At what point do you notice lost quality when lowering bitrate?

Robert M Wright · December 23rd, 2009, 05:52 PM

...and if the 135 minute version is a bit weak (image quality wise, due to compression), definitely apply visually lossless denoising before altering the editing, if changing the transitions would weaken the presentation at all.

Jeff Harper · December 23rd, 2009, 08:18 PM

Actually, it looks great. Since I reduced the auto gain on my camera, even dark footage looks relatively crisp, it's amazing...I'm liking my FX1000 more and more.

Josh Bass · December 24th, 2009, 08:04 AM

Can't VBR encoding cause problems for DVD players? A while ago, I used to have problems with several of my short films on DVD in many different players where the movie would stop, stutter, etc., but only in spots where it went from black to something else quickly, like a fade up of credits, fade up of picture, cutting to black and then cutting to picture, etc.

I bought new discs from Taiyo Yuden, tried all kinds of crap. Finally, someone on this board mentioned trying a constrained bit rate. BINGO! Haven't had this problem since.

That's my cautionary tale.

Robert M Wright · December 24th, 2009, 11:44 AM

Most likely the encoding settings were not within DVD video specs, or were pushing the edge of the specs (as mentioned above). Certainly, cap the peak video bitrate at 8000Kbps if you are having playback problems at all.

What encoder were you using?

Marty Welk · December 24th, 2009, 01:29 PM

Quote:

Originally Posted by Josh Bass

Can't VBR encoding cause problems for DVD players?.

Some Cheaper DVD players cant keep up with the data rate when it hits the high data rates, i purposfully have cheap dvd players to check , and exactally like Robert M Wright said, if you keep the max under 8000 most of them will handle it.
when i go over 8000 for a SHORT dvd i always supply a "compatability" track on the same dvd. and after testing we put the compatability track at First, they have to go to the second page to get the high data track.

Josh Bass · December 24th, 2009, 03:28 PM

Oh, geez, no idea. It was so long ago. I've been doing a CBR at 7K or below from that point on, though.

Yes, I had heard it was the reader/laser/DVD fairy having to go from reading black to reading full moving pixel changing craziness instantly that would "crash" it. It happened A LOT. I'm struggling to remember if there was ever a player I tried those discs on where it didn't happen.

Robert M Wright · December 24th, 2009, 05:14 PM

Did it crash with more than one player?

Josh Bass · December 24th, 2009, 05:41 PM

I think it only DIDN'T crash in one player. Almost every time I played those anywhere they had problems.

Robert M Wright · December 24th, 2009, 05:59 PM

My only guess is that you were probably using what I think of as an ultra-consumerish junk video editing package, like Pinnacle Studio, CyberLink PowerProducer, etc. I can well imagine one of those apps generating improper VBR encodings, at default settings no less, for DVD video - just wouldn't surprise me a bit.

Prech Marton · January 9th, 2010, 08:19 AM

hi guys,
i also make my wedding videos in CBR (maximum 6600kbps, 1.5 hour / disc)
i also hear that with VBR encoding fade in from black may be problematic, and may
have more compression artifact than with CBR. But honestly i didn't make a test.
So far every of my weddings fitted on two disc (2x1.5 hour)
But i like MPEG smart rendering in Vegas8, sometimes i need another edit, but i have only the rendered mpeg file. I ask, if i use VBR encoding, smart rendering will be still available, and work correctly? What is important? The min. average and max bitrate will be the same as in the original mpeg, or the whole thing work only with CBR?

thx

Graham Bernard · January 9th, 2010, 12:31 PM

What would be really cute would be to have some form of utility that would map out the noise in some 2 hour linear graph. This would then narrow one's attention/focus on the noisier sections.

Noise is painful for MPEG encoders. Actually not for the encoders, but for the playback device having to deal with it. Definitely reduce gain in camera; use a small bit of smoothing on nosier stuff; coventrate on dissolves that MAY have real movement within and unless needed, keep under 7mbs. If you CAN get away with 8mbs, great.

Grazie

December 24th, 2009, 08:04 AM	#18
Josh Bass Slash Rules! Join Date: Apr 2002 Location: Houston, Texas Posts: 5,472	Can't VBR encoding cause problems for DVD players? A while ago, I used to have problems with several of my short films on DVD in many different players where the movie would stop, stutter, etc., but only in spots where it went from black to something else quickly, like a fade up of credits, fade up of picture, cutting to black and then cutting to picture, etc. I bought new discs from Taiyo Yuden, tried all kinds of crap. Finally, someone on this board mentioned trying a constrained bit rate. BINGO! Haven't had this problem since. That's my cautionary tale. __________________ The Bass' camerawork The Bass on IMDB

December 24th, 2009, 03:28 PM	#21
Josh Bass Slash Rules! Join Date: Apr 2002 Location: Houston, Texas Posts: 5,472	Oh, geez, no idea. It was so long ago. I've been doing a CBR at 7K or below from that point on, though. Yes, I had heard it was the reader/laser/DVD fairy having to go from reading black to reading full moving pixel changing craziness instantly that would "crash" it. It happened A LOT. I'm struggling to remember if there was ever a player I tried those discs on where it didn't happen. __________________ The Bass' camerawork The Bass on IMDB

December 24th, 2009, 05:41 PM	#23
Josh Bass Slash Rules! Join Date: Apr 2002 Location: Houston, Texas Posts: 5,472	I think it only DIDN'T crash in one player. Almost every time I played those anywhere they had problems. __________________ The Bass' camerawork The Bass on IMDB

January 9th, 2010, 08:19 AM	#25
Prech Marton Major Player Join Date: May 2004 Location: hungary Posts: 462	hi guys, i also make my wedding videos in CBR (maximum 6600kbps, 1.5 hour / disc) i also hear that with VBR encoding fade in from black may be problematic, and may have more compression artifact than with CBR. But honestly i didn't make a test. So far every of my weddings fitted on two disc (2x1.5 hour) But i like MPEG smart rendering in Vegas8, sometimes i need another edit, but i have only the rendered mpeg file. I ask, if i use VBR encoding, smart rendering will be still available, and work correctly? What is important? The min. average and max bitrate will be the same as in the original mpeg, or the whole thing work only with CBR? thx __________________ Relaxing clips with waterfalls and music, 3D photos, 3D videos: www.3d-video.hu

December 23rd, 2009, 05:52 PM	#16
Robert M Wright Inner Circle Join Date: Jan 2006 Location: Minnesota (USA) Posts: 2,171	...and if the 135 minute version is a bit weak (image quality wise, due to compression), definitely apply visually lossless denoising before altering the editing, if changing the transitions would weaken the presentation at all.

December 23rd, 2009, 08:18 PM	#17
Jeff Harper Inner Circle Join Date: Jun 2005 Location: Cincinnati, OH Posts: 8,425	Actually, it looks great. Since I reduced the auto gain on my camera, even dark footage looks relatively crisp, it's amazing...I'm liking my FX1000 more and more.

December 24th, 2009, 11:44 AM	#19
Robert M Wright Inner Circle Join Date: Jan 2006 Location: Minnesota (USA) Posts: 2,171	Most likely the encoding settings were not within DVD video specs, or were pushing the edge of the specs (as mentioned above). Certainly, cap the peak video bitrate at 8000Kbps if you are having playback problems at all. What encoder were you using?

December 24th, 2009, 05:14 PM	#22
Robert M Wright Inner Circle Join Date: Jan 2006 Location: Minnesota (USA) Posts: 2,171	Did it crash with more than one player?

December 24th, 2009, 05:59 PM	#24
Robert M Wright Inner Circle Join Date: Jan 2006 Location: Minnesota (USA) Posts: 2,171	My only guess is that you were probably using what I think of as an ultra-consumerish junk video editing package, like Pinnacle Studio, CyberLink PowerProducer, etc. I can well imagine one of those apps generating improper VBR encodings, at default settings no less, for DVD video - just wouldn't surprise me a bit.

January 9th, 2010, 12:31 PM	#26
Graham Bernard Old Boot Join Date: Aug 2002 Location: London UK Posts: 3,633	What would be really cute would be to have some form of utility that would map out the noise in some 2 hour linear graph. This would then narrow one's attention/focus on the noisier sections. Noise is painful for MPEG encoders. Actually not for the encoders, but for the playback device having to deal with it. Definitely reduce gain in camera; use a small bit of smoothing on nosier stuff; coventrate on dissolves that MAY have real movement within and unless needed, keep under 7mbs. If you CAN get away with 8mbs, great. Grazie