Help/suggestions with bitrate.

Barney1 · Post by **Barney1** » Thu Apr 10, 2008 5:32 pm

Currently my video is 2 hours and 15 minutes long. I have the custom bitrate set to 8000.
The video source is a snowmobiling trip shot with a Sony Mini DV using a helmut cam. At 8000 I noticed that there are some artifacts in the snow when riding through the woods. Its not that bad, but I do notice it on my 65¡¨ RPTV. I no longer have the camera so I can¡¦t run the orginal lossless tape to the RPTV to see if I notice it there. I do now have a Canon mini HDDV camera, I guess I can use, but am not sure if you can play tapes on one camcorder when created from another. Anyway my next step is to do a test and remove about a ½ hours worth of video and bump the bitrate up to around 9300 based on the bitrate calculator floating around this site. I¡¦m just wondering if I will even notice a difference and that the source is what it is. Any input from the experts would be appreciated. Just so you know I am using a dual layer DVD (Verbatim). I am creating a DVD folder only and then using 1 Click DVD copy to burn the dual layer disk since it does a better job on DL than VS.

Post by **Ron P.** » Thu Apr 10, 2008 5:40 pm

Barney,

You might have a look at the following posts. Terry Stetler describes setting the GOP (Group of Pictures) to get better quality..

http://phpbb.ulead.com.tw/EN/viewtopic. ... 9645#49645

http://phpbb.ulead.com.tw/EN/viewtopic. ... 6513#26513

Barney1 · Post by **Barney1** » Thu Apr 10, 2008 11:56 pm

Videoman,

I have vista using VS and I added the advance=1 and I don't see any special new button to turn this on. Can you elaborate?

Barney1 · Post by **Barney1** » Fri Apr 11, 2008 4:19 am

videoman,

Well I bumped up the bitrate to 9400 and there was no difference. I got the advance=1 setting finally working to turn on the mpeg advance button. I tried Terry¡¦s settings but for some reason it doesn¡¦t save them. Two reason, when I go back in its back to the same settings before I changed them and when I do change them especially Terry¡¦s suggestion on GOP it did not increase the file size. Do you know if anybody else has come across this? I did install on an XP machine and same problem. Thanks in advance!

Post by **Ken Berry** » Fri Apr 11, 2008 4:34 am

It is of course possible (highly likely?) that the artifacts are a product of the helmet camera. As you would probably be aware, in normal circumstances, mini DV is pretty high quality, and such artifacts would not normally exist. But once there on the original tape (which I acknowledge you no longer have), there is little you can do about them. Certainly upping the bitrate is not going to improve things if the artifacts are already embedded, so to speak. And playing them back on a huge screen is of course going to highly magnify even the smallest defects...

In fact upping the bitrate as you are doing is getting into potentially dangerous territory for a standard video DVD. Many stand-alone DVD players have difficulty playing back standard DVDs with a video bitrate much over 8000 kbps. In addition, with a bitrate in the 9300 or 9400 kbps range you are getting perilously close to the top limit combined video/audio bitrate of 10,000 kbps...

Barney1 · Post by **Barney1** » Fri Apr 11, 2008 4:51 am

Ken,

I still do have the tapes, and I have the raw .avi files on my computer. When I play the .avi file on the computer I don¡¦t see the artifacts. When I play the DVD w/ bitrate @8000 I do see the artifacts. So I¡¦m seeing it on the PC as well as the big screen. I¡¦m trying to get Terry¡¦s advance options a try with a bitrate of 8000, but for some reason its not changing when I exit the mpeg settings because of the two reasons I mentioned above. I guess I will have to keep trying. Is the .ini file change to get the advance button turned on a hit or miss since the manual does not mention anything about it?

Post by **Ken Berry** » Fri Apr 11, 2008 5:11 am

It isn't meant to be 'hit and miss'. It's not mentioned in the manual, I suspect, because they don't want inexperienced users fiddling with the innards ... er ... ini's and possibly screwing up the program...

Barney1 · Post by **Barney1** » Fri Apr 11, 2008 5:24 am

Well, you may be right, but from my searches it sounds like people have gotten to work including Terry. The problem is that they seem to have made it work on XP not Vista. Based on Terry's instructions it pretty basic. I have a PM into him maybe he can shed some light. Thanks for your help!

Post by **Ken Berry** » Fri Apr 11, 2008 5:47 am

If you hear back from him, it might be good if you posted his response back here. And come to think of it, I have not even tried it on my new Vista machine, but had it working successfully on the old computer with XP...

Barney1 · Post by **Barney1** » Fri Apr 11, 2008 2:30 pm

Ken Berry wrote:If you hear back from him, it might be good if you posted his response back here. And come to think of it, I have not even tried it on my new Vista machine, but had it working successfully on the old computer with XP...

Will do. The advance option seems like a great tool if I can only get it to work in Vista! I would love to see if it helps out my video quality.

WestbrookNH · Post by **WestbrookNH** » Fri Apr 11, 2008 3:49 pm

There appears to be a "sweet spot" bit rate for the stuff I do, mostly photo slideshows with music.

6000 Kb VBR has been giving me better renderings and results than 8000.

Transitions, pans, and zooms appear to be smoother, and there appears to be more headroom for the music track (less distortion and better dynamic range).

skier-hughes · Post by **skier-hughes** » Fri Apr 11, 2008 4:57 pm

Most helmet cams only produce a low res image, some down to half that of dv.
So, as already mentioned this may be some of the cause.

To test, first try the original tape in yor new cam, if recorded in SP it may well play it.

If not, and assuming you captured as a dv.avi file, try outputing that dv.avi file back out to a cam. Hopefully your new one will have dv-in so you could record it in sd to that cam.

Then play this on your large tv.

If you didn't capture as dv.avi, then this may be part of the problem.

Barney1 · Post by **Barney1** » Fri Apr 11, 2008 6:26 pm

Graham,
I did capture from my original Mini DV camera as a .avi so I¡¦m good to go there. I took a chance and played the original mini DV tapes created on the Sony and played them back to my RPTV using the new HD Canon and there was no artifacts. I¡¦m guessing I will just have to play around with the bitrate to get it right. I do understand there is going to be some compress going from .avi to mpeg, but I¡¦m just trying to find that setting that will get me the best. I¡¦m making copies for about 10 people so you can see how I would like to get it just right. I can try the 6000 that westbrook suggested as well. Just hoping I can get the advance to work maybe there is something there that may help. Thanks for your input I will keep trying.

Barney1 · Post by **Barney1** » Sat Apr 12, 2008 1:01 am

Well, 6000 bitrate does not work too well. Hopefully I will here something from Terry on how to get the advance button to work in Vista or anybody else for that matter.

skier-hughes · Post by **skier-hughes** » Sat Apr 12, 2008 11:59 am

Good to know the original is good quality.
Are we still working with a 2 hour 15 min movie?
How about testing small amounts of it, pick some bits that show the artefacts and make a small movie and burnt o an RW disc.
Has your dvd player played DL discs well before, or is this a first?
Try an SL disc.

Alludo USER to USER Web Board

Help/suggestions with bitrate.

Help/suggestions with bitrate.

Lower bit rate might actually help