Why aren't software encode solutions better for ultimate quality?

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Here is a question for those that might know how encoding gets done by hardware chips (C-Cube, SigmaDesigns, Sony, etc):

If you get a software encoder that allows you to trade off time for quality, then theoretically I would assume the software solution to produce better results than hardware given enough time. So if I am willing to let Ligos LSX encoder chew on my data for overnight, won't it produce better results than a real-time hardware encode.

I'm assuming that for each hardware chip, there are bounds on how much image information it looks at, since it has a finite time slice to do all its calculations.

But the other possibility is: hardware encoders do as much as possible relative to what we can visualize, or no software encoder lets you tradeoff that much time for quality. Any thoughts on this?

-- Bill Katz (WTKatz@yahoo.com), February 29, 2000

Answers

As far as quality goes I've heard arguments from both sides of the camp as to which is better. One site actually claimed that software encoders were no doubt better and then went on to say later that you can't really tell the difference. I've tried both and I can't tell the difference. think the basic difference is cost. I had the Dazzle DVC at first, which is at the low end cost wise, and it was horrible. You have to shell out upwards of $600 to fined a decent hardware encoder.

-- Al McCraw (amccraw@ix.netcom.com), February 29, 2000.

The above statement is deffinitely true. I have an Adaptec Videoh! Parralel port capture device. Although it has an audio/video sync chip which allows me to capture for hours on end with no audio/video sync problems whatsoever, the quality is horrible on VCD capture settings. So I capture at 3mbps, then re-encode to VCD 2.0 compliant MPEG files using Panasonic encoder 2.3 (stand alone version). I use Pansonic Encoder's filtering effects and after it's done, the image looked better than when my friend encodes realtime with his Broadway.

However, I when I used Darim MPEGator and M-filter together, and did realtime encoding at VCD specs, result (from a laserdisc) was SVHS quality.

It all depends on what hardware you have and which way that you want to approach encoding, but rememer the golden rule of VCD'ing : trash in trash out.

-- MrVCD (mrvcd@juno.com), March 01, 2000.


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