VO1/VO2 MARS VISUAL IMAGING SS EXPRMNT DATA REC BROWSE V2.0

This data set includes sub-sampled versions of Viking Orbiter images that are intended to facilitate rapid viewing of the image collection. The image data in these browse images have been reduced in size by sub-sampling the original image by a factor of 4 in both lines and samples. Thus, the data volume has been reduced by a factor of 16. A Viking Orbiter browse image contains 264 lines and 300 samples. A filtering procedure was used in generating the browse images because Viking Orbiter images commonly contain noisy data or are missing data. The brightness value of a pixel in a browse image is the median brightness value of an array of 4 by 4 pixels from the original image. If the 4 by 4 array of original pixels contained zero values, those zero value pixels were not used in determining the median value. Of course, if the entire 4 by 4 array contained zero value pixels, the corresponding pixel in the browse image was assigned a zero value.