Digital micromirror device (DMD) allows very fast binary light modulation. For digital hologram displaying using DMD, binarization should be applied. In this work, 12 error diffusion and 8 dot diffusion binarization algorithms were considered. All methods were used in both iterative and non-iterative forms. Quality of reconstructed images from binarized holograms was compared. Optically registered digital holograms and synthesized holograms of binary and grayscale images were used. Among the error diffusion methods, Stucky’s and Atkinson's standard error diffusion methods and dot diffusion methods provide the highest quality of reconstruction. The effect of the pixel bypass matrix on the quality of reconstructed images was also evaluated. As bypass matrices, standard variants (for example, direct and reverse sequential bypass of pixels on rows or columns, a matrix with a line-by-line alternating direction of bypass of pixels, a spinning and swirling spiral matrices), and more complex types (for example, used in the Knuth dot diffusion method) were used. Non-iterative error diffusion with use of several specialized bypass matrices improves the quality up to 7%. Iterative realization of the error diffusion allows to increase quality to 15%.
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