Oh shoot I am getting Unknown encoder 'libx264' here is my output:
ffmpeg version 2.2.1 Copyright (c) 2000-2014 the FFmpeg developers
built on Jun 9 2014 20:01:41 with emcc (Emscripten GCC-like replacement) 1.12.0 (commit 6960d2296299e96d43e694806f5d35799ef8d39c)
configuration: --cc=emcc --prefix=/Users/bgrinstead/Sites/videoconverter.js/build/ffmpeg/../dist --enable-cross-compile --target-os=none --arch=x86_32 --cpu=generic --disable-ffplay --disable-ffprobe --disable-ffserver --disable-asm --disable-doc --disable-devices --disable-pthreads --disable-w32threads --disable-network --disable-hwaccels --disable-parsers --disable-bsfs --disable-debug --disable-protocols --disable-indevs --disable-outdevs --enable-protocol=file
libavutil 52. 66.100 / 52. 66.100
libavcodec 55. 52.102 / 55. 52.102
libavformat 55. 33.100 / 55. 33.100
libavdevice 55. 10.100 / 55. 10.100
libavfilter 4. 2.100 / 4. 2.100
libswscale 2. 5.102 / 2. 5.102
libswresample 0. 18.100 / 0. 18.100
[vp8 @ 0xdde460] Warning: not compiled with thread support, using thread emulation
Input #0, matroska,webm, from 'input.webm':
Metadata:
encoder : QTmuxingAppLibWebM-0.0.1
Duration: N/A, start: 0.000000, bitrate: N/A
Stream #0:0(eng): Video: vp8, yuv420p, 1920x1200, SAR 1:1 DAR 8:5, 30 fps, 30 tbr, 1k tbn, 1k tbc (default)
Unknown encoder 'libx264'
Ah shoot I use ffmpeg.js which has x264 here - https://github.com/bgrins/videoconverter.js/tree/master/build
But I don’t think it was compiled with it per here he says - http://bgrins.github.io/videoconverter.js/
Processing Additional Codecs
This isn't yet compiled with support for additional codecs
like zlib, x264, libvpx, etc. It should be possible to do.
Do you know of a non-libx264 command line method? Or are you familiar with ffmpeg.js?
Excuse that, I am just a browser extension developer making a screencast addon that converts to mp4 and gives to user to upload to twitter.