How do I create a boundary for my raster/polygon layer?

[JeromeWu]

Hi folks, I am trying to perform a walkability analysis for Sacramento, CA. I converted the service area polygon shapefiles for each locations in Sacramento into raster layers. However, I need to have my raster layers within a boundary like the figure on the left, so I can define raw raster values of 0-1. Right now, my polygon shapefiles & raster layers are stand alone so they only have a single value of 1. 

Does anyone know how to do this? Am I supposed to create the boundary with the service area polygons before I convert them to raster? 

Thank you!

[m_neer]

If you are trying to create a 'boundary" from the raster you can use the "raster to polygon" GP tool found in the conversions tools set->From Raster-> "Raster to Polygon" 

If you are trying to Clip them based on a boundary just do a "clip raster" GP tool.  found in Raster->Raster Processing->"Clip Raster"

Clip Raster—Data Management toolbox | Documentation 

Raster to Polygon—Conversion toolbox | Documentation 

[JeromeWu]

I figured it out. I had to Reclassify my raster layers and specify the processing extent and raster analysis mask.

Thanks!