An arbitrary example:
Create a random image
Image[RandomReal[{0, 1}, {10, 10}], ImageSize -> Medium]
Define some points and a graph to align
c = PixelValuePositions[%, White, .1]
RandomGraph[Table[Length[c], 2]]
Out[1]: {{2, 9}, {1, 8}, {1, 7}, {2, 7}, {9, 6}, {2, 2}}
How can I align the nodes of a graph to coordinates on an image?
Ideally this would be a graph from a correlation matrix
RandomReal[{-1, 1}, Table[Length[c], 2]] // MatrixForm