Areas with moving and unidentied clouds require more elaborate masking algo-rithms to remove these degraded retrievals. Cloud motion can also aect regions with unidentied clouds thin or fractional clouds that evade the cloud identication process yielding degraded quality in retrieved ocean colour parameters. This approach reduces the amount of masking required versus a simple expansion of the mask in all directions away from clouds. Inter-band correlations can be used to measure the amount of cloud shift, which can then be used to adjust the cloud mask so that the union of all shifted masks can act as a mask for all bands. The length of time it takes to acquire all eight GOCI bands for a given slot (portion of a scene) is sucient to require that cloud motion be taken into account to fully mask or correct the eects of clouds in all bands. The Geostationary Ocean Colour Imager (GOCI) instrument, on Koreas Communications, Oceans, and Meteorological Satellite (COMS), can produce a spectral artefact arising from the motion of clouds the cloud is spatially shifted and the amount of shift varies by spectral band. This counterintuitive result held for both natural and man-made scenes (but not for scenes without nameable gist) and thus corroborates the shift from more detailed processing of images in greyscale to more gist-based processing of coloured images.Ĭloud Motion in the GOCI COMS Ocean Colour Data The results show that changes to images are detected faster when image-pairs were presented in greyscale than in colour.
In the final experiment we specifically targeted the more detail-based perception and recognition for greyscale images versus the more gist-based perception and recognition for coloured images with a change detection paradigm.
A second experiment, utilizing images without a nameable gist, confirmed this hypothesis as participants now performed equally on greyscale and coloured images. We hypothesized that this increase in false alarm rate was due to a shift from scrutinizing details of the image to recognition of the gist of the ( coloured) image. Surprisingly, performance was better for greyscale than for coloured images, and this difference is due to the higher false alarm rate for both natural and man-made coloured scenes. Participants were asked to indicate whether they had seen the images during the study phase. Next, the same images were presented, randomly mixed with a different set. In the first experiment participants first studied a set of colour and greyscale natural and man-made scene images. Here we investigate whether colour can also facilitate memory for scene images, and whether this would hold for natural scenes in particular. Nijboer, Tanja C W Kanai, Ryota de Haan, Edward H F van der Smagt, Maarten JĬolour has been shown to facilitate the recognition of scene images, but only when these images contain natural scenes, for which colour is 'diagnostic'. Recognising the forest, but not the trees: an effect of colour on scene perception and recognition. Our data thus support the hypothesis that the effect of colour occurs at the level of learned associations. However, for the natural scenes, appropriate colour facilitated scene recognition in control participants (i.e., shorter reaction times), whereas M.A.H.'s performance did not differ across formats.
nor control participants showed any difference in performance for the non-natural scenes. was much slower on the natural than on the non-natural scenes. In a scene identification task, participants had to name images of natural or non-natural scenes in six different formats. We investigated the effect of colour on scene recognition in a case of colour agnosia, M.A.H. It has been suggested that colour supports low-level sensory processing, while others have claimed that colour information aids semantic categorization and recognition of objects and scenes. Scene recognition can be enhanced by appropriate colour information, yet the level of visual processing at which colour exerts its effects is still unclear. Nijboer, Tanja C W Van Der Smagt, Maarten J Van Zandvoort, Martine J E De Haan, Edward H F Colour agnosia impairs the recognition of natural but not of non-natural scenes.