| Returns an elapsed-seconds counter as an image. |
| Convert localTime to a string and ignore fractional part. |
| render into an image |
| Scale into a unit square [0,1]. Note that as the size of the the string grows, for example going from 1 digit to 2, the scale adapts to fit the resulting image in the unit square. |
| This is a time-varying solid-colored image, infinite in extent. |