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• X264 & ARM encoding on Android

  20 janvier 2013, par Tishu

  I recently built a Video encoding class that runs on Android using ffmpeg and native code. I am surprised by the time it takes to encode a video, about 1 frame / second at best. I have tried with x264 and settings optimised for speed and with mpeg as well - no real difference.

  The x264 library now has support for ARM architecture and is meant to be quite efficient on these boasting over 20fps encoding speed. I am not sure I am using it correctly. Here the script I use for compiling :

  ./configure --prefix=$PREFIX \
  
  --enable-shared \
  
  --enable-static \
  
  --disable-gpac \
  
  --enable-debug \
  
  --extra-cflags=" -I$ARM_INC -fPIC -DANDROID -fpic -mthumb-interwork -ffunction-sections -funwind-tables -fno-short-enums -D__ARM_ARCH_5__ -D__ARM_ARCH_5T__ -D__ARM_ARCH_5E__ -D__ARM_ARCH_5TE__ -Wno-psabi -march=armv5te -msoft-float -mthumb -O3 -fomit-frame-pointer -fno-strict-aliasing -finline-limit=64 -DANDROID -Wa,--noexecstack -MMD -MP " \
  
  --extra-ldflags=" -nostdlib -Bdynamic -Wl,--no-undefined -Wl,-z,noexecstack -Wl,-z,nocopyreloc -Wl,-soname,/usr/lib/libz.so -Wl,-rpath-link=$ARM_LIB,-dynamic-linker=/system/bin/linker -L$ARM_LIB -lc -lm -ldl -lgcc" \
  
  --cross-prefix=${ARM_PRE}- \
  
  --disable-asm \
  
  --host=arm-linux \

  I believe the last line should so what I am after ie enable ARM optimisations. Maybe I am missing something.

  For info I am encoding a 640x480 video on a Nexus 7 tablet. Here are my encoder settings (x264)

  c->gop_size       = 12;
  
  c->pix_fmt        = PIX_FMT_YUV420P;
  
  c->max_b_frames   = 0;
  
  c->scenechange_threshold = 0;
  
  c->rc_buffer_size = 0;

  Thanks

• Android ffmpeg0.8 is not compiling with android ndk5 with cygwin compiler

  7 novembre 2013, par itsrajesh4uguys

  I am using the following tutorial for ffmpeg compilation .

  http://www.roman10.net/how-to-build-ffmpeg-for-android/

  I am followed all the instructions which they have provided. have changed the path in
  build_android.sh ,
  i am using android ndk5 and cygwing latest compiler.
  But i am facing following issue. .so file is not gets created .

  Krajesh@Rajesh /cygdrive/D/RAJESH-ANDROID/Rajesh-workspace/FFMPEG_2
  
  $ /cygdrive/d/Android_NDK/android-ndk-r5/ndk-build
  
  Prebuilt       : libffmpeg.so <= jni/ffmpeg-0.8/android/armv7-a/
  
  Install        : libffmpeg.so => libs/armeabi-v7a/libffmpeg.so
  
  install: cannot open `/cygdrive/D/RAJESH-ANDROID/Rajesh-workspace/FFMPEG_2/obj/local/armeabi-v7a/libffmpeg.so' for reading: Permission denied
  
  /cygdrive/d/Android_NDK/android-ndk-r5/build/core/build-binary.mk:305: recipe for target `/cygdrive/D/RAJESH-ANDROID/Rajesh-workspace/FFMPEG_2/libs/armeabi-v7a/libffmpeg.so' failed
  
  make: *** [/cygdrive/D/RAJESH-ANDROID/Rajesh-workspace/FFMPEG_2/libs/armeabi-v7a/libffmpeg.so] Error 1

  Can any one please explain why i am getting that permission denied issue and how to overcome that . i am using windows 7 pc.

  Thanks.
  Rajesh K

• FFMpeg on Android not working

  30 août 2013, par user2171513

  I have build FFmpeg statically linked binary and I am using it to do some video/audio encoding -decoding in an Android application. If I use FFmpeg from my android application using

  Runtime.getRuntime().exec(Command);

  then it seems to suddenly crash in between without any error logs.
  but If I run the exact same command through adb shell then it succeeds. I am not able to figure out what would be the difference in running a native binary through adb shell or through an Android Application.

  Any help is appreciated.