Import Sprite Strip dialog
This dialog allows you to import an image containing an entire animation in a grid. It is accessed via the Animation Frames bar. After choosing the Import sprite strip... option, a dialog appears to select the image file. After a file has been chosen, this dialog appears to tell Construct 2 how many animation frames are in the image.
For example, the following image has 7 horizontal cells and since they are all on one row, only 1 vertical cell:
The following image is in a grid, so has 4 horizontal cells and 4 vertical cells:
In both cases Construct 2 will separate each cell in the image to a different animation frame.