PNG to JPG converter

.png

Microsoft Paint

PNG – is a scan-line graphic format developed as an alternative to GIF, a commercial license. However, they are both raster image types. PNG is based on the best features of the predecessor, including lossless compression and transparent background support. The PNG technology ensures the preservation of all stages of editing and the restoration of the step by preserving the quality. However, it does not allow us to save several pictures in one file at once, limiting its use in the development of animated images.

The PNG extension was proposed as a tool that helps to transfer and store images on the World Wide Web. The technology is limited to an 8-bit transparency channel so that you can adjust the colors from opaque to transparent. It supports 24-bit RGB colors, matching images, and shades of gray. However, as a non-professional format, PNG can not display other color spaces. Most programs allow you to open such files. They can also run in any browser. Images are different in small weight with good quality.

PNG Development Group (donated to W3C)

.jpg

JPG – is a popular graphic format characterized by a high image compression rate, which leads to a decrease in image quality. It uses the technology of encoding smooth color renditions, providing the ability to frequently reduce the amount of data during the image's recording. Because of the small size, it is requested by the owners of websites, allowing you to save the traffic effectively. It is also frequently used in memory cards of digital video cameras. The JPG algorithm is optimally suitable for compressing photographs and pictures in which realistic scenes with little contrast of colors are present. It is not recommended to use this format for compression of drawings and various kinds of graphics. A strong contrast between several near located pixels provokes the appearance of visible artifacts.

The procedure for compressing the digital images in JPG format is carried out in several stages. First, the photo is transformed into a color space YCbCr, and then it is divided into squares to determine the upper range of the color spectrum. Finally, the colors and brightness are coded. JPEG uses a "lossy" compression system and discrete cosine transform technology. The format acts simultaneously as the standard of ISO and the International Telecommunication Union. The file compression ratio is in the range from 10:1 to 100:1. In this case, the reduction in image quality can vary from insignificant to substantial.

The JPEG Committee