IR sensor interface

BitSim has developed a receiver for FLIR’s Video over SPI (VoSPI), an interface to enable streaming images from a Lepton Infrared camera directly to an FPGA-based image processing system. You can use it in your platforms like:

  • On Xilinx devices with our new customized IP.
  • On every SoC circuit with an ARM CPU and Python with our pure-software driver.
  • A Python interface which integrates the VoSPI IP in your PYNQ design.

VoSPI stands for “Video over Serial Peripheral Interface”. VoSPI protocol is designed to send out the video in a format that allows transmission over a SPI interface while requiring minimal software or hardware. The sensor acts as SPI slave and the hardware acts as SPI master and the video is streamed on MISO pin. The hardware system uses custom logic to receive and render the video. The sensor sends out bytes of pixels through packets and segments to form a frame of 160×120 resolution.

The development of this IP has been done on BitSim’s Python-based development platform, SpiderPig board. Utilizing this simple interface between the Logic fabric and the high-level Python environment, debug information and image analysis could be performed almost directly after a bitfile is generated. BitSim has developed tools for Thermal Imaging and specifically to integrate the FLIR Lepton sensor by using VoSPI.

Using this IP block, it is possible to attach a low cost FLIR Lepton IR sensor, which sends processed 16-bit data to an FPGA design. The IR sensor captures infrared radiation as input. The output is a uniform thermal image with temperature measurements throughout the image. This can be used in applications such as Mobile phones, Gesture recognition, Building automation, Thermal imaging and Night vision where detection of temperature values and high temperature scenes are necessary.

IR video over SPI
Thermal image of  a person holding a hot coffee captured by Lepton 3.5 IR sensor.