add zoom translation space in FOV space

[mfournier-genetec]

This PR adds to Annex A a new space titled "Zoom Translation space in FOV". That new zoom space explains the concept of relative zoom translation space in graphical user interfaces for ptz cameras in relation to it's current FOV.

[Ekmansoft]

Am I understanding this correctly when I assume it is meant as follows:

1. We want to add a function that allows us to zoom in relative to the current zoom setting.
2. If we are using 1280x720 resolution and want to zoom in by doubling the focal length the value set would be 640/1280=0.5?
3. We would thus set TranslationSpace to 0.5.
4. We should zoom in and decrease FOV to half, and increase focal length?

Is this correct?

Not sure why the range need to be 0 to INF, since 0 to 1 should suffice if we only want to zoom in?

The function will not support any movement in pan- or tilt-spaces?

[jflevesque-genetec]

Am I understanding this correctly when I assume it is meant as follows:

1. We want to add a function that allows us to zoom in relative to the current zoom setting.
2. If we are using 1280x720 resolution and want to zoom in by doubling the focal length the value set would be 640/1280=0.5?
3. We would thus set TranslationSpace to 0.5.
4. We should zoom in and decrease FOV to half, and increase focal length?

Is this correct?

Not sure why the range need to be 0 to INF, since 0 to 1 should suffice if we only want to zoom in?

The function will not support any movement in pan- or tilt-spaces?

You forgot the inverse. If you zoom, it would be 1 / (640 / 1280) = 2

[kieran242]

I agree with the changes.

[HansBusch]

Honestly like the FOV suffix more than the existing Fov, but we can't change the existing one. Hence the suggestion to adapt.

[HansBusch]

Specification is fine. However I suggest to align the URI to the existing PT space http://www.onvif.org/ver10/tptz/PanTiltSpaces/TranslationSpaceFov with trailing lower case 'ov':

http://www.onvif.org/ver10/tptz/ZoomSpaces/TranslationSpaceFov