ffmpeg woe

c:\dev\ruby\virtual-audio-output-sniffer>ffmpeg -f dshow -i audio="virtual-audio-capturer" captured_audio.mp3

FFmpeg version SVN-r23418, Copyright (c) 2000-2010 the FFmpeg developers

built on Jun 2 2010 04:12:01 with gcc 4.4.2

configuration: --target-os=mingw32 --enable-runtime-cpudetect --enable-avisynth --enable-gpl --enable-version3 --enable-bzlib --enable-libgsm --enable-libfaad --enable-pthreads --enable-libvorbis --enable-libtheora --enable-libspeex --enable-libmp3lame --enable-libopenjpeg --enable-libxvid --enable-libschroedinger --enable-libx264 --extra-libs='-lx264 -lpthread' --enable-libopencore_amrwb --enable-libopencore_amrnb --enable-librtmp --extra-libs='-lrtmp -lssl -lcrypto -lws2_32 -lgdi32 -lwinmm -lcrypt32 -lz' --arch=x86 --cross-prefix=i686-mingw32- --cc='ccache i686-mingw32-gcc' --enable-memalign-hack

libavutil 50.16. 0 / 50.16. 0

libavcodec 52.72. 1 / 52.72. 1

libavformat 52.67. 0 / 52.67. 0

libavdevice 52. 2. 0 / 52. 2. 0

libavfilter 1.20. 0 / 1.20. 0

libswscale 0.11. 0 / 0.11. 0

Unknown input format: 'dshow'

c:\dev\ruby\virtual-audio-output-sniffer>whichr ffmpeg

higher in the list is executed first

G:\Program Files (x86)\ImageMagick-6.7.1-Q16\ffmpeg.exe

c:\installs\ffmpeg.bat

c:\dev\ruby\virtual-audio-output-sniffer>whichr ffplay

higher in the list is executed first

c:\installs\ffplay.bat

meant "I was accidentally using a different version of ffmpeg--that bundled with imagemagick--instead of the one that does support installed in a different location"