Photoshop CS6.1 allows you to add Field Blur, Iris Blur and Tilt-Shift effects to Smart Objects, which mean that you can also use them with video layers. Here’s how.
Drag your video into Photoshop CS6.1. Right-click it in the Layers panel and select Convert to Smart Object.
Add an Iris blur (Filter > Blur > Iris Blur…). Use the on-screen controls to position it and adjust it to fit your footage. Here we’ve rotated it slightly, tightened the inner ring and expanded the outer slightly. This makes the flower really stand out.
The final effect is applied to the whole clip. Unfortunately the blur’s parameters cannot be keyframed over time, which is fine for this largely static clip. Anything more complex requires Premiere Pro.