Mac下ndk编译ffmpeg2.1.4

编译过程中，遇到各种错误，google、百度查资料查了好久，感谢各位把自己的经验分享出来。

系统环境：OS X 10.9 , NDK R8E  FFMPEG VERSION 2.1.4

1.下载ffmpeg源码，将其放在project/jni 目录下，在其根目录新建配置脚本 ，我的配置如下：

#!/bin/bash
NDK=/Users/YangL/Documents/Android/android-ndk-r8e
SYSROOT=$NDK/platforms/android-9/arch-arm/
TOOLCHAIN=$NDK/toolchains/arm-linux-androideabi-4.7/prebuilt/darwin-x86_64
function build_one
{
    ./configure \
    --target-os=darwin \
    --arch=arm \
    --enable-cross-compile \
    --cross-prefix=$CROSS_PREFIX \
    --enable-version3 \
    --enable-optimizations \
    --enable-shared \
    --disable-static \
    --disable-symver \
    --disable-programs \
    --disable-doc \
    --disable-avdevice \
    --disable-postproc \
    --disable-encoders \
    --disable-muxers \
    --enable-muxer=mp4 \
    --disable-devices \
    --disable-demuxer=sbg \
    --disable-demuxer=dts \
    --disable-parser=dca \
    --disable-decoder=dca \
    --disable-decoder=svq3 \
    --disable-debug \
    --enable-network \
    --arch=arm \
--enable-version3 \
--enable-gpl \
--enable-nonfree \
--disable-stripping \
--disable-ffmpeg \
--disable-ffplay \
--disable-ffserver \
--disable-ffprobe \
--disable-encoders \
--disable-muxers \
--disable-devices \
--disable-protocols \
--enable-protocol=file \
--enable-avfilter \
--disable-network \
--disable-avdevice \
--enable-cross-compile \
--extra-cflags="-fPIC -DANDROID" \
--disable-asm \
--enable-neon \
--enable-armv5te \
}
CPU=arm
PREFIX=$(pwd)/android/$CPU
ADDI_CFLAGS="-marm"  
build_one

注意相应路径。

2.脚本执行成功后，将根目录下 config.h中的 #define avrestrict avrestrict 改为 #define avrestrict, 之所以这样做是因为Android的gcc不认识avrestrict。

3.将/libavutil/libm.h 中的static函数 全部注释或者删掉。

4.在ffmpeg根目录下建立av.mk,内容如下：

1. # LOCAL_PATH is one of libavutil, libavcodec, libavformat, or libswscale
   
2. include $(LOCAL_PATH)/../config.mak
   
3. OBJS :=
   
4. OBJS-yes :=
   
5. MMX-OBJS-yes :=
   
6. include $(LOCAL_PATH)/Makefile
   
7. # collect objects
   
8. OBJS-$(HAVE_MMX) += $(MMX-OBJS-yes)
   
9. OBJS += $(OBJS-yes)
   
10. FFNAME := lib$(NAME)
    
11. FFLIBS := $(foreach,NAME,$(FFLIBS),lib$(NAME))
    
12. FFCFLAGS  = -DHAVE_AV_CONFIG_H -Wno-sign-compare -Wno-switch -Wno-pointer-sign
    
13. FFCFLAGS += -DTARGET_CONFIG=\"config-$(TARGET_ARCH).h\"
    
14. ALL_S_FILES := $(wildcard $(LOCAL_PATH)/$(TARGET_ARCH)/*.S)
    
15. ALL_S_FILES := $(addprefix $(TARGET_ARCH)/, $(notdir $(ALL_S_FILES)))
    
16. ifneq ($(ALL_S_FILES),)
    
17. ALL_S_OBJS := $(patsubst %.S,%.o,$(ALL_S_FILES))
    
18. C_OBJS := $(filter-out $(ALL_S_OBJS),$(OBJS))
    
19. S_OBJS := $(filter $(ALL_S_OBJS),$(OBJS))
    
20. else
    
21. C_OBJS := $(OBJS)
    
22. S_OBJS :=
    
23. endif
    
24. C_FILES := $(patsubst %.o,%.c,$(C_OBJS))
    
25. S_FILES := $(patsubst %.o,%.S,$(S_OBJS))
    
26. FFFILES := $(sort $(S_FILES)) $(sort $(C_FILES))

5.在jni目录下建立Android.mk:

include $(all-subdir-makefiles)

6.ffmpeg目录下建立Android.mk:

LOCAL_PATH := $(call my-dir)
include $(CLEAR_VARS)
LOCAL_WHOLE_STATIC_LIBRARIES := libcpu libavformat libavcodec libavutil libswscale libswresample #libpostproc
LOCAL_ARM_MODE := arm
LOCAL_MODULE := ffmpeg
LOCAL_LDLIBS := -lz -lm -llog
include $(BUILD_SHARED_LIBRARY)
include $(call all-makefiles-under,$(LOCAL_PATH))

注意引入静态库的顺序，目标平台要指定，不然默认thumb,会导致mrs、msr等arm指令不被支持。 为此折磨了半个小时，知道的人随手一写，不知道的人，苦苦思索。

7. /ffmpeg/libavformat下建立Android.mk

1. LOCAL_PATH := $(call my-dir)
   
2. include $(CLEAR_VARS)
   
3. include $(LOCAL_PATH)/../av.mk
   
4. LOCAL_SRC_FILES := $(FFFILES)
   
5. LOCAL_C_INCLUDES :=            \
   
6.         $(LOCAL_PATH)          \
   
7.         $(LOCAL_PATH)/..
   
8. LOCAL_CFLAGS += $(FFCFLAGS)
   
9. LOCAL_CFLAGS += -include "string.h" -Dipv6mr_interface=ipv6mr_ifindex
   
10. LOCAL_LDLIBS := -lz
    
11. LOCAL_STATIC_LIBRARIES := $(FFLIBS)
    
12. LOCAL_MODULE := $(FFNAME)
    
13. include $(BUILD_STATIC_LIBRARY)

8.在/ffmpeg/libavcodec 底下新增一個Android.mk：

1. LOCAL_PATH := $(call my-dir)
   
2. include $(CLEAR_VARS)
   
3. include $(LOCAL_PATH)/../av.mk
   
4. LOCAL_SRC_FILES := $(FFFILES)
   
5. LOCAL_C_INCLUDES :=            \
   
6.         $(LOCAL_PATH)          \
   
7.         $(LOCAL_PATH)/..
   
8. LOCAL_CFLAGS += $(FFCFLAGS)
   
9. LOCAL_LDLIBS := -lz
   
10. LOCAL_STATIC_LIBRARIES := $(FFLIBS)
    
11. LOCAL_MODULE := $(FFNAME)
    
12. 
    
13. include $(BUILD_STATIC_LIBRARY)

9.在libavfilter、 libavutil、libpostproc和libswscale底下都分別新增一個Android.mk：

1. LOCAL_PATH := $(call my-dir)
   
2. include $(CLEAR_VARS)
   
3. include $(LOCAL_PATH)/../av.mk
   
4. LOCAL_SRC_FILES := $(FFFILES)
   
5. LOCAL_C_INCLUDES :=            \
   
6.         $(LOCAL_PATH)          \
   
7.         $(LOCAL_PATH)/..
   
8. LOCAL_CFLAGS += $(FFCFLAGS)
   
9. LOCAL_STATIC_LIBRARIES := $(FFLIBS)
   
10. LOCAL_MODULE := $(FFNAME)
    
11. include $(BUILD_STATIC_LIBRARY)

10.准备工作已经完成，工程目录下执行 ndk-build,编译出libavcodec.a、libavformat.a、libavutil.a、libpostproc.a、 libswscale.a和libffmpeg.so。

第一次编译耗时较长，以后增量编译就会很快。

编译中遇到的问题如下：

1.libavutil/time.h 和 系统的time.h冲突，这是个历史问题，在ffmpeg 1.1.1上即是如此。

log如下:

/jni/libavutil/parseutils.h:189: warning: 'struct tm' declared inside parameter list
/jni/libavutil/parseutils.h:189: warning: its scope is only this definition or declaration, which is probably not what you want
/jni/libavutil/parseutils.h:202: warning: 'struct tm' declared inside parameter list
/jni/libavutil/opt.c: In function 'av_find_opt':
/jni/libavutil/opt.c:49: warning: 'av_next_option' is deprecated (declared at g/jni/libavutil/opt.h:376)
/jni/libavutil/opt.c: In function 'av_opt_get':
/jni/libavutil/opt.c:665: warning: this decimal constant is unsigned only in ISO C90
/jni/libavutil/opt.c: In function 'av_opt_set_defaults':
/jni/libavutil/opt.c:1067: warning: 'av_opt_set_defaults2' is deprecated (fmpeg_streaming/jni/libavutil/opt.h:399)
utils.c
liang/ffmpeg_streaming/jni/libavutil/parseutils.c:32:
/jni/libavutil/parseutils.h:189: warning: 'struct tm' declared inside parameter list
/jni/libavutil/parseutils.h:189: warning: its scope is only this definition or declaration, which is probably not what you want
/jni/libavutil/parseutils.h:202: warning: 'struct tm' declared inside parameter list
/jni/libavutil/parseutils.c:463: warning: 'struct tm' declared inside parameter list
/jni/libavutil/parseutils.c:463: error: conflicting types for 'av_small_strptime'
/jni/libavutil/parseutils.h:189: note: previous declaration of 'av_small_strptime' was here
/jni/libavutil/parseutils.c: In function 'av_small_strptime':
/jni/libavutil/parseutils.c:485: error: dereferencing pointer to incomplete type
/jni/libavutil/parseutils.c:491: error: dereferencing pointer to incomplete type
/jni/libavutil/parseutils.c:497: error: dereferencing pointer to incomplete type
/jni/libavutil/parseutils.c:503: error: dereferencing pointer to incomplete type
/jni/libavutil/parseutils.c:509: error: dereferencing pointer to incomplete type
/jni/libavutil/parseutils.c:515: error: dereferencing pointer to incomplete type
/jni/libavutil/parseutils.c: At top level:
/jni/libavutil/parseutils.c:531: warning: 'struct tm' declared inside parameter list
/jni/libavutil/parseutils.c:531: error: conflicting types for 'av_timegm'
/jni/libavutil/parseutils.h:202: note: previous declaration of 'av_timegm' was here
/jni/libavutil/parseutils.c: In function 'av_timegm':
/jni/libavutil/parseutils.c:535: error: dereferencing pointer to incomplete type
/jni/libavutil/parseutils.c:535: error: dereferencing pointer to incomplete type
/jni/libavutil/parseutils.c:535: error: dereferencing pointer to incomplete type
/jni/libavutil/parseutils.c:545: error: dereferencing pointer to incomplete type
/jni/libavutil/parseutils.c:545: error: dereferencing pointer to incomplete type
/jni/libavutil/parseutils.c:545: error: dereferencing pointer to incomplete type
/jni/libavutil/parseutils.c: In function 'av_parse_time':
/jni/libavutil/parseutils.c:555: error: variable 'dt' has initializer but incomplete type
/jni/libavutil/parseutils.c:555: warning: excess elements in struct initializer
/jni/libavutil/parseutils.c:555: warning: (near initialization for 'dt')
/jni/libavutil/parseutils.c:555: error: storage size of 'dt' isn't known
/jni/libavutil/parseutils.c:648: error: variable 'dt2' has initializer but incomplete type
/jni/libavutil/parseutils.c:648: error: invalid type argument of 'unary *' (have 'int')
/jni/libavutil/parseutils.c:648: error: invalid type argument of 'unary *' (have 'int')
/jni/libavutil/parseutils.c:648: error: storage size of 'dt2' isn't known
g_streaming/obj/local/armeabi/objs/avutil/parseutils.o] Error 1

以上问题均是由于ffmpeg 里面 libavutil.c  底下 自带了time.h 当系统编译的时候 没有引用到 struct tm 的定义导致 ；

做了如下修改， 

1.将 libavutil/ time.h  libavutil/time.c  修改成   libavutil/ avtime.h  libavutil/avtime.c

2.将下面列出来的文件 libavutil/time.h  修改成 libavutil/avtime.h 

接着 ndk-build 即可 解决以上问题 ；

/------------------------------------------------------------------
modify :  modify time.h -> avtime.h
 cp libavutil/time.c libavutil/avtime.c
 cp libavutil/time.h libavutil/avtime.h
 vi tools/aviocat.c
 vi tools/pktdumper.c
 vi ./libavdevice/openal-dec.c
 vi ./libavdevice/bktr.c
 vi ././libavdevice/oss_audio.c
 vi ./libavdevice/v4l2-common.h
 vi ./libavdevice/alsa-audio-dec.c
 vi ./libavdevice/x11grab.c
 vi ./libavdevice/fbdev_dec.c
 vi ./libavdevice/sndio_dec.c
 vi ./libavdevice/alsa-audio-enc.c
 vi ./libavdevice/pulse_audio_enc.c
 vi ./libavdevice/jack_audio.c
 vi ./ffserver.c
 vi ./ffplay.c
 vi ././libavformat/mux.c^C
 vi ./libavformat/mux.c
 vi ./libavformat/network.c
 vi ./libavformat/hls.c
 vi ./libavformat/rtpdec.c
 vi ./libavformat/tcp.c
 vi ./libavformat/hlsproto.c
 vi ./libavformat/rtsp.c
 vi ./libavformat/rtspenc.c
 vi ././libavformat/rtmphttp.c
 vi ./libavformat/sapenc.c
 vi ./libavformat/rtspdec.c
 vi ./libavformat/udp.c
 vi ./libavformat/utils.c
 vi ./libavformat/avio.c
 vi ./libavcodec/fft-test.c
 vi ./libavcodec/motion-test.c
 vi ./libavcodec/dct-test.c
 vi ./ffmpeg.c
 vi ./libavutil/parseutils.h
 vi ./libavutil/parseutils.h
 vi ./tags
 vi ./libavfilter/setpts.c

编译错误2：make: *** No rule to make target

makefile里面的文件依赖关系有问题，导致头文件找不到。我编译时出现这个问题是因为我将编译错误1的libavutil/time.h改为/libavutil/avtime.h后没有修改相应的makefile所致。

编译错误3：android-ndk-r8d/build/core/build-binary.mk:41: *** target file 

`clean' has both : and :: entries.  Stop.

原因是libavfilter目录中的Makefile的末尾处多了 Clean 这个玩意儿 将其注释掉或者删掉就可以了

还有些编译问题，我已经在相应的Android.mk里边说明。

大家可以参考 http://blog.youkuaiyun.com/moruite/article/details/6305944