10 Replies Latest reply on Dec 4, 2009 1:32 PM by HarryPutnam

    Transfer rotoscope path to different layer

    HarryPutnam Level 1

      A novice rotoscoper, I got a little confused from having read and watched tutorials with several diffeent styles of rotoscoping.

       

      Some said to use a layer in between path and actual subject layer with the eyeball turned off.  Then lock the actual target layer so as not to move it around inadvertantly.

       

      I may have that confused a bit... if so, it not the tutorials doing but mine.

       

      Cutting to the chase; I have a solid light grey layer with the opacity turned down to 1. above a footage layer of my great grandson doing his first zombie walk.

       

      I spent a lot of time getting a mask to follow his little head in his trek across the floor.  Now I wanted to transfer the mask path points over to the target footage layer.  I clicked the footage layer with the pen tool to get a mask started, then with focus on the grey layer/Mask/mask path (all the points are lit up so selected) and copy... then to the footage layer Mask/Mask path - paste.  So far so good.

       

      But somehow I must have moved either the grey solid layer or the footage layer sometime during all the pulling and hauling.so the mask misses the head in a perfect offset all the way thru.  The attached screen shot illustrates it well.  The first one shows the mask on the grey layer, the second on the footage layer.

       

      I tried lining up the layers by setting the `position' parameters the same, also by just eyeballing the crosshair thing that shows the center of each layer.

      Trouble is I can't find a way to see the crosshair from the one layer as soon as I focus on the other to move it.  Ditto for the path itself.  Soon as focus changes the path does to.  I may be going the opposite way of what I should, but tried it both ways with both layers and am just not getting how to get it right.

       

      I know I can just do it over, and that isn't really a problem since I can clearly use the practice.  But I feel like there must be a a clearcut way to match up a layers position to a path.

       

      At this point I've thoroughly confused the heck out of myself and would like to hear someone lay out how to get two layers to match up

        • 1. Re: Transfer rotoscope path to different layer
          HarryPutnam Level 1

          Darn it, the message got away before I got the images attached...I thought there was a way to edit ones post here but I see no `Edit' switch anywhere so here are the Images showing the offset of the mask from one layer to another:

           

          First: The solid gray layer with opacity down to 1 where I actuall drew the mask:

          grey_off-layer.png

           

          Next the the offset that occurs when pasting the mask positions to the actual footage layer:

          (How to line it up so painstaking mask is lined up?)

           

          footage_ON_layer.png

          • 2. Re: Transfer rotoscope path to different layer
            Andrew Yoole MVP & Adobe Community Professional

            So long as it's offset consistently, the solution is simple.

             

            Position the current time indicator on any one of the pasted mask keyframes on your main subject layer.  Select all the keyframes by clicking on Mask Path in the left column of the timeline.  Then simply drag the mask shape into position around the head.  All the selected keyframes will be offset equally by the adjustment.

            • 3. Re: Transfer rotoscope path to different layer
              Adolfo Rozenfeld Adobe Employee

              If you wanted to paste the mask from the solid into a footage layer, you need to make sure the solid is the same size as the footage layer (and that that the scale values are the same). If the solid is larger or smaller than the footage item, or if the footage item is scaled in any way, the mask won't appear in the same relative location when pasted.

              However, I think the whole point of making the mask in a solid layer above is NOT pasting the mask, but using the transparency in the solid to punch a hole in ethe footage layer. A Track Matte does exactly that - it masks a layer using the alpha or luminance values of another layer.

              To do this, you need to make sure that the the layer that's going to be "punched" sits immediately below the "punching" layer (in this case, this is happening, but remember it's a requirement) and then:

               

              1. Press the Toggle Switches/Modes button so that the timeline shows blend modes and Track Matte controls instead of switches.

              Toggle.png

               

              2. Set the footage layer's Track Matte controls to "Alpha Matte".

              TrkMat.png

               

               

               

              For more information on track mattes, see Track mattes and traveling mattes in After Effects Help.

              • 4. Re: Transfer rotoscope path to different layer
                HarryPutnam Level 1

                Andrew Yoole wrote:

                 

                So long as it's offset consistently, the solution is simple.

                 

                Position the current time indicator on any one of the pasted mask keyframes on your main subject layer.  Select all the keyframes by clicking on Mask Path in the left column of the timeline.  Then simply drag the mask shape into position around the head.  All the selected keyframes will be offset equally by the adjustment.

                If that works for you then there is something else wrong here.  I  tried that very thing before posting but what happens is that as soon as I release the mask the hilighted keyframes go unlighted... accept for the one the CTI is on.   So its the only one that gets the right stuff.  If I move to the next keyframe the mask is out of place by the offset again.

                 

                Followed you recipe up to the point of moving mask:

                All_Select.png

                 

                Then drag the mask into place and release.. note how only 1 keyframe is now selected:

                 

                Released.png

                 

                And finally move to next keyframe and mask is offset again:

                nosoap.png

                • 5. Re: Transfer rotoscope path to different layer
                  HarryPutnam Level 1

                  Adolfo Rozenfeld wrote:

                   

                  If you wanted to paste the mask from the solid into a footage layer, you need to make sure the solid is the same size as the footage layer (and that that the scale values are the same). If the solid is larger or smaller than the footage item, or if the footage item is scaled in any way, the mask won't appear in the same relative location when pasted.

                  However, I think the whole point of making the mask in a solid layer above is NOT pasting the mask, but using the transparency in the solid to punch a hole in ethe footage layer. A Track Matte does exactly that - it masks a layer using the alpha or luminance values of another layer.

                  To do this, you need to make sure that the the layer that's going to be "punched" sits immediately below the "punching" layer (in this case, this is happening, but remember it's a requirement) and then:

                   

                  1. Press the Toggle Switches/Modes button so that the timeline shows blend modes and Track Matte controls instead of switches.

                  Toggle.png

                   

                  2. Set the footage layer's Track Matte controls to "Alpha Matte".

                  TrkMat.png

                   

                   

                   

                   

                   

                  Doggone it, I new I was forgetting some whole aspect of the proecess.  But following your advice; What should I see then?  What I actually do see is all black.  Then if I select the mask path, it appears on an all black background. so both inside and outside the mask are black.

                  • 6. Re: Transfer rotoscope path to different layer
                    Adolfo Rozenfeld Adobe Employee

                    Is the footage layer below turned on?

                    What you should see is as if the mask was applied to the footage layer, even if it's in the solid layer above. A track matte set to Alpha uses the transparency in the layer above to mask out the layer below (the one in which you assign the track matte mode).

                     

                    If you want send me the After Effects project as you have it now (no need for source files, just the project) to arozenfe( )adobe.com and I'll take a look.

                    Of course change ( ) for @.

                    • 7. Re: Transfer rotoscope path to different layer
                      Mylenium Most Valuable Participant

                      If I may be so bold... If the mask is offset by a fixed amount all the time, using the KeyTweak script might offer a quick and easy way to fix it. just look it up on aescripts.com.

                       

                      Mylenium

                      • 8. Re: Transfer rotoscope path to different layer
                        HarryPutnam Level 1

                        Adolfo Rozenfeld wrote:

                         

                        Is the footage layer below turned on?

                        What you should see is as if the mask was applied to the footage layer, even if it's in the solid layer above. A track matte set to Alpha uses the transparency in the layer above to mask out the layer below (the one in which you assign the track matte mode).

                         

                        If you want send me the After Effects project as you have it now (no need for source files, just the project) to arozenfe( )adobe.com and I'll take a look.

                        Of course change ( ) for @.

                         

                        Haa, the footage layer is turned on but the solid layer above was set to 1% opacity.. with the eyeball off. cranking that up 100 fixed it.  Now I can see the babies head, and the rest is masked out as expected.

                         

                        You'd think the opacity setting on the solid layer would not matter if the layer eyeball is off anyway, but apparently it does.  If I scroll the opacity up and down with the layer eyeball off,  the babies head appears at higher percentages and disappears below 10 or so.

                         

                        Thanks for the kind offer and for the good coaching.

                         

                        I'd also made another error... there is a little checkbox just ahead of the trackmatte drop down on the latyer controls.

                         

                        The column is headed with `T'  and when you check it, it says `preserve transparency'.  I don't quite get what that is for.

                         

                        However, if I check it, then all is black.  And I had checked it at first, thinking that was how you turned the matte on.

                        Unchecked I see the babies head as expected.

                         

                        Another aspect of this:  I wanted to rotoscope the whole body... so as to be able to insert it on differnet backgrounds.

                        I could use some ideas on that too.  I started with just the head to get an idea of how its done... but I'm guessing it might be easiest done by taking several masks to enclose various chunks of the babies body.   Is that how its done?

                         

                        You can see the footage here: zombie walk.

                         

                        Gack sorry... I Forgot that is passworded.... try it now if you received a password prompt

                        • 9. Re: Transfer rotoscope path to different layer
                          Adolfo Rozenfeld Adobe Employee

                          Haa, the footage layer is turned on but the solid layer above was set to 1% opacity.. with the eyeball off. cranking that up 100 fixed it.  Now I can see the babies head, and the rest is masked out as expected.

                           

                          You'd think the opacity setting on the solid layer would not matter if the layer eyeball is off anyway, but apparently it does.  If I scroll the opacity up and down with the layer eyeball off,  the babies head appears at higher percentages and disappears below 10 or so.

                          If you think about it, it makes sense.

                          A track matte set to "alpha" applies the opacity value of each pixel in the layer directly above to current layer. So, if Opacity for that layer is 1 per cent, that affects the opacity value of all pixels. Leaving it at 100 per cent, means that fully opaque pixels are applied as fully opaque, and fully transparent pxiels as fully transparent.

                          The visibily control (eyeball) for the layer above is turned off aumatically (if it's not already off) as soon as you set a track matte mode. So, the layer is "seen" for the operation regardless of the visibiliy status.

                           

                          The column is headed with `T'  and when you check it, it says `preserve transparency'.  I don't quite get what that is for.

                          That's called "Preserve Underlying Transparency", and it's a very convenient option... but I am surprised by how many people enable it without knowing what it does. It's not the first time someone gets bitten by it

                          And what it does is... this layer (the one with the switch turned on) only exists in areas that are not transparent, when taking into account the combination of all layers below. Example: if you have three circles placed in different places, and then create a large text layer and enable this switch, text will only exist in places that match the circles underneath.

                          More info in Preserve underlying transparency during compositing, in After Effects Help on the web.

                           

                           

                          Another aspect of this:  I wanted to rotoscope the whole body... so as to be able to insert it on differnet backgrounds.

                          I could use some ideas on that too.  I started with just the head to get an idea of how its done... but I'm guessing it might be easiest done by taking several masks to enclose various chunks of the babies body.   Is that how its done?

                          There are many valid approaches, and whatever works for you is fine. But you can be happy to learn that many experienced roto artists suggest doing exactly as you just described

                          I really recommend Mark Christiansen's book After Effects CS4 Visual Effects and Compositing Studio Techniques. It has a lot of useful information on roto work with AE.

                          • 10. Re: Transfer rotoscope path to different layer
                            HarryPutnam Level 1

                            Adolfo Rozenfeld wrote:


                            There are many valid approaches, and whatever works for you is fine. But you can be happy to learn that many experienced roto artists suggest doing exactly as you just described

                            I really recommend Mark Christiansen's book After Effects CS4 Visual Effects and Compositing Studio Techniques. It has a lot of useful information on roto work with AE.

                            I did go ahead and splurge on that book and got the electronic version too for $16 more.  I've seen that fellow, Mark,before on an AE Tutorial from Adobe TV.   Also about rotoscoping... but a fair bit different than what I'm currently doing.

                             

                            HERE

                            In case anyone is interested