编译Android版本的libmad
1、 下载libmad源码
2、 在目录C:\cygwin\home\Administrator\android-ndk-r4b-windows\android-ndk-r4b\samples\下创建目录jni，并把libmad的源码解压到该目录下，这样mad.h的目录是：C:\cygwin\home\Administrator\android-ndk-r4b-windows\android-ndk-r4b\samples\libmad\jni\libmad-0.15.1b
3、 在jni目录下建立Android.mk内容：
include$(all-subdir-makefiles)
4、 在jni/libmad-0.15.1b目录下建立Android.mk，内容：
LOCAL_PATH := $(call my-dir)
include $(CLEAR_VARS)
LOCAL_MODULE := mad
LOCAL_ARM_MODE := arm
LOCAL_SRC_FILES := bit.c decoder.c fixed.c frame.c huffman.c layer12.clayer3.c stream.c synth.c timer.c version.c
LOCAL_CFLAGS := -DHAVE_CONFIG_H -DFPM_ARM -ffast-math -O3
include $(BUILD_SHARED_LIBRARY)
5、 启动Cygwin，到目录samples下
6、 执行：../ndk-build NDK_PROJECT_PATH=$NDK_ROOT/samples/libmad
注意：这里使用的config.h不是执行configure生成的，而是从网上down的一个，内容是：
/* config.h. Generated by configure. */
/* config.h.in. Generated from configure.ac by autoheader. */
/* Define to enable diagnostic debugging support. */
/* #undef DEBUG */
/* Define to enable experimental code. */
/* #undef EXPERIMENTAL */
/* Define to 1 if you have the <assert.h> header file. */
#define HAVE_ASSERT_H 1
/* Define to 1 if you have the <dlfcn.h> header file. */
#define HAVE_DLFCN_H 1
/* Define to 1 if you have the <errno.h> header file. */
#define HAVE_ERRNO_H 1
/* Define to 1 if you have the `fcntl' function. */
#define HAVE_FCNTL 1
/* Define to 1 if you have the <fcntl.h> header file. */
#define HAVE_FCNTL_H 1
/* Define to 1 if you have the `fork' function. */
#define HAVE_FORK 1
/* Define to 1 if you have the <inttypes.h> header file. */
#define HAVE_INTTYPES_H 1
/* Define to 1 if you have the <limits.h> header file. */
#define HAVE_LIMITS_H 1
/* Define if your MIPS CPU supports a 2-operand MADD16 instruction. */
/* #undef HAVE_MADD16_ASM */
/* Define if your MIPS CPU supports a 2-operand MADD instruction. */
/* #undef HAVE_MADD_ASM */
/* Define to 1 if you have the <memory.h> header file. */
#define HAVE_MEMORY_H 1
/* Define to 1 if you have the `pipe' function. */
#define HAVE_PIPE 1
/* Define to 1 if you have the <stdint.h> header file. */
#define HAVE_STDINT_H 1
/* Define to 1 if you have the <stdlib.h> header file. */
#define HAVE_STDLIB_H 1
/* Define to 1 if you have the <strings.h> header file. */
#define HAVE_STRINGS_H 1
/* Define to 1 if you have the <string.h> header file. */
#define HAVE_STRING_H 1
/* Define to 1 if you have the <sys/stat.h> header file. */
#define HAVE_SYS_STAT_H 1
/* Define to 1 if you have the <sys/types.h> header file. */
#define HAVE_SYS_TYPES_H 1
/* Define to 1 if you have <sys/wait.h> that is POSIX.1 compatible. */
#define HAVE_SYS_WAIT_H 1
/* Define to 1 if you have the <unistd.h> header file. */
#define HAVE_UNISTD_H 1
/* Define to 1 if you have the `waitpid' function. */
#define HAVE_WAITPID 1
/* Define to disable debugging assertions. */
/* #undef NDEBUG */
/* Define to optimize for accuracy over speed. */
/* #undef OPT_ACCURACY */
/* Define to optimize for speed over accuracy. */
#define OPT_SPEED 1
/* Define to enable a fast subband synthesis approximation optimization. */
/* #undef OPT_SSO */
/* Define to influence a strict interpretation of the ISO/IEC standards, even
if this is in opposition with best accepted practices. */
/* #undef OPT_STRICT */
/* Name of package */
#define PACKAGE "libmad"
/* Define to the address where bug reports for this package should be sent. */
#define PACKAGE_BUGREPORT "support@underbit.com"
/* Define to the full name of this package. */
#define PACKAGE_NAME "MPEG Audio Decoder"
/* Define to the full name and version of this package. */
#define PACKAGE_STRING "MPEG Audio Decoder 0.15.1b"
/* Define to the one symbol short name of this package. */
#define PACKAGE_TARNAME "libmad"
/* Define to the version of this package. */
#define PACKAGE_VERSION "0.15.1b"
/* The size of a `int', as computed by sizeof. */
#define SIZEOF_INT 4
/* The size of a `long', as computed by sizeof. */
#define SIZEOF_LONG 4
/* The size of a `long long', as computed by sizeof. */
#define SIZEOF_LONG_LONG 8
/* Define to 1 if you have the ANSI C header files. */
#define STDC_HEADERS 1
/* Version number of package */
#define VERSION "0.15.1b"
/* Define to 1 if your processor stores words with the most significant byte
first (like Motorola and SPARC, unlike Intel and VAX). */
/* #undef WORDS_BIGENDIAN */
/* Define to empty if `const' does not conform to ANSI C. */
/* #undef const */
/* Define to `__inline__' or `__inline' if that's what the C compiler
calls it, or to nothing if 'inline' is not supported under any name. */
#ifndef __cplusplus
/* #undef inline */
#endif
/* Define to `int' if <sys/types.h> does not define. */
/* #undef pid_t */
摘自：BuleRiver的专栏
补充：移动开发 , Android ,
