Joker -
As Webbot notes, it depends on resolution, but also the speed of the serial interface. The SRV-1 Blackfin transmits JPEG, and a typical 320x240 frame is 5-10kbytes (40-80kbits), so after you add compression time (25 fps), at 115kbps you end up with 1-2 fps. If you have a higher speed interface such as Matchport wifi which runs at 2.5Mbps (actual throughput closer to 1.7Mbps), the frame rates at this resolution end up closer to 10-15fps range.