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This article proposes to investigate how the reproduction of images impacted the conditions for the dissemination of scientific knowledge, based on strategies of representation and visual communication. As historical techniques of image reproduction, it is understood here the manual engraving of the matrix (i.e., xylography, chalcography and lithography) that preceded the photomechanical processes until the end of the 19th century. As a case study, the research was conducted by visual representations of the bird-of-paradise - an exotic bird, originating from islands in Southeast Asia, inaccessible to Europe at the time - addressing how it makes itself known to a wider audience, through printed images. Questions related to the modes of visual representation and graphic techniques will be addressed as fundamental attributes for understanding the theme, discussing their different languages, characteristics, limitations and potentialities for the domain and acquisition of knowledge mediated by information design. [ABSTRACT FROM AUTHOR]

Halftoning is an indispensable technique used for showing digital images on screen and printing them on paper using any kind of printer such as Inkjet and Laser. Additionally, halftoning technique has been employed recently in several applications in the computation and communication fields, such as compression and authentication of images, visual cryptography, etc. This article provides as detailed review of the main halftoning methods, such as ordered dither, error diffusion, error diffusion with edge emphasis, dot diffusion, green noise, and direct binary search. For analyzing advantages and disadvantages of each halfoning method, a quality comparison of the halftone image generated by the already named methods was performed using Mean Opinion Score (MOS) measurement. Likewise, computational complexity of each halftoning method was taken into consideration. [ABSTRACT FROM AUTHOR]