Network camera-image compression method

JPEG (English name: Joint Photographic Experts Group) compression technology can be said to be the basis of all image compression technologies. It is suitable for the compression of static images, directly processing the entire picture, the compression ratio is 20-80 times, and there is no room for resolution. Therefore, it is necessary to wait for the entire compressed file to be transferred before decompression into an image screen, and this method causes the transmission of a high-resolution screen to take tens of seconds or even minutes.

MJPEG (Motion JPEG) is a dynamic image compression technology developed on the basis of JPEG. It only compresses a certain frame independently, and basically does not consider the changes between different frames in the video stream. It makes it possible to obtain high-definition video images, and can flexibly set the video resolution and compression frame number of each channel. The compressed picture can also be edited at will. However, its shortcomings are also very obvious. First, it has serious frame loss and poor real-time performance. It is difficult to complete real-time compression on the premise that every channel must be high-definition. Second: low compression efficiency and large storage space.

Later, there was a multi-layer JPEG (ML-JPEG) compression technology, which adopted a gradual layer technology, first transmitted low-resolution image files, and then supplemented with more detailed compressed data to improve picture quality. Although the time required for this method is the same as the original method. But since the screen can be seen first, users will find this method better.