Cory lay eggs on the glass like that and from what I have read chinese algae eaters are hard to breed in a normal community setting because they like strong currents and a lot of oxygen.
They are pretty dark, so either they are rotting or they are almost ready to hatch. The eggs hatch in 3 to 5 days normally.
If you pick one egg off the glass and it sticks to the glass on a different part, then it's probably for sure a cory egg. They are very sticky, just don't get them out of the water if you want them to hatch, even if you move them keep them in water at all times.