Some Common Myths and Facts about JPEG Format of Images
Images are the widespread and the most inexpensive media that enable us keeping memories of the special moments in our life and go through them again whenever we feel like. Today, smartphones are the most commonly own devices that include high definition cameras able to click remarkable images. In fact, you can see people around you carrying smartphones, clicking photos, and sharing them on social networks. The quality of the images clicked is subject to the quality of the camera and the format of the images. Well, JPEG is the most common image format that you can see as the extension of the images clicked with smartphones, digital cameras, DSLRs or similar device.
Have you ever wondered about what we call the format of the image? How could somebody have a mindset for something he does not have any idea about? Well, I am talking about the myths and facts people believe about the most common image format named JPEG. See what people have in their minds about the images of JPEG format below.
The JPEG Format
The term JPEG stands for Joint Photographic Experts Group and it refers to a standard method of image compression. Almost all the images use this particular file format, no matter whether you click one with your smartphone or a digital camera. In fact, JPEG (*.jpeg) is sometimes used as JPG (*.jpg); however, both of them are just same.
The Hidden Facts about JPEG File Format
JPEG file format – a form of digital compression of images – was developed to minimize the time a web page takes in loading. Well, the hidden truth in JPEG compression technique is, it eradicates the certain digital information in order to reduce the size of the images without affecting their visual quality too much, as there must be certain unit of degradation for displaying images on the web. In addition, mentioned below are some hidden facts about JPEG file format of the images:
The term JPEG also stands for a well-known standard, having a number of both free and paid software.
When it comes to images/photographs and paintings, JPEG turns out the best file format and offers the best quality realistic images having a smooth variation in both color and tone.
The downsampling ratios for JPEG file format are 4:4:0 (i.e. both vertical and horizontal directions can be decimated by a factor of 2), 4:2:2 (i.e. the vertical direction can be decimated by a factor of 2), and 4:4:4 (i.e. there will not downsampling).
There can be a slight variation in the resultant compression ratio based on the need, which also relies on the aggression level of divisors used in the phase called quantization.
Important: The Joint Photographic Experts Group (abb. as JPEG) is on the verge of unveiling their brand new JPEG 2000, the wavelet-based standard, which is targeted to replace the current JPEG standard.
The Myths about JPEG File Format
Users might have adequate information about JPEG file format since they every day click images of this file format, they do have certain myths as well in their minds about JPEG format of images. Some of such myths are discussed in the below section:
A belief, JPEG images lose their quality every time you open and close them.
It is a belief of many users that the JPEG images get their quality degraded every time when you open and close them. However, the belief has no underpinning. In other words, opening and closing the images of JPEG or even any other file format does not hard them in any manner. Even though you edit JPEG images, the images remain unaffected during the same session and do not lead to any quality degradation. Besides, copying or moving JPEGs from one location to another also have no effect on the quality of the images.
A belief, JPEG images lose their quality every time you use them in a page layout program.
Many users strongly believe that when JPEG images are used in some page layout or in sort of programs, it edits them and the images’ quality is affected adversely. I must say, the compression techniques used by different programs are different in nature, and therefore have different effects on the images used. In some cases, you may experience the documents’ layout larger than what was expected to be the total of all the JPEG images added.
A belief, multistage compression of JPEG images results in compressions done at the final state only.
Another belief says that compressing a JPEG image multiple times by certain percentages of its quality, results in the image compression done at the final stage only. For instance, suppose you compress an image by 30 percent and save it; later, you open it and compress it by 10 percent and save it. Then the final compression in the image will be only 10 percent. Well, the assumption is groundless, as the final compression will reduce the image quality by 30 % + 10 % and the final quality measure will be 63 %.
Quality = Quality’ + Quality”, where Quality’ = [Quality x (100 – 30)]/ 100; Quality” = [Quality’ x (100 – 10)]/100.
However, the compression process must be authenticated. Otherwise, the process may lead to JPEG corruption. Even though you can go for a step called JPEG Repair Tool in such cases, it is certainly a wise decision to use the tools that are authorized for such tasks, as assure that there will be no extra overhead.