How to get crawling text to look good?

farss wrote on 8/27/2004, 5:20 AM
My first go at this and it looks pretty bad. Created text in PS with alpha, saved as .png. Composited that over video and used event motion to move it across the frame. Tedious when you need it to run every 30 seconds so I rendered just the crawling text as uncompressed avi with blank section, much easier to just drop a 30 second event 50 times onto the TL.

Anyway after rendering the whole thing out the text looks really bad, lots of horizontal blur. Make sense as between each field the text moves about as much as the verticals are thick. But I've seen this on TV, quite fine text crawling faster than mine and it looks perfect.

I'm wondering if using supersampling when I render the inital text out to add some subtle motion blur would help. Anyone done this before and got decent results?

I know it can be done within the confines of the video system, but how?

Bob.

Comments

mrjhands wrote on 8/27/2004, 7:09 AM
No answers; plenty of sympathy. I have slipped into OBSESSION at times in the past, trying to mimic the clear, sharp FoxNews and CNN (heck even local stations have nice crawls) CRAWLING text. Started with the speed of movement, CNN being the slowest (bout 6 seconds from right to left, if you pick out a character in the crawl, follow IT, and time it) and FOX 'bout 4.5-5 seconds tops from right to left. Text size and font style considerations, bout 18point Arial and other sans serif fonts. I've tried literally 100 variations from doubling text size to 1440x960, supersampling, motion blurs, rendering to new track first, from variations in text COLOR, duplicating tracks with different settings, track motion vs. crop and motion motion, vector titling programs like Boris, Zaxwerks Pro Animation...yada yada, bottom line appears to be it can't quite be duplicated to that quality. My belief is it must be due to the fact that the quality crawls we want to emulate are being transmitted real-time, UNCOMPRESSED with expensive stand alone character generators with better algorithm, interpolation WHATEVER. HOWEVER, I ran a test; I view my PREVIEW IN PLAYER renders with my TV(I dont have DV device to preview from timeline, I send my SVideo cable from Video Card direct to TV, ran my compositeRCA to OTHER input on TV. Now, RCAComposite always messed with my computer graphics, looked like crap of course. SVideo is improved, but I thought what if I burn to DVD first (Im new to DVD Burning), stick DVD in player thus bypassing the signal degradation of video card output to TV and see if I have my flawless text crawl. The answer? I dont know, Im all out of DVD blanks and wont have any until Monday; but if YOU can do it, why not try burning to DVD and seeing if the MODE that you are previewing on your external monitor isnt causing the crappy looking text. Let me know!
farss wrote on 8/27/2004, 3:05 PM
Already burnt to DVD, looks like c**p.
Your are right, a lot of this stuff is done in real time using purpose built hardware. That gear is built by those who understand how to make text look right on a video system as opposed to a graphics system. There are subtle differences due to the way motion and pixel mapping works on a video system.

But I may have an answer. The issue I suspect is interlacing, Vegas renders the characters into one position in field A and then computes the new position and renders that position into field B. Technicaly in an interlaced video system this is correct however that doesn't mean it'll give the best visual result to the eye.
So I'm going to try rendering it in progressive first. This means the two fields when converted to interlaced will have the characters in the same position. That means a loss of temporal resolution but an improvement in spatial resolution (perhaps).
If that fails two other solutions come to mind. I'll get a good quality copy of a stations output and analyse that. Also I'll get someone to do it for me using a real CG box although this means I'll have to CK it which will ditch some quality. Only VERY high end VCRs record separate alpha channels, damn.

Of course the other issue could well be DV25 and 4:2:0. I could also try going directly from the Vegas T/L output into the mpeg encode thus giving the encoder 4:4:4 but I've pretty much done that by keeping the text uncompressed.

Bob.
Jessariah67 wrote on 8/27/2004, 4:36 PM
Hey guys,

I just tried a crawl and it didn't seem to turn out too bad -- probably would have looked better over a black banner, like the news networks. You can look at it here. (Warning - it's about 8MB). There is WMV compression and it may be a little bit too small...

Does this look better than what you guys are coming up with?
farss wrote on 8/27/2004, 4:58 PM
Hard to truly judge, it's running about hald the speed of what I'm aiming for. Ideally the text should crawl at the same rate most people can read at. Also it's probably been compressed into progressive scan!
I've seen crawling Chinese (lots of fine detail) that really flies and still looks great. Probably helped by the higher frame rate of NTSC but even so.

I'm going to try the progressive trick to see how that works out.

This is one of the things that bugs me a bit about Vegas. It's a great multimedia authoring toolset but at times you need to be conscious of what your target media's limitations are least things come unstuck. I'm not being critical, more a head up kind of thingy, Vegas and video is not alone in this problem. I've made terrible boo boos for much the same reason in other areas by not truly understanding my target medium.

Bob.
Jessariah67 wrote on 8/27/2004, 6:24 PM
Bob,

I changed the link to this new version. Looking at the AVI, it's pretty smooth. I set up a PSD @ 5000x480 and typed out the text at the bottom, then brought the PSD in (text on transparent BG) and used the Pan/Crop to position the text, then run it across the bottom.

If you want the PSD to test full rez at your end, let me know.

KH
mrjhands wrote on 8/27/2004, 9:11 PM
No, to me it has the same problems my crawling text has...scan lines make up 50% of the text. What I would like to do is record some good crawls off of Fox or CNN to my HD< then play back thru my means, to clarify if MY setup isn't causing some breakup, or excess non-clarity. (BTW, I am aware small fonts don't make for the best scrolls, but, the pros are making it happen some how.
apit34356 wrote on 8/28/2004, 1:03 AM
Have you tried creating a new project with high frame, ie>60...to 1000 fps.... for building the scrolling text with the sony media text?
farss wrote on 8/28/2004, 2:40 AM
For sure it'd look great at that frame rate, dang if there was only a video system that could play it back!

Bob.
farss wrote on 8/28/2004, 5:58 AM
Results to date:
1) Starting with progressive scan helps. Render out to uncompressed AVI progressive scan and the bring that into normal DV project i.e. interlaced, and it looks better. This avoids the temporal separation between the fields. Resulting motion isn't quite as smooth but the text tooks way better but still not perfect.

2) I'm now trying apit's suggestion, went for 100 fps progressive. 15 seconds of uncompressed AVI at 100 fps, 2.4 GBytes, thankfully I have big disks. Rendering that back to 50i is taking a while. Should know if it looks any better soon.

Well apit, it looks GREAT! Who would have thought. But this makes sense in some wierd way. Now Vegas has 4 frames of source for every one of output, hm, lots of interpolation to be done but I think this is working because of this:

A frame is 787 pixels wide and the display is updated at 25 fps. Therefore assuming the text moves one pixel per frame then it needs to take 31.48 seconds to cross the frame. Doing it in half that time would also be OK, it then moves 2 pixels per frame. Anything other than those magic numbers are going to be problematic, how does Vegas map a pixel that is halfway between two output pixels?
I know high end CG systems use subpixel mapping to get around this. I've never had an answer as to whether or not Vegas does this although I suspect not.

Bob.
farss wrote on 8/28/2004, 7:32 AM
Excuse my maths OK. dumb aussie at play.

The trick is to work the magic numbers. By making the text move an integer number of pixels per frame I can get it whiz accross the screen and still look great.
Here's the 'cookbook'.
Firstly create your long text in PS, use an image some height as the frame (576 or 480) and make it wide enough to hold all text text. Save as whatever but PNG would be good.
Now drop that onto T/L in a progressive scan PAL or NTSC frame rate project. Make it around about how long you think you'd like it to take to crawl accross the screen. Open event pan crop widget.

Enable cursor sync and goto first keyframe. Set window to same size as frame (787x576 for PAL), move X position to get your text just out of frame but make certain it's an integer number of pixels offset (in my case 350). Now in my case I needed to move it 2000 pixels in 10 seconds or 8 pixels per frame (25x8x10 = 2000). This gives pretty quick crawl and please take note, the numbers will be different for NTSC! Also set smoothness to 0 for both the first and last keyframe else your text accelerates away / towards the keyframes which blows the clacs out of the water.
Now if all is correct as you move the cursor frame by frame along the event pan/crop TL the X position should always be an integer, in this example it changes by 8 pixels per frame.
If that's correct now render out to uncompressed AVI, 25 fps (or whatever odd number NTSC needs), still progressive, bring that into a new standard DV project, you know the drill I hope! You might need to force Vegas to recognise the alpha channel, render that out and you'll see wonderous crawling text as good as anything I've seen on TV!.

In summary two things to make it fly:

1) Keep both fields the same by first rendering to progressive.
2) Get the text to move an integer number of pixels each frame to avoid any interpolation ( or perhaps lack thereof?).

PS For those in NTSC land, things might be a lot easier switching the timeline to frames rather than time, convert the time to frames at 30 fps, it'll easily be close enough.

Bob.
mrjhands wrote on 8/28/2004, 8:25 AM
WOW! You go guy!

Excellent that you are pursing this; first free minutes I have, prolly tomorrow Sunday, I'm going to dig into this and see if it works for me, I'm anal about the text crawlsLOL

If this works you might want to see bout creating a SCRIPT for making this a one two click kinda thing(I dont know jack about scripts), or formulate it into a nice little plug in using all that math to do the hard part for us!

Can't wait to try it out! So, my text looks like that example the other poster put up? Did yours too previously? Did this really shape it up? Cool..............
johnmeyer wrote on 8/28/2004, 12:09 PM
I have always wished Sony would not only create a FAQ on this forum, but also a collection of the brilliant solutions that various people have posted here. Wouldn't it be great to have dozens and dozens of these incredible solutions all in one place?

farss, I've been told that I should call someone like you a fair-dinkum. Hope that's the right term. Here in California, my kids would call you an awesome dude.
farss wrote on 8/28/2004, 3:35 PM
Thanks for the kind words.
John, for my generation fair-dinkum is right but the next generation down here has picked up the 'awesome dude'. We are now truly a global village.

To the issue at hand, yes previously the results looked very bad, bad to the point of affecting legibility. Using this technique it looks perfect, probably the only thing holding it back is that I only have a composite feed to my monitor. Prior to using this technique I knew something was seriously wrong, looking at it on the PC monitor it looked woeful, even rendering progressive it looked very soft, rendering interlaced the field offset was nearly as large as the thickness of the verticals in the characters.
The latter I knew would make the text look aweful. What makes it worse is with crawls the eye doesn't get a clear look at it ever. Look at any video, no matter how well it's shot. Motion blur and interlacing does introduce motion artifacts that lower the real resolution however we see that as normal. Our brain copes with it because either before or after the motion we had a clear view of it while it was static. But the crawling text is never static so we never get a clear look at it. So to make it acceptable to the brain we actually need to create something abnormal to the eye, motion with no motion blur or artifacts.

BTW, I got the clue to how to solve this from a fairly old article, I think by Adam Wilt, about how the old style CG equipment worked.

Bob.
aussiemick wrote on 8/28/2004, 5:56 PM
Proud to be in the same land, but don't expect the same level of brilliance, this one is a bit of a dummy!
But SONY please give us a page for brilliant solutions! Got to be in your interest.
John is right, he really is, definitely so, on the mark etc.... etc.....!
Now is the time!!!!!!!!!!!!!
apit34356 wrote on 8/28/2004, 11:03 PM
farss, yes the issue is motion blur with vertical text, as the pixal moves, it can not be solid then clear. The blurring effect creates levels of shade reflected by time of text pixal existence at a fix location. creating a large fps, its helps the sony blur software calc. delay time.at rendering stage. The human eye uses the blurring effect to signal movement..
johnmeyer wrote on 8/29/2004, 7:42 AM
farss,

In re-reading your technique, one of the most important steps is to make the pan for each frame an integer sub-multiple of the total pan in order to avoid interpolated frames. I can see how this works, and it is probably the ultimate way to go, but wouldn't you get much of the same effect by turning off resample for the event you are panning? I admit that you would still get a stutter occasionally when Vegas has to move the text ahead by one pixel more or less than the it did for the previous frame, but for most work it would be pretty close.

Even when using the method you describe (which is clearly the best way), I would think turning off resample would be a good thing, just in case you are off slightly on your calculations.
farss wrote on 8/29/2004, 8:00 AM
John,
I hadn't though about the resampling issue at all as I've never quite understood precisely what it does. I'll try that later.
The calculations are easy enough to check, in fact this is how I started out, sort of brute force.
If the values are correct then as you step along the TL in the event pan/crop window watch the X position value, if you're right it'll always be an integer number.
Two things in Vegas I don't yet understand, just what Reduce Interlace Flicker does, I mean I use it a lot to stop all sorts of aliasing problems but I don't know how it's doing that. The other is resampling. I know, probably I should RTFM but at the moment I have a huge backlog of work so I'm just trying to plow through it.
Current client is a PIA, big time!
Their graphic artist gives me a PSD to use as DVD menu, except it's got 4 buttons labelled A,B,C,D. Author DVD, give to GM and turns out I'm an idiot, didn't I know they didn't want D on this DVD!
The best client I've had EVER was yesterday, first time I've actually edited to a script! And the scary thing, she's only nine years old, go figure.

Bob.
farss wrote on 9/3/2004, 6:05 AM
I took my NTSC DVD with its text crawl to work and had a look at it on a decent monitor. Well Yuck hardly describes it. Anyone who thinks you can do serious work without a studio monitor is out of their tree.
What I thought was just the poor resolution of my el cheapo TV doing sevices as a monitor was actualy hideous interlace artifacts being hidden by the poor res of the monitor. So back to the drawing board!
I gave up using long text generated in PS and on first rendering to progressive scan. When I thought about it moving a card with text written on it in front of a camera shooting 60i looks fine so Vegas should be able to do it, right?
So I used a couple of tracks of Vegas text with event pan and staggered the events to get the text segments to look like they're all one. However I found adding a black border and a little shadow helped. I still kept the motion at integer pixels per frame.
Render results on a NTSC DVD looked great. Only glitch in the DVD was the hue was out! Apart from that, even to my mates who work in broadcast, the PAL to NTSC conversion looked excellent. But the hue thing?
Ha, I'd forgotten about NTSC, the 'HUE' control on the monitor was way off, doesn't do anything in PAL of course!! I'm finally starting to understand this NSTC stuff.

Anyway, I degress. The crawling text looked excellent, no artifacts at all, except for a motion artifact, the text is slightly sloped. Now I know why there's a control in the text generator! Of course a true broadcast CG system would compensate automaticaly. Ah well, we got 3D planar surfaces, pity we have to do a lot of experimenting to do something as basic as text crawls that look half decent.

Why my obsession with this, apart from the client wanting it. Well the original video that I'm putting into the DVD was edited on a old Casablanca system, a turnkey DV editing system hardly known for it's spectacular performance but guess what, its text crawls are perfect! Now the pros tell me Casablanca are good at making systems for editing by the numbers. Well it might be a very simple system but it seems what it had was basically goof proof, although it can't cut audio right, every cut in the middle of something audible has a glitch in it.

Bob.