最近想做android平臺的視頻擴展，跟大家一樣選擇了ffmpeg.之前在同事的幫助下編譯過vlc，這個視頻工具編譯比較簡便，成功很高，可以播放一般的格式視頻，但是總歸是別人的。想自己從基本着手。
ps: vlc下載編譯方法http://www.tidroid.com/article_110.html
在網上查了一些博客啊論壇，編譯ffmpeg的文章大相徑庭，除了作者比較nb外，照着別人的編譯，沒有幾個成功了的。我覺得主要原因還是對 bash shell 命令不瞭解的原因。爲什麼要那麼寫，大家其實心裏都想知道，苦於無從下手，因爲初次接觸。我也是初次接觸，嘗試了AbitNo，等等幾個牛人編譯的congfig.sh 和 Android.mk文件都失敗了。遇到問題不能這麼就放棄，雖然也是初次接觸，但是別人能做到我也一定能成功。
下面一行一行的解釋congfig.sh文件中的命令：
#!/bin/sh 首先申明瞭這個一個 shell 命令文件，可以在終端執行。
#這兩行主要是對變量賦值，以便下面引用，暫時可以不管
PREBUILT=$ANDROID_NDK/toolchains/arm-linux-androideabi-4.4.3/prebuilt/*-x86
PLATFORM=$ANDROID_NDK/platforms/android-14/arch-arm
重要的部分開始了：
./configure --target-os=linux \ --arch=arm \ --enable-version3 \ --enable-gpl \ --enable-nonfree \ --disable-doc \
--disable-stripping \ --disable-ffmpeg \ --disable-ffplay \ 等等……
這是什麼，爲什麼寫這麼多，有什麼用。
這個configure是ffmpeg官方寫一個shell文件，文件就在ffmpeg根目錄下，用gedit打開看了一下，很多bash shell命令以及方法，作爲初學者這麼去讀肯定費勁。可以在終端 進入到ffmpeg目錄下執行 ./configure --help 如果提示沒有權限的先執行chmod a+x configure .可以看到如下提示信息：
Usage: configure [options]
Options: [defaults in brackets after descriptions]
Standard options:
--help print this message
--logfile=FILE log tests and output to FILE [config.log]
--disable-logging do not log configure debug information
--prefix=PREFIX install in PREFIX []
--bindir=DIR install binaries in DIR [PREFIX/bin]
--datadir=DIR install data files in DIR [PREFIX/share/ffmpeg]
--libdir=DIR install libs in DIR [PREFIX/lib]
--shlibdir=DIR install shared libs in DIR [PREFIX/lib]
--incdir=DIR install includes in DIR [PREFIX/include]
--mandir=DIR install man page in DIR [PREFIX/share/man]
Configuration options:
--disable-static do not build static libraries [no]
--enable-shared build shared libraries [no]
--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]
--disable-doc do not build documentation
--disable-ffmpeg disable ffmpeg build
--enable-avconv enable avconv build
--disable-ffplay disable ffplay build
--disable-ffprobe disable ffprobe build
--disable-ffserver disable ffserver build
--disable-avdevice disable libavdevice build
--disable-avcodec disable libavcodec build
--disable-avformat disable libavformat build
--disable-swresample disable libswresample build
--disable-swscale disable libswscale build
--disable-postproc disable libpostproc build
--disable-avfilter disable video filter support [no]
--disable-pthreads disable pthreads [auto]
--disable-w32threads disable Win32 threads [auto]
--disable-os2threads disable OS/2 threads [auto]
--enable-x11grab enable X11 grabbing [no]
--disable-network disable network support [no]
--enable-gray enable full grayscale support (slower color)
--disable-swscale-alpha disable alpha channel support in swscale
--disable-fastdiv disable table-based division
--enable-small optimize for size instead of speed
--disable-aandct disable AAN DCT code
--disable-dct disable DCT code
--disable-fft disable FFT code
--disable-golomb disable Golomb code
--disable-huffman disable Huffman code
--disable-lpc disable LPC code
--disable-mdct disable MDCT code
--disable-rdft disable RDFT code
--enable-vaapi enable VAAPI code [autodetect]
--enable-vda enable VDA code [autodetect]
--enable-vdpau enable VDPAU code [autodetect]
--disable-dxva2 disable DXVA2 code
--disable-vda disable VDA code
--enable-runtime-cpudetect detect cpu capabilities at runtime (bigger binary)
--enable-hardcoded-tables use hardcoded tables instead of runtime generation
--disable-safe-bitstream-reader
disable buffer boundary checking in bitreaders
(faster, but may crash)
--enable-memalign-hack emulate memalign, interferes with memory debuggers
--disable-everything disable all components listed below
--disable-encoder=NAME disable encoder NAME
--enable-encoder=NAME enable encoder NAME
--disable-encoders disable all encoders
--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
--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
--disable-indev=NAME disable input device NAME
--disable-outdev=NAME disable output device NAME
--disable-indevs disable input devices
--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
--list-decoders show all available decoders
--list-encoders show all available encoders
--list-hwaccels show all available hardware accelerators
--list-muxers show all available muxers
--list-demuxers show all available demuxers
--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
External library support:
--enable-avisynth enable reading of AVISynth script files [no]
--enable-bzlib enable bzlib [autodetect]
--enable-frei0r enable frei0r video filtering
--enable-gnutls enable gnutls [no]
--enable-libaacplus enable AAC+ encoding via libaacplus [no]
--enable-libass enable libass subtitles rendering [no]
--enable-libcelt enable CELT decoding via libcelt [no]
--enable-libopencore-amrnb enable AMR-NB de/encoding via libopencore-amrnb [no]
--enable-libopencore-amrwb enable AMR-WB decoding via libopencore-amrwb [no]
--enable-libopencv enable video filtering via libopencv [no]
--enable-libcdio enable audio CD grabbing with libcdio
--enable-libdc1394 enable IIDC-1394 grabbing using libdc1394
and libraw1394 [no]
--enable-libdirac enable Dirac support via libdirac [no]
--enable-libfaac enable FAAC support via libfaac [no]
--enable-libfreetype enable libfreetype [no]
--enable-libgsm enable GSM support via libgsm [no]
--enable-libmodplug enable ModPlug via libmodplug [no]
--enable-libmp3lame enable MP3 encoding via libmp3lame [no]
--enable-libnut enable NUT (de)muxing via libnut,
native (de)muxer exists [no]
--enable-libopenjpeg enable JPEG 2000 encoding/decoding via OpenJPEG [no]
--enable-libpulse enable Pulseaudio input via libpulse [no]
--enable-librtmp enable RTMP[E] support via librtmp [no]
--enable-libschroedinger enable Dirac support via libschroedinger [no]
--enable-libspeex enable Speex support via libspeex [no]
--enable-libstagefright-h264 enable H.264 decoding via libstagefright [no]
--enable-libtheora enable Theora encoding via libtheora [no]
--enable-libutvideo enable Ut Video decoding via libutvideo [no]
--enable-libv4l2 enable libv4l2/v4l-utils [no]
--enable-libvo-aacenc enable AAC encoding via libvo-aacenc [no]
--enable-libvo-amrwbenc enable AMR-WB encoding via libvo-amrwbenc [no]
--enable-libvorbis enable Vorbis encoding via libvorbis,
native implementation exists [no]
--enable-libvpx enable VP8 support via libvpx [no]
--enable-libx264 enable H.264 encoding via x264 [no]
--enable-libxavs enable AVS encoding via xavs [no]
--enable-libxvid enable Xvid encoding via xvidcore,
native MPEG-4/Xvid encoder exists [no]
--enable-openal enable OpenAL 1.1 capture support [no]
--enable-mlib enable Sun medialib [no]
--enable-openssl enable openssl [no]
--enable-zlib enable zlib [autodetect]
Advanced options (experts only):
--cross-prefix=PREFIX use PREFIX for compilation tools []
--enable-cross-compile assume a cross-compiler is used
--sysroot=PATH root of cross-build tree
--sysinclude=PATH location of cross-build system headers
--target-os=OS compiler targets OS []
--target-exec=CMD command to run executables on target
--target-path=DIR path to view of build directory on target
--nm=NM use nm tool
--ar=AR use archive tool AR [ar]
--as=AS use assembler AS []
--cc=CC use C compiler CC [gcc]
--cxx=CXX use C compiler CXX [g++]
--ld=LD use linker LD
--host-cc=HOSTCC use host C compiler HOSTCC
--host-cflags=HCFLAGS use HCFLAGS when compiling for host
--host-ldflags=HLDFLAGS use HLDFLAGS when linking for host
--host-libs=HLIBS use libs HLIBS when linking for host
--extra-cflags=ECFLAGS add ECFLAGS to CFLAGS []
--extra-cxxflags=ECFLAGS add ECFLAGS to CXXFLAGS []
--extra-ldflags=ELDFLAGS add ELDFLAGS to LDFLAGS []
--extra-libs=ELIBS add ELIBS []
--extra-version=STRING version string suffix []
--build-suffix=SUFFIX library name suffix []
--progs-suffix=SUFFIX program name suffix []
--arch=ARCH select architecture []
--cpu=CPU select the minimum required CPU (affects
instruction selection, may crash on older CPUs)
--disable-asm disable all assembler optimizations
--disable-altivec disable AltiVec optimizations
--disable-amd3dnow disable 3DNow! optimizations
--disable-amd3dnowext disable 3DNow! extended optimizations
--disable-mmx disable MMX optimizations
--disable-mmx2 disable MMX2 optimizations
--disable-sse disable SSE optimizations
--disable-ssse3 disable SSSE3 optimizations
--disable-avx disable AVX optimizations
--disable-armv5te disable armv5te optimizations
--disable-armv6 disable armv6 optimizations
--disable-armv6t2 disable armv6t2 optimizations
--disable-armvfp disable ARM VFP optimizations
--disable-iwmmxt disable iwmmxt optimizations
--disable-mmi disable MMI optimizations
--disable-neon disable neon optimizations
--disable-vis disable VIS optimizations
--disable-yasm disable use of yasm assembler
--enable-pic build position-independent code
--malloc-prefix=PFX prefix malloc and related names with PFX
--enable-sram allow use of on-chip SRAM
--disable-symver disable symbol versioning
--optflags override optimization-related compiler flags
Developer options (useful when working on FFmpeg itself):
--enable-coverage build with test coverage instrumentation
--disable-debug disable debugging symbols
--enable-debug=LEVEL set the debug level []
--disable-optimizations disable compiler optimizations
--enable-extra-warnings enable more compiler warnings
--disable-stripping disable stripping of executables and shared libraries
--samples=PATH location of test samples for FATE, if not set use
$FATE_SAMPLES at make invocation time.
很清楚了吧，那些命令是幹嘛用的，都有說明.在使用過程中個人需要選擇相應的命令，可以不用完全的cp別人的了。
具體的一部分其他命令，大家可以查看bash shell 基礎命令，網上找一下，說明都很詳細的。
然後再是Android.mk文件，這個mk文件很長，就不帖上來了。這些文件主要是ndk-build的時候編譯的制定的c類或者引用的makefile文件，這個文件也沒具體看，等研究後再更新上來。
希望此文章能夠給像我這樣的初學者解惑，以及更深入的研究學習，增加你們編譯成功率。牛人覺得寫得有錯或太簡單，也希望能給些指導和意見，使小弟能夠步入正軌，大家共同進步。