Delineating a Stream Network Based on NDWI Raster Values

[MichaelBrown3]

Ok, So this is my first post I have ever done on any forum ever. So follow me on this.....

I am working with high resolution Quickbird Satellite data with bands R,G,B, and IR. I am attempting to extract a stream network at the finest detail level the data will allow. My method right now is to spectrally resolve streams via band math. Overtone of the issue is that there is disconnection within the stream network and significant noise surrounding streams. Continue reading if interested with my problem.

Step 1).     I am using the raster calculator (Spatial Analyst --> Map Algebra) and am creating an output with the equation (float(Blue Band) - float(Red Band)) / (float(Blue Band) + float(Red Band)). The output is a NDWI raster. Streams are in this raster and I want to extract them.

Step 2). Reclassify the image into 3 classes based on Natural Jenks method. (Spatial Analyst --> Reclass --> Reclassify). I now have a "Deep water" or "Lakes" classification and a "streams" classification.

Step 3). I then Extract by Attribute (Spatial Analyst --> Extraction ) for both the "Deep Water" and "Streams" classes from the reclassification in order to have a separate raster with the spatial extent for both  "Deep Water" and "Streams" classes.

Step 4). I then Extract by Mask (Spatial Analyst --> Extraction) using the new individual reclass rasters for "Deep Water" and "Streams" as the masks to extract the actual NDWI pixel values within the spatial extent of the "Deep Water" and "Streams" classes.

Ste 5). Convert NDWI raster pixels to shapefile point data. (Conversion --> From Raster --> Raster to Point)

What do I do from here? I do not know how to connect the points or the raster images. I want a stream network but there are breaks all over the network. I have tried many different features and tools and cant seem to get the correct one. Buffer, aggregate, filter, etc. I am looking for a way to do this completely in Arc.

Pictures attached.

Thank you for your time.

[GlennAguilar]

Have you tried using ArcScan?

[MichaelBrown3]

Thank you for a timely reply. I am looking into Arc Scan right now and it is a very interesting tool. I am a moderate Arc user and there is still a plethora of things to know about this powerful software.

Pertaining to Arc scan though: Is there a way to completely remove the "background" cells? I want to have only the "foreground" or my "Water" Cells. I then want to have the NDWI raster active below the arc scan layer I am working with in order to perfectly "draw/paint" in the stream disconnects.

Is this possible? I cannot seem to delete the background cells.

[MichaelBrown3]

I found it. I simply turned the display color of the background class to "no color".

[MichaelBrown3]

So I have my stream networks now via arcscan. I am having an issue with vectorizing the finished raster products though. Something I must not be understanding about how the vectorization process works.

I have it set to center line. The stream lines are being delineated perfectly how I want them to be. It is the polygons (or lakes) that do not get vectorized. There is just an empty area with nothing vectorized there. How do I get these incorporated as well?

[GlennAguilar]

If you have the polylines (vectorize the boundary of the lakes to get the outline), you can then convert them to Polygon (Feature to Polygon).

[MichaelBrown3]

I have the network in raster, polyline, polygon, and point data. But I do not see how I would get stream order from feature to polygon? I want to create a field in the attribute table that says what each part of the network is.