Sur d’autres sites (8160)

• Error : build_android.sh in #make

  25 juillet 2018, par 유재언

  License: LGPL version 2.1 or later
  
  Creating config.mak, config.h, and doc/config.texi...
  
  
  
  
  
  WARNING: c:/Designer_El_boy/ndk-bundle/toolchains/arm-linux-androideabi-4.9/prebuilt/windows-x86_64/bin/arm-linux-androideabi-pkg-config not found, 

  after ./build_android.sh, I proceed to make process.

  I followed this websibe. http://gamdekong.tistory.com/103?category=776642

  In file included from libavfilter/aeval.c:26:0:
  
  ./libavutil/avassert.h:30:20: fatal error: stdlib.h: No such file or directory
  
   #include 
  
                  ^
  
  compilation terminated.
  
  make: *** [common.mak:60: libavfilter/aeval.o] 오류 1

• Why this shell command doesn't work ? ('command' works but 'command|cat' doesn't work)

  16 octobre 2018, par yabee

  Problem

  The following code outputs like...

  $ ffprobe -show_frames -select_streams v test.mp4 2>/dev/null|grep -A 2 key_frame=1
  
  key_frame=1
  
  pkt_pts=0
  
  pkt_pts_time=0:00:00.000000
  
  --
  
  key_frame=1
  
  pkt_pts=41041
  
  pkt_pts_time=0:00:01.710042
  
  --
  
  key_frame=1
  
  pkt_pts=64064
  
  pkt_pts_time=0:00:02.669333
  
  --
  
  key_frame=1
  
  pkt_pts=87087
  
  pkt_pts_time=0:00:03.628625
  
  --
  
  ...

  But the folowing one outputs nothing.

  $ ffprobe -show_frames -select_streams v test.mp4 2>/dev/null|grep -A 2 key_frame=1|cat

  And...

  $ ffprobe -show_frames -select_streams v test.mp4 2>/dev/null|grep key_frame=1
  
  key_frame=1
  
  key_frame=1
  
  key_frame=1
  
  key_frame=1
  
  $ ffprobe -show_frames -select_streams v test.mp4 2>/dev/null|grep key_frame=1|cat
  
  # Nothing outputted.

  Why ?

  Expected result

  What actually I want to do is

  $ ffprobe -show_frames -select_streams v test.mp4 2>/dev/null|grep -A 2key_frame=1|grep time
  
  pkt_pts_time=0:00:00.000000
  
  pkt_pts_time=0:00:01.710042
  
  pkt_pts_time=0:00:02.669333
  
  pkt_pts_time=0:00:03.628625
  
  ...

  But its result is

  $ ffprobe -show_frames -select_streams v test.mp4 2>/dev/null|grep -A 2key_frame=1|grep time
  
  # Nothing outputted.

  Grep works correctory exept it’s after ffprobe.

  $ seq 30|grep 1|grep 2
  
  12
  
  21

  Environment

  • Bash on Ubuntu on Windows 10 Pro
    • Windows version : 1803
    • Windows OS build : 17134.345

  Environment of Ubuntu :

  $ cat /etc/lsb-release
  
  DISTRIB_ID=Ubuntu
  
  DISTRIB_RELEASE=18.04
  
  DISTRIB_CODENAME=bionic
  
  DISTRIB_DESCRIPTION="Ubuntu 18.04.1 LTS"
  
  
  
  $ bash --version
  
  GNU bash, version 4.4.19(1)-release (x86_64-pc-linux-gnu)
  
  Copyright (C) 2016 Free Software Foundation, Inc.
  
  License GPLv3+: GNU GPL version 3 or later /gnu.org/licenses/gpl.html>
  
  
  
  This is free software; you are free to change and redistribute it.
  
  There is NO WARRANTY, to the extent permitted by law.
  
  
  
  $ ffprobe
  
  ffprobe version 3.4.4-0ubuntu0.18.04.1 Copyright (c) 2007-2018 the FFmpeg developers
  
    built with gcc 7 (Ubuntu 7.3.0-16ubuntu3)
  
    configuration: --prefix=/usr --extra-version=0ubuntu0.18.04.1 --toolchain=hardened --libdir=/usr/lib/x86_64-linux-gnu --incdir=/usr/include/x86_64-linux-gnu --enable-gpl --disable-stripping --enable-avresample --enable-avisynth --enable-gnutls --enable-ladspa --enable-libass --enable-libbluray --enable-libbs2b --enable-libcaca --enable-libcdio --enable-libflite --enable-libfontconfig --enable-libfreetype --enable-libfribidi --enable-libgme --enable-libgsm --enable-libmp3lame --enable-libmysofa --enable-libopenjpeg --enable-libopenmpt --enable-libopus --enable-libpulse --enable-librubberband --enable-librsvg --enable-libshine --enable-libsnappy --enable-libsoxr --enable-libspeex --enable-libssh --enable-libtheora --enable-libtwolame --enable-libvorbis --enable-libvpx --enable-libwavpack --enable-libwebp --enable-libx265 --enable-libxml2 --enable-libxvid --enable-libzmq --enable-libzvbi --enable-omx --enable-openal --enable-opengl --enable-sdl2 --enable-libdc1394 --enable-libdrm --enable-libiec61883 --enable-chromaprint --enable-frei0r --enable-libopencv --enable-libx264 --enable-shared
  
    libavutil      55. 78.100 / 55. 78.100
  
    libavcodec     57.107.100 / 57.107.100
  
    libavformat    57. 83.100 / 57. 83.100
  
    libavdevice    57. 10.100 / 57. 10.100
  
    libavfilter     6.107.100 /  6.107.100
  
    libavresample   3.  7.  0 /  3.  7.  0
  
    libswscale      4.  8.100 /  4.  8.100
  
    libswresample   2.  9.100 /  2.  9.100
  
    libpostproc    54.  7.100 / 54.  7.100
  
  Simple multimedia streams analyzer
  
  usage: ffprobe [OPTIONS] [INPUT_FILE]
  
  
  
  You have to specify one input file.
  
  Use -h to get full help or, even better, run 'man ffprobe'.

  What is problem ?

  Does grep or ffprobe change its behavior by existence of pipe in this case ?
  Thanks.

• FFmpeg AVFrame to OpenGL texture without YUV to RGB soft conversion

  15 novembre 2018, par zebeurton

  I want to decode an encrypted H264 video file on iOS. I already have ported our decryption algorithm and it is working fine. However, we cannot directly use H264 hardware decoder due to lack of API in SDK.

  So I am trying to find an alternative to decode H264 video. I am trying to use FFmpeg to decode these video even if there are some possible LGPL license issues. I decode H264 video without any problems and I render H264 frames thanks to OpenGL ES texture. But there are some performance issues. I instrumented my code and the bottleneck is the ffmpeg rescaling and YUV to RGB conversion.
  I know that I can use OpenGL ES 2.0 shaders to convert YUV to RGB with GPU acceleration (related post Alternative to ffmpeg for iOS).
  I also know how AVFrame structure is composed : data[0] for Y data, data[1] for U data and data[1] for V data. But I do not understand how can I use line size[x] with data[x] to transmit data to OpenGL texture.

  Does anybody have an example of AVFrame YUV to OpenGL texture ?

  Thanks,
  David