Occam's Aftershave
Posts: 5287
Joined: Feb. 2006
|
| Quote (Joe G @ Mar. 29 2018,15:05) | | Quote (Occam's Aftershave @ Mar. 29 2018,15:01) | | Quote (Joe G @ Mar. 29 2018,14:45) | | Tree ring widths are part of the data. You can't scan them and get some reading like we do actual barcodes. |
Yes dumbfuck, we can scan them like we do barcodes
| Quote | WinDendro Image Analysis for Plant Science
The first step of tree-ring analysis is image acquisition. WinDENDRO has been designed and is optimised for optical scanners but can also analyse images from cameras and digital filmless x-ray systems. It can open image files produced by these hardware manufacturers programs (provided they are saved in a standard format such as jpeg or tiff), but most of the time WinDENDRO is used to acquire images directly from such devices (when they are TWAIN compatible*). Optical scanners are particularly well adapted for tree-rings analysis. They produce high quality images over large areas.
WinDENDRO deals with scanners in a very efficient way. It has two methods of image acquisition for them, one is optimised for ease of use and requires just a mouse click to get an image. Time is saved in bypassing the standard "Preview" step (which can take tens of seconds per sample) and by using positioning accessories which allows to repetitively place the samples at the right place on the scanner. The other scanning method is more complex and powerful, it uses the Preview step to optimise the scanning parameters.
After image acquisition, you indicate WinDENDRO where to measure rings in the image. This is done by tracing paths interactively. Straight line paths (such as those extending from a disk pith to bark) can be created automatically with a single mouse click (up to a few hundreds in a single click). More complex shape paths (see below) are created manually by clicking at different places
After paths have been created, rings are automatically detected by WinDENDRO and their presence is indicated over the image with lines and text. Lines indicate the rings boundary position and orientation and the text indicates the year and ring number. Earlywood width can also be displayed along with other ring features (explained next). Close to the image, a profile of the light variations inside the path is also displayed along with ring and earlywood widths. This region is also used to adjust the sensitivity of the automatic ring detection. The sensitivity of this initial detection can be adjusted in function of the rings appearance. Narrow and low contrasts rings require more attention.
One or two methods of ring detection are provided in function of the WinDENDRO software model. The first method is based on light intensity differences. It is simple, efficient and works fine for contrasted rings like those of conifers. The other ring detection method is called Teach & Show and is a method where you show to WinDENDRO what a tree ring is in the image so that it can automatically detect them after. This method is more computer intensive and is well adapted for low contrasted rings like those of deciduous trees. There are limits however and minimal contrast is required in order to get a good level of automatic detection. When contrast is too low, you can work in manual mode where you indicate the position of rings in the image by clicking them. |
Joke the dumbass strikes again!
 |
No, that is not like a barcode reading. |
Oh dear, Joke shits his pants every time he's proven wrong. The smell in his basement must be horrific.
--------------
"CO2 can't re-emit any trapped heat unless all the molecules point the right way"
"All the evidence supports Creation baraminology"
"If it required a mind, planning and design, it isn't materialistic."
"Jews and Christians are Muslims."
- Joke "Sharon" Gallien, world's dumbest YEC.
|
