img = CloudGet["https://www.wolframcloud.com/obj/5a37cec8-5245-45a4-aa78-4319ed0a21ce"];
data=ImageData[ImageAdjust@img,"Real"];
lines=Line[MapIndexed[Reverse[#2]+{0,#1*30}&,Reverse@data,{2}][[1;;-1;;5]]];
Graphics[
{Inset[img, {1, 1}, {1, 1}, ImageDimensions[img]], lines},
PlotRange -> {{1, 274}, {1, 240}}]