Compile ffmpeg in Mac OS environment to generate so library file

Compiler Environment:

Mac OS monterey (12.3.1)
android-ndk (21.0.6113669)
ffmpeg-4.2.2

Download ffmpeg: wget https://ffmpeg.org/releases/ffmpeg-4.2.2.tar.bz2, or download it from the official git.

Note: The ndk version I am using is 21.0.6113669. I have tried version 24.0.8215888. The lack of certain files will cause the compilation to fail. It should be possible if the larger version is 21, but the specific reason has not been verified.

Note: After Android NDK r17c, Google officially removed GCC and no longer supports GCC. New versions of NDK are compiled using CLANG. So we use CLANG for compilation here.

1. Configure script
Add cross_prefix_clang parameter
Open (note: do not double-click to run) the configure file in the root directory of ffmpeg-4.2.2, search for CMDLINE_SET, you can find the following code, and then add a command line option: cross_prefix_clang


CMDLINE_SET="
    $PATHS_LIST
    ar
    arch
    as
    assert_level
    build_suffix
    cc
    objcc
    cpu
    cross_prefix
    # 新增命令行参数
    cross_prefix_clang
    custom_allocator
    cxx
    dep_cc
    doxygen
    env
    extra_version
    .
    .
    .

2. Modify the compilation tool path settings,

Search ar_default="${cross_prefix}${ar_default}"

ar_default="${cross_prefix}${ar_default}"
cc_default="${cross_prefix}${cc_default}"
cxx_default="${cross_prefix}${cxx_default}"
nm_default="${cross_prefix}${nm_default}"

将中间两行改成

ar_default="${cross_prefix}${ar_default}"
cc_default="${cross_prefix_clang}${cc_default}"
cxx_default="${cross_prefix_clang}${cxx_default}"
nm_default="${cross_prefix}${nm_default}"

Create a new compilation configuration script

Create a new shell script in the root directory and name it: build_android_clang.sh

#!/bin/bash
set -x
# 目标Android版本
API=24
CPU=armv7-a
#so库输出目录，自己喜欢放哪里就放哪里
# OUTPUT=$(pwd)/android/$CPU
OUTPUT=./output/$CPU
# NDK的路径，根据自己的NDK位置进行设置
NDK=/Users/kbq/Library/Android/sdk/ndk/21.0.6113669
# 编译工具链路径
TOOLCHAIN=$NDK/toolchains/llvm/prebuilt/darwin-x86_64
# 编译环境
SYSROOT=$TOOLCHAIN/sysroot
 
function build
{
  ./configure \
  --prefix=$OUTPUT \
  --target-os=android \
  --arch=arm \
  --cpu=armv7-a \
  --enable-asm \
  --enable-neon \
  --enable-cross-compile \
  --enable-shared \
  --disable-static \
  --disable-doc \
  --disable-ffplay \
  --disable-ffprobe \
  --disable-symver \
  --disable-ffmpeg \
  --sysroot=$SYSROOT \
  --cross-prefix=$TOOLCHAIN/bin/arm-linux-androideabi- \
  --cross-prefix-clang=$TOOLCHAIN/bin/armv7a-linux-androideabi$API- \
  --extra-cflags="-fPIC"
 
  make clean all
  # 这里是定义用几个CPU编译
  make -j12
  make install
  
}

build

The third step starts compilation

Open the cmd terminal and cd to the directory where FFmpeg is located

Type ./build_android_clang.sh

Waiting for the compilation to be completed, you will get two directories, include and lib, in the ffmpeg/android/armv7-a directory, which are header files and so library files respectively.

Note: If the error message zsh: permission denied: ./build_android_clang.sh appears, it means the file permissions are incorrect. Execute chmod u+x build_android_clang.sh

Compile ffmpeg in Mac OS environment to generate so library file

Create a new compilation configuration script

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