Compression of 3-D echocardiographic images using a modified 3-D set-partitioning-in-hierarchical-trees algorithm based on a 3-D wavelet packet transform

An efficient compression strategy is indispensable for 3-D digital echocardiography, which can provide more accurate diagnostic information than 2-D echocardiography without geometric assumption, but unfortunately requires a huge storage space. We describe a new set partitioning in hierarchical trees (SPIHT) algorithm that is based on the wavelet packet transform and use it to compress 3-D echocardiographic images. The new algorithm originates from the well-known SPIHT algorithm that is based on a wavelet transform but outperforms it for the compression of 3-D echocardiographic images. Experimental results are presented to verify the effectiveness of the new SPIHT algorithm. Results show that the new algorithm achieves a very high compression ratio while retaining good quality 3-D echocardiographic images.