Why did the video I recorded become smaller after conversion by the converter, but it was not seen for a long time?
Compression, it will compress the quality of video, just like compressing cookies, but this change is irreversible and it will reduce. Under normal circumstances, you will not go back after the conversion, which will affect the image quality. Then audio compression. If the pursuit is not very high, 4M is enough. He will delete some things that he thinks are unnecessary, but generally he will not reduce them. See if it was accidentally deleted or not put.