14 Replies Latest reply on Aug 15, 2011 6:37 AM by Andrew Yoole

    Interlaced hell!

    AdobeLuvr007 Level 1

      Hello Adobe users.

       

      I am a professional motion graphic user, although strange I need to adress these issues.

      I have made about 300 motion graphics job that run on national TV and I have delivered them always in progressive SD quicktimes.

      Nobody complained about it and it seems fine on TV (no judder ect.) Propably because they import my SD uncompressed quicktimes into Avid/FCP and the system makes it interlaced.

       

      Recently I had some editors that only wanted SD interlaced footage and they cannot seem to handle the progressive files.

      No problem for me. I just render it out with Upperfields and deliver them. But I have seem some issues with jagged edges that are beyond the normal interlace/deinterlaced jagged edges.

       

      The problem is very apparent when you have an vector file and you rasterize it (collapse transformation button *) in aftereffects.

      When you render the animation with Upperfields and you review the footage interpreted as upper in aftereffects you really see very jagged edges.

      When you turn of rasterize or just replace it with an PSD (of the same  vector) you dont have that problem. I have tested it out many times and it seems to be a problem with the continue rasterisation proces. Is this a known bug or is there some kind of explenation?

       

      Also, it's normal to make interlaced footage progressive because if you scale/rotate/blur an interlaced file you will get strange effects and flicker.

      But if you have to add text/graphics to a real progressive file (from alexa/red or renders from a 3D package) and you render this out as interlaced footage you are basicly rendering the text/graphics out as 50 different fields (like it should be) but the progressive footage does not have those fields, you are just showing frame 1 two times both Upper/Lower, frame 2 two times ect.. ect.. So you are mixing a very fluent text/graphics animation with an progressive file that has been interlaced (without having real 50 different frames). What is the solution for this? Render it all out progressive, reimport and render out that movie in interlaced? Because making the progressive footage into interlaced, than deinterlace it in AE and render out in fields, you are decreasing the quality of the footage alot! This drives me crazy

       

      Two quick examples. The file is a illustrator vector.

      In the first example the vector is 100% size, footage rendered out in fields and reimported in AE. Screens taken from AE. The compsize is 720x576 widescreen pal. I took screenshots without even previewing it stretched out to widescreen, because it gets a lot worse even. This is a raw pixels comparison. I scaled the example up 200% so you see the difference a little bit better.

      [IMG]http://i51.tinypic.com/ztao0m.jpg[/IMG]

       

      The second example shows the vector sized to 270% with continued rasterize ON. Also rendered out in fields and reimported with upper fields interpreted. Compsize is 1024x576 square pixels, so there is no added stretching of the footage involved.

      http://oi51.tinypic.com/m9ybmv.jpg

        • 1. Re: Interlaced hell!
          Rick Gerard Adobe Community Professional & MVP

          First of all it's very difficult to tell with an interlaced file will look like when played back when you're looking at it on a computer monitor. The artifacts may go away or they may be worse. You really can't make a judgement call unless you're playing back to an interlaced monitor. You cannot judge the quality of a paused still. You can make a guess, but it will only be a guess.

           

          Secondly, when you bring interlaced footage back into AE and select separate fields you are not going to get the same results as vector artwork. You're comparing apples and oranges. You can improve the look of interlaced footage by choosing one of several options or by using a 3rd party plug-in to separate the fields.

          • 2. Re: Interlaced hell!
            AdobeLuvr007 Level 1

            I know it is hard to judge an interlaced file but if you just see how jagged the edges are you will know you will also see some of it (maybe not as strong) on a field monitor.

             

            I just had a client today say that the text and video did not appear crisp. While i'm only exporting it as Upper. The footage I got from them was Upperfield, so I deinterlaced it in AE, added the fx and text animations and exported it back.

            • 3. Re: Interlaced hell!
              Andrew Yoole MVP & Adobe Community Professional

              When you interpret footage with fields within AE, it only displays one field of that footage during previews.  That's what you're seeing in the images you've posted - deinterlaced footage.  So long as your final render is interlaced, After Effects will use one field of source footage per field of output, so there won't be an issue.  If you render progressive, but have field-interpreted source material, that material will end up deinterlaced, so it will look soft.

              • 4. Re: Interlaced hell!
                AdobeLuvr007 Level 1

                But supposedly AE should make a full frame from 2 field frames.

                So why doesnt it show the full frame on full preview?

                 

                If I have interlace footage that I interpret just for playback or even keying I dont have any problems it has full resolution and the picture is progressive.

                • 5. Re: Interlaced hell!
                  Mylenium Most Valuable Participant

                  But supposedly AE should make a full frame from 2 field frames.

                   

                  It doesn't and it never did. Unless you apply specific filters or techniques to reconstruct the data from the horizontally offset interlace lines, all you see is either both fields at the same time with field interpretation set to none or only one field, effectively only half the vertical resolution. Using continuous rasterization or not has no effect on this underlying basic principle, but there may be other things involved here because naturalyl using CR also has other uses and purposes and affects the render order. For everything else you are merely overthinking the whole matter with regards to mixing progressive and interlaced sources. True, sometimes it will just look choppy, but you can't defaet the math and physics. For everything else there is nothing wrong with a bit of motion blur and making sure to use a correct composition shutetr setting as there is nothing wrong with synthesizing fields using tools like RevisionFX' FieldsKit (or in reverse, get rid of fields).

                   

                  Mylenium

                  • 6. Re: Interlaced hell!
                    Andrew Yoole MVP & Adobe Community Professional

                    Note also that the demo pics you've posted - thin black lines on white - are the worst kind of content to create in interlaced video.  Thin high contrast lines are nightmares when working with interlaced video.  Expect to use some softening tools, such as Blur/Reduce Interlace Flicker, to deal with the inevitable flicker that such lines cause on interlaced monitors.

                    • 7. Re: Interlaced hell!
                      AdobeLuvr007 Level 1

                      It is such a difficult matter. I mean I have made a full national TV styling in progressive SD and it works fine and looks very good on TV.

                      And when I deliver something for the same tvstation and there is a tough freelance editor that only wants interlaced I dont get it.

                      The problem is that I dont know how AVID works (90% work on avid and I deliver meridean quicktimes). I guess the 'preset' they use is an PAL SD widescreen with upperfields as a standaard. So what happens when they import my progressive quicktime? Do they have to interpret it as an progressive and Avid does the rest or can't you mix progressive in an interlaced enviroment?

                       

                      Than I'm wondering how the hell they process Red/Alexa files? They are also progressive and broadcast just fine!

                      I think its just the editor that is being difficult. Because like I says 90% of the 300 movies graphic movies I delivered to the stations were progressive.

                      Never ever had any problems.

                      • 8. Re: Interlaced hell!
                        Rick Gerard Adobe Community Professional & MVP

                        The only difference between interlaced and progressive when the standard is NTSC or PAL for broadcast is that progressive video has two identical fields. It's still sent over the airwaves as an interlaced signal. It has to be because NTSC and PAL are both interlaced (pairs of fields maked a frame) formats. Film that's transferred to NTSC or PAL have pairs of identical fields. NTSC adds a 3:2 cadence to these identical fields that give you one funky frame in 3. There's no reason, technically, that delivering a progressive render to a broadcaster would cause a technical problem.

                         

                        There is a difference on how motion looks. There is a difference in acceptable panning speeds. Thin lines flicker more with movement when the video is interlaced. Camera moves horizontally and vertically tend to get the judders or strobe with progressive video, but those are artistic and not technical problems.

                         

                        I don't know if this helps you at all. Most people, especially folks that have never worked with film for video or linear editing equipment or for a broadcaster before computers ran everything don't have a clear understanding of interlacing.

                        • 9. Re: Interlaced hell!
                          AdobeLuvr007 Level 1

                          It helps a bit.

                          The problem is telling it to an editor who has been doing this 20+ years.

                          In times were there wasn't progressive footage for TV.

                          Nowadays you have REd/Alexa's/DSLR's ect. All feeded into the TV broadcast system.

                          So like I already thought. Basicly its the editor that is being hard or maybe not understanding how to 'import' the progressive files?

                          • 10. Re: Interlaced hell!
                            AdobeLuvr007 Level 1

                            I was also wondering.

                            Since Avid v5 i'm (finally) getting 1024x576 squarepixel quicktimes from editors. Maybe because they added this export feature or it is standard now? (dont know Avid that well).

                             

                            Normally I also make everything in 1024px squared. It gives some extra resolution in AE, no need to stretcht to widescreen.

                            But will it give me better resolution/results when exporting to PAL SD? I think it is gonna be the same right?

                             

                            Working with squarepixels in AE is just nicer, no interpolation needed.

                            • 11. Re: Interlaced hell!
                              Rick Gerard Adobe Community Professional & MVP

                              You don't have to do anything to import progressive files. Nothing at all. The fields are just duplicates.

                              • 12. Re: Interlaced hell!
                                AdobeLuvr007 Level 1

                                Ok. They tell me the text/graphics are okay.

                                The main problem is the quality of the movie.

                                 

                                I have noticed this to in AE.

                                When you have an interlaced footage, you interpret it to progressive in AE, render it out (without even applying FX) you will get a MUCH less sharp movie!

                                Even looks like you didt some kind of 1px or 2px blur on the whole movie.

                                 

                                I dont see what I can do about that?

                                Working interlaced (not interpreting) is not an option when you need to scale/rotate the footage.

                                Sigh...

                                • 13. Re: Interlaced hell!
                                  Andrew Yoole MVP & Adobe Community Professional

                                  I'll spell all this out with specifics to make it clear:

                                   

                                   

                                  If you interpret interlaced footage appropriately, then render with fields, input and output should be unchanged.  It should look basically identical.

                                   

                                  If you interpret interlaced footage appropriately, but render progressive, your source footage will only contain one field - it will look soft.  After Effects doesn't really have any tools built in to combat this issue.  There are third party plugins that create interpolated progressive frames from interlaced footage, such as Magic Bullet Frames.

                                   

                                  If you interpret progressive footage correctly, and render progressive, input and output should be unchanged.  It should look basically identical.

                                   

                                  If you interpret progressive footage correctly, and render with fields, your progressive footage will remain progressive, but any animation that's generated by After Effects will be interlaced.  This sometimes creates an odd mismatch, especially if you are trying to composite items into a consistent single environment.  Personally, if I am working with predominantly progressive source footage, I render my output as progressive as well.  It's possible to re-interpolate fields into progressive footage (using the built in Timewarp features of After Effects, or third party plugins like Twixtor.  But this is a pretty rare request.  I suspect your Editor isn't demanding such extreme measures, and there's some misunderstanding between you both about what's required.

                                  • 14. Re: Interlaced hell!
                                    AdobeLuvr007 Level 1

                                    Wow. thanks that clears things up a bit.

                                    Am I missing this info from the manual or overlooked it?

                                    It is a BIG shame AE isnt capable of making a progressive full frame from interlaced video!

                                    What is up with that? This should be the holy grail of videoprocessing.

                                     

                                    "if you interpret progressive footage correctly, and render with fields,  your progressive footage will remain progressive, but any animation  that's generated by After Effects will be interlaced. "

                                     

                                    This is just tested out, i really thought it made the progressive also interlaced but it seems it does not.

                                     

                                    Thanks for the info.

                                    So basicly if I get interlaced footage (no progressive available) I should leave it to NONE in AE and use fieldskit of Magicbullet frames to make it progressive?