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What are the advantages and disadvantages of lossless and lossy compression?
Wiki User
∙ 13y ago
Lossless compression results in a closer representation of the original media, and thus a higher quality end product. The disadvantage is that the resulting file will be larger than if you had used a lossy compression format.
Lossy compression can give you a smaller file size, but the resulting end product may be in some ways inferior to the original.
Wiki User
∙ 13y ago
Wiki User
∙ 15y agoThese terms are usually associated with compression.
A lossy compression scheme is one where a file is compressed by removing some of the information contained in the file to make it smaller. For instance, JPEG picture compression removes some picture information resulting in a lower quality image, but much smaller file size.
A lossless compression scheme is one where the original file before and after remains completely unchanged. To keep with the example, TIFF would be the corresponding lossless compression scheme to JPEG.
see http://en.wikipedia.org/wiki/Lossy_compression
Wiki User
∙ 8y agoLossy compression occurs when a file is compressed, such as audio, movie or picture, and data is lost; due to limitations in the senses of humans these losses are not noticeable (unless something is repeatedly compressed and uncompressed when the losses add up and a drop in quality is noticed). For example, BRRRRBBBBG can be compressed to RB. That means that the first B and G is gone and it can not be restored. Examples of lossy compression are MPEG (for movies) and JPEG (for pictures).
Non-lossy compression compresses a file and doesn't lose data. For example can we say that BBBBBRRRRGGGG can be B5 R4 G4. When you open the file again the system reads and understands how it should be and restores it to exactly the way it was before. This kind of compression is good for text documents or pictures with large areas of a single colour; it is imperative for backups.
Wiki User
∙ 14y agoLossy compression of media (pictures, video, or music) implies some loss of quality occurs during the compression.
In many cases, this loss of quality may be imperceptible, yet result in significant size savings. However, much like each generational copy of a videotape looks worse than it's predecessor (the "copy of a copy of a copy..." problem), each time you re-compress or change the format of a file in a lossy compression format, it will look/sound worse.
"Lossless" (not "lossyless") compression entails no loss of quality, and is therefore completely reversable. You can compress and recompress something in a lossless way as many times as you'd like.
Lossless compression is far less effecient that lossy compression, and results in much larger files.
In modern practice, lossy compression is far more common. Examples of lossy compression formats include MP3, AAC and WMA audio files, JPEG compression files (including those taken by high end digital cameras), and all digital video you're likely to have ever encountered (including DVDs).
Examples of lossless compression formats include WAV audio, FLAC audio, TIFF and RAW pictures (also taken by some high end digital cameras).
Audiophiles and Photography professionals may find it's worth the extra storage space to keep losslessly compressed data around, though most laymen wouldn't be able to tell the difference.
Lossless video is almost exclusively used in scientific/industrial applications, digital theater projection systems, and major motion picture video editing with multi-million dollar budgets. The amount of data involved in keeping digital video around in a losslessly compressed way is entirely impractical for most applications.
Wiki User
∙ 15y agothere is no difference as such infact these two techniques are used together to obtain the highest compression ratios.
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How does compression effect images?
Any type of compression will ideally reduce the size of an image. There are two types of compression which describe how they affect images:"Lossy" compressionThis type of compression reduces the size of the image by removing some data from it. This generally cause, effect the quality of the image, which mean it will reduce your image quality."Lossless" compressionThis type of compression reduces the size of the image by changing the way in which the data is stored. Therefore this type of compression will make no changes in your image.
A sound format that takes up less space on a hard drive or other media than does raw digitized sound?
A variety of digital audio formats require less memory than "raw digitized sound," which is generally stored in .aif or .wav format. Compressed audio comes in two basic varieties: lossless and lossy. Lossless compressed audio formats are ones which store the data in such a way that the audio quality is not deminished. A lossless audio file will require more memory than a comparable lossy compressed file but less than a raw one. Popular examples include: flac, apple lossless Lossy compressed audio formats do deminish audio quality but reduce file greatly. Popular examples include: mp3, aac
What is the difference between MPEG JPEG and?
1. JPEG stands for joint photographic expert group and MPEG stands for motion picture expert group. 2. JPEG is used for picture compression and MPEG is used for video compression. 3. JPEG typically achieves 10:1 compression with little perceptible loss in image quality, whereas compression ratio in MPEG is 30:1 for general video using H.263 and 50:1 for general video using H.264/MPEG4. 4. JPEG and MPEG both uses lossy compression.
How is video represented in a computer?
Video is represented as a sequence of bitmap images often with a synchronized soundtrack. Because of the enormous size of video files they are almost always compressed using lossy techniques.
Why are BITMAP files larger than VECTOR files?
Bitmap files are bigger for two reasons, first BMP is an abbreviation of bitmap and every bit in the picture is mapped. Second Jpeg files are compressed using a lossy compression algorithm so some information is discarded. This is why you lose quality when you save a .bmp as a .jpg. In fact, every time you edit and save a Jpeg file, you lose more information, leading to a constant degradation in quality.--------------------------Update: Actually, while BMP is indeed an abbreviation for "bitmap", it is not true that every bit in a BMP file is mapped in all cases. BMP files come in a variety of "flavors", but in general they can be broken down into "compressed" and "uncompressed". In the uncompressed variant of BMP files, it is correct that each bit is indeed "mapped" and as such the files tend to be larger than many other common image file formats. However, most BMP files that are in circulation or created by applications such as MS Paint are compressed BMP files. BMP files use a type of compression called "run length encoding", or RLE. Run length encoding will basically identify strings of adjacent pixels that are the same color value, and use a shorthand to indicate how many of that color. For example, imagine that the symbol "*" represents a certain shade of blue, and all other punctuation marks represent various other colors. Imagine, too, that there is a long horizontal line of blue pixel (a line) within a picture, and surrounded by various other colors. The RLE version of that might look something like this:^2$1#1%1^2&1*240.1?1.1?.>1The pattern in this case (just a theoretical example of how RLE encoding works) is [PIXELCOLOR][REPETITON]. You will notice two things - there are two entries for every pixel reference (this can cause a RLE encoded BMP file to be LARGER than the original file -- if there are a whole bunch of 1-2 pixel areas and not many areas in the image that are solid colors; secondly, this "bloat" is significantly counteracted when the "*240" is encountered, since the original (uncompressed) would have looked like 240 asterisks one after the other.So, certain images compress better than others, and certain compression types are more suitable for certain image types. RLE is indeed one of the lossless types of compression. Lossless compression typically results in poorer compression ratios, but once decompressed, since none of the original image information has been discarded ("lost"), the decompressed version of the file will look exactly like the original.JPEG, which is an acronym for the Joint Photographic Experts Group which developed the algorithms behind this popular compression, works better on pictures than on images with large areas of identically colored pixels. JPEG is a lossy compression, meaning that each time the image is compressed with this format, certain bits of information are "approximated" to improve the compression ratio; thus, when the file is decompressed for viewing, there are changes to the image quality. JPEG compression can be adjusted to provide better image quality by sacrificing some of the compression, or can be adjusted to be more highly compressed but with a sacrifice of image quality. For most of the images on the in Internet, a balance is struck between good visual quality and good compression. However, since photographs are very common on the web, JPEG is perhaps the most popular format to be used online. JPEGs can provide a great compromise between acceptable image degradation and file size. However, since the compression algorithms have been specifically designed to work with the unique data that is seen insde a photograph, JPEG will usually wind up as a smaller file than BMP. However, if you convert an image that is only made from a small number of distinct colors, and those colors are mainly ground together in areas of the image, then a BMP file format might actually result in a smaller file.So, if you are trying to decide which format you want to use, you have to decide whether a certain degree of image degradation is acceptable or not, and you should test while retaining copies of the original files (just in case). Generally, for web pages and items that will be displayed from within a web browser, you want to stay away from BMP, because it is not supported by all web browsers (MSIE supports it, however). If you need the page background to show through the "negative space" of your image, and not be blocked out as the background color of the image, then you will do better abandoning JPEG and BMP entirely, and using either GIF or PNG and taking advantage of these file formats' (some variants') inherent support for transparency and/or an "alpha channel."
Are PNG files lossy or lossless?
Lossless. Compression techniques do not remove detail from the image.
Is GIF lossless or lossy?
GIF is a lossless compression introduced by CompuServe in 1987 using Lempel-Ziv-Welch (LZW) lossless data compression.
Is TIFF lossy or lossless?
lossless
Is a PICT a type of Lossy or Lossless compression file?
Pict files can use 2 different forms of compression. 1- RLE Compression (the default) is lossless. 2- JPEG compression (only on some systems/graphics programmes) is lossy.
Are EPS files lossy or lossless?
they are lossless...
Are AI files lossy or lossless?
Lossy
D- What is the difference between lossy and lossyless compression?
Lossless compression recreates a compressed file as an identical match to its original form. While lossy compression can't be used to compress anything that needs to be reproduced exactly.
Is huffman coding lossy or lossless?
lossless
Difference between lossless and lossy compression?
File compression uses software algorithms to reduce file size by reducing the bit-rate of a file. Lossy compression takes it a bit further and lowers the quality of thr file to make it even smaller. Lossy compression is commonly used for media files, but would not be appropriate for other types of files.
Is DOC lossy or lossless?
shush
What is it called when compression data some of the data is lost yet can represent the original close enough?
When compressed data that is subsequently decompressed does not exactly match the original, yet it is considered close enough to the original to be usable, that algorithm is called a lossy compression. Contrast that with lossless compression, where the decompressed version exactly matches the original. Lossy compression is useful in audio and video, where exactness is not critical, while lossless compression is useful in data streams that must be preserved exactly. The lossy compression algorithm often results in more compact compressed results.
Electromagnetic waves in lossless dielectric and lossy?
plane waves in lossy dielectrics
