ตัวแปลงไฟล์ออนไลน์ฟรี 3GP เป็น CVSD

3GP is a multimedia container developed by Third Generation Partnership Project in 1998 for GSM-based (Global System for Mobile Communications) phones. The container requires little bandwidth, storage space and data usage that is why it is ideal for cell phones. It is a standard container for the files sent using MMS (Multimedia Messaging Service).

Continuously Variable Slope Delta modulation is a voice coding method. It is a delta modulation with variable step size (adaptive delta modulation), first proposed by Greefkes and Riemens in 1970