In our various leaf herbivory papers we used Sigmascan. The drawing-round damaged areas was done by hand using the mouse. It is tedious, but we preferred to keep the human element in to avoid computer errors. Complex temperate zone leaf shapes (e.g. many oaks) are especially hard for a computer to cope with.
Jonathan --- Original Message --- From : "malcolm McCallum" To : [email protected] Date : 2010/12/11 Saturday PM 2:59:01 Subject : Re: [ECOLOG-L] quantifying leaf damage from scanned leaves Use ArcView! Just count the pixels of leaf versus missing leaf. You can actually consolidate the colors to strait out black (leaf) and white (missing leaf) then tabulate the pixels in black versus white. If you want more detailed you can use a more complex color array to indicate areas that are damaged but still present. Malcolm On Fri, Dec 10, 2010 at 9:07 PM, Stratford, Jeffrey -- Malcolm L. McCallum Managing Editor, Herpetological Conservation and Biology "Peer pressure is designed to contain anyone with a sense of drive" - Allan Nation 1880's: "There's lots of good fish in the sea"? W.S. Gilbert 1990's:? Many fish stocks depleted due to overfishing, habitat loss, ? ? ? ? ? ? and pollution. 2000:? Marine reserves, ecosystem restoration, and pollution reduction ? ? ? ? ? MAY help restore populations. 2022: Soylent Green is People! Confidentiality Notice: This e-mail message, including any attachments, is for the sole use of the intended recipient(s) and may contain confidential and privileged information.? Any unauthorized review, use, disclosure or distribution is prohibited.? If you are not the intended recipient, please contact the sender by reply e-mail and destroy all copies of the original message.
