Memory management method and system

The invention discloses a memory management method and system, and the method comprises the steps: setting a memory unit with a corresponding size according to the related parameters of each coding channel, and the memory unit being separated from a system memory; dividing the memory unit into an I-frame memory pool for storing I-frame data and a non-I-frame memory pool for storing non-I-frame data; and respectively performing memory allocation and release management on the I-frame memory pool and the non-I-frame memory pool. According to the method, a memory unit is separated from a system memory, so that a large number of memory fragments generated by frequent allocation and release of the system memory can be avoided. The memory unit is divided into an I-frame memory pool and a non-I-frame memory pool, P-frame data which are distributed and released frequently and are small in data size are isolated from I-frame data which are distributed relatively infrequently and are large in data size, and the situatio