Graphical Perspective: Exploring Visual Perception in Computer Vision

By Fouad Sabry

What is Graphical Perspective

Linear or point-projection perspective is one of two types of graphical projection perspective in the graphic arts; the other is parallel projection. Linear perspective is an approximate representation, generally on a flat surface, of an image as it is seen by the eye. Perspective drawing is useful for representing a three-dimensional scene in a two-dimensional medium, like paper.

How you will benefit

(I) Insights, and validations about the following topics:

Chapter 1: Perspective (graphical)

Chapter 2: Leon Battista Alberti

Chapter 3: Leonardo da Vinci

Chapter 4: Luca Pacioli

Chapter 5: Masaccio

Chapter 6: Filippo Brunelleschi

Chapter 7: Piero della Francesca

Chapter 8: Renaissance art

Chapter 9: Vitruvian Man

Chapter 10: Holy Trinity (Masaccio)

(II) Answering the public top questions about graphical perspective.

(III) Real world examples for the usage of graphical perspective in many fields.

Who this book is for

Professionals, undergraduate and graduate students, enthusiasts, hobbyists, and those who want to go beyond basic knowledge or information for any kind of Graphical Perspective.

• Language: English
• Publisher: One Billion Knowledgeable
• Release date: May 5, 2024

Book preview

Chapter 1: Perspective (graphical)

In the visual arts, linear or point-projection perspective (from Latin perspicere, to see through) is one of two types of graphical projection perspective; parallel projection being the other. Linear perspective is an approximation, typically on a flat surface, of how the eye perceives an image. Perspective drawing is beneficial for depicting a three-dimensional scene on a flat surface, such as paper.

Objects appear smaller as their distance from the observer increases, and they are subject to foreshortening, which causes dimensions parallel to the line of sight to appear shorter than dimensions perpendicular to the line of sight. All objects will retreat to distant places, often along the horizon, but also above and below the horizon, depending on the viewpoint.

Italian Renaissance painters and architects such as Filippo Brunelleschi, Leon Battista Alberti, Masaccio, Paolo Uccello, Piero della Francesca, and Luca Pacioli studied linear perspective, authored treatises on it, and used it into their works of art.

Perspective is achieved by depicting the light that goes from a scene via an imagined rectangle (the picture plane) to the viewer's eye, as if the spectator were gazing through a window and painting directly onto the windowpane. If viewed from the same location as when the windowpane was painted, the painted image and the view through the unpainted window would be identical. Thus, each painted object in the picture is a flat, reduced representation of an object on the other side of the window.

Examples of one-point perspective

Examples of two-point perspective

Examples of three-point perspective

Additionally, a central vanishing point can be utilized to express frontal (foreshortened) depth (as with one-point perspective).

Examples of curvilinear perspective

Many objects and people in the earliest paintings and sketches were scaled according to their spiritual or thematic significance, not their distance from the observer, and no foreshortening was used. The most important figures are frequently depicted at the top of a composition, also from hieratic motives, resulting in the so-called vertical perspective prevalent in Ancient Egyptian art, in which a group of nearer figures is shown below the larger figure or figures; simple overlapping was also used to relate distance.

It is generally agreed that between 1415 and 1420, Filippo Brunelleschi conducted a series of tests, which included correct perspective drawings of numerous Florentine buildings.

This situation is illustrative, but has numerous challenges.

First and foremost, Regarding the view from San Giovanni's baptistery, nothing can be said with certainty, due to the loss of Brunelleschi's panel.

Second, There is no other known perspective painting by Brunelleschi.

Third, Brunelleschi's panel was described by Antonio di Tuccio Manetti at the end of the 15th century, There is not one instance of the term experiment.

Fourth, The conditions enumerated by Antonio di Tuccio Manetti are incompatible.

For example, the description of the eyepiece sets a visual field of 15° much narrower than the visual field resulting from the urban landscape described.

Immediately following Brunelleschi's demonstrations, practically every artist in Florence and Italy employed mathematical perspective in their paintings and sculptures, This overarching narrative is based on qualitative judgements and would need to be weighed against the empirical evaluations of Renaissance perspective paintings. Except for the paintings of Piero della Francesca, which serve as a model for the genre, the majority of works from the 15th century contain significant geometric mistakes. True of Masaccio's fresco of the Trinity

In the 1470s, Piero della Francesca developed on De pictura in De Prospectiva pingendi, including numerous references to Euclid.

Perspective images are formed with a certain center of view for the picture plane as the reference point. For the final image to appear identical to the original scene, the observer must observe it from the exact vantage point utilized in the calculations. When viewed from a different vantage point, this eliminates any apparent image distortions. For instance, a perspective-drawn sphere will be stretched into an ellipse. As the angle between a projected ray (from the scene to the eye) and the picture plane grows more sharp, these apparent distortions become more evident as one moves away from the image's center. Artists might fix perspective errors by, for instance, depicting all spheres as perfect circles or painting figures as if centered on the direction of view. In actuality, unless the spectator is observing the image from an extreme angle, such as standing to the side of a painting, the perspective usually appears accurate. This phenomenon is known as Zeeman's Paradox..

{End Chapter 1}

Chapter 2: Leon Battista Alberti

Leon Battista Alberti (Italian: [leˈom batˈtista alˈbɛrti]; 14 February 1404 - 25 April 1472) was an Italian humanist author of the Renaissance, artist, architect, poet, priest, linguist, philosopher, and cryptographer; He exemplified the characteristics of contemporary polymaths.

He is regarded as the originator of Western cryptography, A claim that he and Johannes Trithemius share.

Giorgio Vasari's Lives of the Most Excellent Painters, Sculptors, and Architects recounted Alberti's life.

In 1404, Leon Battista Alberti was born in Genoa. Bianca Fieschi is his mother. Benedetto Alberti, his father, was a wealthy Florentine who had been exiled from Florence but was allowed to return in 1428. Alberti attended boarding school in Padua and subsequently law school in Bologna.

In 1446, he received his first significant architectural project for the facade of the Rucellai Palace in Florence. This was followed in 1450 by Sigismondo Malatesta's mandate to convert the Gothic church of San Francesco in Rimini into the Tempio Malatestiano, a memorial chapel. The only known sculpture of Alberti is a medallion of self-portrait, which is frequently credited to Pisanello.

Alberti was commissioned to design two churches in Mantua: San Sebastiano, which was never completed, and the Basilica of Sant'Andrea, the intent of which can only be conjectured. The design for the latter church was completed a year before Alberti's death in 1471;