Thumbnails are reduced-size versions of pictures or videos, used to help in recognizing and organizing them, serving the same role for images as a normal text index does for words. In the age of digital images, visual search engines and image-organizing programs normally use thumbnails, as do most modern operating systems or desktop environments, such as Microsoft Windows, macOS, KDE (Linux) and GNOME (Linux). On web pages, they also avoid the need to download larger files unnecessarily.
Thumbnails are ideally implemented on web pages as separate, smaller copies of the original image, in part because one purpose of a thumbnail image on a web page is to reduce bandwidth and download time.
Some web designers produce thumbnails with HTML or client-side scripting that makes the user's browser shrink the picture, rather than use a smaller copy of the image. This results in no saved bandwidth, and the visual quality of browser resizing is usually less than ideal.
Displaying a significant part of the picture instead of the full frame can allow the use of a smaller thumbnail while maintaining recognizability. For example, when thumbnailing a full-body portrait of a person, it may be better to show the face slightly reduced than an indistinct figure. However, this may mislead the viewer about what the image contains, so is more suited to artistic presentations than searching or catalogue browsing.
Thumbnail makes for smaller, more easily viewable pages and also allows viewers to have control over exactly what they want to see.
In 2002, the court in the US case Kelly v. Arriba Soft Corporation ruled that it was fair use for Internet search engines to use thumbnail images to help web users find what they seek.
The word "thumbnail" is a reference to the human thumbnail and alludes to the small size of an image or picture, comparable to the size of the human thumbnail.While the earliest use of the word in this sense dates back to the 17th century, the American Heritage Dictionary of Idioms is reported to have documented that the expression first appears in the mid-19th century to refer to 'a drawing the size of the thumbnail'. The word was then used figuratively, in both noun and adjective form, to refer to anything small or concise, such as a biographical essay. The use of the word "thumbnail" in the specific context of computer images as 'a small graphical representation, as of a larger graphic, a page layout, etc.' appears to have been first used in the 1980s.
The term vignette is sometimes used to describe an image that is smaller than the original, larger than a thumbnail, but no more than 250 pixels in the long dimension.
Directors, storyboard artists and graphic designers, as well as other kinds of visual artists, use the term "thumbnail sketch" to describe a small drawing on paper (usually part of a group) used to explore multiple ideas quickly. Thumbnail sketches are similar to doodles, but may include as much detail as a small sketch. A "comprehensive" thumbnail sketch of a printed project, more or less to final size, is often referred to as a "comp", and can be highly detailed, with production information included. The purpose of thumbnails was to visualize the ideas in a miniature form, similar to an illustration shorthand. Often, the old school animators used this process to quickly jot down the key "poses" that were part of an animation sequence. These compact drawing were then pinned up above the animation table, within easy view. As the animator worked through creating the final drawings of each pose, the thumbnails helped to keep the original ideation relevant.
In digital imaging, a pixel, pel, or picture element is the smallest addressable element in a raster image, or the smallest addressable element in a dot matrix display device. In most digital display devices, pixels are the smallest element that can be manipulated through software.
Portable Network Graphics is a raster-graphics file format that supports lossless data compression. PNG was developed as an improved, non-patented replacement for Graphics Interchange Format (GIF)—unofficially, the initials PNG stood for the recursive acronym "PNG's not GIF".
In computer graphics and digital photography, a raster graphic represents a two-dimensional picture as a rectangular matrix or grid of square pixels, viewable via a computer display, paper, or other display medium. A raster is technically characterized by the width and height of the image in pixels and by the number of bits per pixel. Raster images are stored in image files with varying dissemination, production, generation, and acquisition formats.
Exchangeable image file format is a standard that specifies formats for images, sound, and ancillary tags used by digital cameras, scanners and other systems handling image and sound files recorded by digital cameras. The specification uses the following existing encoding formats with the addition of specific metadata tags: JPEG lossy coding for compressed image files, TIFF Rev. 6.0 for uncompressed image files, and RIFF WAV for audio files. It does not support JPEG 2000 or GIF encoded images.
Digitization is the process of converting information into a digital format. The result is the representation of an object, image, sound, document, or signal obtained by generating a series of numbers that describe a discrete set of points or samples. The result is called digital representation or, more specifically, a digital image, for the object, and digital form, for the signal. In modern practice, the digitized data is in the form of binary numbers, which facilitates processing by digital computers and other operations, but digitizing simply means "the conversion of analog source material into a numerical format"; the decimal or any other number system can be used instead.
A digital image is an image composed of picture elements, also known as pixels, each with finite, discrete quantities of numeric representation for its intensity or gray level that is an output from its two-dimensional functions fed as input by its spatial coordinates denoted with x, y on the x-axis and y-axis, respectively. Depending on whether the image resolution is fixed, it may be of vector or raster type.
A penciller is an artist who works on the creation of comic books, graphic novels, and similar visual art forms, with a focus on the initial pencil illustrations, usually in collaboration with other artists, who provide inks, colors and lettering in the book, under the supervision of an editor.
The display resolution or display modes of a digital television, computer monitor or display device is the number of distinct pixels in each dimension that can be displayed. It can be an ambiguous term especially as the displayed resolution is controlled by different factors in cathode ray tube (CRT) displays, flat-panel displays and projection displays using fixed picture-element (pixel) arrays.
Digital painting is an art medium created with computer technologies. It employs pixels which are assigned a color to create imagery. It is also known as raster graphics. It is called digital painting because it initially distinguished itself from vector graphics in its ability to render gradiated or blended colors in imagery which mimicked traditional drawing and painting media.
A spacer GIF is a small, transparent GIF image that is used in web design and HTML coding. They were used to control the visual layout of HTML elements on a web page, at a time when the HTML standard alone did not allow this. They became mostly obsolete after the browser wars-fueled addition of layout attributes to HTML 2.0 table tags, and were mostly unused by the time Cascading Style Sheets became widely adopted.
In computer graphics, image tracing, raster-to-vector conversion or raster vectorization is the conversion of raster graphics into vector graphics.
In computer graphics and digital imaging, imagescaling refers to the resizing of a digital image. In video technology, the magnification of digital material is known as upscaling or resolution enhancement.
On Microsoft Windows operating systems, starting with the Internet Explorer 4 Active Desktop Update for Windows 95 to 98, a thumbnail cache is used to store thumbnail images for Windows Explorer's thumbnail view. This speeds up the display of images as these smaller images do not need to be recalculated every time the user views the folder.
Thumbshots are screenshots of online documents such as web page in small thumbnail sizes. Thumbshots help users to visualize web sites or preview links before clicking. The dimension of a thumbshot image is generally much smaller than the actual online document allowing users to download and view a sample of the document quickly. Thumbshots can be automatically generated by custom software or manually screen captured using popular graphics programs.
Digital photography uses cameras containing arrays of electronic photodetectors interfaced to an analog-to-digital converter (ADC) to produce images focused by a lens, as opposed to an exposure on photographic film. The digitized image is stored as a computer file ready for further digital processing, viewing, electronic publishing, or digital printing. It is a form of digital imaging based on gathering visible light.
FlashPix is a bitmapped computer graphics file format where the image is saved in more than one resolution. Its design anticipated that when an HTTP request is sent for the file by a browser plugin implementing the format, only the image compatible with the current screen resolution is returned to the browser, saving on bandwidth and download time.
Scanography, more commonly referred to as scanner photography, is the process of capturing digitized images of objects for the purpose of creating printable art using a flatbed "photo" scanner with a CCD array capturing device. Fine art scanography differs from traditional document scanning by using atypical objects, often three-dimensional, as well as from photography, due to the nature of the scanner's operation.
FastPictureViewer is a freemium image viewer for Windows XP and later. Its aim is to facilitate quick review, rating and annotation of large quantities of digital images in the early steps of the digital workflow, with an emphasis on simplicity and speed. As an app with a freemium license, a basic version is available cost-free for personal, non-profit or educational uses, while a commercial license is required for the professional version with additional features. The basic version starts as a full version trial.
The International Dunhuang Project (IDP) is an international collaborative effort to conserve, catalogue and digitise manuscripts, printed texts, paintings, textiles and artefacts from the Mogao caves at the Western Chinese city of Dunhuang and various other archaeological sites at the eastern end of the Silk Road. The project was established by the British Library in 1994, and now includes twenty-two institutions in twelve countries. As of 18 February 2021 the online IDP database comprised 143,290 catalogue entries and 538,821 images. Most of the manuscripts in the IDP database are texts written in Chinese, but more than fifteen different scripts and languages are represented, including Brahmi, Kharosthi, Khotanese, Sanskrit, Tangut, Tibetan, Tocharian and Old Uyghur.
Image editing encompasses the processes of altering images, whether they are digital photographs, traditional photo-chemical photographs, or illustrations. Traditional analog image editing is known as photo retouching, using tools such as an airbrush to modify photographs or editing illustrations with any traditional art medium. Graphic software programs, which can be broadly grouped into vector graphics editors, raster graphics editors, and 3D modelers, are the primary tools with which a user may manipulate, enhance, and transform images. Many image editing programs are also used to render or create computer art from scratch. The term "image editing" usually refers only to the editing of 2D images, not 3D ones.
Thumbnail files are designed to display quickly and allow multiple images to be displayed simultaneously on a monitor screen for browsing. Thumbnails are 160 pixels on the long-dimension.