[FFmpeg-user] Transcoding Infrastructure of Youtube

[s00b4u .]

Hi,

I recently came to know that Youtube uses FFMPEG (http://www.streaminglearningcenter.com/blogs/youtube-uses-ffmpeg-for-encoding.html) for their transcoding
requirements. I was wondering if someone knows about their
Infrastructure. I obviously am not asking for their company secrets. I
am just curious about the scale of Infrastructure which is involved. As
we all know that they have such a huge volume of media being transcoded all the
time, how many servers do they have? Do they use same version of FFMPEG
which is publically available or they have further optimized versions developed internally? 

If anyone knows, please share the knowledge.

Thanks.