Hybrid Pixel-Based Method for Cardiac Ultrasound Fusion Based on Integration of PCA and DWT

Table 1

Advantages and disadvantages of the various image fusion methods.

Method	Domain	Advantages	Disadvantages
PCA (principal component analysis)	Spatial	(i) Fused images have high spatial quality; (ii) Extract main features to minimize redundancy; (iii) Preserve more spectral information contents; (iv) Keep a better resolution	(i) Artifacts of spectral feature images and the reference low resolution images with different degrees; (ii) Spectral degradation; (iii) Not suitable for medical images
DWT (discrete wavelet transform)	Transform	(i) Have least spectral distortion; (ii) Preserve more spatial features; (iii) Produce directional info in decomposition level and include salient information at various resolution; (iv) Give a good signal to noise ratio compare to pixel based approaches	(i) Less spatial resolution for final fused image; (ii) Not suitable for medical images
Proposed method (integration of PCA and DWT)	Transform	(i) Integrate PCA and DWT advantages and powerfully improve fused image quality to avoid distortions; (ii) Preserve more spatial features and more spectral information contents; (iii) Extract main features to minimize redundancy; (iv) Output image will contain high spatial resolution and also high quality spectral content	—