This is the reason why this format is very popular on the Internet, in digital cameras, and desktop publishing. However, a notable drawback of JPEG is that it is a lossy compression. This format compresses digital images by dropping unneeded color data that are undetectable by the human eye. Furthermore, editing and resaving a JPEG image leads further to quality degradation.
File size: One of the notable advantages of JPEG over the PNG format is that it can achieve a smaller file size for a relatively similar image quality and resolution. This is ideal for storage and online content consumption. Another remarkable advantage of JPEG is that its degree or level of compression is adjustable. This adjustability enables a user to control or balance the tradeoff between image quality and file size. Usage: JPEG is ideal for images with smooth variations of colors.
However, unlike PNG and GIF, it is not ideal for images with texts or objects with sharp lines and edges between colors. This file format creates artifacts that are noticeable within the sharp edges between two or more different colors.
Because of the smaller file size of JPEG as compared to PNG, it is ideal for use in the web, as well as for storing professional print-quality graphics taken using a digital camera or produced using a graphic design software.
However, unlike GIF, it does not support animation. This means that image data and details are retained after compression. It also supports bit RGB color images.
Another advantage of PNG is that it supports grayscale images and transparency. It only takes a minute to sign up. Connect and share knowledge within a single location that is structured and easy to search.
Should there be a quality difference between these two? BMP is both uncompressed and lossless. PNG is compressed but lossless. Thus, with a lossless format the only visible difference is the file size. No difference in quality, both standards are lossless. BMP uncompressed takes more space, but when compressed e. However simple picture, such as a drawing you did in paint, or a diagram, will compress much better with. I again, tested this.
I did a logo in paint similar to a ford logo and compressed it with 7zip. Uncompressed, the png was kb, the bmp 1. Sign up to join this community. The best answers are voted up and rise to the top. Stack Overflow for Teams — Collaborate and share knowledge with a private group. Create a free Team What is Teams? Learn more. Ask Question. Asked 9 years, 9 months ago.
As smitty pointed out, file size is the key difference. Stevo14 PNG is compressed so the overall size of you game or app will be smaller when you go to distribute it. PNG also has an alpha channel which allows for gradient transparency as opposed to binary transparency. Ravyne The two main reasons, as have been said, are transparancy and compression.
PNG is nice because it can have transparancy built-in, while adding transparancy to a bitmap is really a bit of a hack, and not supported by many editors. PNG compresses nicely because it has several compression methods at its disposal Some work better for flat-shaded images cartoons, limited color images while others work better for more realistic scenes textures, photos ; PNG chooses the best one.
The net result is that simple images often compress better than GIFs, while more complex images offer compression very close to JPEG, with similar visual quality. The main benefit that BMP offers over PNG and most other formats is that it is incredibly simple to load, since its essentially a memory-image of the graphic data plus a small header. PNG and other compressed formats require a loader to de-compress the image as its loaded, making the loader more difficult to write.
That said, there are very mature, free loaders for nearly every image format, including PNG. In many ways, TGA is a middle-ground as it supports transparancy, is easier to load than PNG, but doesn't compress as well. Harry Hunt Bitmaps really are the most straightforward way of storing images. However, an uncompressed image can become pretty big. So a bitmap that is x at 32 bits per pixel will be 3 megs in size. PNGs are just like bitmaps in that they store pixel images , but a lossless compression is applied before saving the images.
This results in relatively small files. What's nice about PNGs is that the compression algorithm used is not covered by any patents which means you're free to use PNGs in your programs even if you plan on selling them. Unfortunately, uncompressing PNGs isn't easy. So while you could write the code to load a bitmap in about five minutes, with PNGs you will usually resort to using some sort of library. Also loading PNG:s takes much longer, so if have loads of images and your application needs to be loaded as quickly as possible, you might want to consider another format.
Also remember that while PNG files are much smaller that BMP:s when they are stored in your hard drive, they take the same amount of memory as BMP:s when uncompressed and loaded in to your application. Quote: Original post by teebee Also loading PNG:s takes much longer, so if have loads of images and your application needs to be loaded as quickly as possible, you might want to consider another format.
I suspect that's not entirely cut-and-dried.
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