Slide 1

Systemy wizyjne
Vision systems

Laboratory 1

High speed camera test stand

ISSUES:

1. Camera technical parameters, camera usage, record modes & settings ,
- rate vs. exposure, aperture vs. exposure, acquisition settings (record modes)

Lecturer: Piotr Kohut, PhD eng.

Date:

Grade

Students' names:

Idea of this test stand is to record an object in
motion.

Then using a proper software analyse

this images and gain data (position x,y,z and
orientation yaw,pitch,roll) describing motion of this
object is 3D space.

Idea of test stand

Test stand procedure

Test stand procedure is divided into 3 main parts:



Lab_1_Image aquisition

– using Motion Studio



Lab_2_Camera calibration

– using GML Camera

Toolbox



Lab_3_Image analysis, trajectory tracking,
displaying results

– using Tema software

Test stand



A model to track, with
quadrant markers placed
at known positions



scene

uniform

background for a model



Camera

recording

marked

walls

the

model



Lighting - as close to the
model as possible and
aproximately

along

the

axis of camera

Motion Studio



Main feature

– acquisition of the sequence

of images recorded by the high-speed
camera



Setting the parameters of recording, such
as frequency rate, exposure time, region of
interest



Simple image processing, filters.



Internal or external trigger

Motion Studio

1. Open

camera

2. Camera

control - Live

3. Acquisition

settings -

Camera

4. Set

aperture

5. Set rate and

exposure

6. Position the

model

7. Adjust the

focus

8. Acquisition

settings

–

Record

9. Camera

control -

playback

10. Save

acquisition

Motion Studio

1. Open camera. Select all the available types of cameras.

1. Open

camera

2. Camera

control - Live

Motion Studio

Choose the X-Stream XS3 camera, USB 2.0

1. Open

camera

2. Camera

control - Live

Motion Studio

2. Camera control - Live

•

Rec - switches record mode on. However, it does not
starts acquiring

•

Trigger - while in record mode, sets the moment of
acquisition

•

Live - sends live preview from the camera onto the
screen, but not records images

•

Stop

Now, choose Live mode.

1. Open

camera

2. Camera

control - Live

3. Acquisition

settings -

Camera

Motion Studio

3. Acquisition settings - Camera



Rate - number of frames per second.



Exposure - time of acquisition of a single
frame in microseconds. It can be adjusted
by the buttons -1/2f and 1/2f.
Maximum time is determined by set Rate.
The higher rate, the lower maximum
exposure time. Longer exposure provides
more light and brighter image; shorter -
darker image.



Low light mode (

) - Temporarily sets

Rate to 25Hz and exposure to four times the
current value. It is useful for preview in low-
light conditions.



ROI - region of interest - Sets the area of
frames, we want to acquire. Maximum is
1280x1024. Number of lines determines the
maximum Rate. For largest ROI, maximum
rate is 610Hz

2. Camera

control - Live

3. Acquisition

settings -

Camera

4. Set

aperture

Motion Studio

ROI - region of interest

Sets the area of
frames, we want to
acquire. Maximum is
1280x1024. Number
of lines determines
the maximum Rate.
For largest ROI,
maximum rate is
610Hz

2. Camera

control - Live

3. Acquisition

settings -

Camera

4. Set

aperture

Motion Studio

4. Adjusting aperture



Should be relatively high
to provide high depth of
field and ensure that all
markers will be tracked
properly



On the other hand
higher aperture reduces
amount of light and
longer exposure time
has to be set



Set the value from 4 to 8

3. Acquisition

settings -

Camera

4. Set

aperture

5. Set rate

and exposure

Motion Studio

5. Choosing appropriate rate and exposure

For high precision of tracking a movement, it is
good to provide as high rate as possible. However,
you have to provide enough light. Because of this,
set maximum exposure for given rate.

Appropriate
amount of light

4. Set

aperture

5. Set rate

and exposure

6. Position the

model

Motion Studio

Too much light

Too little light:

4. Set

aperture

5. Set rate

and exposure

6. Position the

model

Motion Studio

6. Positioning of a model:



Model should occupy major part in the centre of a frame.



All three walls should be equally, well visible. The closer to
perpendicular they are, the more reliable tracking is. Three markers,
which are most difficult to be tracked properly are marked on the
image:

5. Set rate

and exposure

6. Position

the model

7. Adjust the

focus

Motion Studio

7. Adjusting the focus



After positioning of a model, the focus
has to be adjusted on the lens of the
camera. It has to be set so, that
images of all the markers: the closest
to the camera, as well as furthest
ones, has to be equally sharp.



ATTENTION! Focus cannot be
changed between acquiring the
sequence and calibration!

6. Position

the model

7. Adjust the

focus

8. Acquisition

settings

–

Record

Motion Studio

Bad focused image

Well focused image

6. Position

the model

7. Adjust the

focus

8. Acquisition

settings

–

Record

Motion Studio

8.Acquisition settings

– Record

Record mode:



Normal - the camera acquires and
stops when assumed number of
frames was recorded



Circular - enables to acquire
frames which occurred before and
after "Trigger" button. Length of pre-
and post-trigger can be adjusted by
Trigger Adjust



BROC (Burst Record on
Command) - enables to acquire
several sequences in one record,
each at the time of trigger.

7. Adjust the

focus

8. Acquisition

settings

–

Record

9. Camera

control -

playback

Motion Studio

Choose circular
mode, set the
number of frames to
obtain sequence of
length 0.5s - 1s, set
pre-trigger to, e.g.
25% of length.

Record and trigger

7. Adjust the

focus

8. Acquisition

settings

–

Record

9. Camera

control -

playback

Motion Studio

9. Camera control -

playback

A sequence after
acquisition can be
played with a Play
button. The speed can
be adjusted with a
slider

8. Acquisition

settings

–

Record

9. Camera

control -

playback

10. Save

acquisition

Motion Studio

10. Saving acquisition

Use "Save Acquisition" button (marked with red rectangle).
You can choose folder, name for files and format.

9. Camera

control -

playback

10. Save

acquisition