Surface Size

Is it possible to determine the actual size of a surface in pixels?
When I project a clip onto a Surface, the resolution depends on the resolution of the projector. In order to optimize the computing time for clips in advance, it would be great if I could determine the resolution used by the projector.
e.g. The projector use 1920 * 1080 Pix
The Surface is a stage element with the size 3m * 4m.
The distance of the projector is 8m and the angle from the projector to the surface is approx. 38 degrees.
When I should "calculate" my head bursts.
I would like to map a surface to the stage element and then read out the real size in millimeter pixels.
Is that possible?

Comments

  • Sorry, there is a translation error.... Again:
    Is it possible to determine the actual size of a surface in pixels?
    When I project a clip onto a Surface, the resolution depends on the resolution of the projector. In order to optimize the computing time for clips in advance, it would be great if I could determine the resolution used by the projector.
    e.g. The projector use 1920 * 1080 Pix
    The Surface is a stage element with the size 3m * 4m.
    The distance of the projector is 8m and the angle from the projector to the surface is approx. 38 degrees.
    When I should "calculate" my head bursts.
    I would like to map a surface to the stage element and then read out the real size inside millumin in pixels.
    Is that possible?
  • Hello @Peter2020,

    I'm not sure to understand your question.
    Have you tried to rather use "pixel constraint" (click on the "cog" button next to the scale property) ?

    Best. Philippe




  • Hello Philippe,
    thank you for the fast response. It takes hours to find the option pixel constraint. You only can use it, when you
    don't tough the vertices. This is not realy what I am looking for.
    I apologize that my description was so incomprehensible.
    I'll try it again. I am looking for a value that gives me the "media size used". (used media size)

    I took the liberty of making a sketch, a front view and a top view.

    When I map a clip onto the stage element, Millumin scales the material. It's a good thing.

    1. If Millumin scales a Full HD clip onto this element, this is wasted time in pre-production. It would be less time consuming to calculate a clip in the (approximate) resolution. The collaboration between Millumin and After Effects can also save computing power if the animation has a lower resolution.

    2. Stage elements are not always exact. A projection area of ​​4: 3 can sometimes be delivered from
    the workshops to 4.5: 2.7. If I now map a pre-produced 4: 3 clip onto this surface, everything is distorted. I can eliminate the distortion with millumin, but the image detail is not original. Especially with projections that have a frame within the projection, unsightly results come out.

    Possible (semi-optimal) solution:
    I discovered a "workaround" in Millumin. When I double-click the corner points when setting up a Surface, Millumin shows me the coordinates. With the help of simple calculations I can now calculate the "used media size".

    maybe there is a better solution or a button that I have to discover first ....

    Best Peterimageimage

    image
    Frontview.png
    1920 x 1080 - 379K
    Topview.png
    1920 x 1080 - 73K
  • Hello @Peter2020,

    You're pointing out 2 different problems :
    - optimizing the size of your rendered movie (because you project less pixels than expected)
    - fixing the ratio of the movie, because the projection surface doesn't match it


    First problem : don't over-optimize the size.
    Rather choose between standard resolutions. I mean choose 720p if 1080p is too much, choose 1080p if 2160p is too much. Don't end up with movies having weird sizes such as 1333x1000.
    In brief : be rough about the sizes asked to content producers, and always be higher (soif your videoprojector moves, you still have some pixels to adjust !).
    However, use good codecs such as HAP, this can have more incidence on performances than resolution ! More info on this post.

    Second problem.
    If the ratios of your movie and your surface are very different, you need to crop your content, so pixel ratio is perserved (the image doesn't look squashed). You can do so with the slice-editor (see this tutorial).
    To determine the exact amount of pixels you need to "cut", you need to know what is the exact ratio of your projection surface : the faster way is to measure it with a ruler. But you won't be able to determine it from Millumin, by just looking at the "bounding box" size of your layer. At least accurately.

    Best. Philippe
  • Hello,

    Why can't we use weird sizes ?

    Thanks

  • For performances, it shouldn't change anything.

    But presets for production and encoders are usually done with standard resolutions.
    Also from my point of view, it's better to work with a limited set of resolutions, because we quickly learn to masterise them, instead of having always different numbers to deal with.

    Best. Philippe
  • Thanks,

    Sometimes, I create my files with a non standard resolution, because I use the ratio of the surface. It is easier because I don't use any effect (soft crop, or slice editor) to match with my surface.

    Best !
  • Thank you for the answer.
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