Android NDK & FFMPEG build

Question

I am trying to create the FFMPEG library for my Android application using the NDK. I downloaded the source code from this site, and I think I am creating it (this is my first attempt to work with NDK and ffmpeg). I created a build.sh file that I use to execute it from the command line on Mac OS X. But I have a few questions ...

First of all, I know that I need an Android.mk file, so I can use the built-in library in my application, but I don’t know how to do this for the reasons I mentioned above. After running build.sh I get an android folder with several folders and some libraries. So my first question is: how can I create the Android.mk file that I need ... and maybe if someone can explain to me why I need it.

My second question is: I need some libraries from ffmpeg to use them from my application, but after the build, I do not see them in my source tree. I know that I need to include them in my build.sh , and I think I did, but I can’t see them. Therefore, any information about my assembly file will be useful for me to understand how to configure it. Here's what it looks like:

  #!/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 $OPTIMIZE_CFLAGS # call build_one ###################################################### NDK=~/Desktop/android-ndk-r5b PLATFORM=$NDK/platforms/android-8/arch-arm/ PREBUILT=$NDK/toolchains/arm-linux-androideabi-4.4.3/prebuilt/darwin-x86 function build_one { ./configure \ --target-os=darwin \ --prefix=$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 $OPTIMIZE_CFLAGS " \ --disable-doc \ --disable-ffmpeg \ --disable-ffplay \ --disable-ffserver \ --disable-ffprobe \ --extra-ldflags="-Wl,-rpath-link=$PLATFORM/usr/lib -L$PLATFORM/usr/lib -nostdlib -lc -lm -ldl -llog" \ --enable-zlib \ --enable-version3 \ --enable-nonfree \ --enable-libmp3lame \ --enable-libspeex \ --enable-libtheora \ --enable-libfaac \ --enable-libvorbis \ --enable-libaacplus \ --prefix=$DIST_DIR \ $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 

Thanks for any useful information / suggestions / examples, etc.

Answer 1

I made a tutorial on how to build ffmpeg and x264 for android : zip with ffmpeg build with x264

You can also download a zip file containing the files needed to create an android application.

Answer 2

If you want more detailed instructions on how to build ffmpeg and how to use it to create Android applications, see the cookbook for Android NDK: http://www.packtpub.com/android-native-development-kit-cookbook / book

Bonus Chapter 1 is dedicated to developing multimedia applications with Android NDK and ffmpeg, and it is available for free at http://www.packtpub.com/sites/default/files/downloads/Developing_Multimedia_Applications_with_NDK.pdf p>

Answer 3

First of all, you should read the documentation for the Android NDK and check out some sample applications. You will find this data in the files android_NDK_home / docs and android_NDK_home / samples (where android_NDK_home is the name of the folder for your Android NDK).

Also check this link on stackoverflow: Using FFmpeg with Android-NDK

For learning step-by-step instructions, this is pretty good: http://www.roman10.net/how-to-build-ffmpeg-for-android/

In addition, you will need to install / configure some elements in Eclipse to enable support for developing applications created using the NDK: http://mhandroid.wordpress.com/2011/01/23/using-eclipse-for-android- cc-development / http://wiki.eclipse.org/Sequoyah/ndk_checklist

And a pretty good project that uses the ffmpeg library: https://github.com/havlenapetr/FFMpeg

Answer 4

ffmpeg uses autoconf as its build system. At the time of this writing, no one has yet compiled the Gradle package for ffmpeg on Android. As far as I can tell, Gradle does not yet support autoconf, which makes it pretty difficult to do

Nevertheless, having tried several tutorials that were there, as well as some of the ready-made packages, we decided to turn over our own Android shell script for ffmpeg, which includes support for OpenSSL and librtmp .

You can find it here: https://github.com/cine-io/android-ffmpeg-with-rtmp

Prerequisites: Android NDK must be installed

Instruction:

 $ git clone [e-mail] :cine-io/android-ffmpeg-with-rtmp.git $ cd android-ffmpeg-with-rtmp $ ./build.sh 

When the script finishes, the required libraries and the ffmpeg executable will be placed in the build/dist directory. You can include them in your project just like any other native binary.

Answer 5

To build the ffmpeg executable, I use the following Android.mk :

 SYSROOT-armeabi-v7a := $(NDK_ROOT)/platforms/android-9/arch-arm/ SYSROOT-arm64-v8a := $(NDK_ROOT)/platforms/android-21/arch-arm64/ SYSROOT-x86 := $(NDK_ROOT)/platforms/android-9/arch-x86/ SYSROOT := $(SYSROOT-$(TARGET_ARCH_ABI)) TOOLCHAIN_TARGET_ARCH-armeabi-v7a := arm TOOLCHAIN_TARGET_ARCH-arm64-v8a := aarch64 TOOLCHAIN_TARGET_ARCH-x86 := i686 TOOLCHAIN_TARGET_ARCH := $(TOOLCHAIN_TARGET_ARCH-$(TARGET_ARCH_ABI)) TOOLCHAIN_TARGET_ABI-armeabi-v7a := androideabi TOOLCHAIN_TARGET_ABI-arm64-v8a := android TOOLCHAIN_TARGET_ABI-x86 := android TOOLCHAIN_TARGET_ABI := $(TOOLCHAIN_TARGET_ABI-$(TARGET_ARCH_ABI)) TOOLCHAIN_TRIPLET := $(TOOLCHAIN_TARGET_ARCH)-linux-$(TOOLCHAIN_TARGET_ABI)- TOOLCHAIN_NAME-$(TARGET_ARCH_ABI) := $(TOOLCHAIN_TRIPLET)$(TOOLCHAIN_VERSION) TOOLCHAIN_NAME-x86 := x86-$(TOOLCHAIN_VERSION) TOOLCHAIN_NAME := $(TOOLCHAIN_NAME-$(TARGET_ARCH_ABI)) TOOLCHAIN_VERSION_PREFIX := $(TOOLCHAIN_TRIPLET)$(TOOLCHAIN_VERSION) ARCH_ARM_MODE-armeabi := arm ARCH_ARM_MODE-armeabi-v7a := thumb ARCH_ARM_MODE-arm64-v8a := thumb ARCH_ARM_MODE := $(ARCH_ARM_MODE-$(TARGET_ARCH_ABI)) include $(CLEAR_VARS) LOCAL_ARM_MODE := $(ARCH_ARM_MODE) FFMPEG_PATH := $(BUILD_DIRECTORY)/ffmpeg LOCAL_CFLAGS-armeabi-v7a := -march=armv7-a -mfpu=vfpv3-d16 -mfloat-abi=softfp LOCAL_CFLAGS-x86 := -m32 LOCAL_CFLAGS-arm64-v8a := -march=armv8-a+simd+fp LOCAL_CFLAGS := $(LOCAL_CFLAGS-$(TARGET_ARCH_ABI)) LOCAL_LDFLAGS-x86 := -m32 -Wl,-eh-frame-hdr -Wl,-m,elf_i386 -Wl,-z,noexecstack -Wl,-z,relro -Wl,-z,now LOCAL_LDFLAGS := $(LOCAL_LDFLAGS-$(TARGET_ARCH_ABI)) LOCAL_CFLAGS += -fPIE LOCAL_LDFLAGS += -fPIE -pie FFMPEG_CONFIG_OPTS := FFMPEG_CONFIG_OPTS += --target-os=linux FFMPEG_CONFIG_OPTS-$(TARGET_ARCH_ABI) := --cross-prefix=$(TOOLCHAIN_PREFIX) FFMPEG_CONFIG_OPTS-$(TARGET_ARCH_ABI) += --enable-cross-compile FFMPEG_CONFIG_OPTS-$(TARGET_ARCH_ABI) += --sysroot=$(SYSROOT) FFMPEG_CONFIG_OPTS += $(FFMPEG_CONFIG_OPTS-$(TARGET_ARCH_ABI)) ## disable FFMPEG_CONFIG_OPTS += --disable-doc FFMPEG_CONFIG_OPTS += --disable-shared FFMPEG_CONFIG_OPTS += --disable-avdevice FFMPEG_CONFIG_OPTS += --disable-postproc FFMPEG_CONFIG_OPTS += --disable-network FFMPEG_CONFIG_OPTS += --disable-iconv FFMPEG_CONFIG_OPTS += --disable-zlib FFMPEG_CONFIG_OPTS += --disable-ffplay FFMPEG_CONFIG_OPTS += --disable-ffprobe FFMPEG_CONFIG_OPTS += --disable-ffserver FFMPEG_CONFIG_OPTS += --disable-swscale-alpha ## enable FFMPEG_CONFIG_OPTS += --enable-pthreads FFMPEG_CONFIG_OPTS += --enable-small FFMPEG_CONFIG_OPTS += --extra-cflags="$(LOCAL_CFLAGS)" FFMPEG_CONFIG_OPTS += --extra-cxxflags="$(LOCAL_CXXFLAGS)" FFMPEG_CONFIG_OPTS += --extra-ldflags="$(LOCAL_LDFLAGS)" FFMPEG_CONFIG_OPTS += --enable-runtime-cpudetect ARMBITS-$(TARGET_ARCH_ABI) := ARMBITS-arm64-v8a := 64 ARMBITS := $(ARMBITS-$(TARGET_ARCH_ABI)) FFMPEG_CONFIG_OPTS-$(TARGET_ARCH_ABI) := FFMPEG_CONFIG_OPTS-armeabi := --enable-armv5te FFMPEG_CONFIG_OPTS-armeabi += --enable-inline-asm FFMPEG_CONFIG_OPTS-armeabi += --arch=arm$(ARMBITS) FFMPEG_CONFIG_OPTS-armeabi-v7a := $(FFMPEG_CONFIG_OPTS-armeabi) FFMPEG_CONFIG_OPTS-armeabi-v7a += --enable-armv6 FFMPEG_CONFIG_OPTS-armeabi-v7a += --enable-armv6t2 FFMPEG_CONFIG_OPTS-armeabi-v7a += --enable-vfp FFMPEG_CONFIG_OPTS-armeabi-v7a += --enable-neon FFMPEG_CONFIG_OPTS-armeabi-v7a += --enable-thumb FFMPEG_CONFIG_OPTS-armeabi-v7a += --enable-fast-unaligned FFMPEG_CONFIG_OPTS-arm64-v8a := $(FFMPEG_CONFIG_OPTS-armeabi-v7a) FFMPEG_CONFIG_OPTS-x86 := --enable-yasm FFMPEG_CONFIG_OPTS-x86 += --arch=x86 FFMPEG_CONFIG_OPTS += $(FFMPEG_CONFIG_OPTS-$(TARGET_ARCH_ABI)) LOCAL_MODULE := ffmpeg LOCAL_SRC_FILES := $(abspath $(TARGET_OBJS))/ffmpeg/lib...ffmpeg...so # see http://stackoverflow.com/a/17384650/192373 clean: $(TARGET_OBJS)/ffmpeg/clean $(TARGET_OBJS)/ffmpeg/clean: PRIVATE_ABI := $(FFMPEG_TARGET_ABI) $(TARGET_OBJS)/ffmpeg/clean: $(call host-echo-build-step,$(PRIVATE_ABI),Clean) "ffmpeg [$(PRIVATE_ABI)]" $(hide) $(call host-rmdir,$(@D)) $(shell $(call host-mkdir,$(dir $(LOCAL_SRC_FILES)))) $(shell $(HOST_ECHO) >$(LOCAL_SRC_FILES)) .PHONY: $(LOCAL_SRC_FILES) $(LOCAL_SRC_FILES): $(TARGET_OBJS)/ffmpeg/ffmpeg $(hide) $(call host-mv,$<, $@ ) include $(PREBUILT_SHARED_LIBRARY) $(TARGET_OBJS)/ffmpeg/Makefile: FFMPEG_CONFIG_OPTS := $(FFMPEG_CONFIG_OPTS) $(TARGET_OBJS)/ffmpeg/Makefile: $(hide) $(call host-mkdir,$(@D)) $(hide) cd $(@D) && $(abspath $(FFMPEG_PATH))/configure $(FFMPEG_CONFIG_OPTS) $(TARGET_OBJS)/ffmpeg/ffmpeg: FFMPEG_CONFIG_OPTS := using toolchain:$(NDK_ROOT)/toolchains/$(TOOLCHAIN_NAME) compiler:$(TOOLCHAIN_COMPILER) triplet:$(TOOLCHAIN_TRIPLET) $(TARGET_OBJS)/ffmpeg/ffmpeg: $(TARGET_OBJS)/ffmpeg/Makefile @echo $(FFMPEG_CONFIG_OPTS) $(hide) $(MAKE) --no-print-directory -C $(@D)