MetaRTC-ffmpeg arm移植

touch cmake_arm.sh
添加

rm -rf build
mkdir build
cd build
ARCH=aarch64.cmake
cmake -DCMAKE_BUILD_TYPE=Release -DCMAKE_TOOLCHAIN_FILE=../$ARCH  ..
make

touch cmake_arm.sh
添加

SET(CMAKE_SYSTEM_NAME Linux)
SET(CMAKE_C_COMPILER /home/yqw/MetaRTC/BC/stbgcc-6.3-1.1/bin/arm-linux-gcc)
SET(CMAKE_CXX_COMPILER /home/yqw/MetaRTC/BC/stbgcc-6.3-1.1/bin/arm-linux-g++)

将这两个文件放入libmetartc6
./cmake_arm.sh

srtp

./configure --prefix="/home/yqw/temp/ffmpeg-webrtc/FFmpeg-n4.3.3/metartc6/libsrtp-2-fit" --host="arm-linux" --enable-static --enable-shared CC=/home/yqw/MetaRTC/BC/stbgcc-6.3-1.1/bin/arm-linux-gcc
make -j20

RV32

export PATH=$PATH:/home/yqw/MetaRTC/RV/usr/bin

./configure --prefix="/home/yqw/temp/ffmpeg-webrtc/FFmpeg-n4.3.3/metartc6/libsrtp-2-fit" --host="arm-linux" --enable-static --enable-shared CC=arm-linux-gnueabihf-gcc

openssl

 ./config no-asm shared no-async --prefix=$(pwd)/build --cross-compile-prefix=/home/yqw/MetaRTC/BC/stbgcc-6.3-1.1/bin/arm-linux-make -j20sudo make install

add CC

./config no-asm shared no-async --prefix=$(pwd)/build --cross-compile-prefix=arm-linux- CC=gcc

RV32

export PATH=$PATH:/home/yqw/MetaRTC/RV/usr/bin

./config no-asm shared no-async --prefix=$(pwd)/build --cross-compile-prefix=arm-linux-gnueabihf-

然后把Makefile中的所有的-m64删去

在build中到.a

编译ffmpeg

./configure --cross-prefix=/home/yqw/MetaRTC/BC/stbgcc-6.3-1.1/bin/arm-linux- --enable-cross-compile --target-os=linux --cc=/home/yqw/MetaRTC/BC/stbgcc-6.3-1.1/bin/arm-linux-gcc --arch=arm --prefix=$(pwd)/build32 --disable-shared --enable-static --extra-libs='-L/home/yqw/temp/ffmpeg-webrtc/FFmpeg-n4.3.3/metartc6 -lmetartccore6 -lpthread -lsrtp2 -lssl -lcrypto -ldl'

RV32

./configure --cross-prefix=/home/yqw/MetaRTC/RV/bin/arm-linux-gnueabihf- --enable-cross-compile --target-os=linux --cc=arm-linux-gnueabihf-gcc --arch=arm --prefix=$(pwd)/build_RV32 --disable-shared --enable-static --extra-libs='-L/home/yqw/temp/ffmpeg-webrtc/FFmpeg-n4.3.3/metartc6 -lmetartccore6 -lpthread -lsrtp2 -lssl -lcrypto -ldl'

注意这里的dl和pthread是调用交叉编译工具链中的库；当写在同一个–extra-libs里时没有顺序之分，如果用两个–extra-libs，那么就有加载的顺序之分，比如crypto里要用到dl，那么dl就需要放在它的前面加载。
第二个注意点，无法把ffmepg编译成动态库，不然会报如下错误：

libmetartccore6.a(YangMetaConnection.c.o): relocation R_ARM_THM_MOVW_ABS_NC against `a local symbol' can not be used when making a shared object; recompile with -fPIC

speexdsp
./autogen.sh
./configure --prefix=“$(pwd)/build-33” --host=“arm-linux” --enable-shared --enable-static CC=arm-linux-gcc
make -j20
make install

/home/yqw/temp/ffmpeg-webrtc/FFmpeg-n4.3.3/metartc6/metartc6/include/yang_config.h
#define Yang_Enable_Dtls 1 //default:using dtls
#define Yang_Enable_Openssl 1
#define Yang_Enable_RTC_Video 0

metartc支持mips32位，支持arm64，不支持arm32位，在arm32下报下列错误，这个错误是对内存的越界操作，然后再free()，目前metartc6和7都不支持arm32。
webrtc init>>>>>>>>>>>>>>>>>>>http://192.168.100.77:1985/tc/v1/whip/?app=live&stream=livestream
[webrtc @ 0x189c3c0] webrtc_open http://192.168.100.77:1985/tc/v1/whip/?app=live&stream=livestream

srtp init success!
*** Error in `/usr/data/ffmpeg’: free(): invalid next size (fast): 0x0189cd20 ***

Program received signal SIGABRT, Aborted.
0xb6e515f6 in ?? () from /lib/libc.so.6
(gdb) bt
#0 0xb6e515f6 in ?? () from /lib/libc.so.6
#1 0xb6e5f2ac in raise () from /lib/libc.so.6
#2 0xb6e5ff9a in abort () from /lib/libc.so.6
#3 0xb6e86bba in ?? () from /lib/libc.so.6
Backtrace stopped: previous frame identical to this frame (corrupt stack?)

ffmpeg-bin
./configure --cross-prefix=/home/yqw/MetaRTC/BC/stbgcc-6.3-1.1/bin/arm-linux- --enable-cross-compile --target-os=linux --cc=arm-linux-gcc --arch=arm --prefix=$(pwd)/build32 --disable-shared --enable-static --extra-libs=‘-L/home/yqw/temp/FFMPEG_WEBRTC/2.0-ffmpeg-webrtc/FFmpeg-n4.3.3/metartc2 -lmetartccore2 -lpthread -lspeexdsp -lsrtp2 -lssl -lcrypto -ldl’