CBR or VBR and Motion Detection

[Tolwyn]

Is there quality to be gained going VBR over CBR? For me, I use a higher CBR because it takes (understandably) twice as long to encode a stream VBR.

If I'm using CBR, does motion detection even play a part?

[ZippyP.]

VBR allows you to use a lower average bitrate so that you can keep the quality and reduce the file size. VBR is not any better than CBR with a high enough bitrate. What's high enough? That's for you to decide as it depends on the video and your eye. If disk space is not an issue then use CBR and crank up the bitrate.

Talking TMPGEnc, I use motion search estimate and can't tell any difference.

[jimmalenko]

Looks like a browse of the forums or a search or a google was a bit too much, eh ?


https://www.videohelp.com/forum/viewtopic.php?t=274197


I'm positive this has been discussed 1000's of times here before, and that you should be able to find dozens of links

[Tolwyn]

Yes, Jim.
But with the noise to signal ratio of false searches. How much time do YOU think is too much time wading through all those posts?

I'm not here to be a forum expert.
I'm not here to be a search expert.

[edDV]

Yes, Jim.
But with the noise to signal ratio of false searches. How much time do YOU think is too much time wading through all those posts?

I'm not here to be a forum expert.
I'm not here to be a search expert.

We will put in more effort for someone who has done the obvious grunt work.

Some additional suggestions.

Handheld (shakey) camcorder material is best at CBR max bitrate.
VBR - two pass will optimize a predicted file size (i.e. fit 4.35GB near exactly) at the cost of double time.

If I'm using CBR, does motion detection even play a part?

The MPeg encoder always uses "motion detection". Are you talking about a setting in your encoder?

[adam]

The motion detection setting does still play a part even with CBR encoding. Even with the bitrate constant per second, the whole way mpeg compression works is by distinguishing movement from static parts so that it only has to store redundant data once per GOP.

If you are using high bitrates then you probably won't see too much difference in motion detection settings regardless of whether you use VBR or CBR...but try doing a CBR encode once with highest and once with lowest motion detection and you will see a huge difference.

[adam]

I assume he's talking about the motion detection setting in TMPGenc. Like you said, its always something that encoders use. I think TMPGenc just lets you adjust its settings to offset its slow speed.

[Tolwyn]

By the way, I do search these forums regularly, but there's only so many lengths of pages of posts that I (or anyone) can be expected to wade through.

After ~20 minutes of searching, I think it's appropriate to risk reposting a question.

I was talking about motion detection; and I do notice a difference; especially when pausing content on the DVD player.

It seems "better" using a HIGH setting.

[edDV]

Backing off on motion detection will reduce sensitivity to noise being detected as motion thus allowing greater compression. Going too far will result in missing subtle motion.

[lenti_75]

usually is not a big difference if the bitrate is high enough, but it's better to use VBR, even if takes longer.

[Redd]

Looks like a browse of the forums or a search or a google was a bit too much, eh ?


https://www.videohelp.com/forum/viewtopic.php?t=274197


I'm positive this has been discussed 1000's of times here before, and that you should be able to find dozens of links

Watch out for jimmalenko, he's Captian of the forum patrol.
He's probable going to give you a sanction there Tolwyn. You're in big doodoo now.

[jimmalenko]

Watch out for Redd, he's just going to make some smart-ass comment and not contribute to helping you at all

Yes, Jim.
But with the noise to signal ratio of false searches. How much time do YOU think is too much time wading through all those posts?

I found 5 or 6 threads that were appropriate with my first search

I'm not here to be a forum expert.
I'm not here to be a search expert.

I'm not here to hold lazy people's johnsons for them. Free help is good help, so mention the fact that you've done some research prior and you'll get a lot more support

[Tolwyn]

Then you better close down the newbie forum. Kinda invites this type of stuff.

[jimmalenko]

Then you better close down the newbie forum. Kinda invites this type of stuff.

Ahhhhh no.

Remember those conditions you agreed to when you signed up here ?

https://www.videohelp.com/forum/viewtopic.php?t=124514

Please try to do some basic research before posting.
Most fundamental questions are answered on the How To's on this site.

Use the Forum search feature. Using the search can yield rich rewards as most questions have already been previously answered.

What makes you feel you that these don't apply for you ?

[Tolwyn]

You assume too much, my friend.
Prove that I didn't already try to search? Which I did, and I do, for the most part.

I'm not a forum search expert. How long would you like to argue this with me?

[jimmalenko]

nevermind.


I like the info given at LordSmurf's site:

http://www.digitalfaq.com/dvdguides/convert/tmpgenc/tmpgenc.htm

Motion Search Precision. Although many will argue about the meaning and the quality of output by using the various levels of Motion Search, this setting is not a direct determination of quality. Making it HIGH or HIGHEST will not increase quality, but rather control the instructions that tell the encoder how to produce the MPEG. An MPEG by its very nature is a motion-searched group of pictures. While the settings can AFFECT the quality of output, it will NOT determine it. But even these affects are limited in reach.

Searching motion for longer periods of time (HIGH and HIGHEST) generally make no difference in final output, especially when the bit-rate of the MPEG-2 is set at decent levels. Beyond those that attempt to squeeze many hours on a DVD (more than 3 hours) or attempt to convert large files to a single CD, these options have very little use.

For MPEG-2 DVD files, MOTION ESTIMATE provides excellent results without needlessly adding time to the encode.

For MPEG-1 VCD files, HIGH provides the level of search required for excellent results. Again, without adding unneeded time.

TMPGEnc has several problems with options, mostly due to its age and translation issues with the programmers. This setting is one of those problematic aspects of the software, because it really is not needed, at least not as it exists. Most encoders make these determinations based upon your desired output from the source. While some argue that this "takes away" you control, it simply makes the best decision without allowing room for error.

This setting would make more sense if it were labeled differently. It could easily make them into four settings: MPEG-2 DVD, MPEG-1 VCD, Mastering (HIGHEST) and Streaming (LOWEST). Mastering would only be used on DVD footage that has lots of high-impact, non-stop action (normally racing movies and sporting events only) and for those that insist on over-stretching the limitations of their media (the 6-hour DVD and 90-minute VCD scenario).

[Tolwyn]

Cool. Thanks for this information. Copy/Pasted into my cheat sheets/help guides. Heh.

[jimmalenko]

I think there's a couple of guides in the guides section that deal with "Configuring TMPGEnc for high-quality MPEG-2 output" as well, that are worth reading IMO ...

[Tolwyn]

I have the 3.x version of the software; I don't seem to have the ability to use Motion Estimate.

Just Low, Normal, High, High (error correction)

...This setting would make more sense if it were labeled differently. It could easily make them into four settings: MPEG-2 DVD, MPEG-1 VCD, Mastering (HIGHEST) and Streaming (LOWEST). Mastering would only be used on DVD footage that has lots of high-impact, non-stop action (normally racing movies and sporting events only) and for those that insist on over-stretching the limitations of their media (the 6-hour DVD and 90-minute VCD scenario).

[/quote]