FLIR blackfly s industrial camera: configure multiple cameras for synchronous shooting

Flir Blackfly S Introduction to industrial camera

Blackfly S Adopt the advanced ice shape sensor in the industry .
It's powerful , You can easily generate the exact image you need , And accelerate application development .
Including automatic and precise manual control of image capture and camera preprocessing .
Blackfly S Provide GigE、USB3、 Suit and board versions .
Accurate image SONY CMOS Choices among sensors include ： Global shutter 、 Polarization and high sensitivity BSI sensor .

The physical drawing is as follows ：

Synchronous shooting concept

Synchronous shooting refers to two or more cameras capturing images at the same time
“ meanwhile ” It means that the camera must start exposing each group of images within a few microseconds

Here is how to use the strobe of the main camera （ When the camera starts capturing images, there is a strobe by default ） Through one “ Lord ” The camera triggers another or more “ vice ” camera . This also ensures that the frame rate of the sub camera is the same as that of the main camera .

Another method can also trigger multiple cameras by external hardware at the same time to achieve the above functions

Synchronously shoot application scenes

The synchronous shooting application can be spliced with multiple cameras , Or multi camera detection in the field of autonomous driving . For example, the camera carrier moves faster , The exposure time deviation of multiple cameras is large , There will be no splicing . So synchronous shooting is still very important in application .

Flir Blackfly S Synchronous shooting method

The synchronous shooting method is mainly divided into two steps ：

• Connect the camera GPIO Pin , Establish hardware connection between cameras .
• Use SDK Demonstrate the application or code to configure the input and output of each camera .
  Next, we will introduce each step in detail

Establish hardware connection between cameras

The first step is to establish a hardware connection between cameras .
Blackfly S （BFS ） The camera is equipped with a 6 The needle GPIO. BFS GPIO At the same time, it is equipped with a non isolated output and a photoelectric isolated output . If photoelectric isolation output is used , The main camera needs a pull-up resistor to enhance its flash signal .

BFS The camera is equipped with a 6 The needle GPIO The definition is as follows

You want to configure BFS Main camera and sub camera ：

• Turn the number of the main camera 4 The needle （ White line , Photoelectric isolation output ） Connected to the No. of each sub camera 1 The needle （ The green line , Non isolated input ）.
• Turn the number of the main camera 5 The needle （ The blue line , Photoelectric isolation ground wire ） Connected to the No. of each sub camera 6 The needle （ Brown line , Ground wire ）.
  To configure the required pull-up resistance to enhance the signal ：

• take 10 kΩ One end of the resistor is connected to the first... Of the main camera 3 The needle （ Red thread ,3.3 V Output ）.
• Connect the other end of the resistor to the second end of the main camera 4 The needle （ White line ） And the number of each sub camera 1 The needle （ The green line ）.
• Turn the number of the main camera 6 The needle （ Brown line ） Connected to the No. of each sub camera 6 The needle （ Brown line ）. Be careful ： Sub camera No 6 The pin is connected to the... Of the main camera 5 The needle .

Configure the camera software

After hardware connection of each camera , Use Upper computer To configure the GPIO Line .
The upper computer is SpinView

Main camera

• open SpinView.
• Select the camera .
• On the function tab , Click number IO control .
• Select... From the line selection drop-down menu line 1, Then set the line mode to output .
• Enable 3.3V Line select a line from the line selection drop-down menu 2, And check the 3.3V Enable the check box
• Save settings in user settings

Secondary camera

• open SpinView And select the camera .
• choice GPIO tab . Set trigger source from the trigger source drop-down menu , choice line 3.
• From the trigger overlap pull list , Select read .
• From the trigger mode drop-down list , Choose to open .
• Save settings in user settings

Start saving images at the same time

After configuring the main camera and sub camera , You can start saving the synchronized image .

If you save images with high bandwidth , It is recommended to use the controller application instead of the upper

If you use SpinView The method is as follows ：

• Make sure that the trigger mode of the main camera is turned on .
• In the streaming window of the main camera , Click the record button .
• Modify the recording settings as needed .
• Click the start recording button .
• Keep the recording window open .
• For the sub camera , Repeat the first 1 Step to the top 5 Step .
• Turn off the trigger mode of the main camera . This will start the shooting of two cameras .

If you use your own controller, you can combine Spinnaker SDK Example code for

AcquisitionMultipleCameraTrigger

Position in Example: C:\Program Files\Point Grey Research\Spinnaker\src

When using these cameras for synchronous shooting , The flash must be turned on . Turn on strobe , You can use the following code to create a StrobeControl Structural examples ：

StrobeControl strobe;

strobe.source = 2;

error = cam.GetStrobe(&strobe);

strobe.onOff = true;

error = cam.SetStrobe(&strobe);

Problems encountered and Solutions

The frame rate of the sub camera when capturing images is half that of the main camera

** reason ：** The secondary camera does not use overlap trigger
** Solution ：** On the auxiliary camera , Switch to using “ Trigger overlap ”.

The sub camera takes images at a very low frame rate

** reason ：** Camera exposure （ Shutter ） The value is too large .
** Solution ：** Exposure can be adjusted （ Shutter ） Time .
stay SpinView in Settings On the tab