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Lossy Formats
We are basically talking about jpg here. It is also possible for TIFF to be "lossy", if you use the compression algorithms when you save to TIFF.


Lossy compression
Techniques Glossary Lossy compression
Where pixels are removed (lost) to make the file size of a digital image smaller. When compressing images using the JPEG format you have the option of varying the level of compression.

Lossy audio formats
Lossy audio formats offer drastically reduced file sizes at the cost of compromised audio quality.

Lossy Compression
Lossy compression reduces the image size by discarding information and is similar to summarizing a document.

Lossy
Lossy (file format) refers to a characteristic of the file compression.

~
denotes a loss of data during Image file compression. Only occurs when higher compression rates are used.
Lossless ...

~ or ~ compression - A form of image compression when saving an image that discards (loses) data from it. Saving a picture as a .jpg or .jpeg is a method of ~ compression.
LOW KEY - Describes a mostly dark image, with few highlights.

~ - A form of image compression when saving the image that discards data from it. Saving a picture as a JPEG uses ~ compression.
LOUPE - A small magnifying glass used in viewing transparencies (slides), negatives and contact sheets. Generally a loupe's magnification is eight times.

~/Lossless files
When a digital camera takes a photo, the image data is stored on a memory card as a computer file. If the data is stored fully, the file is called a lossless file. These files are quite large in size. The most common type of lossless file in use are TIFFs.

~
Many file formats use compression to reduce the file size of bitmap images (digital photo). Lossless techniques compress the file without removing image detail or colour information; ~ techniques remove detail.

~. See Compression, ~.
LZW. A compression scheme used to reduce the size of image files.
Macro mode. A lens mode that allows you to get very close to objects so they appear greatly enlarged in the picture.

~ compression
A method of reducing image file size by throwing away unneeded data, causing a slight degradation of image quality. JPEG is a ~ compression method.
LPI (Lines per Inch)
The frequency of horizontal and vertical lines in a halftone screen.

~:
A form of compression that discards and compromises on the quality of data stored.
The JPEG file format is an example of ~ compression.

~
An image format that sacrifices a certain amount of image information in order to create a smaller compressed file.
LZW ...

~ encoding
A data compression or encoding algorithm that loses, or purposely throws away, input data during the encoding process to gain a better compression ratio. JPEG is an example of a ~ encoding method.
LPI ...

~ Compression
Software algorithms (and accompanying file formats) used for reducing files sizes were data (often targeting redundant data) is discarded during compression and is not fully restored when decompressed.

~ compression
A compression algorithm that reduces file size by actually removing imformation from the image, audio or video signal.

~: In order to achieve very significant quantities of file size reduction, information contained within the original file is discarded, resulting in a degradation of the image quality. This cannot be fully recovered (reconstructed) later.

~ compression. An image-compression scheme, such as JPEG, that creates smaller files by discarding image information, which can affect image quality. See also compression.
Luminance. The brightness or intensity of an image, determined by the amount of gray in a hue.

~ compression
A method of image compression where some image quality is sacrificed in exchange for higher compression ratios. The amount of quality degradation depends on the compression algorithm used and a user selected quality variable.

~
A data compression technique that can reduce the detail of a digital image file. Most video compression techniques utilize ~ compression.
Low-Pass Filter ...

~ compression - used by a file format such as JPEG - can create smaller files but in doing so throws away some of the original image data. The more compressed an image is with a ~ method the more degraded it becomes.

~
The RAW file format uses a lossless compression, and so it does not suffer from the compression artifacts visible with "~" JPEG compression. RAW files contain more information and achieve better compression than TIFF, but without the compression artifacts of JPEG.

~: Data compression techniques that reduce some detail of a digital image are described as being "~." Most digital photo and video compression techniques utilize ~ compression.

David De ~/Photodisc/Thinkstock
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JPGs are ~ compression. They throw away data very cleverly so it's not visible. They can save a lot more space than lossless compression. JPGs easily can throw away 90% of the file size and still look perfect! ...

I hate ~ compression. Keep your image quality settings high to avoid shots like that one. You might see this and think - Well, DUH! ...

~ compression. Because lossless compression isn't practical in many cases, all popular digital cameras offer a ~ compression (rhymes with "bossy"). This process degrades images to some degree and the more they're compressed, the more degraded they become.

'Lossless' techniques compress image data without removing detail; '~' techniques compress images by removing detail. Compression, lossless A file compression scheme that makes a file smaller without degrading the image.

JPEG images are typically saved using a ~ compression format (though a lossless JPEG compression is now available). Raw formats typically use lossless compression or high quality ~ compression.
Finer control.

There is a gnawing fear that somehow because JPEG is a "~" compression algorithm you'll be throwing away that vital pixel.

It produces high quality video at small file sizes and uses ~ intraframe compression.
AVI (Audio Video Interleave) developed by Microsoft, is a popular format for audio/video data on the computer but it is of relatively low quality.

These files are compressed, but in a non-~ manner. They are significantly smaller than equivalent TIFF files, but larger than JPEGs. Typically they achieve a compression of around 6:1 using 16-bit data, so files are 1/6 the size of equivalent TIFF files.

There are two general types of data compression: lossless and ~. Lossless compression has the advantage that no data is lost. So, lossless compression does not degrade the quality of images. The downside of lossless is that it can not be compressed as much as ~.

The most important thing to keep in mind is that JPEG is a ~ compression algorithm, meaning that every time you save a JPEG, you are losing information in the process of compressing it. Open a JPEG again, tweak something, then resave it and it gets even worse. Do it a third time, worse still.

However JPEG uses a ~ compression technique. A ~ compression technique reduces file size by discarding unneeded data, resulting in a slight degradation of image quality each time the file is saved and reopened. Just opening a JPEG file do not degrade the image; only when you re-save it.

A digital process that reduces the number of bits in an image to reduce the file size The benefit is that it takes less storage space and can be e-mailed quicker There are two types of compression - ~ which permanently loses detail and Lossless that returns all the data JPEG ~ compression is ...

The JPEG process is a '~' one, meaning that some data is removed, and color gradients are simplified, which may result in some image degradation based on the amount of compression you choose.

In computing, JPEG is a commonly used method of ~ compression for digital photography (image).It is the most common image file type captured by digital cameras, from standard point-and-shoot to DSLRs, and it provides easy compatibility with desktop software and Internet upload sites.

You can record them as uncompressed data or with ~ or lossless compression. You can choose between 12 bit and 14 bit tonal depth, although the latter significantly reduces the continuous shooting rate from 7 to 2.5fps (note, Canon's EOS 7D shoots 14-bit RAW files at its full 8fps speed).

However, because JPEG is a ~ compression scheme, images can be visibly degraded by the compression process. What's more, while most cameras capture 10 to 12 bits of color per pixel, JPEG files can hold only 8 bits of data per pixel.

This includes various NR (DFS and dark current), ~ compression (in the case of the compressed NEF format), loss-less compression (Canon TIF/CRW/CR2 formats), WB adjustments (in the original D1
and early D1x models) and (in the case of the 10D/300D) even sharpening applied in the RAW format.

PSD is the format Photoshop Elements and Photoshop CS uses for non-~ storage. That is, no matter how many times you open, edit and save your image, it won't lose any quality.
David.
Reply ...

JPEG is great for general photographic use. Used by all digital cameras, JPEG is a ~ format, which means it sacrifices some quality to ensure minimal small file size.
The advantages of using JPEG: ...

JPEG
Acronym for Joint Photographic Experts Group, and pronounced jay-peg. JPEG is a ~ compression technique for color images. Although it can reduce files sizes to about 5% of their normal size, some detail is lost in the compression.
K ...

JPG. This is the most common type of compressed image file format used in modern digicams. It is a "~" type of image storage because even in its highest quality mode, there is compression used to minimize its size.
Top
KB. A Kilobyte of data, or an abbreviation for keyboard.

It compresses the image in a ~ fashion, which means it discards picture information that people are unlikely to notice. That's great for minimizing storage requirements, but the drawback is that a serious photographer isn't going to be very keen on losing picture quality even to save space.

Joint Photographic Experts Group. A common method of image compression. JPEG compression is said to be '~', detail is permanently lost each time the image is edited and saved.
Mb
Megabytes.

JPG - The most common type of compressed image file format used in digicams. It is a "~" type of storage because even in its highest quality mode there is compression used to minimize its size.

In general, JPEG transformations are not reversible. Opening and then saving a JPEG file causes a new, ~ compression. Increasing the quality factor later will not bring back the image information which was lost.
L*a*b ...

It is referred to as a ~ format, which means some quality is lost in achieving JPEG's high compression rates. Usually, if a high-quality, low-compression JPEG setting is chosen on a digital camera, the loss of quality is not detectable to the eye.

An acronym fot the Joint Photographic Experts Group and is a standard for compressing image data. A JPEG is not a true file format, but is a compression method used within a file format. Sometimes referred to as a '~' format because some image quality is lost in order to achieve compression.

For example, prior to taking a picture, they can tell the camera how much contrast or saturation to apply to each image using the camera settings. As for post-processing, JPEG files are referred to as "~".

By eliminating very subtle color distinctions that the human eye usually cannot detect, JPEG images are compressed so that they can save faster and use less space. Because JPEG format actually alters an image, it's compression is said to be "~, ...

When discrepancies occur between the original and the reconstructed image, the compression is called ~. Lossless compressions can be achieved with compression ratios of up to 5 to 1. Files that are compressed may be identified by the file extension ".JPG.

" } , { "Title" : "Fixed Bit Rate" ,"GlossaryIcon" : "" ,"HideInGlossary" : "" ,"Summary" : "A type of ~ media compression that uses the same data per second throughout the entire audio/video file. The file size will be smaller than one with a variable bit rate.

See also: See also: What is the meaning of Image, Digital, Camera, Photograph, Compression?

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