通过DCT变换，大致掌握了量化压缩编码的基本原理、算法，并通过编程给予了实现，了解到压缩性能及其重建效果的影响、作用。-By DCT transform, generally mastered the basic principle, algorithm quantization coding and compression, and gives the realization by programming, to understand the influences, compression performance and reconstruction effect.