Newest 'libx264' Questions - Stack Overflow

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• How to resolve "ERROR : libx264 not found" ?

  16 mars 2016, par user3665376

  I needed to install ffmpeg with libx264 support for enabling H.264 encoding . I installed libx264 successfully using the below script with toolchains available in android-ndk-r9d .

   #!/bin/bash
   NDK=~/android-ndk-r9d
   SYSROOT=$NDK/platforms/android-8/arch-arm/
   TOOLCHAIN=$NDK/toolchains/arm-linux-androideabi-4.6/prebuilt/linux-x86_64
   function build_one
   {
   ./configure \
   --cross-prefix=$TOOLCHAIN/bin/arm-linux-androideabi- \
   --sysroot="$SYSROOT" \
   --host=arm-linux \
   --enable-pic \
   --enable-shared \
   --disable-cli
   make clean
   make
   make install
   }
   build_one 
  

  Now I wanted to build ffmpeg with libx264 support . I used the below script with --enable-libx264 , --enable-nonfree , --enable-gpl options as in the below script .

  #!/bin/bash
  NDK=~/android-ndk-r9d
  SYSROOT=$NDK/platforms/android-8/arch-arm/
  TOOLCHAIN=$NDK/toolchains/arm-linux-androideabi-4.6/prebuilt/linux-x86_64
  function build_one
  {
  ./configure \
  --prefix=$PREFIX \
  --enable-shared \
  --enable-nonfree \
  --enable-gpl \
  --enable-libx264 \
  --disable-doc \
  --disable-ffmpeg \
  --disable-ffplay \
  --disable-ffprobe \
  --disable-ffserver \
  --disable-avdevice \
  --disable-doc \
  --disable-symver \
  --cross-prefix=$TOOLCHAIN/bin/arm-linux-androideabi- \
  --target-os=linux \
  --arch=arm \
  --enable-cross-compile \
  --sysroot=$SYSROOT \
  --extra-cflags="-Os -fpic $ADDI_CFLAGS" \
  --extra-ldflags="$ADDI_LDFLAGS" \
  $ADDITIONAL_CONFIGURE_FLAG
  make clean
  make
  make install
  }
  CPU=arm
  PREFIX=$(pwd)/android/$CPU
  ADDI_CFLAGS="-marm"
  build_one
  

  But when I run the script I'm getting error "ERROR: libx264 not found" .

  I suppose ffmpeg is not able to figure out the installed location of libx264 . After libx264 installation I have libx264.so file in /usr/local/lib executable at /usr/local/bin and header files at /usr/local/include directories .

  What all changes do I need to make to the ffmpeg build script in-order to make it detect libx264?

  Note : I am using Ubuntu 12.04(64 bit) for cross compiling .

• x264_encoder_encode() how to watch function body ?

  25 février 2016, par ULTRANj

  I'm working with VLC player source code (GitHub link) and I need to study how the function x264_encoder_encode() in codec h.264 works. This function is used in file x264.c but i couldn't find it's body and decloration. Where can I see it?

• ffmpeg weird x264 encoding behavior

  1er février 2016, par JMor

  I have a captured a 720x480 video with a display aspect ratio of 16:9 which I want to crop, resize and pad, but just the x264 encoding command is giving me a headache.

  (Screenshot of input.m2v) Here is my command:

  ffmpeg -ss 1861 -i input.m2v -c:v libx264 -profile:v main -preset:v medium -level 3.1 -x264opts crf=21.228 -t 60 -y -f mp4 output.mp4
  

  And here is the ffmpeg output:

  (Screen shot of output.mp4)

  Input #0, mpegvideo, from 'input.m2v':
    Duration: N/A, bitrate: N/A
      Stream #0:0: Video: mpeg2video (Main), yuv420p(tv), 720x480 [SAR 32:27 DAR 1
  6:9], max. 6605 kb/s, 31.02 fps, 59.94 tbr, 1200k tbn, 59.94 tbc
  [libx264 @ 02ba84c0] using SAR=32/27
  [libx264 @ 02ba84c0] using cpu capabilities: MMX2 SSE2Fast SSSE3 SSE4.2 AVX
  [libx264 @ 02ba84c0] profile Main, level 3.1
  [libx264 @ 02ba84c0] 264 - core 144 r2525 40bb568 - H.264/MPEG-4 AVC codec - Cop
  yleft 2003-2014 - http://www.videolan.org/x264.html - options: cabac=1 ref=3 deb
  lock=1:0:0 analyse=0x1:0x111 me=hex subme=7 psy=1 psy_rd=1.00:0.00 mixed_ref=1 m
  e_range=16 chroma_me=1 trellis=1 8x8dct=0 cqm=0 deadzone=21,11 fast_pskip=1 chro
  ma_qp_offset=-2 threads=12 lookahead_threads=2 sliced_threads=0 nr=0 decimate=1
  interlaced=0 bluray_compat=0 constrained_intra=0 bframes=3 b_pyramid=2 b_adapt=1
   b_bias=0 direct=1 weightb=1 open_gop=0 weightp=2 keyint=250 keyint_min=25 scene
  cut=40 intra_refresh=0 rc_lookahead=40 rc=crf mbtree=1 crf=21.2 qcomp=0.60 qpmin
  =0 qpmax=69 qpstep=4 ip_ratio=1.40 aq=1:1.00
  Output #0, mp4, to 'output.mp4':
    Metadata:
      encoder         : Lavf56.19.100
      Stream #0:0: Video: h264 (libx264) ([33][0][0][0] / 0x0021), yuv420p, 720x48
  0 [SAR 32:27 DAR 16:9], q=-1--1, 29.97 fps, 30k tbn, 29.97 tbc
      Metadata:
        encoder         : Lavc56.21.102 libx264
  Stream mapping:
    Stream #0:0 -> #0:0 (mpeg2video (native) -> h264 (libx264))
  

  The output size is 720x480, displayed as 853x480, as expected. But it looks like the frame has been vertically scaled by a factor of 1.18 and then cropped to a height of 480, so that I am losing the top and bottom of the frame. In fact, the behavior is equivalent to:

  -vf "scale=720:569,crop=720:480:0:0"
  

  Although I assume the aspect ratio plays a part here (I think the 1.18 factor is really (16/9)/(720/480)) I am surprised that ffmpeg would do that out of the blue. May be someone more knowledgeable than me could explain it?

• FFmpeg on android with libX264 and libfreetype

  1er février 2016, par LostPuppy

  I previously had a ffmpeg build with just the x264 library and now I have re-complied ffmpeg with x264 and libfreetype. I used the guardian project and used the following script

  #!/bin/bash
  
  . abi_settings.sh $1 $2 $3
  
  pushd ffmpeg
  
  case $1 in
    armeabi-v7a | armeabi-v7a-neon)
      CPU='cortex-a8'
    ;;
    x86)
      CPU='i686'
    ;;
  esac
  
  make clean
  
  ./configure \
  --target-os=linux \
  --arch=arm \
  --cross-prefix="$CROSS_PREFIX" \
  --cpu="$CPU" \
  --sysroot="$NDK_SYSROOT" \
  --enable-encoder=mpeg4 \
  --enable-pic \
  --enable-libx264 \
  --enable-libfreetype \
  --enable-pthreads \
  --enable-version3 \
  --enable-gpl \
  --disable-doc \
  --disable-shared \
  --enable-static \
  --pkg-config="${2}/ffmpeg-pkg-config" \
  --prefix="${2}/build/${1}" \
  --extra-cflags='-I/usr/local/include' \
  --extra-ldflags='-L/usr/local/lib'\
  
  make -j${NUMBER_OF_CORES} && make install || exit 1
  
  popd
  

  I am observing that the new build is taking almost double the time to process videos on android device when compared with previous versions.

  Any suggestions on speeding up the binary ?

• Why does FFMPEG insert frames in the beginning of a recoded video ?

  18 janvier 2016, par Filipe Costa

  I have a video with 300 frames. After type the following command, the resultant video has 302 frames.

  ffmpeg -y -i input.avi -vcodec libx264 -qscale 22 -qmin 22 -qmax 22 -an -g 13 output.avi

  The parameters of "input.avi" are: -vcodec libx264 -qscale 26 -qmin 26 -qmax 26 -an -g 8

  I did check the video and the first 3 frames are exactly the same.

  Why does it happen? Basically, I am trying to compare both videos "framewise" without any kind of temporal alignment.