13 Replies Latest reply on Apr 27, 2016 10:35 AM by techinis

    AE 8 TEXT layer scroll creates text character jitter/flicker

    Wes Cox

      Using CS3 AE 8 to add text layer over a fractal effect on gray solid layer.  Text layer has position KEYFRAMES to cause text to look like scroll from bottom to top.  SCROLL changes speeds (slows) after the first 10-12 lines.  Effect is text on lines after line 13 show character jitter or flicker. Line movement up the screen has pixel flicker on letter characters.  Effect looks like frame rate, interlace and scroll speed interaction.  Are there specific requirements for text box in text layer when using KEYFRAMES?  I don't see an adjustment to the scroll rate except increaing the COMPOSITION duration and spreading the TEXT layer KEYFRAMES of the longer time period.  Transition properties on TEXT layer do not have a frame rate adjustment.

      Anyone with experience using TEXT layer withnumber of text line greater than 200 in a COMPOSITION?

        • 1. Re: AE 8 TEXT layer scroll creates text character jitter/flicker
          Mylenium Most Valuable Participant

          It would really help if you formulated proper sentences rather than sounding like a computer translated Chinese tech manual... Anyway, Rick Gerard has answered this a million times in relation to anything from credit rolls to panning images, so do a search on this forum. Some of his deep wisdom and insights are gonen crop up. The short version is, that your speeds must be even multiples of the frame rate, possibly also in relation to the size of your text. Moving text by crooked amounts between frames will have the inbetween steps end up at different positions for each frame, possibly "eating up" details in the typefaces and resulting in the perceived positional and shape flicker. That's all there is to it. Of course additional techniques and tricks like using motion blur, tiny amounts of directional blurs, outer glows and what have you to increase the pixel area of a font also apply...

           

          Mylenium

          • 2. Re: AE 8 TEXT layer scroll creates text character jitter/flicker
            Rick Gerard Adobe Community Professional & MVP

            If your final output is interlaced then you must move the text exactly 2 pixels per frame to avoid this jitter. If the text has very fine lines then you must also pick a font size that is exactly an even number of pixels wide. I usually do this by setting the composition view to 800% or more and adjusting the type size, leading and baseline offset. If you hold down the Cmnd/Ctrl key while scrubbing the values in the Character panel you will be able to make fine adjustments.

             

            This is wrong spacing. Look closely at the "t" and the "e":

             

            Screen Shot 2011-10-16 at 10.52.13 PM.png

             

            This is much better spacing.

             

            Screen Shot 2011-10-16 at 10.52.40 PM.png

             

            Once you have you font size, leading and baseline shift set the easiest way to animate a smooth roll is with an expression. I like this one applied to the anchor point.

             

             

            x = value[0];
            s = 2; // speed in pixels per frame
            m = time/thisComp.frameDuration;
            
            y = value [1] + (m * s);
            
            [x, y]
            

             

            The speed should be an even number for interlaced delivery and must be a whole number for all others. I've set it to 2 which is a nice readable speed for SD displays.

             

            If you must change speed in the middle I'd suggest that you add some keyframes to the anchor point or position. Just do a little simple math to figure out where the keyframes need to go.  Don't expect to avoid jitters as the speed changes.

             

            Once you have things set up so they look pretty good add some motion blur. I suggest about twice the normal amount for interlaced delivery and 3 to 4 times the normal amount for progressive. That means at least a 270º shutter for interlaced and at least a 360º shutter for progressive.

             

            I hope this helps. Text rolls are never easy to perfect. Just watch the end of any movie on TV or in the theater. Some day I should do a tutorial on perfect text rolls.

             

            Message was edited by: Rick Gerard Make that a million and one...

            • 3. Re: AE 8 TEXT layer scroll creates text character jitter/flicker
              Wes Cox Level 1

              Thanks. I saw your solution in a prior discussion string.  I am not experienced with expressions or with pick whip function.  I found an article updated August 25,2011 on EHOW website titled "How to Make Scrolling Movie Credits in After Effects."  The process uses NOTEPAD for text creation, then AE to create new Composition and use add text layer andcopy/paste NOTEPAD generated text into AE text box.  Procedure uses TRANSFORM POSITION KEYFRAMES to roll the text box vertically from bottom to top. Procedure was easy to follow but visual results are not the best.  I assumed that I had not created the text box correctly.  Will your expression attached to the TEXT layer TRANSFORM ANCHOR POINT have the right effect on this Composition?   Am I required to ANIMATE the TEXT layer then apply the expression to the ANCHOR POINT?

              • 4. Re: AE 8 TEXT layer scroll creates text character jitter/flicker
                Rick Gerard Adobe Community Professional & MVP

                All you need is a text layer and to apply the expression to the anchor point of the layer. The layer is positioned to start the credit roll with the first line at the bottom of the frame. Then it just needs to be long enough to let the last title roll off the screen.

                 

                I haven't seen the tutorial that you're talking about but animating the anchor point is not much different than animating the position. Creating the text first in notepad is ok. All you have to do is select all the text in notepad then copy, then create a new text layer in After Effects, double click the text layer to select the empty text and paste. You shouldn't be drawing a text box because there's no way to tell how big it needs to be.

                 

                Once you've got the lines of text in AE as a single layer you should adjust the font size, leading, and base line shift with the entire layer selected to line up the bases of the lines exactly on a row of pixels.

                 

                You then press the letter A to reveal the Anchor Point property, hold down the Alt/Option key to add an expression, then paste the expression I gave you into the text field that opens up.

                 

                Go back to the direct selection tool and position the text for the start of the credit roll and you're done.

                1 person found this helpful
                • 5. Re: AE 8 TEXT layer scroll creates text character jitter/flicker
                  Wes Cox Level 1

                  Thanks.  Instructions are clear.  I am not experienced at adjusting base and leading properties.  I adjusted the font size to sharpen the letter edges.  I adjsuted base to sharpen the letter horizontal edges. Next I adjusted lead to sharpen the letters line to next line.  From your png image I thought the goal was to make a character have the same image line to line regardless of position in the frame.   My resulting roll is still not smooth.  It looks like my pixel size is too large for the font size resulting in the letter flicker.  The frame is NTSC standard.  I will continue to work with the font size, base and lead properties.

                  I typed your expression with no errors and it is loaded into the TEXT TRANSFORM ANCHOR POINT. I can't see that it is working correctly as there is little effect with expression ON or OFF.  I will continue tomorrow,

                  • 6. Re: AE 8 TEXT layer scroll creates text character jitter/flicker
                    Rick Gerard Adobe Community Professional & MVP

                    If you apply the expression to the anchor point of the text layer and then drag the CTI indicator down the timeline you'll see the text scroll. You want the Transform>Anchor point and not the Text>Animator 1>Anchor Point. You can use the second but the range selector can easily foul things up.

                    1 person found this helpful
                    • 7. Re: AE 8 TEXT layer scroll creates text character jitter/flicker
                      Dave LaRonde Level 6

                      Wes Cox wrote:

                      I thought the goal was to make a character have the same image line to line regardless of position in the frame.   My resulting roll is still not smooth.  It looks like my pixel size is too large for the font size resulting in the letter flicker.  The frame is NTSC standard.  I will continue to work with the font size, base and lead properties.

                       

                      A lot of that isn't necessary.  Not all fonts are created equal, and you're bound to bump into spots on letters where an edge crosses in the middle of a pixel, and AE's subpixel rendering kicks in to keep things smooth.  You can't do anything about it.  It's all part of antialiasing.

                       

                      The important point, as Rick has pointed out, is to keep the layer moving in EVEN PIXEL INCREMENTS ONLY on a text roll.  This would be 2, 4, 6, 8 etc. pixels of vertical movement on each frame.  The vertical position could be... oh, a Y-value of 521.0038 on a frame as long as it's something like 517.0038 on the next frame, which would be a change of 4 pixels.  This is especially important in interlaced SD NTSC.  By moving in even pixel increments only, the top & bottom edges of the letters fall in the same relative position to the subpixel rendering, so the edges look consistent.  You don't get the illusion of the edges frying.

                       

                      I'm stumped by what you mean by "my roll still isn't smooth", because you withhold important information.  HOW is it not smooth?  Jerky motion?  Frying edges? 

                       

                      What's your comp's frame rate?  29.97 with interlacing, which can allow pretty smooth vertical motion, or 23.976 frames/sec, which does not?

                       

                      How are you looking at the motion?  On a RAM Preview?  Does the frame rate of the preview match the comp's frame rate?

                       

                      Are you looking at a rendered file on a media player?  On a video monitor, and not a computer monitor?  What kind of file did you make in AE?  What's the codec?  What's the playback hardware and software? 

                       

                      At the moment, a "not smooth roll"  is a meaningless statement.

                      • 8. Re: AE 8 TEXT layer scroll creates text character jitter/flicker
                        Wes Cox Level 1

                        I did add the expression to the TEXT anchor point in the transform.  I did not animate the TEXT layer so I don't get confused with the animation transform anchor point.   I have been viewing using the composition window and space bar or CTI in the timeline.  I was not using RAM PREVIEW..  RAM PREVIEW is acceptable video.  I will  use the COMPOSITION DURATION and TEXT position to adjsut the speed.  Thanks for your help.  Some of my problems are pilot error and some you have solved. 

                        • 9. Re: AE 8 TEXT layer scroll creates text character jitter/flicker
                          Wes Cox Level 1

                          Dave, thanks for your comments as I was not using RAM PREVIEW but just using CTI to scrub the video in the COMPOSITION PANEL.  I know to use the RAM PREVIEW but was NOT.  I am using 29.97 which I thought was default SD NTSC(I don't mess with frame rates).  Your phrase "frying edges" is one aspect and "JERKY MOTION" is the other and both are reduced/eliminated with RAM PREVIEW.  I will now export to Premiere to add the "CREDITS" composition to the PPRO timeline. 

                          RAM PREVIEW eliminated the gross jitter and jerky text motion and with Rick's anchor point expression the roll looks acceptable.  I'll see what the PPRO project(SD NTSC) looks like with this composition.  Thanks for your comments

                          • 10. Re: AE 8 TEXT layer scroll creates text character jitter/flicker
                            Dave LaRonde Level 6

                            Wes Cox wrote:

                             

                            I am using 29.97 which I thought was default SD NTSC(I don't mess with frame rates).  Your phrase "frying edges" is one aspect and "JERKY MOTION" is the other and both are reduced/eliminated with RAM PREVIEW.

                             

                            Glad to hear things are looking up.  Your feedback leads me to believe that you haven't rendered anything yet.  You should know that if you render a lossless file, the playback will probably be jerky.  That's normal for many, many machines that don't have RAIDs.  The resulting credit clip will very likely need to be re-rendered in Premiere; that's pretty normal as well.

                             

                            You may not have to mess with frame rates at the moment, but it's a very valuable thing to learn; not knowing how to deal with them can mess a project quickly.

                            • 11. Re: AE 8 TEXT layer scroll creates text character jitter/flicker
                              Wes Cox Level 1

                              Dave, thanks again.  I will render in Premiere.  Is there some AE EXPORT to Premiere condition/parameters or some IMPORT in Premiere from AE conditions/parameters that I should use or at least be aware.   I have used the IMPORT inside Premiere to pull compositions from my AEP project.  I intend using the same technique unless there is a down side.  Anything that I should know before I use this technique or should I use a different technique?

                              • 12. Re: AE 8 TEXT layer scroll creates text character jitter/flicker
                                Dave LaRonde Level 6

                                I don't know the ins and outs of AE to Premiere; I work in Final Cut Pro.  But if you use the expression Rick posted and you make sure the frame rates match, you should be good to go.

                                 

                                This whole credit roll thing isn't cut and dried; they get it wrong in Hollywood.  As evidence, look at the credits for JJ Abrams' version of Star Trek... ugh!

                                • 13. Re: AE 8 TEXT layer scroll creates text character jitter/flicker
                                  techinis Level 1

                                  Hi,

                                   

                                  "I hope this helps. Text rolls are never easy to perfect. Just watch the end of any movie on TV or in the theater. Some day I should do a tutorial on perfect text rolls."

                                   

                                  Indeed, do you have any AE file that you can make available for us to see all these details!

                                   

                                  I will then see if what I do and what we all explain here are te same...maybe I got my credit good for you but not for me. Thanks for your help