Video Looses Sharpness/Quality When Under Layer

MUTTLEY wrote on 12/30/2002, 12:32 AM
I am using a .png file with standard letterbox lines on the top on the bottom, clear in the middle, that was sent to me by Sonic Foundry to use for letterboxing ( or immitatiing letterbox for standard ratio ). The main video which is below it has what would amount to a " compressed " look to it. I have also tried making my own faux letterbox image using photoshop making the middle blue, than using " Chroma Key " and its eyedropper to key out that specific color but it has the same result.

This problem should be fairly easy to duplicate and is obvious on my external monitor when toggeling the " letterbox " layer on and off.

Any suggestions would be ever so much appreciated, thanks guys.

- Ray

ray@austin.rr.com

Comments

db wrote on 12/30/2002, 1:11 AM
to see the TRUE "results" you will need to either RENDER out to new clip using BEST ( do not put on same track as original) or preview in RAM .. then compare this to orginal ....

for a letter box .. you can also try
add a VIDEO track ( must be TOP track) ..
right click on that new video track and select INSERT TEXT MEDIA
when the text media window pops up make the size 655 x 405 ( or 360 what ever you prefer as letterbox- do NOT change the 655)
next in the PRESET pull down select SOLID BACKGROUND .. then delete the TEXT (in window) -your clip will now have the MIDDLE blacked out - you can see the clip only at top/bottom = this is opposite of what you want...

next look to the very left of the 2nd video track - you will see a arrow ponting up, when you put your curser on it - it will say MAKE COMPOSITING CHILD click it - now a line will go up to 1st video track and there will be a SQUARE with white circle ( curser will say MASK FX) in it... your preview window is now SOLID BLACK ...
now click that square and a window will pop up - in the "TYPE" pull down -select ALPHA .. click on each video track arrow "MAKE COMPOSITING CHILD" (so all tracks are connected - you'll see line going up to each track ) the preview should have black bars only at top/bottom of frame .. now stretch the text media ( drag end) so it covers your whole project ( or sections that you want letterboxed) ..

to change the size of letterbox - right click on text media clip and select EDIT GENERATED MEDIA - again do NOT change the 655 -change only the 2nd number ..
Tyler.Durden wrote on 12/30/2002, 6:20 AM
Hi Ray,

db is on the right track... the letterbox will force recompression of the entire image through the external monitor, unless rendered or prerendered. RAM rendering may not show the final quality, since ram-renders do not add DV compression.

Fear-not, the final output will look very good.

HNY, MPH
MUTTLEY wrote on 12/30/2002, 12:50 PM
Great feedback though I seem to be having the same thing even with the text workaround ( brilliant idea though )and from what I've seen there are the signs of " recompression " even after the render. 95% of the vid has the letterbox, all except for the opening and credits. There is a noticible difference between the sceens that do have the letterbox and those that do not.

Just so its noted, I am rendereing to avi under NTSC DV with the following settings

Audio: 48 KHz, 16-bit, Stereo. PCM (uncompressed).
Video: 29.97 fps, 720x480, Lower field first.
Pixel Aspect Ratio: .909. OpenDML compatible.

Essentially I edit each scene individually as they are fairly complex and this is an 78 - 90 min project. Seems it would just be way to bulky to edit together ( even with dual processors and a gig of ram I dont know that my computer could take it all ). I render each scene with the above settings to avi and than piece the rendered scenes together in what would be the final project. For consistancy I add the letterbox at this stage due to the fact that when I had rendered each scene with the letterbox you could see the black bars fade in and out between scenes.

Thanks for the feedback guys, really dont think I'm just imaginging this. =)

Some of this was just shot beautifully and looks so amazing raw, I truely would hate to comprimise the integrity of the final project and have this slight " bluring " tinge the end result.

- Ray
ray@austin.rr.com

Tyler.Durden wrote on 12/30/2002, 1:26 PM
Hi Ray,

I recently came across some noticable changes and wrote them up over at the cow:

http://www.creativecow.net/forum/read_thread.php?threadid=226743&forumid=24


Hope this sheds more light on the subject...

MPH
MUTTLEY wrote on 12/30/2002, 1:53 PM
Wow, that was a little techy for a newb as myself. =P

If I'm reading it right the gist of what your saying is that by applying an effect to the layer, even if not using its attributes, forces Vegas to process the footage where as it wouldnt otherwise. That Vegas process the footage that has the letterbox because, well, it has a reason to.

What I wasnt getting is which layer are you " Adding a brightness-contrast FX with no adjustment " to ? The Letterbox layer, or the layer below it with the actual footage. After reading your post I have tried both as well as adding the " brightness-contrast " to the individual instances of letterbox and scenes with no apparent increase in sharpness or quality.

Thank god I love doing this stuff or I'd have tossed in the proverbial towel months ago ! =P

- Ray

ray@austin.rr.com
Tyler.Durden wrote on 12/30/2002, 2:16 PM
Hi Ray,

If there is a letterbox the footage needs no null-fx, but native footage will need it to match the letterbox footage.

As for the softness, you shouldn't see any if you are rendering to "best" quality.

You might check the project props, tracks and final-output fx to make sure there isn't any setting awry.


HTH, MPH
MUTTLEY wrote on 12/30/2002, 2:44 PM
Alright, applied it to the native vid as per your suggestion and it does now have the same look, slightly lossy, as that which has the letterbox. Though I am still certain that I am not getting quality in my final render as I would want. I have checked the properties, and already posted the settings in which I render so I'm still at a loss there. Any more suggestions would be most welcome.

Were actually having a premire at a local movie theater Friday so the crunch is on and I know that I will be loosing even more of the clarity when its projected on a movie screen, another reason why my deep concern.

Thanks for all the help guys.

Ray
ray@austin.rr.com
Tyler.Durden wrote on 12/30/2002, 3:03 PM
Hi Ray,

You might check the advanced setings in the props or render template to ensure you have no motion blur applied, or deinterlace.


HTH, MPH
MUTTLEY wrote on 12/30/2002, 3:18 PM
Double tripple checked, none applied.

- Ray

ray@austin.rr.com
MUTTLEY wrote on 12/30/2002, 10:17 PM
Just wondering if anyone has tried to recreate this problem.

And MPH, realy dont want to sound like I'm questioning your powers of observation, but is there any chance at all that your getting the loss I'm talking about but not noticing it ???

Just baffled here and find it hard to belive if this is a glitch in VV that it hasnt been addressed or that I'm the only one thats noticed.

- Ray

ray@austin.rr.com
Tyler.Durden wrote on 12/31/2002, 7:23 AM
Hi Ray,

If the null-fx forcing recompression exhibits the effect, then you may be seeing the colorspace conversion, but it is not common for the effect to be visible. My case was an extreme lighting issue involving the sun in the shot (through clouds). The colorspace conversion is rarely evident with NTSC and PAL compliant video.

The only other thing I can think of is that an inferior codec is on your machine. Do you have any other video apps/ DV codecs onboard? Is "ignore third-party codecs" checked and "Use microsoft DV codec" unchecked? Are you using 3.0c full-version? Did you capture using Vegas Capture?

As for my powers of observation, I'm as fallible as the next person... I'll wipe my specs and take another peek (using footage not so extreme) to see if any difference is visible. But I (like you), would find it hard to believe that something as visible as you say it is, would fly with this crowd. These folks have beat the crap out of this codec and passed it with flying colors.

While we're on the subject of observation <wink>, what is your signal path to what kind of video monitor?

MPH
Tyler.Durden wrote on 12/31/2002, 12:43 PM
Later that afternoon...

Hi Ray,

I ran a few tests, and it was uncommon to detect the shift to rgb colorspace, but i could in one instance. After that though, additional rendering was completely undetectable.

I wonder if you could render (without recompression) a 15 frame segment of your native footage to DV (should stay native), and send it to me... I really like to see what you're working with. 15 frames of DV should be emailable. (If you have webspace for a full-second, that would be really great... yahoo "briefcase" is good for that stuff.)

If poss, send to vegaschains at yahoo dot com, and I'll take a peek.


MPH

P.S. let me know here if you send, I don't check that account too often. mph
MUTTLEY wrote on 12/31/2002, 10:10 PM
You rock. Thanks for all your willingness ta help out on this.

I'm at work right now so dont have all the info but I do know that " Ignore Third Party Codecs " is checked, and Im 90% certain that " Use Microsoft Dv Codec " is unchecked. I am using 3.0c full, and yes all the captures were made using Vegas. As for the monitor not sure the model but its an older Sony 15 inch connected to my Sony GV-D900 with RCA jacks, the Sony GV-D900 being connected to my computer by firewire.

What I did do that showed to me that I wasnt halucinating was burnt one version with the Letterbox to DVD and rendered the raw to DV tape. I cued them up so they would both be in sync while playing them back on my wide screen tv. Switching back and forth it was fairly easy to see. Than pausing each on the same frame and going back and forth between the two it was even more obvious how much detail was missing with the letterbox layer.

What I will try to do is take some of the the project and make a new one with just a small bit with the letterbox, zip it and post it.

Thanks again man, I'll keep ya posted.

- Ray

ray@austin.rr.com
Tyler.Durden wrote on 1/1/2003, 5:36 AM
Hi Ray,

also, could you send the veg file?

That might help a lot too.


MPH
MUTTLEY wrote on 1/1/2003, 1:56 PM
Here ya go MPH, have at. Its a 15 Sec sample veg with all ya should need from the movie I'm doing, a documentary about dancers in Austin Tx. The veg file with all the trimins is 58.9 MB. One of the things I did was to render this to avi than brought it back into Vegas and sync'd it with the raw avi ( uncliced the letterbox layer ) a simple toggle between layers should reveal what I'm talking about. If you focus your attention on her hair youll see a change, as well as an overall " mist " on her face.

http://www.caffeinedeath.com/Rays%20Sample.zip

Back to editing, gotta get this completed by Friday for our premire. Getting it done the priority number one, getting it to look as it should number two.

Thanks all, let me know whatcha think it could be.

- Ray

ray@austin.rr.com

P.S. Not that anyone would be offended by a few curse words but they are in there, I didnt create the dialog, just captured it. Dont think anyone would be bothered but thought I should give a heads up.
MUTTLEY wrote on 1/1/2003, 2:04 PM
Thought I should add that while the chances are slim ta none that anyone on here would live in Austin Tx or be wanting to come but just in case, it will be Friday at the Alamo Drafthouse downtown ( www.alamodrafthouse.com ) at 4:00 PM.

The last thing I want is to sound like I'm promoting here, trust me I realise that if one person from this board showed up it would be a miracle and I don't need the $5.00 that bad. Actually I'll go so far as to say that if there is someone in Austin that would like to come I'll buy their ticket, that way no one can accuse me of advertising on the board.

I only mention this becuase it seemed to me that if someone on here made a movie and edited all in Vegas, if I could go I probably would want to so I thought I would pass it on.

Thanks again all.

- Ray

ray@austin.rr.com
Tyler.Durden wrote on 1/1/2003, 2:25 PM
Hi Ray,

Sorry to say the zip file is munged-up somehow... I downloaded it twice and it wont open in winzip...

:(


Let me know if you can post in some other fashion.


MPH
MUTTLEY wrote on 1/1/2003, 2:31 PM
Lookin at it right now.

- Ray

ray@austin.rr.com
MUTTLEY wrote on 1/1/2003, 2:45 PM
Hm, not sure what to do. Just downloaded it and it opened like a charm. Ya got the latest version of WinZip ? Just taking pokes in the dark.

- Ray

ray@austin.rr.com
Tyler.Durden wrote on 1/1/2003, 3:15 PM
Hi Ray,

Just downloaded the upgraded to 8.1 - no joy.



(your filesize 51,312k)

:(


MPH
Tyler.Durden wrote on 1/1/2003, 3:19 PM
Hi,

Speaking of shooting in the dark, would it help to take the space out of the filename?

MPH
MUTTLEY wrote on 1/1/2003, 6:17 PM
Whelp, u/l'd it with the name change, cant imagine that it would make a diff. Is anyone else having the same prob ? Mayhaps it wasnt done uploading yet ?

http://www.caffeinedeath.com/raysample.zip

- Ray

ray@austin.rr.com
Tyler.Durden wrote on 1/1/2003, 9:13 PM
Hi Ray,

I did manage to get the file.. this one is bigger.

I checked yer letter box against one I made and they both pass video through cleanly (no hazing due to bad alpha).

The goofy thing is, I can't see the problem here. I rendered to best quality: five secs with letterbox off, then popped in the letterbox for another five (continuous footage. Looks seamless here.

I even blocked my view of when the letterbox pops in to see if I could detect when the rendering was active... could-not-tell.

I'm using a handycam as convertor, s-video out to a Sony PVM-1342Q production monitor with less than a hundred hours on it.

SO, we may have some open questions: Is it your monitor responding to the shift when the bright background is more-blocked by the letterbox, or is your system using an inferior codec, or am I going blind faster than I thought?

It is a good looking image, I must say. I hope your monitor is at fault and you are getting the full advantage of the Vegas codec.

When you have time, render me the same segment with the letterbox and post it... I'll compare it to my render.

Good luck,

MPH



MUTTLEY wrote on 1/2/2003, 12:08 AM
Okay, it should be up, but its big ! I didn't want to zip it because I didn't want to risk any possible interference with further compression.

http://www.caffeinedeath.com/sample.avi

Well I'm baffled. I swear ta God I'm not hallucinating this, if should it to several friends and they could see the loss and just now after reading your post forced my gf to look again, she saw it.

It hasn't mattered what I'm looking at it on, my monitor, my Sony GV-D900's screen, my fifteen inch broadcast monitor, and my pretty new 55 inch wide screen TV.

Try pausing it and toggling as I suggested. Do it on a frame that has little motion, watch especially the ring on her hand and the writing on the yellow thingy around her neck.

PLEASE TELL ME IM NOT CRAZY ! =P

Bring the one I just posted into Vegas, put it on the layer below the original footage, turn off the letterbox on that footage. Pause and toggle my friend Toggle, like its the last day on earth !!!

Boy could I use some reinforcement here.

If ya don't see it ya don't see it and aside from flying you here so I can point on my system I guess we my have reached an impasse. When you get a chance try to look at it as I suggested, meanwhile I'm crossing my fingers hoping someone will know what I'm talking about.

Thanks bud and sorry for the big d/l's.

Ray