You can use Pr software to reduce the compressed video size and keep the image quality unchanged. The specific operation is as follows:

Firstly, import the video file to be compressed in pr, drag it to the time panel, and click the file at the top of pr work interface;

2. Select Export and Media from the pop-up drop-down menu;

3. In the page that opens, click the format under Export Settings;

Fourth, choose H.264；;

5. Select the video below;

6. Under the bit rate setting column, click the menu box on the right side of bit rate coding;

7. Select CBR in the pop-up menu;

8. Change the target bit rate to 4;

9. We can see that the exported video file size is about 15MB, and then save it;

Ten, as shown in the figure below, the size comparison before and after video compression.