1、从官网下载源码

2、编辑一个config.h：

/* config.h.  Generated from config.h.in by configure.  */
/* config.h.in.  Generated from configure.in by autoheader.  */

/* Define if you want to use libfaad together with Digital Radio Mondiale
   (DRM) */
/* #undef DRM */

/* Define if you want support for Digital Radio Mondiale (DRM) parametric
   stereo */
/* #undef DRM_PS */

/* 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 if needed */
/* #undef HAVE_FLOAT32_T */

/* Define to 1 if you have the <float.h> header file. */
#define HAVE_FLOAT_H 1

/* Define to 1 if you have the `getpwuid' function. */
#define HAVE_GETPWUID 1

/* Define to 1 if you have the <inttypes.h> header file. */
#define HAVE_INTTYPES_H 1

/* Define if you have the IOKit API */
/* #undef HAVE_IOKIT_IOKITLIB_H */

/* Define to 1 if you have the <limits.h> header file. */
#define HAVE_LIMITS_H 1

/* Define if you have C99's lrintf function. */
#define HAVE_LRINTF 1

/* Define to 1 if you have the <mathf.h> header file. */
/* #undef HAVE_MATHF_H */

/* Define to 1 if you have the `memcpy' function. */
#define HAVE_MEMCPY 1

/* Define to 1 if you have the <memory.h> header file. */
#define HAVE_MEMORY_H 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 `strchr' function. */
#define HAVE_STRCHR 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 `strsep' function. */
#define HAVE_STRSEP 1

/* Define to 1 if you have the <sysfs/libsysfs.h> header file. */
/* #undef HAVE_SYSFS_LIBSYSFS_H */

/* 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/time.h> header file. */
#define HAVE_SYS_TIME_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 the <unistd.h> header file. */
#define HAVE_UNISTD_H 1

/* Define to 1 if your C compiler doesn't accept -c and -o together. */
/* #undef NO_MINUS_C_MINUS_O */

/* Name of package */
#define PACKAGE "faad2"

/* Define to the address where bug reports for this package should be sent. */
#define PACKAGE_BUGREPORT ""

/* Define to the full name of this package. */
#define PACKAGE_NAME ""

/* Define to the full name and version of this package. */
#define PACKAGE_STRING ""

/* Define to the one symbol short name of this package. */
#define PACKAGE_TARNAME ""

/* Define to the version of this package. */
#define PACKAGE_VERSION ""

/* Define to 1 if you have the ANSI C header files. */
#define STDC_HEADERS 1

/* Define to 1 if you can safely include both <sys/time.h> and <time.h>. */
#define TIME_WITH_SYS_TIME 1

/* Version number of package */
#define VERSION "2.7.0"

/* 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 `__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 `long int' if <sys/types.h> does not define. */
/* #undef off_t */

LOCAL_PATH := $(call my-dir)

include $(CLEAR_VARS)

LOCAL_MODULE:= faad
LOCAL_ARM_MODE := arm

LOCAL_C_INCLUDES := 				$(LOCAL_PATH)					$(LOCAL_PATH)/include			$(LOCAL_PATH)/libfaad			$(LOCAL_PATH)/common/mp4ff		$(LOCAL_PATH)/libfaad/codebook

LOCAL_SRC_FILES := 						libfaad/bits.c  				libfaad/cfft.c  				libfaad/decoder.c 				libfaad/drc.c     			    libfaad/drm_dec.c 				libfaad/error.c 				libfaad/filtbank.c 				libfaad/ic_predict.c 			libfaad/is.c 					libfaad/lt_predict.c 			libfaad/mdct.c	 				libfaad/mp4.c 					libfaad/ms.c 					libfaad/output.c 				libfaad/pns.c 					libfaad/ps_dec.c 				libfaad/ps_syntax.c 			libfaad/pulse.c 				libfaad/specrec.c 				libfaad/syntax.c 				libfaad/tns.c 					libfaad/hcr.c 					libfaad/huffman.c 				libfaad/rvlc.c 					libfaad/ssr.c 					libfaad/ssr_fb.c 				libfaad/ssr_ipqf.c 				libfaad/common.c 				libfaad/sbr_dct.c 				libfaad/sbr_e_nf.c 				libfaad/sbr_fbt.c 				libfaad/sbr_hfadj.c 			libfaad/sbr_hfgen.c 			libfaad/sbr_huff.c 				libfaad/sbr_qmf.c 				libfaad/sbr_syntax.c 			libfaad/sbr_tf_grid.c 			libfaad/sbr_dec.c				common/mp4ff/mp4atom.c			common/mp4ff/mp4ff.c			common/mp4ff/mp4meta.c			common/mp4ff/mp4sample.c 		common/mp4ff/mp4tagupdate.c			common/mp4ff/mp4util.c				com_iflytek_codec_aac_FaadAACNativeDecoder.c
		
LOCAL_CFLAGS:= -DHAVE_CONFIG_H
LOCAL_LDLIBS := -llog

include $(BUILD_SHARED_LIBRARY)

5、定点化：

上面编译的是浮点的，可以编译成定点的，方法是把faad/libfaad/common.h中的两个宏打开：

#define FIXED_POINT
#define BIG_IQ_TABLE