Cropping (image)

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Cropping is the removal of unwanted outer areas from a photographic or illustrated image. The process usually consists of the removal of some of the peripheral areas of an image to remove extraneous visual data from the picture, improve its framing, change the aspect ratio, or accentuate or isolate the subject matter from its background. Depending on the application, this can be performed on a physical photograph, artwork, or film footage, or it can be achieved digitally by using image editing software. The process of cropping is common to the photographic, film processing, broadcasting, graphic design, and printing businesses.

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In photography, print, and design

Wide view, uncropped photograph Vinepyrennees.jpg
Wide view, uncropped photograph
Cropped version, accentuating the subject Vinepyrennees crop.jpg
Cropped version, accentuating the subject

In the printing, graphic design and photography industries, cropping is the removal of unwanted areas from the periphery of a photographic or illustrated image. Cropping is one of the most basic photo manipulation processes, and it is carried out to remove an unwanted object or irrelevant noise from the periphery of a photograph, change its aspect ratio, or improve the overall composition.

In telephoto photography, most commonly in avian and aviation photography, an image is cropped to magnify the primary subject and further reduce the angle of view. When a lens of sufficient focal length to achieve the desired magnification directly is not available. It is considered one of the few editing actions permissible in modern photojournalism along with tonal balance, color correction and sharpening. A cropping made by trimming off the top and bottom margins of a photograph, or a film, produces a view that mimics the panoramic format (in photography) or the widescreen format in cinematography and broadcasting. Neither of these formats is cropped as such, but rather they are products of highly specialized optical configurations and camera designs.

Graphic examples (photography)

Cropping in order to emphasize the subject:

Cropping in order to remove unwanted details/objects:

Crop marks

Visiting card before and after cropping. Cropped card.jpg
Visiting card before and after cropping.

To assist in precise cropping of a printed image, crop marks may be printed at the four corners of the image, just outside the central area to be retained: at the top left corner, at the top right corner, at the bottom left corner, and at the bottom right corner. The paper or paperboard on which the image is printed can then be cut on each side so that the crop marks are removed.

In Unicode, the crop marks are represented by:

Crop marks are useful for cropping images printed with bleed, and more generally, when the position of an image on the final sheet is not precisely known in advance.

In cinematography and broadcasting

In certain circumstances, film footage may be cropped to change it from one aspect ratio to another, without stretching the image or filling the blank spaces with letterbox bars (fig. 2).

Concerns about aspect ratios are a major issue in filmmaking. Rather than cropping, the cinematographer usually uses mattes to increase the latitude for alternative aspect ratios in projection and broadcast. Anamorphic optics (such as Panavision lenses) produce a full-frame, horizontally compressed image from which broadcasters and projectionists can matte a number of alternative aspect ratios without cropping relevant image detail. Without this, widescreen reproduction, especially for television broadcasting, is dependent upon a variety of soft matting techniques such as letterboxing, which involves varying degrees of image cropping (see figures 2, 3 and 4). [1]

Since the advent of widescreen television, a similar process has removed large chunks from the top & bottom to make a standard 4:3 image fit a 16:9 one, losing 25 percent of the original image. Another option is a process called pillarboxing, where black bands are placed down the sides of the screen, allowing the original image to be shown full-frame within the wider aspect ratio (fig. 6).

Additional methods

Various methods may be used following cropping or may be used on the original image.

Digital images

It is not possible to "uncrop" a cropped digital image unless the original still exists or undo information exists: if an image is cropped and saved (without undo information), it cannot be recovered without the original.

However, using texture synthesis, it is possible to artificially add a band around an image, synthetically "uncropping" it. This is effective if the band smoothly blends with the existing image, which is relatively easy if the edge of the image has low detail or is a chaotic natural pattern such as sky or grass, but does not work if discernible objects are cut off at the boundary, such as half a car. An uncrop Archived 2010-01-22 at the Wayback Machine plug-in exists for the GIMP image editor.

See also

Related Research Articles

<span class="mw-page-title-main">Letterboxing (filming)</span> Black bars below and above an image

Letter-boxing is the practice of transferring film shot in a widescreen aspect ratio to standard-width video formats while preserving the film's original aspect ratio. The resulting video-graphic image has mattes of empty space above and below it; these mattes are part of each frame of the video signal.

<span class="mw-page-title-main">Pan and scan</span> Method for adapting widescreen film to television

Pan and scan is a method of adjusting widescreen film images so that they can be shown in fullscreen proportions of a standard-definition 4:3 aspect ratio television screen, often cropping off the sides of the original widescreen image to focus on the composition's most important aspects.

<span class="mw-page-title-main">Widescreen</span> Aspect ratio of a displayed image

Widescreen images are displayed within a set of aspect ratios used in film, television and computer screens. In film, a widescreen film is any film image with a width-to-height aspect ratio greater than 4:3 (1.33:1).

<span class="mw-page-title-main">35 mm movie film</span> Standard theatrical motion picture film gauge

35 mm film is a film gauge used in filmmaking, and the film standard. In motion pictures that record on film, 35 mm is the most commonly used gauge. The name of the gauge is not a direct measurement, and refers to the nominal width of the 35 mm format photographic film, which consists of strips 1.377 ± 0.001 inches (34.976 ± 0.025 mm) wide. The standard image exposure length on 35 mm for movies is four perforations per frame along both edges, which results in 16 frames per foot of film.

<span class="mw-page-title-main">Advanced Photo System</span> Still image film format

Advanced Photo System (APS) is a discontinued film format for still photography first produced in 1996. It was marketed by Eastman Kodak under the brand name Advantix, by FujiFilm under the name Nexia, by Agfa under the name Futura and by Konica as Centuria.

Anamorphic widescreen is a process by which a comparatively wide widescreen image is horizontally compressed to fit into a storage medium with a narrower aspect ratio, reducing the horizontal resolution of the image while keeping its full original vertical resolution. Compatible play-back equipment can then expand the horizontal dimension to show the original widescreen image. This is typically used to allow one to store widescreen images on a medium that was originally intended for a narrower ratio, while using as much of the frame – and therefore recording as much detail – as possible.

Negative pulldown is the manner in which an image is exposed on a film stock, described by the number of film perforations spanned by an individual frame. It can also describe whether the image captured on the negative is oriented horizontally or vertically. Changing the number of exposed perforations allows a cinematographer to change both the aspect ratio of the image and the size of the area on the film stock that the image occupies.

<span class="mw-page-title-main">14:9 aspect ratio</span> Television image format

14:9 is a compromise aspect ratio between 4:3 and 16:9. It is used to create an acceptable picture on both 4:3 and 16:9 TV, conceived following audience tests conducted by the BBC. It has been used by most UK, Irish, French, Spanish, Colombian and Australian terrestrial analogue networks, and in the US on Warner Bros. Discovery' HD simulcast channels with programming and advertising originally compiled in 4:3. Note that 14:9 is not a shooting format; 14:9 material is almost always derived from either a 16:9 or 4:3 shot, and no televisions have ever been made in 14:9.

<span class="mw-page-title-main">Open matte</span> Filming technique

Open matte is a filming technique that involves matting out the top and bottom of the film frame in the movie projector for the widescreen theatrical release and then scanning the film without a matte for a full screen home video release. It is roughly equivalent to an uncropped version of the film.

<span class="mw-page-title-main">Matte (filmmaking)</span> Photographic layering of multiple images

Mattes are used in photography and special effects filmmaking to combine two or more image elements into a single, final image. Usually, mattes are used to combine a foreground image with a background image. In this case, the matte is the background painting. In film and stage, mattes can be physically huge sections of painted canvas, portraying large scenic expanses of landscapes.

<span class="mw-page-title-main">Univisium</span> Universal film format

Univisium is a proposed universal film format created by cinematographer Vittorio Storaro, ASC, AIC and his son, Fabrizio, to unify all future theatrical and television films into one respective aspect ratio of 2:1.

<span class="mw-page-title-main">Pillarbox</span> Black bars on the sides of an image

The pillarbox effect occurs in widescreen video displays when black bars are placed on the sides of the image. It becomes necessary when film or video that was not originally designed for widescreen is shown on a widescreen display, or a narrower widescreen image is displayed within a wider aspect ratio, such as a 16:9 image in a 2.39:1 frame. The original material is shrunk and placed in the middle of the widescreen frame.

In television technology, Active Format Description (AFD) is a standard set of codes that can be sent in the MPEG video stream or in the baseband SDI video signal that carries information about their aspect ratio and other active picture characteristics. It has been used by television broadcasters to enable both 4:3 and 16:9 television sets to optimally present pictures transmitted in either format. It has also been used by broadcasters to dynamically control how down-conversion equipment formats widescreen 16:9 pictures for 4:3 displays.

Widescreen televisions provide several modes for displaying video from 4:3 sources. These modes may be selected manually from a remote control, or automatically if an Active Format Description is available.

<span class="mw-page-title-main">Windowbox (filmmaking)</span> The often undesirable combination of letterboxing and pillarboxing

Windowboxing in the display of film or video occurs when the aspect ratio of the media is such that the letterbox effect and pillarbox effect occur simultaneously. Sometimes, by accident or design, a standard ratio image is presented in the central portion of a letterbox picture, resulting in a black border all around. It is generally disliked because it wastes much screen space and reduces the resolution of the original image. It can occur when a 16:9 film is set to 4:3 (letterbox), but then shown on a 16:9 TV or other output device. It can also occur in the opposite direction and a few films have been released with this aspect ratio — one example is The Crocodile Hunter: Collision Course, which had numerous scenes with Steve & Terri Irwin using widescreen pillar boxing.

<span class="mw-page-title-main">Anamorphic format</span> Technique for recording widescreen images onto a 4:3 frame

Anamorphic format is the cinematography technique of shooting a widescreen picture on standard 35 mm film or other visual recording media with a non-widescreen native aspect ratio. It also refers to the projection format in which a distorted image is "stretched" by an anamorphic projection lens to recreate the original aspect ratio on the viewing screen. The word anamorphic and its derivatives stem from the Greek anamorphoo, compound of morphé with the prefix aná.

<span class="mw-page-title-main">Technology of television</span> Telecommunications, sound and video

The technology of television has evolved since its early days using a mechanical system invented by Paul Gottlieb Nipkow in 1884. Every television system works on the scanning principle first implemented in the rotating disk scanner of Nipkow. This turns a two-dimensional image into a time series of signals that represent the brightness and color of each resolvable element of the picture. By repeating a two-dimensional image quickly enough, the impression of motion can be transmitted as well. For the receiving apparatus to reconstruct the image, synchronization information is included in the signal to allow proper placement of each line within the image and to identify when a complete image has been transmitted and a new image is to follow.

"21:9" is a consumer electronics (CE) marketing term to describe the ultrawide aspect ratio of 64:27, designed to show films recorded in CinemaScope and equivalent modern anamorphic formats. The main benefit of this screen aspect ratio is a constant display height when displaying other content with a lesser aspect ratio.

Shoot and protect is a technique used in video and film production, in which the material is shot in such a way that the areas of interest within a frame lie within a rectangular "protected area" within the frame, with margins at top and bottom and both sides. The action safe and caption safe areas then lie within this protected area. This allows the resulting material to be cropped to any of a wide range of aspect ratios, whether wider or narrower than the shooting format, without losing the most important features of each shot or having to resort to pan and scan or letterboxing. A 14:9 safe area is often chosen as a compromise between 4:3 and 16:9 frame formats.

The aspect ratio of an image is the ratio of its width to its height. It is expressed as two numbers separated by a colon, width:height. Common aspect ratios are 1.85:1 and 2.40:1 in cinematography, 4:3 and 16:9 in television, and 3:2 in still photography.

References

  1. "Aspect Ratios – Filmbug".