編譯過程中涉及到很多ndk中的so庫和頭檔案以及交叉編譯的工具，在指令執行的時候會在ndk相應的目錄下去查找，是以我們可以使用export指令事先将這些路徑設定到環境變量，使用的時候可以很友善的找到
//NDK加入環境變量，以我的ndk存放路徑為例
export NDK=/root/renzhenming/ffmpeg/android-ndk-r14b
//ndk的platforms檔案夾中存放的是各個版本架構下的so庫和頭檔案
export PLATFORM=$NDK/platforms/android-21/arch-arm
//指定交叉編譯工具的路徑
export TOOLCHAIN=$NDK/toolchains/arm-linux-androideabi-4.9/prebuilt/linux-x86_64
//指定輸出類型,以armv7-a為例
export CPU=armv7-a
//指定so檔案編譯後的輸出路徑
export PREFIX=./android/$CPU
相關指令解析
腳本中定義了一個方法build_ffmpeg，最終它被調用兩次生成支援neon和硬解碼的so庫和不支援neon和硬解碼的so庫
configure ：是ffmpeg中已有的一個配置檔案，我們的腳本其實也就是去執行這個檔案，所有生成so的工作都在這裡進行
prefix : 指定最終生成的so的安裝目錄
target-os ： 指定目标系統，早期很多腳本在2.x上把這個指定為linux,可以，但是ffmpeg更新之後，在3.x的版本之上會導緻問題，頭檔案找不到之類的，這是一點差異
cross-prefix：指定交叉編譯的字首，在交叉編譯的情況下，比如交叉編譯使用的gcc，那麼會在gcc前加上這個字首，就是一個完整的gcc工具的路徑，可以通過這個路徑找到這個工具（/home/renzhenming/ffmpeg/android-ndk-r14b/toolchains/arm-linux-androideabi-4.9/prebuilt/linux-x86_64/bin/arm-linux-androideabi-gcc）
sysroot:指定這套系統依賴的庫和頭檔案位置，就是我們配置的PLATFORMS，交叉編譯在本系統中是找不到這些庫的，可以把這些庫看作是交叉編譯的環境。如果在編譯時指定了-sysroot就是為編譯時指定了邏輯目錄。編譯過程中需要引用的庫，頭檔案，如果要到/usr/include目錄下去找的情況下，則會在前面加上邏輯目錄。
extra-cflags：是使用$（CC）(cc中指定的編譯器)編譯C檔案的選項,給gcc提供的一系列參數，這個可配可不配。 -fPIC編譯動态連結庫的參數， -mfpu指定協處理器，-mfloat-abi=softfp軟浮點
cc : linux下cc一般是一個符号連接配接，指向gcc，一般是makefile裡面的一個名字，即宏定義，就把他當做一個已經定義好的變量，可以指定編譯器即可，ffmpeg是c語言寫的，這裡指定gcc為編譯器，g++是c++編譯器
nm：符号檢視工具，nm 指令顯示關于指定 File 中符号的資訊，檔案可以是對象檔案、可執行檔案或對象檔案庫。如果檔案沒有包含符号資訊，nm 指令報告該情況，但不把它解釋為出錯條件。 nm 指令預設情況下報告十進制符号表示法下的數字值。
enable-shared：編譯成動态庫，大概在3.4之前的ffmpeg版本，我們編譯的時候需要修改configure檔案中的一些參數，因為預設生成的so庫檔案名有問題，無法直接調用，3.4不再需要手動修改
enable-runtime-cpudetect ：開啟運作期cpu檢測，不支援的指令可以自動被替換
enable-gpl：強開源限制授權General Public License ，ffmpeg有2個協定可以選擇，預設的編譯配置是LGPL，可以不開源,但如果你編譯時加入了 --enable-gpl那麼必須以GPL釋出
,你的代碼要開源，否則不準開啟gpl，不開啟有些庫無法使用
enable-small：打出來的so更小
enable-asm:允許彙編，指令優化
支援硬解碼，打開後jni可以調用java的源碼
--enable-jni
--enable-mediacodec
解碼器
--enable-decoder=h264_mediacodec
硬體加速
--enable-hwaccel=h264_mediacodec \
完整的編譯腳本
這個腳本目前經過驗證，可以正常的進行編譯3.4版本和3.4.4版本的ffmpeg,前提是需要保證每一個配置參數的正确，一般如果編譯出現問題，大多是由于ndk的幾個路徑錯誤，NDK/PLATFORM/TOOLCHAIN這三個變量核對一下是否和你的ndk目錄一緻
#!/bin/bash
echo "進入編譯ffmpeg腳本"
NDK=/home/ren/ffmpeg/android-ndk-r14b
#5.0
PLATFORM=$NDK/platforms/android-21/arch-arm
TOOLCHAIN=$NDK/toolchains/arm-linux-androideabi-4.9/prebuilt/linux-x86_64
CPU=arm
#輸出路徑
PREFIX=./android/$CPU
function build_ffmpeg
{
echo "開始編譯ffmpeg"
./configure \
--prefix=$PREFIX \
--target-os=android \
--cross-prefix=$TOOLCHAIN/bin/arm-linux-androideabi- \
--arch=arm \
--cpu=$CPU \
--extra-libs=-lgcc \
--sysroot=$PLATFORM \
--extra-cflags="$CFLAG" \
--cc=$TOOLCHAIN/bin/arm-linux-androideabi-gcc \
--nm=$TOOLCHAIN/bin/arm-linux-androideabi-nm \
--enable-shared \
--enable-runtime-cpudetect \
--enable-gpl \
--enable-small \
--enable-cross-compile \
--disable-debug \
--disable-static \
--disable-doc \
--disable-ffmpeg \
--disable-ffplay \
--disable-ffprobe \
--disable-ffserver \
--disable-postproc \
--disable-avdevice \
--disable-symver \
--disable-stripping \
$ADD
#開啟16個線程
make -j16
make install
echo "編譯結束！"
}
###########################################################
echo "編譯支援neon和硬解碼"
CPU=armv7-a
PREFIX=./android/armv7-a-neon-hard
#-fPIC 作用于編譯階段，告訴編譯器産生與位置無關代碼(Position-Independent Code)，
#則産生的代碼中，沒有絕對位址，全部使用相對位址，故而代碼可以被
#加載器加載到記憶體的任意位置，都可以正确的執行。這正是共享庫所要
#求的，共享庫被加載時，在記憶體的位置不是固定的。
#如果不加-fPIC,則加載.so檔案的代碼段時,代碼段引用的資料對象需要重
#定位, 重定位會修改代碼段的内容,這就造成每個使用這個.so檔案代碼段
#的程序在核心裡都會生成這個.so檔案代碼段的copy.每個copy都不一樣,
#取決于 這個.so檔案代碼段和資料段記憶體映射的位置. 也就是
#不加fPIC編譯出來的so,是要再加載時根據加載到的位置再次重定位的.(因
#為它裡面的代碼并不是位置無關代碼)
#如果被多個應用程式共同使用,那麼它們必須每個程式維護一份.so的代碼
#副本了.(因為.so被每個程式加載的位置都不同,顯然這些重定位後的代碼
#也不同,當然不能共享)
#我們總是用fPIC來生成so,也從來不用fPIC來生成.a;
#-mfpu=neon 浮點協處理器指令，使用硬體浮點的時候，我們需要給編譯器傳遞一些參數，讓編譯器編譯出硬體浮點單元處理器能識别的指令。參數-mfpu就是用來指定要産生哪種硬體浮點運算指令,常用的右vfp和neon等.
#-mfloat-abi=soft使用這個參數時，其将調用軟浮點庫(softfloat lib)來持
#對浮點的運算，GCC編譯器已經有這個庫了，一般在libgcc裡面。這
#時根本不會使用任何浮點指令，而是采用常用的指令來模拟浮點運算。
#但使用的ARM晶片不支援硬浮點時，可以考慮使用這個參數。
#-mfloat-abi=softfp
#-mfloat-abi=hard
#這兩個參數都用來産生硬浮點指令，至于産生哪種類型的硬浮點指令，
#需要由-mfpu=xxx參數來指令。這兩個參數不同的地方是：
#-mfloat-abi=softfp生成的代碼采用相容軟浮點調用接口(即使用-mfloat-abi=soft時的調用接口)，
#這樣帶來的好處是：相容性和靈活性。庫可以采用-mfloat-abi=soft編
#譯，而關鍵的應用程式可以采用-mfloat-abi=softfp來編譯。特别是在庫
#由第三方釋出的情況下。
#-mfloat-abi=hard生成的代碼采用硬浮點(FPU)調用接口。這樣要求所有
#庫和應用程式必須采用這同一個參數來編譯，否則連接配接時會出現接口不
#相容錯誤。
#預設情況下，gcc在下面目錄中搜尋頭檔案：
#/usr/local/include/
#/usr/include/
#在下面目錄中搜尋庫：
#/usr/local/lib/
#/usr/lib/
CFLAG="-I$PLATFORM/usr/include -fPIC -DANDROID -mfpu=neon -mfloat-abi=softfp "
#--enable-asm程式集優化
ADD="--enable-asm \
#neon指令集，開發者可以為需要高性能的應用程式編寫NEON指令來實作相應功能
#NEON:SIMD(SingleInstructionMultipleData單指令多重資料)指令集，其針對多媒體
#和訊号處理程式具備标準化的加速能力。
--enable-neon \
#添加jni支援，那麼ffmpeg可以調用java代碼
--enable-jni \
# 硬解碼相關
--enable-mediacodec \
--enable-decoder=h264_mediacodec \
--enable-hwaccel=h264_mediacodec "
build_ffmpeg
###########################################################
echo "編譯不支援neon和硬解碼"
CPU=armv7-a
PREFIX=./android/$CPU
#VFP:(VectorFloatPoint),向量浮點運算單元，arm11（s3c6410支援
#VFPv2），Cortex-#A8（s5pv210）支援VFPv3.
#-mfpu=name（neonorvfpvx）指定FPU單元
#-mfloat-abi=name（soft、hard、softfp）：指定軟體浮點或硬體浮點或相容軟浮點調用
#接口
#如果隻指定-mfpu，那麼預設編譯不會選擇選擇硬體浮點指令集
#如果隻指定-mfloat-abi=hard或者softfp，那麼編譯會使用硬體浮點指令集
CFLAG="-I$PLATFORM/usr/include -fPIC -DANDROID -mfpu=vfp -mfloat-abi=softfp "
ADD=
build_ffmpeg
ffmpeg編譯參數解析
來自./configure --help
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
--prefix=PREFIX install in PREFIX [/usr/local]
--bindir=DIR install binaries in DIR [PREFIX/bin]
--datadir=DIR install data files in DIR [PREFIX/share/ffmpeg]
--docdir=DIR install documentation in DIR [PREFIX/share/doc/ffmpeg]
--libdir=DIR install libs in DIR [PREFIX/lib]
--shlibdir=DIR install shared libs in DIR [LIBDIR]
--incdir=DIR install includes in DIR [PREFIX/include]
--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-static do not build static libraries [no]
--enable-shared build shared libraries [no]
--enable-small optimize for size instead of speed
--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:
--disable-programs do not build command line programs
--disable-ffmpeg disable ffmpeg build
--disable-ffplay disable ffplay build
--disable-ffprobe disable ffprobe build
--disable-ffserver disable ffserver 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
Component options:
--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 libavfilter build
--enable-avresample enable libavresample build [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
--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
--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
--disable-v4l2_m2m disable V4L2 mem2mem code [autodetect]
External library support:
Using any of the following switches will allow FFmpeg to link to the
corresponding external library. All the components depending on that library
will become enabled, if all their other dependencies are met and they are not
explicitly disabled. E.g. --enable-libwavpack will enable linking to
libwavpack and allow the libwavpack encoder to be built, unless it is
specifically disabled with --disable-encoder=libwavpack.
Note that only the system libraries are auto-detected. All the other external
libraries must be explicitly enabled.
Also note that the following help text describes the purpose of the libraries
themselves, not all their features will necessarily be usable by FFmpeg.
--disable-alsa disable ALSA support [autodetect]
--disable-appkit disable Apple AppKit framework [autodetect]
--disable-avfoundation disable Apple AVFoundation framework [autodetect]
--enable-avisynth enable reading of AviSynth script files [no]
--disable-bzlib disable bzlib [autodetect]
--disable-coreimage disable Apple CoreImage framework [autodetect]
--enable-chromaprint enable audio fingerprinting with chromaprint [no]
--enable-frei0r enable frei0r video filtering [no]
--enable-gcrypt enable gcrypt, needed for rtmp(t)e support
if openssl, librtmp or gmp is not used [no]
--enable-gmp enable gmp, needed for rtmp(t)e support
if openssl or librtmp is not used [no]
--enable-gnutls enable gnutls, needed for https support
if openssl is not used [no]
--disable-iconv disable iconv [autodetect]
--disable-jack disable libjack support [autodetect]
--enable-jni enable JNI support [no]
--enable-ladspa enable LADSPA audio filtering [no]
--enable-libass enable libass subtitles rendering,
needed for subtitles and ass filter [no]
--enable-libbluray enable BluRay reading using libbluray [no]
--enable-libbs2b enable bs2b DSP library [no]
--enable-libcaca enable textual display using libcaca [no]
--enable-libcelt enable CELT decoding via libcelt [no]
--enable-libcdio enable audio CD grabbing with libcdio [no]
--enable-libdc1394 enable IIDC-1394 grabbing using libdc1394
and libraw1394 [no]
--enable-libfdk-aac enable AAC de/encoding via libfdk-aac [no]
--enable-libflite enable flite (voice synthesis) support via libflite [no]
--enable-libfontconfig enable libfontconfig, useful for drawtext filter [no]
--enable-libfreetype enable libfreetype, needed for drawtext filter [no]
--enable-libfribidi enable libfribidi, improves drawtext filter [no]
--enable-libgme enable Game Music Emu via libgme [no]
--enable-libgsm enable GSM de/encoding via libgsm [no]
--enable-libiec61883 enable iec61883 via libiec61883 [no]
--enable-libilbc enable iLBC de/encoding via libilbc [no]
--enable-libkvazaar enable HEVC encoding via libkvazaar [no]
--enable-libmodplug enable ModPlug via libmodplug [no]
--enable-libmp3lame enable MP3 encoding via libmp3lame [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-libopenh264 enable H.264 encoding via OpenH264 [no]
--enable-libopenjpeg enable JPEG 2000 de/encoding via OpenJPEG [no]
--enable-libopenmpt enable decoding tracked files via libopenmpt [no]
--enable-libopus enable Opus de/encoding via libopus [no]
--enable-libpulse enable Pulseaudio input via libpulse [no]
--enable-librsvg enable SVG rasterization via librsvg [no]
--enable-librubberband enable rubberband needed for rubberband filter [no]
--enable-librtmp enable RTMP[E] support via librtmp [no]
--enable-libshine enable fixed-point MP3 encoding via libshine [no]
--enable-libsmbclient enable Samba protocol via libsmbclient [no]
--enable-libsnappy enable Snappy compression, needed for hap encoding [no]
--enable-libsoxr enable Include libsoxr resampling [no]
--enable-libspeex enable Speex de/encoding via libspeex [no]
--enable-libssh enable SFTP protocol via libssh [no]
--enable-libtesseract enable Tesseract, needed for ocr filter [no]
--enable-libtheora enable Theora encoding via libtheora [no]
--enable-libtwolame enable MP2 encoding via libtwolame [no]
--enable-libv4l2 enable libv4l2/v4l-utils [no]
--enable-libvidstab enable video stabilization using vid.stab [no]
--enable-libvmaf enable vmaf filter via libvmaf [no]
--enable-libvo-amrwbenc enable AMR-WB encoding via libvo-amrwbenc [no]
--enable-libvorbis enable Vorbis en/decoding via libvorbis,
native implementation exists [no]
--enable-libvpx enable VP8 and VP9 de/encoding via libvpx [no]
--enable-libwavpack enable wavpack encoding via libwavpack [no]
--enable-libwebp enable WebP encoding via libwebp [no]
--enable-libx264 enable H.264 encoding via x264 [no]
--enable-libx265 enable HEVC encoding via x265 [no]
--enable-libxavs enable AVS encoding via xavs [no]
--enable-libxcb enable X11 grabbing using XCB [autodetect]
--enable-libxcb-shm enable X11 grabbing shm communication [autodetect]
--enable-libxcb-xfixes enable X11 grabbing mouse rendering [autodetect]
--enable-libxcb-shape enable X11 grabbing shape rendering [autodetect]
--enable-libxvid enable Xvid encoding via xvidcore,
native MPEG-4/Xvid encoder exists [no]
--enable-libxml2 enable XML parsing using the C library libxml2 [no]
--enable-libzimg enable z.lib, needed for zscale filter [no]
--enable-libzmq enable message passing via libzmq [no]
--enable-libzvbi enable teletext support via libzvbi [no]
--disable-lzma disable lzma [autodetect]
--enable-decklink enable Blackmagic DeckLink I/O support [no]
--enable-libndi_newtek enable Newteck NDI I/O support [no]
--enable-mediacodec enable Android MediaCodec support [no]
--enable-libmysofa enable libmysofa, needed for sofalizer filter [no]
--enable-openal enable OpenAL 1.1 capture support [no]
--enable-opencl enable OpenCL code
--enable-opengl enable OpenGL rendering [no]
--enable-openssl enable openssl, needed for https support
if gnutls is not used [no]
--disable-sndio disable sndio support [autodetect]
--disable-schannel disable SChannel SSP, needed for TLS support on
Windows if openssl and gnutls are not used [autodetect]
--disable-sdl2 disable sdl2 [autodetect]
--disable-securetransport disable Secure Transport, needed for TLS support
on OSX if openssl and gnutls are not used [autodetect]
--disable-xlib disable xlib [autodetect]
--disable-zlib disable zlib [autodetect]
The following libraries provide various hardware acceleration features:
--disable-audiotoolbox disable Apple AudioToolbox code [autodetect]
--disable-cuda disable dynamically linked Nvidia CUDA code [autodetect]
--enable-cuda-sdk enable CUDA features that require the CUDA SDK [no]
--disable-cuvid disable Nvidia CUVID support [autodetect]
--disable-d3d11va disable Microsoft Direct3D 11 video acceleration code [autodetect]
--disable-dxva2 disable Microsoft DirectX 9 video acceleration code [autodetect]
--enable-libdrm enable DRM code (Linux) [no]
--enable-libmfx enable Intel MediaSDK (AKA Quick Sync Video) code via libmfx [no]
--enable-libnpp enable Nvidia Performance Primitives-based code [no]
--enable-mmal enable Broadcom Multi-Media Abstraction Layer (Raspberry Pi) via MMAL [no]
--disable-nvenc disable Nvidia video encoding code [autodetect]
--enable-omx enable OpenMAX IL code [no]
--enable-omx-rpi enable OpenMAX IL code for Raspberry Pi [no]
--enable-rkmpp enable Rockchip Media Process Platform code [no]
--disable-vaapi disable Video Acceleration API (mainly Unix/Intel) code [autodetect]
--disable-vda disable Apple Video Decode Acceleration code [autodetect]
--disable-vdpau disable Nvidia Video Decode and Presentation API for Unix code [autodetect]
--disable-videotoolbox disable VideoToolbox code [autodetect]
Toolchain options:
--arch=ARCH select architecture []
--cpu=CPU select the minimum required CPU (affects
instruction selection, may crash on older CPUs)
--cross-prefix=PREFIX use PREFIX for compilation tools []
--progs-suffix=SUFFIX program name suffix []
--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
--target-samples=DIR path to samples directory on target
--tempprefix=PATH force fixed dir/prefix instead of mktemp for checks
--toolchain=NAME set tool defaults according to NAME
--nm=NM use nm tool NM [nm -g]
--ar=AR use archive tool AR [ar]
--as=AS use assembler AS []
--ln_s=LN_S use symbolic link tool LN_S [ln -s -f]
--strip=STRIP use strip tool STRIP [strip]
--windres=WINDRES use windows resource compiler WINDRES [windres]
--x86asmexe=EXE use nasm-compatible assembler EXE [nasm]
--cc=CC use C compiler CC [gcc]
--cxx=CXX use C compiler CXX [g++]
--objcc=OCC use ObjC compiler OCC [gcc]
--dep-cc=DEPCC use dependency generator DEPCC [gcc]
--nvcc=NVCC use Nvidia CUDA compiler NVCC [nvcc]
--ld=LD use linker LD []
--pkg-config=PKGCONFIG use pkg-config tool PKGCONFIG [pkg-config]
--pkg-config-flags=FLAGS pass additional flags to pkgconf []
--ranlib=RANLIB use ranlib RANLIB [ranlib]
--doxygen=DOXYGEN use DOXYGEN to generate API doc [doxygen]
--host-cc=HOSTCC use host C compiler HOSTCC
--host-cflags=HCFLAGS use HCFLAGS when compiling for host
--host-cppflags=HCPPFLAGS use HCPPFLAGS when compiling for host
--host-ld=HOSTLD use host linker HOSTLD
--host-ldflags=HLDFLAGS use HLDFLAGS when linking for host
--host-libs=HLIBS use libs HLIBS when linking for host
--host-os=OS compiler host OS []
--extra-cflags=ECFLAGS add ECFLAGS to CFLAGS []
--extra-cxxflags=ECFLAGS add ECFLAGS to CXXFLAGS []
--extra-objcflags=FLAGS add FLAGS to OBJCFLAGS []
--extra-ldflags=ELDFLAGS add ELDFLAGS to LDFLAGS []
--extra-ldexeflags=ELDFLAGS add ELDFLAGS to LDEXEFLAGS []
--extra-ldlibflags=ELDFLAGS add ELDFLAGS to LDLIBFLAGS []
--extra-libs=ELIBS add ELIBS []
--extra-version=STRING version string suffix []
--optflags=OPTFLAGS override optimization-related compiler flags
--nvccflags=NVCCFLAGS override nvcc flags [-gencode arch=compute_30,code=sm_30 -O2]
--build-suffix=SUFFIX library name suffix []
--enable-pic build position-independent code
--enable-thumb compile for Thumb instruction set
--enable-lto use link-time optimization
--env="ENV=override" override the environment variables
Advanced options (experts only):
--malloc-prefix=PREFIX prefix malloc and related names with PREFIX
--custom-allocator=NAME use a supported custom allocator
--disable-symver disable symbol versioning
--enable-hardcoded-tables use hardcoded tables instead of runtime generation
--disable-safe-bitstream-reader
disable buffer boundary checking in bitreaders
(faster, but may crash)
--sws-max-filter-size=N the max filter size swscale uses [256]
Optimization options (experts only):
--disable-asm disable all assembly optimizations
--disable-altivec disable AltiVec optimizations
--disable-vsx disable VSX optimizations
--disable-power8 disable POWER8 optimizations
--disable-amd3dnow disable 3DNow! optimizations
--disable-amd3dnowext disable 3DNow! extended optimizations
--disable-mmx disable MMX optimizations
--disable-mmxext disable MMXEXT optimizations
--disable-sse disable SSE optimizations
--disable-sse2 disable SSE2 optimizations
--disable-sse3 disable SSE3 optimizations
--disable-ssse3 disable SSSE3 optimizations
--disable-sse4 disable SSE4 optimizations
--disable-sse42 disable SSE4.2 optimizations
--disable-avx disable AVX optimizations
--disable-xop disable XOP optimizations
--disable-fma3 disable FMA3 optimizations
--disable-fma4 disable FMA4 optimizations
--disable-avx2 disable AVX2 optimizations
--disable-aesni disable AESNI optimizations
--disable-armv5te disable armv5te optimizations
--disable-armv6 disable armv6 optimizations
--disable-armv6t2 disable armv6t2 optimizations
--disable-vfp disable VFP optimizations
--disable-neon disable NEON optimizations
--disable-inline-asm disable use of inline assembly
--disable-x86asm disable use of standalone x86 assembly
--disable-mipsdsp disable MIPS DSP ASE R1 optimizations
--disable-mipsdspr2 disable MIPS DSP ASE R2 optimizations
--disable-msa disable MSA optimizations
--disable-mipsfpu disable floating point MIPS optimizations
--disable-mmi disable Loongson SIMD optimizations
--disable-fast-unaligned consider unaligned accesses slow
Developer options (useful when working on FFmpeg itself):
--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
--assert-level=level 0(default), 1 or 2, amount of assertion testing,
2 causes a slowdown at runtime.
--enable-memory-poisoning fill heap uninitialized allocated space with arbitrary data
--valgrind=VALGRIND run "make fate" tests through valgrind to detect memory
leaks and errors, using the specified valgrind binary.
Cannot be combined with --target-exec
--enable-ftrapv Trap arithmetic overflows
--samples=PATH location of test samples for FATE, if not set use
$FATE_SAMPLES at make invocation time.
--enable-neon-clobber-test check NEON registers for clobbering (should be
used only for debugging purposes)
--enable-xmm-clobber-test check XMM registers for clobbering (Win64-only;
should be used only for debugging purposes)
--enable-random randomly enable/disable components
--disable-random
--enable-random=LIST randomly enable/disable specific components or
--disable-random=LIST component groups. LIST is a comma-separated list
of NAME[:PROB] entries where NAME is a component
(group) and PROB the probability associated with
NAME (default 0.5).
--random-seed=VALUE seed value for --enable/disable-random
--disable-valgrind-backtrace do not print a backtrace under Valgrind
(only applies to --disable-optimizations builds)
--enable-osfuzz Enable building fuzzer tool
--libfuzzer=PATH path to libfuzzer
--ignore-tests=TESTS comma-separated list (without "fate-" prefix
in the name) of tests whose result is ignored
--enable-linux-perf enable Linux Performance Monitor API
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