Vertical Video - makes my head hurt

mark_m

I have a video camera that I will turn on its side to capture in portrait (vertical) orientation.

I will feed that into Isadora via HDMI capture. The image will be HD (1920 x 1080) and in landscape orientation.
So I need to rotate that image 90 degrees so that it matches the orientation of the camera. I will use this image across lots of scenes.

I thought I would go:

video in watcher to projector to a virtual stage.
Make the virtual stage 1080 x 1920 px
Spin the projector 90 degrees
Use Get Stage Image of virtual stage to bring the rotated image in the correct orientation into my scenes.

However, my camera input on the virtual stage does not fill that 1080 x 1920 px stage: I have to zoom in to 175% on the virtual stage's projector to make it do so.
I think this is affecting the image quality.

I tried this:

video in watcher to projector to a virtual stage.
Make the virtual stage 1080 x 1920 px
Spin the projector 90 degrees.
In the projector turn OFF keep aspect
change height to 55% and width to 178
Use Get Stage Image of virtual stage to bring the rotated image in the correct orientation into my scenes.

So this works better, but is this having an effect on image quality too?

OR am I missing something very, very obvious?!

Here's the project file for anyone curious...

vertical-video.zip

Or a link to the Isadora file in Dropbox:

https://www.dropbox.com/scl/fi...

Thank you all!

Mark (no....)

dbini

Hi Mark, yeah, vertical video is a pain. i think you can fix the scaling issue in Izzymap. Set up a Virtual Stage with resolution 1080x1920, feed your video capture into this. Open IzzyMap in the virtual stage and change the output (bottom right) to Custom: 1080x1920, and rotate your output slice. It should then give you a full res vertical unscaled output from Get Stage Image.

jfg

jfg

I think the problem is coming from the change you made to the virtual stage. Leave the Virtual Stage at its original resolution (1920x1080) and you’ll only need to zoom out, which results in less loss of quality.

video in watcher to projector to a virtual stage.
Make the virtual stage 1920 x 1080 px
Spin the projector 90 degrees.
In the projector turn OFF keep aspect
change zoom to ±55% ~~and width to 178~~
Use Get Stage Image of virtual stage to bring the rotated image in the correct orientation into my scenes.

Best regards

Jean-François

mark_m

@dbini

Thank you, this seems to work well, and gives me the full 1920px height which I can scale as I like, but the scaling, I think, only happens once...

mark_m

@jfg

Thank you. So I think the problem with this approach is that my input gets scaled down to 55%, so the 1920px full resolution height that I'm looking for gets scaled down, becoming effectively 1080px, and if I scale the output again for output I have a double scaling issue going on, which I think can't be good for the resolution of the final output image. BUT I will test, thank you.

jfg

@mark_m

I don't understand, why you want to scale a second time or it is because you want use a different scaling for each scene?

scaling.izz

mark_m

@jfg said:

different scaling for each scene?

Yes, Jean-François, this is what I want to be able to do.

I'll use this camera's feed in a number of different ways throughout the performance, and at different scalings, sometimes even within the same scene.

For example, there will be one scene which lasts about 5 minutes, where we see the live image projected in the centre of the screen at about 66% original size, but there will also be a thumbnail image of the feed captured every 20 seconds, which will gradually fill up across the the top of the screen so that after five minutes we can see see 15 images that show how what's in front of the camera has changed since the start of the scene. These will be at maybe 10% of the original size.

But I am ignorant of the way that scaling works in Isadora. If you scale, then rescale, then rescale again, is the image going to deteriorate with each rescaling - like photocopying a photocopy, or is Isadora smarter than that?

Thank you for your time looking at this for me.

@dbini and also you for your time, John!

jfg

@mark_m said:

But I am ignorant of the way that scaling works in Isadora. If you scale, then rescale, then rescale again, is the image going to deteriorate with each rescaling - like photocopying a photocopy, or is Isadora smarter than that?

Sorry, I also don't know how Isadora deals with scaling. I think you will get an answer from someone on the team.

Best regards

Jean-François