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• Compiling FFmpeg staticly using NDK error - Not position independent executable

  27 février 2017, par David Barishev

  I have been trying to compile ffmpeg into a static library in order to use it in my android application, but i couldn’t get it to work.

  Im working with FFmpeg 3.2.4, and ndk r13b, using bash on windows 10(Ubuntu 14.04).

  Here is what i did :

  • I made a stand alone toolchain for x86_64 and api 21 using :
    python make_standalone_toolchain.py --api 21 --arch x86_64 --install-dir {}

  • Made a configuration script :

    ./configure \
    
    --target-os=android                                     \
    
    --arch=x86_64                                              \
    
    --prefix=/home/david/ffmpeg_x86_64_build                          \
    
    --cross-prefix=/home/david/x86_64_toolchain/bin/x86_64-linux-android-\
    
    --sysroot=/home/david/x86_64_toolchain/sysroot                    \
    
    --enable-cross-compile                                  \
    
    --pkg-config-flags="--static"                           \
    
    --enable-ffmpeg                                         \
    
    --disable-ffplay                                        \
    
    --disable-ffprobe                                       \
    
    --disable-ffserver                                      \
    
    --disable-doc                                           \
    
    --disable-htmlpages                                     \
    
    --disable-manpages                                      \
    
    --disable-podpages                                      \
    
    --disable-txtpages                                      \
    
    --extra-cflags="-fPIC"                                  \
    
    --extra-cxxflags="-fPIC"
    
    --disable-shared --enable-static \
    
    --enable-yasm
    
    
    
    make
    
    make install

  It produced an FFmpeg executable, however when i ran it on my API 23 emulator, i got an error message :error: only position independent executables (PIE) are supported.
  Even that i used -fPic

  How can i fix it ? Also i’m not sure about my configuration, there wasn’t up to date sources on how to compile it correctly for every ABI (arm,arm64,x86,x86_64,mips,mips64) that i need for my application.
  I have seen many script, and im not too familiar with compiling native code, so i wasn’t sure what settings i need, for example like C flags and etc.

  To be precise on how i tried to configure FFmpeg :

  • I need a static library
  • I Only need the ffmpeg command line utility
  • I want to compile the library for every ABI i listed above.This configuration tried to compile for x86_64.
  • Running on android of course

  I would greatly appreciate some help on how to configure and compile this correctly.

• FFMPEG - Overlay WebM over PNG Start Position

  26 avril 2022, par joshuaalvarez

  I am trying to place WebM videos over PNGs layered on top of each other. I have successfully done so, however, the WebM videos are not present in the first frame in the video and are added one frame at a time. For example, if I place 2 WebM videos over a PNG, it will layer one WebM per frame at a time.

  


  It may be important to note that I am using PNGs and WebMs as the inputs (WebM to use alpha channel) and exporting as MP4.

  


  I am using complex filters and the overlay in this way : overlay=format=auto per image/video.

  


  Here is a link to a MP4 that shows my issue. See how there is only the PNG portion in the video at 0:00 and the WebM portions come in shortly after.

  


• Revision 5e5d4c0ea7 : Enable reference frame masking for rt mode Reference frame masking helped good

  13 janvier 2014, par Yaowu Xu

  Changed Paths :
   Modify /vp9/encoder/vp9_onyx_if.c

  
  
  Enable reference frame masking for rt mode

  Reference frame masking helped good quality mode to gain about 5% in
  encoding speed, this commit enable it for rt mode to gain the speed
  improvement.

  In addition, this commit move the speed feature setup to a separate
  function.

  Change-Id : I015e8f78bbb21dd43ae183b9b9355bea2ccda9c5