7-a"
ADDI_LDFLAGS="-Wl,-rpath-link=$MIN_PLATFORM/arch-arm/usr/lib -L$MIN_PLATFORM/arch-arm/usr/lib -nostdlib"
sed -i "" "s/SLIBNAME_WITH_MAJOR='\$(SLIBNAME).\$(LIBMAJOR)'/SLIBNAME_WITH_MAJOR='\$(SLIBPREF)\$(FULLNAME)-\$(LIBMAJOR)\$(SLIBSUF)'/" configure
sed -i "" "s/LIB_INSTALL_EXTRA_CMD='\$\$(RANLIB) \"\$(LIBDIR)\\/\$(LIBNAME)\"'/LIB_INSTALL_EXTRA_CMD='\$\$(RANLIB) \"\$(LIBDIR)\\/\$(LIBNAME)\"'/" configure
sed -i "" "s/SLIB_INSTALL_NAME='\$(SLIBNAME_WITH_VERSION)'/SLIB_INSTALL_NAME='\$(SLIBNAME_WITH_MAJOR)'/" configure
sed -i "" "s/SLIB_INSTALL_LINKS='\$(SLIBNAME_WITH_MAJOR) \$(SLIBNAME)'/SLIB_INSTALL_LINKS='\$(SLIBNAME)'/" configure
# sed -i "" "s/SHFLAGS='-shared -Wl,-soname,\$(SLIBNAME)'/SHFLAGS='-shared -soname \$(SLIBNAME)'/" configure
# sed -i "" "s/-Wl//g" configure
# --sysroot=$SYSROOT \
# --ld=$LD \
./configure \
--prefix=$PREFIX \
--ar=$AR \
--as=$AS \
--cc=$CC \
--cxx=$CXX \
--nm=$NM \
--ranlib=$RANLIB \
--strip=$STRIP \
--arch=$ARCH \
--target-os=android \
--enable-cross-compile \
--disable-asm \
--enable-shared \
--disable-static \
--disable-ffprobe \
--disable-ffplay \
--disable-ffmpeg \
--disable-debug \
--disable-symver \
--disable-stripping \
--extra-cflags="-Os -fpic $OPTIMIZE_CFLAGS" \
--extra-ldflags="$ADDI_LDFLAGS"
# --extra-cflags="$FF_EXTRA_CFLAGS $FF_CFLAGS" \
# --extra-ldflags="$FF_LDFLAGS"
sed -i "" "s/#define HAVE_TRUNC 0/#define HAVE_TRUNC 1/" config.h
sed -i "" "s/#define HAVE_TRUNCF 0/#define HAVE_TRUNCF 1/" config.h
sed -i "" "s/#define HAVE_RINT 0/#define HAVE_RINT 1/" config.h
sed -i "" "s/#define HAVE_LRINT 0/#define HAVE_LRINT 1/" config.h
sed -i "" "s/#define HAVE_LRINTF 0/#define HAVE_LRINTF 1/" config.h
sed -i "" "s/#define HAVE_ROUND 0/#define HAVE_ROUND 1/" config.h
sed -i "" "s/#define HAVE_ROUNDF 0/#define HAVE_ROUNDF 1/" config.h
sed -i "" "s/#define HAVE_CBRT 0/#define HAVE_CBRT 1/" config.h
sed -i "" "s/#define HAVE_CBRTF 0/#define HAVE_CBRTF 1/" config.h
sed -i "" "s/#define HAVE_COPYSIGN 0/#define HAVE_COPYSIGN 1/" config.h
sed -i "" "s/#define HAVE_ERF 0/#define HAVE_ERF 1/" config.h
sed -i "" "s/#define HAVE_HYPOT 0/#define HAVE_HYPOT 1/" config.h
sed -i "" "s/#define HAVE_ISNAN 0/#define HAVE_ISNAN 1/" config.h
sed -i "" "s/#define HAVE_ISFINITE 0/#define HAVE_ISFINITE 1/" config.h
sed -i "" "s/#define HAVE_INET_ATON 0/#define HAVE_INET_ATON 1/" config.h
sed -i "" "s/#define getenv(x) NULL/\\/\\/ #define getenv(x) NULL/" config.h
2.修改NDK 根目录
3.将该文件放在ffmpeg-4.2.1解压后的文件内
4.开始编译步骤
4.1. chmod 777 build_android.sh
4.2. ./ build_android.sh
4.3. make -j 4
4.4. make install
4.5. android目录即为编译的结果
如果大家编译过程遇到啥问题，可以评论一起交流，毕竟都是在一堆错误中成长的。
网友评论