ffmpeg -devices
ffmpeg version 3.4-d056a4c Copyright (c) 2000-2017 the FFmpeg developers
  built with gcc 7.2.0 (GCC)
  configuration: --prefix=/usr --cpu=cortex-a7 --arch=arm --enable-cross-compile --cross-prefix=/home/neil/projects/LibreELEC.tv/build.LibreELEC-RPi2.arm-9.0-devel/toolchain/bin/armv7ve-libreelec-linux-gnueabi- --sysroot=/home/neil/projects/LibreELEC.tv/build.LibreELEC-RPi2.arm-9.0-devel/toolchain/armv7ve-libreelec-linux-gnueabi/sysroot --sysinclude=/home/neil/projects/LibreELEC.tv/build.LibreELEC-RPi2.arm-9.0-devel/toolchain/armv7ve-libreelec-linux-gnueabi/sysroot/usr/include --target-os=linux --nm=/home/neil/projects/LibreELEC.tv/build.LibreELEC-RPi2.arm-9.0-devel/toolchain/bin/armv7ve-libreelec-linux-gnueabi-nm --ar=/home/neil/projects/LibreELEC.tv/build.LibreELEC-RPi2.arm-9.0-devel/toolchain/bin/armv7ve-libreelec-linux-gnueabi-ar --as=/home/neil/projects/LibreELEC.tv/build.LibreELEC-RPi2.arm-9.0-devel/toolchain/bin/armv7ve-libreelec-linux-gnueabi-gcc --cc=/home/neil/projects/LibreELEC.tv/build.LibreELEC-RPi2.arm-9.0-devel/toolchain/bin/armv7ve-libreelec-linux-gnueabi-gcc --ld=/home/neil/projects/LibreELEC.tv/build.LibreELEC-RPi2.arm-9.0-devel/toolchain/bin/armv7ve-libreelec-linux-gnueabi-gcc --host-cc=/home/neil/projects/LibreELEC.tv/build.LibreELEC-RPi2.arm-9.0-devel/toolchain/bin/host-gcc --host-cflags='-O2 -Wall -pipe -I/home/neil/projects/LibreELEC.tv/build.LibreELEC-RPi2.arm-9.0-devel/toolchain/include -Wno-format-security' --host-ldflags='-Wl,-rpath,/home/neil/projects/LibreELEC.tv/build.LibreELEC-RPi2.arm-9.0-devel/toolchain/lib -L/home/neil/projects/LibreELEC.tv/build.LibreELEC-RPi2.arm-9.0-devel/toolchain/lib' --extra-cflags='-I/home/neil/projects/LibreELEC.tv/build.LibreELEC-RPi2.arm-9.0-devel/toolchain/armv7ve-libreelec-linux-gnueabi/sysroot/usr/include/interface/vcos/pthreads -I/home/neil/projects/LibreELEC.tv/build.LibreELEC-RPi2.arm-9.0-devel/toolchain/armv7ve-libreelec-linux-gnueabi/sysroot/usr/include/interface/vmcs_host/linux -DRPI=1 -march=armv7ve -mabi=aapcs-linux -Wno-psabi -Wa,-mno-warn-deprecated -mcpu=cortex-a7 -mfloat-abi=hard -mfpu=neon-vfpv4 -fomit-frame-pointer -Wall -pipe -Os ' --extra-ldflags='-march=armv7ve -mtune=cortex-a7 -Wl,--as-needed ' --extra-libs='-lbcm_host -lvcos -lvchiq_arm -lmmal -lmmal_core -lmmal_util -lvcsm' --disable-static --enable-shared --enable-gpl --disable-version3 --enable-nonfree --enable-logging --disable-doc --disable-debug --enable-stripping --enable-pic --pkg-config=/home/neil/projects/LibreELEC.tv/build.LibreELEC-RPi2.arm-9.0-devel/toolchain/bin/pkg-config --enable-optimizations --disable-extra-warnings --disable-ffprobe --disable-ffplay --disable-ffserver --enable-ffmpeg --enable-avdevice --enable-avcodec --enable-avformat --enable-swscale --enable-postproc --enable-avfilter --disable-devices --enable-pthreads --disable-w32threads --enable-network --disable-gnutls --enable-openssl --disable-gray --enable-swscale-alpha --disable-small --enable-dct --enable-fft --enable-mdct --enable-rdft --disable-crystalhd --disable-vaapi --disable-vdpau --disable-dxva2 --enable-runtime-cpudetect --enable-hardcoded-tables --disable-encoders --enable-encoder=ac3 --enable-encoder=aac --enable-encoder=wmav2 --enable-encoder=mjpeg --enable-encoder=png --disable-decoder=mpeg_xvmc --enable-hwaccels --disable-muxers --enable-muxer=spdif --enable-muxer=adts --enable-muxer=asf --enable-muxer=ipod --enable-muxer=mpegts --enable-muxer=null --enable-encoder=libx264 --enable-encoder=libxvid --enable-encoder=mpeg4 --enable-encoder=mpeg2video --enable-demuxers --enable-parsers --enable-bsfs --enable-protocol=http --disable-indevs --disable-outdevs --enable-filters --disable-avisynth --enable-bzlib --disable-frei0r --disable-libopencore-amrnb --disable-libopencore-amrwb --disable-libopencv --disable-libdc1394 --disable-libfreetype --disable-libgsm --disable-libmp3lame --disable-libopenjpeg --disable-librtmp --enable-libspeex --disable-libtheora --disable-libvo-amrwbenc --disable-libvorbis --disable-libvpx --disable-libx264 --disable-libxavs --disable-libxvid --enable-zlib --enable-asm --disable-altivec --enable-neon --enable-yasm --disable-symver
  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
  libswscale      4.  8.100 /  4.  8.100
  libswresample   2.  9.100 /  2.  9.100
  libpostproc    54.  7.100 / 54.  7.100
Devices:
 D. = Demuxing supported
 .E = Muxing supported
 --