The Meaning
I grew up in New Mexico and am fond of Spanish. For example, I (with some help from my colleagues Loren Carpenter and Rodney Stock) created the name Pixar for my previous company as a pseudo-Spanish verblike noun meaning "to make pictures" (the infinitive in Spanish ends in -ar, -er, or -ir). The word altamira has fine Spanish meanings. The first half, alta, means "high". The second half is a form of the verb mirar, meaning "to look at, to gaze, to behold, to watch, to value, to think highly of, to regard, to consider, to aim, to have in mind". Thus altamira can mean many things, from "behold on high" or "high things to look at" - such as the paintings on the ceiling of the Cave of Altamira - to "high value", "high aims", and "high regard". Altamira, the company, took it to mean "high quality images".
Even the Indo-European roots are benign. The root for alta is al-, "to grow". From this came the Latin altus, "high", then the Spanish alta and such familiar English derivatives as altimeter, altitude, alto, enhance, exalt, and oboe (from French haut bois, "high wood"). The Indo-European root for mira is smei-, "to smile". From this came Old Latin mir-, "to look at (with wonder or astonishment)", thus causing one to smile, and Latin mirus, "astonishing, strange, wonderful". The Spanish mirar is derived from these as are the English words admire, marvel, mi (as in do-re-mi), miracle, mirage, mirror, and smile. In astronomy, star Mira (the Wonderful) is the protypical variable star.