Why is it that whenever i save a image as a jpg. file the pixels spread, and what type of image should i save it as?
4
answers
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Answer it!
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Oct 10, 2009. 6:45 PMRe-design
says:
There are some compression losses with jpg to make the files smaller. But Jpg is a great way to save files. You should be able to choose low, medium or high quality when you save. I don't know what you're using to save them.
Also if the quality of the image coming from the camera is not good then your picture won't be any better.
Saving as a Tiff file retains the best quality. There are no compression losses with tiff. but the files are large.
Also if the quality of the image coming from the camera is not good then your picture won't be any better.
Saving as a Tiff file retains the best quality. There are no compression losses with tiff. but the files are large.
Oct 10, 2009. 7:56 PMplane phanatic
says:
I normally use the .PNG extension/file type when saving photos and some of my graphic designing. PNG is a newer format that uses ZIP compression (which is lossless) to save images. It also has 24 or 48 bits of RGB depending on the image.
Oct 10, 2009. 6:46 PMorksecurity
says:
I'm not sure what you mean by "the pixels spread"; there are several possible alternatives.
1) Are you saving the image at its full size? If you shrink it, unless you use an interpolating image resizer, you will lose detail.
2) JPEG uses "lossy compression". The more you tell it to compress the image, the more error will be introduced. The algorithm tries to minimize how badly this affects the percieved quality of the image, but throwing away data unavoidably means the image is going to be less sharp. Most programs that can write out JPEG can be told how much or how little to compress; you may want to let the file become larger in exchange for more accuracy.
3) If you're saving an image which has large areas of flat color -- a computer-generated bar chart, for example -- you may do better saving the image as a GIF file. GIF uses "run length encoding" compression, which doesn't work well on fully rendered image but is very effective when used on the kinds of images it was designed for -- and is lossless, so the image will be as good as the bitmap was.
There are other compressed image formats, but these two (plus straight bitmaps) are the most widely supported.
Of course something else may be going on, since you didn't provide any details of your problem.
1) Are you saving the image at its full size? If you shrink it, unless you use an interpolating image resizer, you will lose detail.
2) JPEG uses "lossy compression". The more you tell it to compress the image, the more error will be introduced. The algorithm tries to minimize how badly this affects the percieved quality of the image, but throwing away data unavoidably means the image is going to be less sharp. Most programs that can write out JPEG can be told how much or how little to compress; you may want to let the file become larger in exchange for more accuracy.
3) If you're saving an image which has large areas of flat color -- a computer-generated bar chart, for example -- you may do better saving the image as a GIF file. GIF uses "run length encoding" compression, which doesn't work well on fully rendered image but is very effective when used on the kinds of images it was designed for -- and is lossless, so the image will be as good as the bitmap was.
There are other compressed image formats, but these two (plus straight bitmaps) are the most widely supported.
Of course something else may be going on, since you didn't provide any details of your problem.
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