操做系統:Linux (window我還沒試過哦)html
1.建立一個新的Android Project 命名爲FFmpegTestjava
目標平臺最好選擇與編譯好的libffmpeg.so相同的平臺,在FFmpegTest目錄下建立一個jni目錄。linux
2.下載ffmpeg源代碼並放到jni目錄下android
下載地址:http://ffmpeg.org/download.html 這是0.8 「Love」版本的ffmpeg,若是你想獲取最新版本的ffmpeg源代碼能夠經過Git或者SVN獲取(具體問google)。shell
下載完後放到jni目錄下的ffmpeg目錄。ubuntu
3.編譯ffmpegbash
3.1複製粘貼如下腳本代碼,保存命名爲 build_android.sh ,並放到ffmpeg目錄下。app
注意:這幾行代碼是須要修改的ide
NDK=~/Desktop/android/android-ndk-r5b PLATFORM=$NDK/platforms/android-8/arch-arm/ PREBUILT=$NDK/toolchains/arm-linux-androideabi-4.4.3/prebuilt/linux-x86
根據你本身的狀況指定NDK的各個目錄,你也能夠根據你項目的目標平臺調整 PLATFORM 變量的值, SDK 2.2 對應的是android-8.函數
#!/bin/bash ###################################################### # Usage: # put this script in top of FFmpeg source tree # ./build_android # It generates binary for following architectures: # ARMv6 # ARMv6+VFP # ARMv7+VFPv3-d16 (Tegra2) # ARMv7+Neon (Cortex-A8) # Customizing: # 1. Feel free to change ./configure parameters for more features # 2. To adapt other ARM variants # set $CPU and $OPTIMIZE_CFLAGS # call build_one ###################################################### NDK=/home/guokai/workspace/ffmpeg-test/android-ndk-r8/ PLATFORM=$NDK/platforms/android-14/arch-arm/ PREBUILT=$NDK/toolchains/arm-linux-androideabi-4.4.3/prebuilt/linux-x86/ function build_one { ./configure --target-os=linux \ --prefix=$PREFIX \ --enable-cross-compile \ --extra-libs="-lgcc" \ --arch=arm \ --cc=$PREBUILT/bin/arm-linux-androideabi-gcc \ --cross-prefix=$PREBUILT/bin/arm-linux-androideabi- \ --nm=$PREBUILT/bin/arm-linux-androideabi-nm \ --sysroot=$PLATFORM \ --extra-cflags=" -O3 -fpic -DANDROID -DHAVE_SYS_UIO_H=1 -Dipv6mr_interface=ipv6mr_ifindex -fasm -Wno-psabi -fno-short-enums -fno-strict-aliasing -finline-limit=300 $OPTIMIZE_CFLAGS " \ --disable-shared \ --enable-static \ --extra-ldflags="-Wl,-rpath-link=$PLATFORM/usr/lib -L$PLATFORM/usr/lib -nostdlib -lc -lm -ldl -llog" \ --disable-everything \ --enable-demuxer=mov \ --enable-demuxer=h264 \ --disable-ffplay \ --enable-protocol=file \ --enable-avformat \ --enable-avcodec \ --enable-decoder=rawvideo \ --enable-decoder=mjpeg \ --enable-decoder=h263 \ --enable-decoder=mpeg4 \ --enable-decoder=h264 \ --enable-parser=h264 \ --disable-network \ --enable-zlib \ --disable-avfilter \ --disable-avdevice \ $ADDITIONAL_CONFIGURE_FLAG make clean make -j4 install $PREBUILT/bin/arm-linux-androideabi-ar d libavcodec/libavcodec.a inverse.o $PREBUILT/bin/arm-linux-androideabi-ld -rpath-link=$PLATFORM/usr/lib -L$PLATFORM/usr/lib -soname libffmpeg.so -shared -nostdlib -z,noexecstack -Bsymbolic --whole-archive --no-undefined -o $PREFIX/libffmpeg.so libavcodec/libavcodec.a libavformat/libavformat.a libavutil/libavutil.a libswscale/libswscale.a -lc -lm -lz -ldl -llog --warn-once --dynamic-linker=/system/bin/linker $PREBUILT/lib/gcc/arm-linux-androideabi/4.4.3/libgcc.a } #arm v6 #CPU=armv6 #OPTIMIZE_CFLAGS="-marm -march=$CPU" #PREFIX=./android/$CPU #ADDITIONAL_CONFIGURE_FLAG= #build_one #arm v7vfpv3 CPU=armv7-a OPTIMIZE_CFLAGS="-mfloat-abi=softfp -mfpu=vfpv3-d16 -marm -march=$CPU " PREFIX=./android/$CPU ADDITIONAL_CONFIGURE_FLAG= build_one #arm v7vfp #CPU=armv7-a #OPTIMIZE_CFLAGS="-mfloat-abi=softfp -mfpu=vfp -marm -march=$CPU " #PREFIX=./android/$CPU-vfp #ADDITIONAL_CONFIGURE_FLAG= #build_one #arm v7n #CPU=armv7-a #OPTIMIZE_CFLAGS="-mfloat-abi=softfp -mfpu=neon -marm -march=$CPU -mtune=cortex-a8" #PREFIX=./android/$CPU #ADDITIONAL_CONFIGURE_FLAG=--enable-neon #build_one #arm v6+vfp #CPU=armv6 #OPTIMIZE_CFLAGS="-DCMP_HAVE_VFP -mfloat-abi=softfp -mfpu=vfp -marm -march=$CPU" #PREFIX=./android/${CPU}_vfp #ADDITIONAL_CONFIGURE_FLAG= #build_one
爲了提升編譯速度此腳本放棄了ffmpeg的不少東西,你能夠根據本身的需求改變腳本文件的配置,此外,你還能夠編譯多硬件平臺的庫文件,本例只編譯 arm v7vfpv3,由於編譯arm的庫速度比較快~~╮(╯▽╰)╭ 請原諒 湯姆貓的懶惰。
3.2 確保 bash 腳本文件是可執行的. Linux系統使用終端進入項目jin目錄下的ffmpeg目錄,輸入如下命令:
sudo chmod 755 build_android.sh ,這樣就能確保腳本文件時可執行的啦~
3.3 使用終端執行腳本文件.
進入到 bash 腳本文件所在目錄也就是jni/ffmpeg下,輸入如下命令
./build_android.sh
執行腳本文件(應該是幾分鐘就編譯完成了)。
注意:NDK-r6或者以上的版本若是沒法編譯經過,能夠試試下面這個腳本文件
<span style="color:#333333;">#!/bin/bash ###################################################### # Usage: # put this script in top of FFmpeg source tree # ./build_android # # It generates binary for following architectures: # ARMv6 # ARMv6+VFP # ARMv7+VFPv3-d16 (Tegra2) # ARMv7+Neon (Cortex-A8) # # Customizing: # 1. Feel free to change ./configure parameters for more features # 2. To adapt other ARM variants # set $CPU and $OPTIMIZE_CFLAGS # call build_one ###################################################### #change these three lines if you want to build using different vesion of Android ndk #build_one is for ndk 5, and build_one_r6 is for ndk 6 NDK=~/ffmpeg/android-ndk-r6 PLATFORM=$NDK/platforms/android-8/arch-arm/ PREBUILT=$NDK/toolchains/arm-linux-androideabi-4.4.3/prebuilt/linux-x86 function build_one_r6 { ./configure \ --disable-shared \ --enable-static \ --enable-gpl \ --enable-version3 \ --enable-nonfree \ --disable-doc \ --disable-ffmpeg \ --disable-ffplay \ --disable-ffprobe \ --disable-ffserver \ --disable-avdevice \ --disable-avfilter \ --disable-postproc \ --enable-small \ --cross-prefix=$PREBUILT/bin/arm-linux-androideabi- \ --enable-cross-compile \ --target-os=linux \ --extra-cflags="-I$PLATFORM/usr/include" \ --extra-ldflags="-L$PLATFORM/usr/lib -nostdlib" \ --arch=arm \ --disable-symver \ --disable-debug \ --disable-stripping \ $ADDITIONAL_CONFIGURE_FLAG sed -i 's/HAVE_LRINT 0/HAVE_LRINT 1/g' config.h sed -i 's/HAVE_LRINTF 0/HAVE_LRINTF 1/g' config.h sed -i 's/HAVE_ROUND 0/HAVE_ROUND 1/g' config.h sed -i 's/HAVE_ROUNDF 0/HAVE_ROUNDF 1/g' config.h sed -i 's/HAVE_TRUNC 0/HAVE_TRUNC 1/g' config.h sed -i 's/HAVE_TRUNCF 0/HAVE_TRUNCF 1/g' config.h make clean make -j4 install $PREBUILT/bin/arm-linux-androideabi-ar d libavcodec/libavcodec.a inverse.o $PREBUILT/bin/arm-linux-androideabi-ld -rpath-link=$PLATFORM/usr/lib -L$PLATFORM/usr/lib -soname libffmpeg.so -shared -nostdlib -z,noexecstack -Bsymbolic --whole-archive --no-undefined -o $PREFIX/libffmpeg.so libavcodec/libavcodec.a libavformat/libavformat.a libavutil/libavutil.a libswscale/libswscale.a -lc -lm -lz -ldl -llog --warn-once --dynamic-linker=/system/bin/linker $PREBUILT/lib/gcc/arm-linux-androideabi/4.4.3/libgcc.a } function build_one_r6_2 { $PREBUILT/bin/arm-linux-androideabi-ar d libavcodec/libavcodec.a inverse.o $PREBUILT/bin/arm-linux-androideabi-ld -rpath-link=$PLATFORM/usr/lib -L$PLATFORM/usr/lib -soname libffmpeg.so -shared -nostdlib -z,noexecstack -Bsymbolic --whole-archive --no-undefined -o $PREFIX/libffmpeg.so libavcodec/libavcodec.a libavformat/libavformat.a libavutil/libavutil.a libswscale/libswscale.a -lc -lm -lz -ldl -llog --warn-once --dynamic-linker=/system/bin/linker $PREBUILT/lib/gcc/arm-linux-androideabi/4.4.3/libgcc.a } #arm v6 #CPU=armv6 #OPTIMIZE_CFLAGS="-marm -march=$CPU" #PREFIX=./android/$CPU #ADDITIONAL_CONFIGURE_FLAG= #build_one #arm v7vfpv3 CPU=armv7-a OPTIMIZE_CFLAGS="-mfloat-abi=softfp -mfpu=vfpv3-d16 -marm -march=$CPU " PREFIX=./android/$CPU ADDITIONAL_CONFIGURE_FLAG= #build_one build_one_r6 #arm v7vfp #CPU=armv7-a #OPTIMIZE_CFLAGS="-mfloat-abi=softfp -mfpu=vfp -marm -march=$CPU " #PREFIX=./android/$CPU-vfp #ADDITIONAL_CONFIGURE_FLAG= #build_one #arm v7n #CPU=armv7-a #OPTIMIZE_CFLAGS="-mfloat-abi=softfp -mfpu=neon -marm -march=$CPU -mtune=cortex-a8" #PREFIX=./android/$CPU #ADDITIONAL_CONFIGURE_FLAG=--enable-neon #build_one #arm v6+vfp #CPU=armv6 #OPTIMIZE_CFLAGS="-DCMP_HAVE_VFP -mfloat-abi=softfp -mfpu=vfp -marm -march=$CPU" #PREFIX=./android/${CPU}_vfp #ADDITIONAL_CONFIGURE_FLAG= #build_one</span>
網上說可能還須要在ffmpeg目錄下建立 ./android/armv7-a/的目錄結構.
4.完成編譯
當腳本文件執行完畢,會在ffmpeg目錄下生成一個android的文件夾,裏面就包含了全部的編譯成果。
5.將編譯完成的.so或.a庫,使用JNI規範集成到android應用中供java代碼調用。
5.1下面的代碼是調用ffmpeg庫的jni層代碼,能夠在jni目錄下建立一個ffmpeg-test-jni.c文件,將代碼粘貼過去,文章末尾會提供 本例完整的工程項目的 下載連接。。
/** this is the wrapper of the native functions **/ /*android specific headers*/ #include <jni.h> #include <android/log.h> #include <android/bitmap.h> /*standard library*/ #include <time.h> #include <math.h> #include <limits.h> #include <stdio.h> #include <stdlib.h> #include <inttypes.h> #include <unistd.h> #include <assert.h> /*ffmpeg headers*/ #include <libavutil/avstring.h> #include <libavutil/pixdesc.h> #include <libavutil/imgutils.h> #include <libavutil/samplefmt.h> #include <libavformat/avformat.h> #include <libswscale/swscale.h> #include <libavcodec/avcodec.h> #include <libavcodec/opt.h> #include <libavcodec/avfft.h> /*for android logs*/ #define LOG_TAG "FFmpegTest" #define LOG_LEVEL 10 #define LOGI(level, ...) if (level <= LOG_LEVEL) {__android_log_print(ANDROID_LOG_INFO, LOG_TAG, __VA_ARGS__);} #define LOGE(level, ...) if (level <= LOG_LEVEL) {__android_log_print(ANDROID_LOG_ERROR, LOG_TAG, __VA_ARGS__);} /**/ char *gFileName; //the file name of the video AVFormatContext *gFormatCtx; int gVideoStreamIndex; //video stream index AVCodecContext *gVideoCodecCtx; static void get_video_info(char *prFilename); /*parsing the video file, done by parse thread*/ static void get_video_info(char *prFilename) { AVCodec *lVideoCodec; int lError; /*some global variables initialization*/ LOGI(10, "get video info starts!"); /*register the codec*/ extern AVCodec ff_h263_decoder; avcodec_register(&ff_h263_decoder); extern AVCodec ff_h264_decoder; avcodec_register(&ff_h264_decoder); extern AVCodec ff_mpeg4_decoder; avcodec_register(&ff_mpeg4_decoder); extern AVCodec ff_mjpeg_decoder; avcodec_register(&ff_mjpeg_decoder); /*register parsers*/ //extern AVCodecParser ff_h264_parser; //av_register_codec_parser(&ff_h264_parser); //extern AVCodecParser ff_mpeg4video_parser; //av_register_codec_parser(&ff_mpeg4video_parser); /*register demux*/ extern AVInputFormat ff_mov_demuxer; av_register_input_format(&ff_mov_demuxer); //extern AVInputFormat ff_h264_demuxer; //av_register_input_format(&ff_h264_demuxer); /*register the protocol*/ extern URLProtocol ff_file_protocol; av_register_protocol2(&ff_file_protocol, sizeof(ff_file_protocol)); /*open the video file--根據文件名來初始化AVFormatContext*/ if ((lError = av_open_input_file(&gFormatCtx, gFileName, NULL, 0, NULL)) !=0 ) { LOGE(1, "Error open video file: %d", lError); return; //open file failed } /*retrieve stream information--從AVFormatContext提取流信息*/ if ((lError = av_find_stream_info(gFormatCtx)) < 0) { LOGE(1, "Error find stream information: %d", lError); return; } /*find the video stream and its decoder--經過AVFormatContext找到文件的stream和編碼類型*/ gVideoStreamIndex = av_find_best_stream(gFormatCtx, AVMEDIA_TYPE_VIDEO, -1, -1, &lVideoCodec, 0); if (gVideoStreamIndex == AVERROR_STREAM_NOT_FOUND) { LOGE(1, "Error: cannot find a video stream"); return; } else { LOGI(10, "video codec: %s", lVideoCodec->name); } if (gVideoStreamIndex == AVERROR_DECODER_NOT_FOUND) { LOGE(1, "Error: video stream found, but no decoder is found!"); return; } /*open the codec--從編碼類型打開解碼器*/ gVideoCodecCtx = gFormatCtx->streams[gVideoStreamIndex]->codec; LOGI(10, "open codec: (%d, %d)", gVideoCodecCtx->height, gVideoCodecCtx->width); #ifdef SELECTIVE_DECODING gVideoCodecCtx->allow_selective_decoding = 1; #endif if (avcodec_open(gVideoCodecCtx, lVideoCodec) < 0) {/*用找的編碼類別lVideoCodec類初始化AVCodecContext*/ LOGE(1, "Error: cannot open the video codec!"); return; } LOGI(10, "get video info ends"); } JNIEXPORT void JNICALL Java_roman10_ffmpegTest_VideoBrowser_naClose(JNIEnv *pEnv, jobject pObj) { int l_mbH = (gVideoCodecCtx->height + 15) / 16; /*close the video codec*/ avcodec_close(gVideoCodecCtx); /*close the video file*/ av_close_input_file(gFormatCtx); } JNIEXPORT void JNICALL Java_roman10_ffmpegTest_VideoBrowser_naInit(JNIEnv *pEnv, jobject pObj, jstring pFileName) { int l_mbH, l_mbW; /*get the video file name*/ gFileName = (char *)(*pEnv)->GetStringUTFChars(pEnv, pFileName, NULL); if (gFileName == NULL) { LOGE(1, "Error: cannot get the video file name!"); return; } LOGI(10, "video file name is %s", gFileName); get_video_info(gFileName); LOGI(10, "initialization done"); } JNIEXPORT jstring JNICALL Java_roman10_ffmpegTest_VideoBrowser_naGetVideoCodecName(JNIEnv *pEnv, jobject pObj) { char* lCodecName = gVideoCodecCtx->codec->name; return (*pEnv)->NewStringUTF(pEnv, lCodecName); } JNIEXPORT jstring JNICALL Java_roman10_ffmpegTest_VideoBrowser_naGetVideoFormatName(JNIEnv *pEnv, jobject pObj) { char* lFormatName = gFormatCtx->iformat->name; return (*pEnv)->NewStringUTF(pEnv, lFormatName); } JNIEXPORT jintArray JNICALL Java_roman10_ffmpegTest_VideoBrowser_naGetVideoResolution(JNIEnv *pEnv, jobject pObj) { jintArray lRes; lRes = (*pEnv)->NewIntArray(pEnv, 2); if (lRes == NULL) { LOGI(1, "cannot allocate memory for video size"); return NULL; } jint lVideoRes[2]; lVideoRes[0] = gVideoCodecCtx->width; lVideoRes[1] = gVideoCodecCtx->height; (*pEnv)->SetIntArrayRegion(pEnv, lRes, 0, 2, lVideoRes); return lRes; }
若是你不熟悉java的JNI開發, 你可能須要先閱讀JNI規範後才能看懂以上的代碼。
5.2編譯本地代碼,將ffmpeg.so集成到本身的.so庫
在jni目錄下建立一個 Android.mk 文件,此文件是用於告訴NDK如何去編譯這個項目的jni層代碼
LOCAL_PATH := $(call my-dir) #declare the prebuilt library include $(CLEAR_VARS) LOCAL_MODULE := ffmpeg-prebuilt LOCAL_SRC_FILES := ffmpeg-0.8/android/armv7-a/libffmpeg.so LOCAL_EXPORT_C_INCLUDES := ffmpeg-0.8/android/armv7-a/include LOCAL_EXPORT_LDLIBS := ffmpeg-0.8/android/armv7-a/libffmpeg.so LOCAL_PRELINK_MODULE := true # 該模塊是否被啓動就加載。該項設置依具體程序的特性而定。 include $(PREBUILT_SHARED_LIBRARY) #the ffmpeg-test-jni library include $(CLEAR_VARS) LOCAL_ALLOW_UNDEFINED_SYMBOLS=false LOCAL_MODULE := ffmpeg-test-jni #當前模塊的名稱,也就是第一步中咱們提到的LIBNAME。 #注意這個須要加上lib前綴,但不須要加.so後綴,也就是說應該是libLIBNAME LOCAL_SRC_FILES := ffmpeg-test-jni.c # 包含的源文件 LOCAL_C_INCLUDES := $(LOCAL_PATH)/ffmpeg-0.8/android/armv7-a/include #包含的頭文件。這裏是須要包含JNI的頭文件。 LOCAL_SHARED_LIBRARY := ffmpeg-prebuilt # 當前模塊須要依賴的共享庫 LOCAL_LDLIBS := -llog -ljnigraphics -lz -lm $(LOCAL_PATH)/ffmpeg-0.8/android/armv7-a/libffmpeg.so include $(BUILD_SHARED_LIBRARY)
再在jni目錄新建另外一個新的文件命名爲 Application.mk,代碼以下:
# The ARMv7 is significanly faster due to the use of the hardware FPU APP_ABI := armeabi-v7a APP_PLATFORM := android-8
關於Android.mk 與 Application.mk的更多信息請參考 android NDK的官方文檔 .
如今你的工程目錄結構應該是醬紫的....
5.3 編寫java native 方法調用 本地代碼(Native Code)
要調用本地方法也就是.so庫中的方法,須要先把.so加載到虛擬機中,如下是代碼片斷,後面會提供項目的下載連接
/*this part communicates with native code through jni (java native interface)*/ //load the native library static { System.loadLibrary("ffmpeg"); System.loadLibrary("ffmpeg-test-jni"); } //declare the jni functions private static native void naInit(String _videoFileName); private static native int[] naGetVideoResolution(); private static native String naGetVideoCodecName(); private static native String naGetVideoFormatName(); private static native void naClose(); private void showVideoInfo(final File _file) { String videoFilename = _file.getAbsolutePath(); naInit(videoFilename); int[] prVideoRes = naGetVideoResolution(); String prVideoCodecName = naGetVideoCodecName(); String prVideoFormatName = naGetVideoFormatName(); naClose(); String displayText = "Video: " + videoFilename + "\n"; displayText += "Video Resolution: " + prVideoRes[0] + "x" + prVideoRes[1] + "\n"; displayText += "Video Codec: " + prVideoCodecName + "\n"; displayText += "Video Format: " + prVideoFormatName + "\n"; text_titlebar_text.setText(displayText); }
這幾個java 的native方法與上面實現的c 代碼中的幾個方法是一 一對應的,或者你能夠先在命令行中cd 到工程的classes目錄下使用javah工具生成這些java native方法對應的.h頭文件,再新建一個.c文件將.h文件include進來再一 一去實現其中的函數。.h頭文件並非必須的...但生成.h文件比較規範.
5.4 編譯集成ffmpeg 這一步在5.3以前作也能夠...
Android.mk 、Application.mk、ffmpeg-test-jni.c、ffmpeg/android中的庫文件都準備齊全後,
使用終端cd 到工程目錄(FFmpegTest) 執行命令:
ndk-build
出現以上提示則表示編譯經過了 ╮(╯▽╰)╭ 終於搞定了
刷新工程目錄後會生成一個libs文件夾,裏面就包含了咱們編譯好的.so庫
6.最後安裝應用開始測試吧~
項目工程下載: http://download.csdn.net/detail/teisun/4276777
個人開發環境是ubuntu 10.04 和ndk-r五、ndk-r六、 ndk-r7都測試經過,window平臺不敢保證能夠 順利編譯哦。