Monday, February 25, 2008

Beauty In The Eye Of The Beholder

The poor quality of encoding on the BBC iPlayer has sent me back to take a look at what works best in trying to optimise video quality.

Quality is always a subjective measure, but the variances on online service do separate out web video sites from internet TV channels more than anything. Spending a reported £20m + and ending up with blurryvision really isn't acceptable in my book.

For those of you without big budgets there's a great overview of the software available out there here.

There are also more expensive, professional options available from companies like Anystream.

The quality of the video is always going to be a trade-off between the time spent encoding and the desired output. The longer the encoding takes, the better the output tends to be. In order to improve this trade off you can invest heavily in hardware encoding and acceleration.

Companies such as Digital Rapids, Optibase, Telestream, VBrick and ViewCast all offer hardware options.

There are a few key factors, however, which are worth looking at more closely:

1) The codec - I still firmly believe that, of the freely available codecs, Microsoft's VC-1 is still best

2) Encoding package - some of my colleagues swear by Microsoft's free Windows Media Encoder, but Narrowstep always used and recommended Autodesk Cleaner, with results that speak for themselves.

3) The source - it's rubbish in, worse rubbish out; even at low data rates you can tell content sourced on HD - always use the best source content available and always film in HD

3) Settings - getting the size (resolution), data rate, pass, keyframes, etc right is an art that's learned, not something that can be bought in a box.

Interestingly enough, the power of the hardware platform seems to make minimal difference either to the quality or, surprisingly, to the encoding time. Still, slower is better.

1 comment:

donnierules said...

Winnov is another maker of video encoding hardware. They make some of the best capture cards out there, but people don't really know about them.
www.winnov.com