如何使用libx265为Android编译FFmpeg

How to compile FFmpeg with libx265 for Android?

本文关键字：编译 FFmpeg Android 何使用 libx265 更新时间：2023-10-16

我已经成功地用libx264（作为静态库）为Android编译了FFmpeg。但我也想在Android上的FFmpeg中使用libx265（作为静态库）。所以我做了一些尝试：

首先，我修复了libx265的log2函数和posix_memalign函数没有发现的问题，将它们改为log（使用log来近似log2）函数和memalign（替换posix_mealig并进行一些调整）函数。并通过删除cmakelist.txt文件中的"-lpthread"修复了pthread链接问题。

然后，我使用cmake和make成功地编译了libx265（作为静态库）。

我在配置FFmpeg时启用了libx265。但是当configure运行时，它在屏幕上显示"使用pkg config找不到libx265"。

我检查了config.log，发现了以下错误消息：

/home/user/ffmpeg-2.8.1/android/arm/lib/libx265.a(bitstream.cpp.o):bitstream.cpp:typeinfo for x265::BitInterface: error: undefined reference to 'vtable for __cxxabiv1::__class_type_info'
/home/user/ffmpeg-2.8.1/android/arm/bin/../lib/gcc/arm-linux-androideabi/4.9/../../../../arm-linux-androideabi/bin/ld: the vtable symbol may be undefined because the class is missing its key function
/home/user/ffmpeg-2.8.1/android/arm/lib/libx265.a(bitstream.cpp.o):bitstream.cpp:typeinfo for x265::Bitstream: error: undefined reference to 'vtable for __cxxabiv1::__si_class_type_info'
/home/user/ffmpeg-2.8.1/android/arm/bin/../lib/gcc/arm-linux-androideabi/4.9/../../../../arm-linux-androideabi/bin/ld: the vtable symbol may be undefined because the class is missing its key function
/home/user/ffmpeg-2.8.1/android/arm/lib/libx265.a(encoder.cpp.o):encoder.cpp:typeinfo for x265::SEIDecodedPictureHash: error: undefined reference to 'vtable for __cxxabiv1::__si_class_type_info'
/home/user/ffmpeg-2.8.1/android/arm/bin/../lib/gcc/arm-linux-androideabi/4.9/../../../../arm-linux-androideabi/bin/ld: the vtable symbol may be undefined because the class is missing its key function
/home/user/ffmpeg-2.8.1/android/arm/lib/libx265.a(encoder.cpp.o):encoder.cpp:typeinfo for x265::SEIuserDataUnregistered: error: undefined reference to 'vtable for __cxxabiv1::__si_class_type_info'
/home/user/ffmpeg-2.8.1/android/arm/bin/../lib/gcc/arm-linux-androideabi/4.9/../../../../arm-linux-androideabi/bin/ld: the vtable symbol may be undefined because the class is missing its key function
/home/user/ffmpeg-2.8.1/android/arm/lib/libx265.a(encoder.cpp.o):encoder.cpp:typeinfo for x265::SEIMasteringDisplayColorVolume: error: undefined reference to 'vtable for __cxxabiv1::__si_class_type_info'
/home/user/ffmpeg-2.8.1/android/arm/bin/../lib/gcc/arm-linux-androideabi/4.9/../../../../arm-linux-androideabi/bin/ld: the vtable symbol may be undefined because the class is missing its key function
/home/user/ffmpeg-2.8.1/android/arm/lib/libx265.a(threading.cpp.o):threading.cpp:typeinfo for x265::Thread: error: undefined reference to 'vtable for __cxxabiv1::__class_type_info'
/home/user/ffmpeg-2.8.1/android/arm/bin/../lib/gcc/arm-linux-androideabi/4.9/../../../../arm-linux-androideabi/bin/ld: the vtable symbol may be undefined because the class is missing its key function
/home/user/ffmpeg-2.8.1/android/arm/lib/libx265.a(wavefront.cpp.o):wavefront.cpp:typeinfo for x265::JobProvider: error: undefined reference to 'vtable for __cxxabiv1::__class_type_info'
/home/user/ffmpeg-2.8.1/android/arm/bin/../lib/gcc/arm-linux-androideabi/4.9/../../../../arm-linux-androideabi/bin/ld: the vtable symbol may be undefined because the class is missing its key function
/home/user/ffmpeg-2.8.1/android/arm/lib/libx265.a(slicetype.cpp.o):slicetype.cpp:typeinfo for x265::BondedTaskGroup: error: undefined reference to 'vtable for __cxxabiv1::__class_type_info'
/home/user/ffmpeg-2.8.1/android/arm/bin/../lib/gcc/arm-linux-androideabi/4.9/../../../../arm-linux-androideabi/bin/ld: the vtable symbol may be undefined because the class is missing its key function
/home/user/ffmpeg-2.8.1/android/arm/lib/libx265.a(frameencoder.cpp.o):frameencoder.cpp:function x265::FrameEncoder::encodeSlice(): error: undefined reference to '__dynamic_cast'
/home/user/ffmpeg-2.8.1/android/arm/lib/libx265.a(frameencoder.cpp.o):frameencoder.cpp:function x265::FrameEncoder::encodeSlice(): error: undefined reference to '__dynamic_cast'
/home/user/ffmpeg-2.8.1/android/arm/lib/libx265.a(frameencoder.cpp.o):frameencoder.cpp:function x265::FrameEncoder::processRowEncoder(int, x265::ThreadLocalData&): error: undefined reference to '__dynamic_cast'
/home/user/ffmpeg-2.8.1/android/arm/lib/libx265.a(frameencoder.cpp.o):frameencoder.cpp:function .LTHUNK2: error: undefined reference to '__dynamic_cast'
/home/user/ffmpeg-2.8.1/android/arm/lib/libx265.a(frameencoder.cpp.o):frameencoder.cpp:typeinfo for x265::FrameEncoder: error: undefined reference to 'vtable for __cxxabiv1::__vmi_class_type_info'
/home/user/ffmpeg-2.8.1/android/arm/bin/../lib/gcc/arm-linux-androideabi/4.9/../../../../arm-linux-androideabi/bin/ld: the vtable symbol may be undefined because the class is missing its key function
/home/user/ffmpeg-2.8.1/android/arm/lib/libx265.a(sei.cpp.o):sei.cpp:typeinfo for x265::SEI: error: undefined reference to 'vtable for __cxxabiv1::__vmi_class_type_info'
/home/user/ffmpeg-2.8.1/android/arm/bin/../lib/gcc/arm-linux-androideabi/4.9/../../../../arm-linux-androideabi/bin/ld: the vtable symbol may be undefined because the class is missing its key function

我该怎么修？

我找到了解决方案。

我需要手动将"libgnustl_static.a"的路径添加到gcc/g++作为参数。完成后，编译将成功。

最近我遇到了错误，正如user3032481所说。

我修改ffmpeg的配置如下。

--extra-libs="-lother_libs -L/Users/shutup/Library/Android/sdk/ndk-bundle/sources/cxx-stl/gnu-libstdc++/4.9/libs/armeabi -lgnustl_static"

我想，原因是x265需要c++rtti功能，但android默认的libstdc++不包含它。所以我们需要添加libgnustl_static.