参考:http://www.360doc.com/content/11/0118/16/5532256_87407443.shtml http://abitno.me/compile-ffmpeg-android-ndk折腾了两天,终于在windows上把ffmpeg编译出来了。讲讲编译的步骤:1. 安装cygwin 必须是1.7或者更新的版本 安装cygwin的时候,选择安装gcc和make,目的是为了提供编译环境, make的版本至少是3.812.安装ndk
2.1 下载ndk-r4b-windows,并将其放到cygwin的/home/Administator目录 设置环境变量 将/etc/skel/目录的 .bash_profile .bashrc .inputrc拷贝到/home/administrator目录, 编辑/home/administrator目录的 .bashrc文件,在后面增加两行: NDK_ROOT=~/android-ndk-r4b-windows/android-ndk-r4b/ export NDK_ROOT ~的实际目录是cygwin的/home/Administrator目录 3.下载ffmpeg 版本是0.6.1 在android-ndk-r4b/samples目录,创建文件夹FFMPEG,在ffmpeg目录创建jni目录, 将ffmpeg解压并将全部源码拷贝到jni目录 ffmpeg源码的路径变成: ~/android-ndk-r4b-windows/android-ndk-r4b/samples/FFMPEG/jni/ffmpeg 4.编译准备 cd到ffmpeg目录,执行dos2unix configure,转换文件格式 在ffmpeg源码目录新建config.sh,并转换成 unix格式, 内容如下: #!/bin/bash PREBUILT=/home/Administrator/android-ndk-r4b-windows/android-ndk-r4b/build/prebuilt/windows/arm-eabi-4.4.0 PLATFORM=/home/Administrator/android-ndk-r4b-windows/android-ndk-r4b/build/platforms/android-8/arch-arm ./configure --target-os=linux --arch=arm --enable-version3 --enable-gpl --enable-nonfree --disable-stripping --disable-ffmpeg --disable-ffplay --disable-ffserver --disable-ffprobe --disable-encoders --disable-muxers --disable-devices --disable-protocols --enable-protocol=file --enable-avfilter --disable-network --disable-mpegaudio-hp --disable-avdevice --enable-cross-compile --cc=$PREBUILT/bin/arm-eabi-gcc --cross-prefix=$PREBUILT/bin/arm-eabi- --nm=$PREBUILT/bin/arm-eabi-nm --extra-cflags="-fPIC -DANDROID" --disable-asm --enable-neon --enable-armv5te --extra-ldflags="-Wl,-T,$PREBUILT/arm-eabi/lib/ldscripts/armelf.x -Wl,-rpath-link=$PLATFORM/usr/lib -L$PLATFORM/usr/lib -nostdlib $PREBUILT/lib/gcc/arm-eabi/4.4.0/crtbegin.o $PREBUILT/lib/gcc/arm-eabi/4.4.0/crtend.o -lc -lm -ldl" 执行: chmod +x config.sh && ./config.sh 输出 :creating config.mak and config.h... 执行成功 修改生成的config.h,将其中的 #define restrict restrict 改成 #define restrict 转换文件格式 编辑libavutil/libm.h,将其中的所有static方法删除 转换文件格式 修改libavcodec,libavfilter,libavformat,libavutil,libpostproc和libswscale目录的MakeFile文件, 将以下内容删除: include $( SUBDIR ) ../config.mak include $ (SUBDIR) .. / subdir.mak 修改之后转换文件格式 在ffmpeg源码目录新建av.mk文件 内容如下: # LOCAL_PATH is one of libavutil, libavcodec, libavformat, or libswscale #include $(LOCAL_PATH)/../config-$(TARGET_ARCH).makinclude $(LOCAL_PATH)/../config.makOBJS :=OBJS-yes :=MMX-OBJS-yes :=include $(LOCAL_PATH)/Makefile# collect objectsOBJS-$(HAVE_MMX) += $(MMX-OBJS-yes)OBJS += $(OBJS-yes)FFNAME := lib$(NAME)FFLIBS := $(foreach,NAME,$(FFLIBS),lib$(NAME))FFCFLAGS = -DHAVE_AV_CONFIG_H -Wno-sign-compare -Wno-switch -Wno-pointer-signFFCFLAGS += -DTARGET_CONFIG=/"config-$(TARGET_ARCH).h/"ALL_S_FILES := $(wildcard $(LOCAL_PATH)/$(TARGET_ARCH)/*.S)ALL_S_FILES := $(addprefix $(TARGET_ARCH)/, $(notdir $(ALL_S_FILES)))ifneq ($(ALL_S_FILES),)ALL_S_OBJS := $(patsubst %.S,%.o,$(ALL_S_FILES))C_OBJS := $(filter-out $(ALL_S_OBJS),$(OBJS))S_OBJS := $(filter $(ALL_S_OBJS),$(OBJS))elseC_OBJS := $(OBJS)S_OBJS :=endifC_FILES := $(patsubst %.o,%.c,$(C_OBJS))S_FILES := $(patsubst %.o,%.S,$(S_OBJS))FFFILES := $(sort $(S_FILES)) $(sort $(C_FILES)) 创建一系列Android.mk文件 在jni目录,创建Android.mk,内容如下: include $(all-subdir-makefiles) 在ffmpeg目录,创建Android.mk,文件如下: LOCAL_PATH := $(call my-dir) include $(CLEAR_VARS) LOCAL_STATIC_LIBRARIES := libavformat libavcodec libavutil libpostproc libswscale LOCAL_MODULE := ffmpeg include $(BUILD_SHARED_LIBRARY) include $(call all-makefiles-under,$(LOCAL_PATH)) 在libavformat/目录,创建Android.mk,文件如下: LOCAL_PATH := $(call my-dir) include $(CLEAR_VARS) include $(LOCAL_PATH)/../av.mk LOCAL_SRC_FILES := $(FFFILES) LOCAL_C_INCLUDES := / $(LOCAL_PATH) / $(LOCAL_PATH)/.. LOCAL_CFLAGS += $(FFCFLAGS) LOCAL_CFLAGS += -include "string.h" -Dipv6mr_interface=ipv6mr_ifindex LOCAL_LDLIBS := -lz LOCAL_STATIC_LIBRARIES := $(FFLIBS) LOCAL_MODULE := $(FFNAME) include $(BUILD_STATIC_LIBRARY) 在libavcodec/目录,创建Android.mk,文件如下: LOCAL_PATH := $(call my-dir) include $(CLEAR_VARS) include $(LOCAL_PATH)/../av.mk LOCAL_SRC_FILES := $(FFFILES) LOCAL_C_INCLUDES := / $(LOCAL_PATH) / $(LOCAL_PATH)/.. LOCAL_CFLAGS += $(FFCFLAGS) LOCAL_LDLIBS := -lz LOCAL_STATIC_LIBRARIES := $(FFLIBS) LOCAL_MODULE := $(FFNAME) include $(BUILD_STATIC_LIBRARY) 在libavfilter、libavutil、libpostproc和libswscale目录,创建Android.mk,文件如下: LOCAL_PATH := $(call my-dir) include $(CLEAR_VARS) include $(LOCAL_PATH)/../av.mk LOCAL_SRC_FILES := $(FFFILES) LOCAL_C_INCLUDES := / $(LOCAL_PATH) / $(LOCAL_PATH)/.. LOCAL_CFLAGS += $(FFCFLAGS) LOCAL_STATIC_LIBRARIES := $(FFLIBS) LOCAL_MODULE := $(FFNAME) include $(BUILD_STATIC_LIBRARY) 5.进行编译 执行: ndk-build NDK_PROJECT_PATH=$NDK_ROOT/samples/FFMPEG 编译成功,在生成的libs目录看到.a和.so文件 6.可能出现的错误 6.1 执行config.sh时,出现错误: Unknown option "--target-os=linux". See ./configure --help for available options. 解决办法:ffmpeg的版本不支持,换成0.6.1即可 6.2 执行config.sh是,出现错误: ./config.sh: line 8: --enable-nonfree: command not found ./config.sh: line 9: --disable-ffprobe: command not found ......... 解决办法:config.sh中的configure命令,后面跟的参数有换行符,导致系统认为 参数是新的命令行。将换行符删除即可 7.其他问题 编辑的文件,都要转换成unix文件格式。 在unix文件格式中, '/' 可以代表空格。