Thursday, February 15, 2018

USA news on Youtube Feb 16 2018

This video was produced by students for training purposes only and is provided on an "as is" basis

ISU and the state of Idaho make no warranties about the completeness

reliability usefulness or accuracy of this information

Any action you take upon the information provided is strictly at your own risk and ISU and the state of Idaho

Will not be liable for any errors omissions losses or damages in connection with the use of the content of this video

This video demonstrates methods for lava train analyses that can be performed in arcmap

Using a high resolution digital surface model that was produced in the previous video

After opening arcmap go into the catalog

Right-click the location where you want to save your work, and then click new file geodatabase and type in the name

This is where you'll save all of the files you create

now click the add data button and navigate to the digital surface model and

Then click Add to bring your DSM into arcmap

In the table of contents

Left click the white to black color ramp to change the colors

Choose a new color gradient in this case

I chose red to blue and inverted the colors so that red represents high elevation values and

Blue represents low values. Now we'll start analyzing the terrain

I'm zooming in to help see the details of the DSM

Now we'll build a hill shade to help visualize the terrain. In the search box type hillshade

Click the hill shap tool in

The input raster select the DSM

Give the file a name

And click okay

Next we'll calculate the steepness of the slopes in the DSM

In the search box type in slope and

click the slope tool

In the input raster select the DSM

Give the file a name

And click okay

Next we'll calculate the direction that the slopes face in the search box type in aspect

click the aspect tool

In the input raster drop down menu select the DSM

Give the file a name and press ok

Last we will calculate the ruggedness of the terrain using a terrain ruggedness index this index requires a neighborhood

calculation for the minimum and maximum

over 3x3 area

For the minimum in a search box type in block statistics

click block statistics in the input raster drop-down box select the dsm

Name your output raster min use a 3 by 3 neighborhood

select minimum from the statistics type drop-down box and click OK

For the maximum in the search box click block statistics again in

the input raster drop-down box select the dsm

Name your output raster max

Use a 3 by 3 neighborhood

select maximum from the statistics type drop-down box and click OK

To calculate the terrain index go into the search box and type raster calculator

click raster calculator

Now click on the terms to input the mathematical expression

Select the square root inside of the square root and select the absolute value

Inside of the absolute value select square

inside of the square select the max raster

back inside of the absolute value after the squared max select minus

after the minus select square

inside of the square select the min raster

Give the file a name

and click OK

For more infomation >> Using DSMs and Orthophotos produced from UAS imagery: Part 2 - Duration: 6:19.

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Man who warned FBI of Florida shooter speaks out - Duration: 3:42.

For more infomation >> Man who warned FBI of Florida shooter speaks out - Duration: 3:42.

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Source: Mitt Romney to announce Senate run on Friday - Duration: 2:09.

For more infomation >> Source: Mitt Romney to announce Senate run on Friday - Duration: 2:09.

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Quick-thinking, bravery saves lives in Fla. school shooting - Duration: 3:06.

For more infomation >> Quick-thinking, bravery saves lives in Fla. school shooting - Duration: 3:06.

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School shooting renews gun control vs. mental health debate - Duration: 8:32.

For more infomation >> School shooting renews gun control vs. mental health debate - Duration: 8:32.

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Development of DSMs and Orthophotos from UAS imagery using Agisoft Photoscan: Part 1 - Duration: 5:46.

This video was produced by students for training purposes only and is provided on an "as is" basis

ISU and the state of Idaho make no warranties about the completeness reliability usefulness or accuracy of this information

Any action you take upon the information provided is strictly at your own risk and ISU and the state of Idaho

Will not be liable for any errors omissions losses or damages in connection with the use of the contents of this video

This video demonstrates how to stitch UAS images together in agisoft photoscan to produce a digital surface model and an orthomosaic image of a lava flow

After opening agisoft add photos by clicking workflow and add photos

Navigate to a folder that contains all of the photos that you want to include in the model

Select all photos by holding down ctrl and pressing a and click open

After photos are added use low alignment to match overlapping portions of the images and create a preliminary sparse cloud

Click workflow and align choose the low setting and click OK

To reduce error in the model we will create and place markers on the images

Right-click on a recognizable feature in an image and click create marker and note the marker number in this case. It is marker 5

Now navigate to another image that has the same feature and either move the predicted marker location to the correct location

Or right-click on the feature and select place marker then choose the correct marker number

Cycle through all of the photos to make sure that the marker is correctly placed on any image that contains it

If we know the distance between two markers we can use this to create a measured scale

Highlight the two points with a known distance in your reference tab

Right-click the selection and click create scale and a new scale bar will show up in the scale bar our window

Click once on the blank area below distance, and then type the known distance in meters

Now perform a high alignment to produce and improved sparse cloud

click on workflow and then align photos

Choose the high setting and click OK

Now gradually select erroneous points in the sparse cloud to improve the accuracy

click Edit and then

gradual selection

Select a reprojection error and adjust the bar below to change the number of points that will be selected

Click OK, and then press Delete on the keyboard

to remove these points

Click Edit and gradual selection again

Except this time select reconstruction uncertainty adjust the bar below to change the number of points that will be selected

Click OK and then press Delete on the keyboard to remove these points

Click Edit and gradual selection again and then select projection accuracy

Adjust the bar below to change the number of points that will be selected

click OK and

Then press Delete on the keyboard to remove those points

Monitor to the number of projections that remain in the model do not let the lowest number fall below 100

Now that the sparse point cloud quality is improved build the dense point cloud click workflow

Then select build dense cloud make sure the quality is set to high and the depth field is set to aggressive press ok

Build a mesh that's based off your dense point cloud by clicking workflow and selecting build mesh

Change the surface type to height field change the surface data to dense cloud change the face count to high

Expand the advanced settings and disable interpolation click OK to build the mesh

The final piece of the model is to build the texture click workflow and select build texture

Set mapping mode to orthophoto

Expand the Advanced Settings and make sure color correction and hole filling are unchecked

And click okay

Now build out the DSM

Click workflow and select build DEM

Make sure that the source data is set to dense cloud and click OK

Now build the orthophoto

click workflow and select build orthomosaic

Set the surface to DEM and

click OK

Export the DEM in the reference tab right click on the DEM and click export DEM

select export TIFF/Bil/XYZ in the next screen click export give the file a name

Click Save

Export the orthomosaic back in the reference tab

right click orthomosaic and click export orthomosaic

Select export TIFF/Bil/XYZ in the next screen click export give the file a name

Click save

The next video in the set will demonstrate lava terrain analyses that can be performed using the digital surface model

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