PNG and JPG, jif format for pictures

One: GIF (Graphics interchange Format)

Brief introduction

The GIF Graphics Interchange format is a bitmap graphics file format that reproduces true-color images in 8-bit colors (that is, 256 colors).

It is actually a kind of compressed document, using LZW compression algorithm to encode, effectively reduce the image file on the network transmission time.

It is one of the most widely used image formats for network transmission at present.

Advantages

1. Excellent compression algorithm to a certain extent to ensure that the image quality, while the volume becomes very small.
2. Multiple frames can be inserted for animation effects.
3. You can set the transparent color to produce the effect that the object emerges above the background.

Disadvantages

Due to the use of 8-bit compression, up to 256 colors can be processed, it should not be applied to the true color image.
Two: PNG (portable Network Graphics)

Portable Network Picture (portable networks graphics), or PNG, is a lossless data compression bitmap graphics file format.

PNG format is lossless data compression, allowing the use of a color palette technology similar to GIF format, supporting true color images and having alpha (translucent) features.

There are many people using PNG format on the Internet and other aspects now.

PNG specification (with knowledge of more detailed theories, and adventurous children's shoes can go to see sorry is in English)

Advantages

* Support 256 color palette technology to produce small volume files
* Up to 48-bit true color images and 16-bit grayscale images are supported.
* Supports the translucent nature of the alpha channel.
* Gamma correction information for image brightness is supported.
* Support for storing additional text information to preserve image name, author, copyright, authoring time, comments, etc.
* Use lossless compression.
* Asymptotic display and streaming read and write, suitable for quick display of preview effect in network transmission and then display the whole picture.
* Prevent file errors with CRC cyclic redundancy coding.
* The latest PNG standard allows multiple images to be stored within a single file.

Disadvantages

But there are also some software that cannot use the appropriate predictions to create overly bloated PNG files.

Three: JPG (Joint Photographic Experts Group)

JPEG is a standard method of distortion compression, which is widely used for photo images.

JPEG compression is usually a destructive data compression (lossy compression), meaning that the quality of the image will suffer visible damage during the compression process.

Advantages

JPEG/JFIF is the most common format used to store and transfer photos on the World Wide Web (Wide).

JPEG can achieve its best results in tonal and color-changing photographs or realistic painting (painting).

In this case, it is usually better than a completely undistorted method and can still produce very good-looking images (in fact it would be more common than other

Methods like GIF produce higher-quality images, because GIF has no distortion for line painting (drawing) and graphic diagrams,

For full-color images, however, very difficult quantification is required.

Disadvantages

It is not suitable for line drawing (drawing) and other text or diagram (iconic) graphics, because its compression method is used in the shape of these shapes,

will get inappropriate results.

Four: The simplest way to differentiate is:

PNG can be ported to the network Graphics format, is also a bitmap file storage format for lossless compression.

And JPG is our most common image format, images occupy less storage, but also sacrificed the image quality.

Simply to say is a lossless, a lossy.

JPG is a lossy image compression type, lossy compression method to remove redundant images and color data,

Get very high compression rate while showing a very rich and vivid image, in other words, you can use the least disk space to get better image quality.
PNG is not compressibility, can save a transparent graph, it also provides 24-bit and 48-bit true color image support and many other technical support.

The PNG format is editable. The tablet has fonts, etc., can be changed with PS
JPG format is not editable.
For resolution of both formats, PNG is higher than JPG.
PNG is not suitable for any occasion, because it is bulky and does not utilize the display, and is used entirely by the editor as a backup for subsequent changes to the image.
JPG format is used for many occasions, not one by one cases.

PNG and JPG, jif format for pictures