help参数,进行必要性说明:
[root@VM_0_4_centos ffmpeg-4.2.1]# ./configure --help
Usage: configure [options]
Options: [defaults in brackets after descriptions]
Help options:
--help print this message
--quiet Suppress showing informative output
--list-decoders show all available decoders
--list-encoders show all available encoders
--list-hwaccels show all available hardware accelerators
--list-demuxers show all available demuxers
--list-muxers show all available muxers
--list-parsers show all available parsers
--list-protocols show all available protocols
--list-bsfs show all available bitstream filters
--list-indevs show all available input devices
--list-outdevs show all available output devices
--list-filters show all available filters
Standard options:
--logfile=FILE log tests and output to FILE [ffbuild/config.log]
--disable-logging do not log configure debug information
--fatal-warnings fail if any configure warning is generated
我们这个已经设置了
--prefix=PREFIX install in PREFIX [/usr/local]
把我们设置的perfix 赋值到此处这里来
--bindir=DIR install binaries in DIR [PREFIX/bin]
把我们设置的perfix 赋值到此处这里来
--datadir=DIR install data files in DIR [PREFIX/share/ffmpeg]
把我们设置的perfix 赋值到此处这里来
--docdir=DIR install documentation in DIR [PREFIX/share/doc/ffmpeg]
把我们设置的perfix 赋值到此处这里来
--libdir=DIR install libs in DIR [PREFIX/lib]
--shlibdir=DIR install shared libs in DIR [LIBDIR]
把我们设置的perfix 赋值到此处这里来
--incdir=DIR install includes in DIR [PREFIX/include]
把我们设置的perfix 赋值到此处这里来
--mandir=DIR install man page in DIR [PREFIX/share/man]
--pkgconfigdir=DIR install pkg-config files in DIR [LIBDIR/pkgconfig]
--enable-rpath use rpath to allow installing libraries in paths
not part of the dynamic linker search path
use rpath when linking programs (USE WITH CARE)
--install-name-dir=DIR Darwin directory name for installed targets
Licensing options:
--enable-gpl allow use of GPL code, the resulting libs
and binaries will be under GPL [no]
--enable-version3 upgrade (L)GPL to version 3 [no]
--enable-nonfree allow use of nonfree code, the resulting libs
and binaries will be unredistributable [no]
Configuration options: disable不开启,所以还需要看后面有没有[on]
--disable-static do not build static libraries [no] 默认开启 静态库
--enable-shared build shared libraries [no] 默认不开启 动态库
--enable-small optimize for size instead of speed 可以优化库的大小,可以尝试加入进去
--disable-runtime-cpudetect disable detecting CPU capabilities at runtime (smaller binary)
--enable-gray enable full grayscale support (slower color)
--disable-swscale-alpha disable alpha channel support in swscale
--disable-all disable building components, libraries and programs
--disable-autodetect disable automatically detected external libraries [no]
Program options:
我们不需要使用程序,不需要在Windows中执行,某.exe程序,我们只需要在代码中使用 [此命令操作的是下面三项]
--disable-programs do not build command line programs
--disable-ffmpeg disable ffmpeg build
--disable-ffplay disable ffplay build
--disable-ffprobe disable ffprobe build
Documentation options:
--disable-doc do not build documentation
--disable-htmlpages do not build HTML documentation pages
--disable-manpages do not build man documentation pages
--disable-podpages do not build POD documentation pages
--disable-txtpages do not build text documentation pages
FFmpeg 是由各个模块所组成的
FFmpeg是一套可以用来记录、转换数字音频、视频,并能将其转化为流的开源计算机程序。它包括了领先的音/视频编码库libavcodec等。
libavformat:用于各种音视频封装格式的生成和解析,包括获取解码所需信息以生成解码上下文结构和读取音视频帧等功能;
libavcodec:用于各种类型声音/图像编解码;
libavutil:包含一些公共的工具函数;
libswscale:用于视频场景比例缩放、色彩映射转换;
libpostproc:用于后期效果处理;
ffmpeg:该项目提供的一个工具,可用于格式转换、解码或电视卡即时编码等;
ffsever:一个 HTTP 多媒体即时广播串流服务器;
ffplay:是一个简单的播放器,使用ffmpeg 库解析和解码,通过SDL显示;
Component options:
--disable-avdevice disable libavdevice build 可以操作我们的摄像头(但是在Android中是不支持的),视频输出等等
--disable-avcodec disable libavcodec build 包含了音视频编解码的东西,默认是开启的,肯定不能关闭掉
--disable-avformat disable libavformat build 默认开启的,音视频封装格式的生成与解析
--disable-swresample disable libswresample build 对音频进行重采样的(如果想把单声道的视频,变成双声道的视频,就需要此模块)
--disable-swscale disable libswscale build 如果对一个视频 放大 缩小 就需要此模块
--disable-postproc disable libpostproc build 后期处理的,这个模块可以关闭掉
--disable-avfilter disable libavfilter build 给视频加字幕,加水印,就需要此模块,(默认开启)
--enable-avresample enable libavresample build (deprecated) [no]
--disable-pthreads disable pthreads [autodetect]
--disable-w32threads disable Win32 threads [autodetect]
--disable-os2threads disable OS/2 threads [autodetect]
--disable-network disable network support [no]
--disable-dct disable DCT code
--disable-dwt disable DWT code
--disable-error-resilience disable error resilience code
--disable-lsp disable LSP code
--disable-lzo disable LZO decoder code
--disable-mdct disable MDCT code
--disable-rdft disable RDFT code
--disable-fft disable FFT code
--disable-faan disable floating point AAN (I)DCT code
--disable-pixelutils disable pixel utils in libavutil
Individual component options:
--disable-everything disable all components listed below
--disable-encoder=NAME disable encoder NAME
--enable-encoder=NAME enable encoder NAME
--disable-encoders disable all encoders 编码可以去关闭掉
--disable-decoder=NAME disable decoder NAME
--enable-decoder=NAME enable decoder NAME
--disable-decoders disable all decoders
--disable-hwaccel=NAME disable hwaccel NAME
--enable-hwaccel=NAME enable hwaccel NAME
--disable-hwaccels disable all hwaccels
--disable-muxer=NAME disable muxer NAME
--enable-muxer=NAME enable muxer NAME
--disable-muxers disable all muxers 混合封装(音视频等于 一段音频 一段视频 合并在一起 就是.mp4,不想这样就可以关闭)
--disable-demuxer=NAME disable demuxer NAME
--enable-demuxer=NAME enable demuxer NAME
--disable-demuxers disable all demuxers
--enable-parser=NAME enable parser NAME
--disable-parser=NAME disable parser NAME
--disable-parsers disable all parsers
--enable-bsf=NAME enable bitstream filter NAME
--disable-bsf=NAME disable bitstream filter NAME
--disable-bsfs disable all bitstream filters
--enable-protocol=NAME enable protocol NAME
--disable-protocol=NAME disable protocol NAME
--disable-protocols disable all protocols
--enable-indev=NAME enable input device NAME
--disable-indev=NAME disable input device NAME
--disable-indevs disable input devices
--enable-outdev=NAME enable output device NAME
--disable-outdev=NAME disable output device NAME
--disable-outdevs disable output devices
--disable-devices disable all devices
--enable-filter=NAME enable filter NAME
--disable-filter=NAME disable filter NAME
--disable-filters disable all filters
0.2 编译脚本:
#!/bin/bash
#NDK_ROOT 变量指向ndk目录
NDK_ROOT=/root/android-ndk-r17c
#TOOLCHAIN 变量指向ndk中的交叉编译gcc所在的目录
TOOLCHAIN=$NDK_ROOT/toolchains/arm-linux-androideabi-4.9/prebuilt/linux-x86_64
#指定android api版本
ANDROID_API=17
#此变量用于编译完成之后的库与头文件存放在哪个目录
PREFIX=./android/armeabi-v7a
#执行configure脚本,用于生成makefile
#--prefix : 安装目录
#--enable-small : 优化大小
#--disable-programs : 不编译ffmpeg程序(命令行工具),我们是需要获得静态(动态)库。
#--disable-avdevice : 关闭avdevice模块,此模块在android中无用
#--disable-encoders : 关闭所有编码器 (播放不需要编码)
#--disable-muxers : 关闭所有复用器(封装器),不需要生成mp4这样的文件,所以关闭
#--disable-filters :关闭视频滤镜
#--enable-cross-compile : 开启交叉编译
#--cross-prefix: gcc的前缀 xxx/xxx/xxx-gcc 则给xxx/xxx/xxx-
#disable-shared enable-static 不写也可以,默认就是这样的。
#--sysroot:
#--extra-cflags: 会传给gcc的参数
#--arch --target-os : 必须要给
./configure \
--prefix=$PREFIX \
--enable-small \
--disable-programs \
--disable-avdevice \
--disable-encoders \
--disable-muxers \
--disable-filters \
--enable-cross-compile \
--cross-prefix=$TOOLCHAIN/bin/arm-linux-androideabi- \
--disable-shared \
--enable-static \
--sysroot=$NDK_ROOT/platforms/android-$ANDROID_API/arch-arm \
--extra-cflags="-isysroot $NDK_ROOT/sysroot -isystem $NDK_ROOT/sysroot/usr/include/arm-linux-androideabi -D__ANDROID_API__=$ANDROID_API -U_FILE_OFFSET_BITS -DANDROID -ffunction-sections -funwind-tables -fstack-protector-strong -no-canonical-prefixes -march=armv7-a -mfloat-abi=softfp -mfpu=vfpv3-d16 -mthumb -Wa,--noexecstack -Wformat -Werror=format-security -O0 -fPIC" \
--arch=arm \
--target-os=android
#上面运行脚本生成makefile之后,使用make执行脚本
make clean
make install