What's a good bitrate for TV quality MPG encoding?

[coolfish]

After capturing a show offa the TV, what's the best settings to keep the best quality/file size ratio? MPEG1 / mpeg 2 / NTSC VCD ? how many kb per second? 2048? 1123 ? Anyone find the "optimum" settings?

Coolfish

[This_Idiot]

Coolfish,

I know it's great to get tips straight off those that know. But that shouldn't stop anyone from doing there own research first - it doesn't even have to take very long to grab a 15 second clip under different sizes/rates/codecs and then render them back out. And those tests will be far more relevant to you than someone elses using a completely different setup halfway across the world.

Sorry Bud, not getting at you personally - But I really wish folks would actually read and try some before asking, ya know ?

[pederbc]

If yuo're making a VCD the bitrate is fixed, according to the specs at 1150 Kb/s. As someone else in this forum mentioned it's possible to go up to 2100 using the NERO burning. I've tried this and get a very good picture but the sound is totally screwed up. This has probably to do with the type of player you're using. In my case a Philips 730. If you're only going to play it on the PC, then you can normally use any bitrate you like. Like "This_Idiot" said, make a small clip and test with the lowest possible bitrate that you can accept. Low bitrate=less space & less quality, high bitrate= more space & better quality! Test, test, test...

[coolfish]

thisidiot - yeah, i know, i've been doing that as well. But i find that i usually manage to miss one important thing that makes a super Big Difference and that I would have taken years to figure out.


coolfish

[Walrus]

Coolfish:
As the others have pointed out, there is no optimal setting. It's all a matter of preference. However, two things to keep in mind is that image quality is not soley defined by compression type and data-rate. The more overlooked factors are source quality and motion estimation. You can severely improve source quality by using denoising filters on your file before you compress it, and to help reduce blockiness use the highest motion estimation settings available. Both of these make the processing longer, but the end result looks better and at lower data rates.
I usually end up archiving most material in VCD format since it's small and pretty universal. As long as I spend some time pre-processing the files, I usually end up with results that are perfectly fine for my purposes.

[coolfish]

AHa! filters, yeah this is something i've been wondering about.. My TV tuner isn't exaclty superfantastic quality, in fact, i'd wager to say it sucks (split about.. eleventeen times). What are the good noise filters in MSp6? What's this motion estimation ? I'll definately start looking for those then..

coolfish

[Walrus]

Coolfish: I'm afraid I can't tell you the filters to use in MSP6 since I don't have a copy, but generally you want to attack noise in two ways... a spatial denoiser and a temporal denoiser.
As for motion estimation, if memory serves there is a way of making MSP6 show all settings for mpeg encoding. (search the forums to find out the hack). If so, then set all of the motion vectors to 64. It will take longer to encode, but it allows the encoder to better figure out the motion which will reduce blockiness in fast moving sequences.

[This message has been edited by Walrus (edited 01 April 2000).]