-
Scrolling text expressions sollutions?
Greetings all,
Please somebody help me as my job is on the line here.
I know that this has been discussed over and over again.
I have been reading the forums for 2 days now and trying almost every
suggestion that is relevant to my problem. None seem to solve the issue of jittery scrolling text.
I am not talking about judder IE the leading edge flickering.
The problem that I am experiencing is what seems to be like random dropped frames where the text seems to jump forward in time.I am rendering progressive uncompressed MOVs for display on low resolution LED video displays that take DVI straight from the computer
graphics card @60hz,
The comps that I am rendering are 480×80 30 or 60fps and the text is set to move in multiples of 30 or 60 to keep with the frame/refresh rate.
The rendered MOVs display the same problem on the monitor as the do on the LED screen. its just easier to see when the letters as 15 feet tall.I have tried ….
motion blur,
frame blending,
Gaussian blur,
Different speeds,
different FPS,expressions that have helped but not solved the problem.
[Math.round(position[0]),Math.round(position[1])];
loopOut(“continue”);[Math.floor(value[0]), value[1]];
loopOut(“continue”);I would like to try this expression but there is something in the syntax that I am missing.Probably something simple but I’m still pretty green when it comes to expressions.
intPixelsPerSecond = -60;
(x=position[0]-((time-inPoint)*intPixelsPerSecond);
[position x,[1]]I refuse to believe that there no solution and that is this all a matter of perception and the condition of the human brain.
My job as the content producer for this company is on the line
if I can not find a way to smoothly scroll text by itself.
I have found that by adding organic kinetic backgrounds or overlays
distracts from this problem , But it still exists.Is this possibly a hardware issue?
where the mov does not play insync with the graphics card output refresh rate.machine specs:
Machine Name: Power Mac G5 Quad
Machine Model: PowerMac11,2
CPU Type: PowerPC G5 (1.1)
Number Of CPUs: 4
CPU Speed: 2.5 GHz
L2 Cache (per CPU): 1 MB
Memory: 4.5 GB
Bus Speed: 1.25 GHz
Boot ROM Version: 5.2.7f1
Serial Number: G8605038R6WNVIDIA GeForce 6600:
Chipset Model: GeForce 6600
Type: Display
Bus: PCI
Slot: SLOT-1
VRAM (Total): 256 MB
Vendor: nVIDIA (0x10de)
Device ID: 0x0141
Revision ID: 0x00a4
ROM Revision: 2149Displays:
DELL 3007WFP:
Resolution: 2560 x 1600
Depth: 32-bit Color
Core Image: Supported
Main Display: Yes
Mirror: Off
Online: Yes
Quartz Extreme: Supported -
6 Replies
-
I can help you with your syntax:
intPixelsPerSecond = -60;
x=position[0]-(time-inPoint)*intPixelsPerSecond;
[x,value[1]]Dan
-
Thank you Dan for your prompt response.
Unfortunately this did not solve my problem.
Any other expression ideas that might help?
or is this now in the wrong forum? -
Does it only look bad on your special output device, or also on the computer screen ?
Is the jump very regular (like once every 1.2 seconds) or just erratically now and then.What is the refresh rate of your grahics card ? Is it exactly 60 HZ ?
Find out and use a framerate that corresponds.Does the LED device have a preferred framerate in it’s documentation ?
Does it have any software that comes with it (even some demo of VJ software)
Does a similar problem exist there ?I’m pretty sure this is hardware related, not perception judder stuff.
Hound the company that manufactures or sold you the device, make them demonstrate how they can have smooth scrolling text without your issue.
Don’t loose your job over crappy material.and -shiver- try the same with a PC.
-
Thanks Filip for your response and concern.
[Filip Vandueren] “Does it only look bad on your special output device, or also on the computer screen ?
Is the jump very regular (like once every 1.2 seconds) or just erratically now and then.”It does show on the monitor. as well as the LED display.
It is random. Meaning an 8 second test render loop
open in 2 windows playing at the same time will skip
at different points every time they loop and not the
same on both loops.
My refresh rate is exactly 60Hz and my FPS is the same as well as my pixels per second key frame movement set to loop out”continue”
It must be a hardware issue as a coworker of mine generated a MAX/MSP_Jitter patch that generated and scrolled text with open GL directly on the graphics card and still saw the same skip or pause in the horizontal scroll.[Filip Vandueren] “Hound the company that manufactures or sold you the device, make them demonstrate how they can have smooth scrolling text without your issue.
Don’t loose your job over crappy material.”Funny you say that as I have been with the company for almost 3 years now from the old start-up days as a tech and am now working on content 90% of my time and if I cant figure this problem out I will not have the opportunity to do content for theme anymore.
This has always been an issue but its not just our gear as we see it on different platform CPU’s from laptops to maxed out towers.
This is just the first time I have approached this cow_munity with this problem. I really want to keep creating content but I’m afraid that if I don’t find a solution they will outsource it all.
This is probably not the place to discuss this any more .
Guess I’m screwed.ugh.Any hardware that I might want to try to solve this problem?
-
Well, if they outsource the creation of content, and they play it back on this system, it seems to me they will not have solved the problem…
It’s probably a bit harder to test, since the array is only 80 pixels high, but does the problem also exist with vertical motion?
Though it should not pose a problem on a highend system like yours, have you tried quicktimes with a compressed codec ? The bandwidth of a non-compressed 60FSP movie streaming from harddisk could be the bottleneck.
Does the skipping occur on your monitor when you ram-preview in after effects or only playing back the Quicktimes ? If so: that could be the culprit.
How is the movie sent to your LED-system: is it hooked up as a secondary display, what software is playing the quicktime ?is DVI the only input to the LED-system ? Could you hook up, say, a DVDplayer to it and check that for skippyness.
-
Thanks again Filip for sticking with me on this.
[Filip Vandueren] “Well, if they outsource the creation of content, and they play it back on this system, it seems to me they will not have solved the problem…”
I agree this will only pass the problem on to someone else who will cost more than I do. If I cant figure a solution I at least need to
be able to definitively explain why we cant display scrolling text,
and if they do out source it to some one who can figure it out . Well, thats it for me.[Filip Vandueren] “It’s probably a bit harder to test, since the array is only 80 pixels high, but does the problem also exist with vertical motion?”
Actually its more apparent on the LED display as the pixel pitch is 1 inch. So the display is just over 6 1/2 feet tall. This size magnifies
any jerky movement. I have done less experimenting with vertical repetitive motion as it has never been an apparent problem.
Tho now that you bring it up I will have to make sure that it is only on the horizontal and not the vertical. My guess is that this is where the brain comes in,as the horizontal is much more perceptually apparent but it probably does still exist on the vertical as well.
I will test this tomorrow.[Filip Vandueren] “Though it should not pose a problem on a highend system like yours, have you tried quicktimes with a compressed codec ? The bandwidth of a non-compressed 60FSP movie streaming from harddisk could be the bottleneck.
Does the skipping occur on your monitor when you ram-preview in after effects or only playing back the Quicktimes ? If so: that could be the culprit.”I have indeed tried many compression formats. Unfortunately these make
the display somewhat dithered looking even at the highest setting. I have chosen uncompressed for the most saturated and crisp look.
I have set the QT files to pre load to RAM in QT pro.
30fps shows the same jerkyness.
The skipping is also displayed when ram previewed in AE.[Filip Vandueren] “How is the movie sent to your LED-system: is it hooked up as a secondary display, what software is playing the quicktime ?”
Yes, typically it is sent as a secondary mirrored output from a mac book pro. Sometimes we use mac minis and just loop out of our gear to show the display on a DVI monitor. But the problem still exist on the monitor of my render machine as well as the G5s, macbooks, minis and various PC’c that we use.
The software that we use to display the small size videos is usually QTpro or custom MAX/MSP/Jitter open GL media servers that we create.
The inspectors on these media servers show that we are getting the proper throughput and FPS I just cant figure out where the frames are getting dropped.
I don’t think its a psychological issue because two people will see the skip at the same time and it does not skip in the same place on the time line in a loop.[Filip Vandueren] “is DVI the only input to the LED-system ? Could you hook up, say, a DVDplayer to it and check that for skippyness.”
DVI-D is the only input but I can take say SDI or RGBHV and convert it.
The only issue is that I would have to render all of my comps at full screen resolution with a “480×80” window.
This might dramatically increase my render time when I am doing a comp that is say 64×80 or even 50×50. Its worth a shot though as I do have a DVD player with DVI out. I am also thinking about trying a Doremi or fast forward hard disk player/recorder. But if it shows in AE ram preview why would this help?
What about flash movies? They seem to have a very small file size even
with the best settings.I also seem to remember seeing this in some older flash comps that I made as well as Vegas comps too.I have also seen this problem in quartz composer ticker tape apps.
and these are very low band width apps generating text directly on the graphics card using open GL but the skip could come from the app polling an RSS feed to generate the text.
Some other people we saying that they did not see this on there AVID systems but they might have been talking about Judder which I now have control over using the expression found on this forum.All I need to do is a scroll text.
Of all the exciting and challenging programming gigs I’ve had.
This is by far the dullest problem but the most important one in my
career to date.
Why something so simple as moving text from here to there
would be so difficult it baffling.Again thanks for your support.
-jason
Reply to this Discussion! Login or Sign Up