The ST is trying (with minimal success...) to explain that the "aspect ratio" (=AR = ratio of width to height) of the logo, when displayed, must always be the same, regardless of the inherent aspect ratio of the support. IOW, the logo must never be stretched/compressed to a different extent in the vertical and horizontal directions. If the logo is supposed to be "square" (AR = 1), it must be displayed as "square" on any support, eg an old-fashoned TV screen with AR = 4:3, an HDTV screen with AR=16:9, a computer screen with AR = 14:9, etc.

Useage in the ST could be:
La modulación asegura la correcta proporción de un elemento sobre cualquier soporte y medida*
-->
Aspect ratio control will ensure correct display of an element on any support or media / regardless of size

* I'm wondering if this is a typo in Spanish: media or medida ... ?


El logotipo ... se enscribe en una superFIice modular de 1x en la dimensión vertical y 8x en la dimensión horizontal.
-->
The ... logo fits in a box with an aspect ratio of 8:1.

Especially in the second example, I hope you are charging your client per source word :)

Source: personal professional experience, especially in multi-format TV/computer display systems, as well as print media.