Baumer VisiLine IP User's Guide for Gigabit Ethernet Cameras Document Version: Release: Document Number: v1.5 15.09.
Table of Contents 1. General Information ������������������������������������������������������������������������������������������������� 6 2. General safety instructions ������������������������������������������������������������������������������������� 7 3. Intended Use ������������������������������������������������������������������������������������������������������������� 7 4.
9.2 Color Processing ��������������������������������������������������������������������������������������������������� 36 9.3 Color Adjustment – White Balance ����������������������������������������������������������������������� 36 9.3.1 User-specific Color Adjustment ���������������������������������������������������������������������� 36 9.3.2 One Push White Balance ������������������������������������������������������������������������������� 37 9.
10.9 Message Channel ����������������������������������������������������������������������������������������������� 62 10.9.1 Event Generation ����������������������������������������������������������������������������������������� 62 10.10 Action Command / Trigger over Ethernet ���������������������������������������������������������� 63 10.10.1 Example: Triggering Multiple Cameras ������������������������������������������������������ 63 11.
1. General Information Thanks for purchasing a camera of the Baumer family. This User´s Guide describes how to connect, set up and use the camera. Read this manual carefully and observe the notes and safety instructions! Target group for this User´s Guide This User's Guide is aimed at experienced users, which want to integrate camera(s) into a vision system.
2. General safety instructions Caution Heat can damage the camera. Provide adequate dissipation of heat, to ensure that the temperatures does not exceed the value (see Heat Transmission). As there are numerous possibilities for installation, Baumer does not specify a specific method for proper heat dissipation. 3. Intended Use The camera is used to capture images that can be transferred over a GigE interface to a PC.
4. General Description 1 2 3 5 4 No. Description No.
5. Camera Models Sensor Size Resolution Full Frames [max. fps] VLG-02M.I / VLG-02C.I 1/4" 656 x 490 160 VLG-12M.I / VLG-12C.I 1/3" 1288 x 960 42 VLG-20M.I / VLG-20C.I 1/1.8" 1624 x 1228 27 Camera Type CCD Sensor (monochrome / color) CMOS Sensor (monochrome / color) VLG-22M.I / VLG-22C.I 2/3" 2044 x 1084 55 VLG-40M.I / VLG-40C.
6. Installation Lens mounting Notice Avoid contamination of the sensor and the lens by dust and airborne particles when mounting the support or the lens to the device! Therefore the following points are very important: ▪▪ Install the camera in an environment that is as dust free as possible! ▪▪ Keep the dust cover (bag) on camera as long as possible! ▪▪ Hold the print with the sensor downwards with unprotected sensor. ▪▪ Avoid contact with any optical surface of the camera! 6.
6.3 Mechanical Tests Environmental Testing Standard Parameter Vibration, sinusodial IEC 60068-2-6 Search for Resonance 10-2000 Hz Amplitude underneath crossover frequencies 1.5 mm Acceleration 10 g Test duration 150 min Frequency range 20-1000 Hz Acceleration 10 g Displacement 5.
7. Pin-Assignment 7.1 Power Supply and Digital IOs Power supply / Digital-IO (SACC-CI-M12MS-8CON-SH TOR 32) /wire colors of the connecting cable) 3 2 4 8 1 7 5 6 1 OUT 3 white 7 Power GND blue 2 Power Vcc+ brown 8 OUT 2 red 3 IN 1 green 4 IO GND yellow Notice 5 Uext OUT grey 6 OUT 1 pink The electrical data are available in the respective data sheet. 7.2 Ethernet Interface (PoE) Notice The VisiLine IP supports PoE (Power over Ethernet) IEEE 802.3af Clause 33, 48V Power supply.
8. Product Specifications 8.1 Spectral Sensitivity The spectral sensitivity characteristics of monochrome and color matrix sensors for VisiLine IP cameras are displayed in the following graphs. The characteristic curves for the sensors do not take the characteristics of lenses and light sources without filters into consideration. 10 10 08 08 Relative Response Relative Response Values relating to the respective technical data sheets of the sensors. 06 04 02 0 400 500 VLG-02M.
Quantum Efficiency [%] Quantum Efficiency [%] Figure 7 ► Spectral sensitivities for Baumer cameras with 5.0, 4,0 MP CMOS sensor. 350 450 550 VLG-22M.I / VLG-40M.I 650 750 850 950 1050 Wave Length [nm] 350 450 550 VLG-22C.I / VLG-40C.
8.2 Field of View Position The typical accuracy by assumption of the root mean square value is displayed in the figure and the table below: ±α 0,5 ±YM ±XR ±YR 0,5 ±XM 60,2 15,6 7,2 photosensitive surface of the sensor cover glas of sensor thickness: D front cover glass thickness: 1 ± 0.1 mm 14,6 A gure 8 ► of the P ±Z optical path c-mount (17.526 mm) Camera Type ± XM [mm] ± YM [mm] ± XR [mm] ± YR [mm] ± zZyp [mm] ± αtyp [°] A [mm] D** [mm] VLG.I-02* 0.09 0.09 0.09 0.09 0.025 0.
8.3 Acquisition Modes and Timings The image acquisition consists of two separate, successively processed components. Exposing the pixels on the photosensitive surface of the sensor is only the first part of the image acquisition. After completion of the first step, the pixels are read out. Thereby the exposure time (texposure) can be adjusted by the user, however, the time needed for the readout (treadout) is given by the particular sensor and image format.
8.3.2 Fixed-Frame-Rate Mode With this feature Baumer introduces a clever technique to the VisiLine IP camera series, that enables the user to predefine a desired frame rate in continous mode. For the employment of this mode the cameras are equipped with an internal clock generator that creates trigger pulses. Notice From a certain frame rate, skipping internal triggers is unavoidable. In general, this depends on the combination of adjusted frame rate, exposure and readout times.
8.3.3 Trigger Mode After a specified external event (trigger) has occurred, image acquisition is started. Depending on the interval of triggers used, the camera operates non-overlapped or overlapped in this mode.
8.3.3.2 Overlapped Operation: texposure(n+2) > texposure(n+1) If the exposure time (texposure) is increased from the current acquisition to the next acquisition, the time the camera is unable to process occurring trigger signals (tnotready) is scaled down. This can be simulated with the formulas mentioned above (no. 2 or 4, as is the case).
8.3.3.3 Overlapped Operation: texposure(n+2) < texposure(n+1) If the exposure time (texposure) is decreased from the current acquisition to the next acquisition, the time the camera is unable to process occurring trigger signals (tnotready) is scaled up. When decreasing the texposure such, that tnotready exceeds the pause between two incoming trigger signals, the camera is unable to process this trigger and the acquisition of the image will not start (the trigger will be skipped).
8.3.3.4 Non-overlapped Operation If the frequency of the trigger signal is selected for long enough, so that the image acquisitions (texposure + treadout) run successively, the camera operates non-overlapped.
8.3.4 Advanced Timings for GigE Vision® Message Channel The following charts show some timings for the event signaling by the asynchronous message channel. Vendor-specific events like "TriggerReady", "TriggerSkipped", "TriggerOverlapped" and "ReadoutActive" are explained. 8.3.4.1 TriggerReady This event signals whether the camera is able to process incoming trigger signals or not. Trigger Exposure texposure(n) treadout(n) Readout TriggerReady texposure(n+1) treadout(n+1) tnotready 8.3.4.
8.3.4.3 TriggerOverlapped This signal is active, as long as the sensor is exposed and read out at the same time. which means the camera is operated overlapped. Trigger Exposure texposure(n) texposure(n+1) treadout(n) Readout treadout(n+1) Trigger Overlapped Once a valid trigger signal occures not within a readout, the "TriggerOverlapped" signal changes to state low. 8.3.4.4 ReadoutActive While the sensor is read out, the camera signals this by means of "ReadoutActive".
8.4 Software 8.4.1 Baumer GAPI Baumer GAPI stands for Baumer Generic Application Programming Interface. With this API Baumer provides an interface for optimal integration and control of Baumer cameras. This software interface allows changing to other camera models. It provides interfaces to several programming languages, such as C, C++ and the .NET™ Framework on Windows®, as well as Mono on Linux® operating systems, which offers the use of other languages, such as e.g. C# or VB.NET. 8.4.
9. Camera Functionalities 9.1 Image Acquisition 9.1.1 Image Format A digital camera usually delivers image data in at least one format - the native resolution of the sensor. Baumer cameras are able to provide several image formats (depending on the type of camera). Compared with standard cameras, the image format on Baumer cameras not only includes resolution, but a set of predefined parameter.
9.1.2 Pixel Format On Baumer digital cameras the pixel format depends on the selected image format. 9.1.2.1 Definitions RAW: Raw data format. Here the data are stored without processing. Bayer: Raw data format of color sensors. Color filters are placed on these sensors in a checkerboard pattern, generally in a 50% green, 25% red and 25% blue array. Mono: Monochrome. The color range of mono images consists of shades of a single color.
Pixel depth: In general, pixel depth defines the number of possible different values for each color channel. Mostly this will be 8 bit, which means 28 different "colors". For RGB or BGR these 8 bits per channel equal 24 bits overall. Two bytes are needed for transmitting more than 8 bits per pixel - even if the second byte is not completely filled with data. In order to save bandwidth, the packed formats were introduced to Baumer VisiLine IP cameras.
9.1.3 Exposure Time On exposure of the sensor, the inclination of photons produces a charge separation on the semiconductors of the pixels. This results in a voltage difference, which is used for signal extraction. Light Photon Charge Carrier Pixel Figure 14 ► Incidence of light causes charge separation on the semiconductors of the sensor. The signal strength is influenced by the incoming amount of photons. It can be increased by increasing the exposure time (texposure).
Camera Type PRNU/ DSNU 9.1.4 PRNU / DSNU Correction (FPN - Fixed Pattern Noise) CCD VLG-02M.I / VLG-02C.I □ VLG-12M.I / VLG-12C.I □ VLG-20M.I / VLG-20C.I □ CMOS VLG-22M.I / VLG-22C.I ■ VLG-40M.I / VLG-40C.I ■ CMOS sensors exhibit nonuniformities that are often called fixed pattern noise (FPN). However it is no noise but a fixed variation from pixel to pixel that can be corrected. The advantage of using this correction is a more homogeneous picture which may simplify the image analysis.
HDR 9.1.5 HDR (High Dynamic Range) Camera Type CCD VLG-02M.I / VLG-02C.I □ VLG-12M.I / VLG-12C.I □ VLG-20M.I / VLG-20C.I □ CMOS VLG-22M.I / VLG-22C.I ■ VLG-40M.I / VLG-40C.I ■ Beside the standard linear response the sensor supports a special high dynamic range mode (HDR) called piecewise linear response. With this mode illuminated pixels that reach a certain programmable voltage level will be clipped. Darker pixels that do not reach this threshold remain unchanged.
9.1.6 Look-Up-Table The Look-Up-Table (LUT) is employed on Baumer VisiLine IP monochrome and color cameras. It contains 212 (4096) values for the available levels. These values can be adjusted by the user. 9.1.7 Gamma Correction H With this feature, Baumer VisiLine IP cameras offer the possibility of compensating nonlinearity in the perception of light by the human eye.
9.1.8 Region of Interest With the "Region of Interest" (ROI) function it is possible to predefine a so-called Region of Interest (ROI) or Partial Scan. This ROI is an area of pixels of the sensor. On image acquisition, only the information of these pixels is sent to the PC. Therefore, not all lines of the sensor are read out, which decreases the readout time (treadout). This increases the frame rate. This function is employed, when only a region of the field of view is of interest.
9.1.9 Binning On digital cameras, you can find several operations for progressing sensitivity. One of them is the so-called "Binning". Here, the charge carriers of neighboring pixels are aggregated. Thus, the progression is greatly increased by the amount of binned pixels. By using this operation, the progression in sensitivity is coupled to a reduction in resolution. Baumer cameras support three types of Binning - vertical, horizontal and bidirectional.
9.1.10 Brightness Correction (Binning Correction) The aggregation of charge carriers may cause an overload. To prevent this, binning correction was introduced. Here, three binning modes need to be considered separately: Binninig Realization 1x2 1x2 binning is performed within the sensor, binning correction also takes place here. A possible overload is prevented by halving the exposure time. 2x1 2x1 binning takes place within the FPGA of the camera.
9.1.11 Flip Image The Flip Image function let you flip the captured images horizontal and/or vertical before they are transmitted from the camera. Notice Horizontal Vertical A defined ROI will also flipped. VLG-02M.I / VLG-02C.I ■ □ VLG-12M.I / VLG-12C.I ■ □ Camera Type VLG-20M.I / VLG-20C.I ■ □ VLG-22M.I / VLG-22C.I ■ ■ VLG-40M.I / VLG-40C.
9.2 Color Processing Baumer color cameras are balanced to a color temperature of 5000 K. Oversimplified, color processing is realized by 4 modules. r g b Figure 26 ► Color processing modules of Baumer color cameras. Camera Module r' g' b' Bayer Processor Y r'' g'' b'' Color Transfor mation RGB White balance The color signals r (red), g (green) and b (blue) of the sensor are amplified in total and digitized within the camera module.
9.3.2 One Push White Balance Here, the three color spectrums are balanced to a single white point. The correction factors of the color gains are determined by the camera (one time). non-adjusted histogramm histogramm after „one push“ white balance ◄ Figure 28 Examples of histogramms for a non-adjusted image and for an image after "one push" white balance. 9.4 Analog Controls 9.4.
9.4.2 Gain In industrial environments motion blur is unacceptable. Due to this fact exposure times are limited. However, this causes low output signals from the camera and results in dark images. To solve this issue, the signals can be amplified by a user-defined gain factor within the camera. This gain factor is adjustable. Notice Increasing the gain factor causes an increase of image noise. CCD Sensor Camera Type Gain factor [db] Monochrome VLG-02M.I 0...26 VLG-12M.I 0...26 VLG-20M.I 0...
9.5 Pixel Correction 9.5.1 General information A certain probability for abnormal pixels - the so-called defect pixels - applies to the sensors of all manufacturers. The charge quantity on these pixels is not linear-dependent on the exposure time. The occurrence of these defect pixels is unavoidable and intrinsic to the manufacturing and aging process of the sensors. The operation of the camera is not affected by these pixels.
9.5.2 Correction Algorithm On cameras of the Baumer VisiLine IP series, the problem of defect pixels is solved as follows: ▪▪ Possible defect pixels are identified during the production process of the camera. ▪▪ The coordinates of these pixels are stored in the factory settings of the camera. ▪▪ Once the sensor readout is completed, correction takes place: ▪▪ Before any other processing, the values of the neighboring pixels on the left and the right side of the defect pixels, will be read out.
9.6 Process Interface 9.6.1 Digital IOs 9.6.1.1 User Definable Inputs The wiring of these input connectors is left to the user. Sole exception is the compliance with predetermined high and low levels (0 .. 4,5V low, 11 .. 30V high). The defined signals will have no direct effect, but can be analyzed and processed on the software side and used for controlling the camera. The employment of a so called "IO matrix" offers the possibility of selecting the signal and the state to be processed.
9.6.1.2 Configurable Outputs With this feature, Baumer offers the possibility of wiring the output connectors to internal signals, which are controlled on the software side.
9.6.3 Trigger U Trigger signals are used to synchronize the camera exposure and a machine cycle or, in case of a software trigger, to take images at predefined time intervals. 30V 11V Trigger (valid) A high 4.5V low 0 Exposure t ▲ Figure 33 Trigger signal, valid for Baumer cameras. B Readout C Time Different trigger sources can be used here. able logic others c on trol er lectric se m pho t or ns oe program 9.6.
9.6.5 Debouncer The basic idea behind this feature was to seperate interfering signals (short peaks) from valid square wave signals, which can be important in industrial environments. Debouncing means that invalid signals are filtered out, and signals lasting longer than a user-defined testing time tDebounceHigh will be recognized, and routed to the camera to induce a trigger.
9.6.7 Timers Timers were introduced for advanced control of internal camera signals. For example the employment of a timer allows you to control the flash signal in that way, that the illumination does not start synchronized to the sensor exposure but a predefined interval earlier.
9.7 Sequencer 9.7.1 General Information A sequencer is used for the automated control of series of images using different sets of parameters. A A m B B C ◄ Figure 38 Flow chart of sequencer. m - number of loop passes n - number of set repetitions o - number of sets of parameters z - number of frames per trigger o C z The figure above displays the fundamental structure of the sequencer module. A sequence (o) is defined as a complete pass through all sets of parameters.
9.7.
9.7.3.2 Sequencer Controlled by Machine Steps (trigger) C C Sequencer Start B B A Figure 41 ► Example for a half-automated sequencer. A Trigger The figure above shows an example for a half-automated sequencer with three sets of parameters (A,B and C) from the previous example. The frame counter (z) is set to 2. This means the camera records two pictures after an incoming trigger signal. 9.7.
9.7.5 Double Shutter This feature offers the possibility of capturing two images in a very short interval. Depending on the application, this is performed in conjunction with a flash unit. Thereby the first exposure time (texposure) is arbitrary and accompanied by the first flash. The second exposure time must be equal to, or longer than the readout time (treadout) of the sensor. Thus the pixels of the sensor are recepitve again shortly after the first exposure.
9.9 User Sets Four user sets (0-3) are available for the Baumer cameras of the VisiLine IP series. User set 0 is the default set and contains the factory settings. User sets 1 to 3 are user-specific and can contain any user definable parameters. These user sets are stored within the camera and can be loaded, saved and transferred to other cameras of the VisiLine IP series.
10. Interface Functionalities 10.1 Device Information This Gigabit Ethernet-specific information on the device is part of the Discovery-Acknowledge of the camera. Included information: ▪▪ MAC address ▪▪ Current IP configuration (persistent IP / DHCP / LLA) ▪▪ Current IP parameters (IP address, subnet mask, gateway) ▪▪ Manufacturer's name ▪▪ Manufacturer-specific information ▪▪ Device version ▪▪ Serial number ▪▪ User-defined name (user programmable string) 10.
10.3 Packet Size and Maximum Transmission Unit (MTU) Network packets can be of different sizes. The size depends on the network components employed. When using GigE Vision®- compliant devices, it is generally recommended to use larger packets. On the one hand the overhead per packet is smaller, on the other hand larger packets cause less CPU load. The packet size of UDP packets can differ from 576 Bytes up to the MTU.
10.4.1 Example 1: Multi Camera Operation – Minimal IPG Setting the IPG to minimum means every image is transfered at maximum speed. Even by using a frame rate of 1 fps this results in full load on the network. Such "bursts" can lead to an overload of several network components and a loss of packets. This can occur, especially when using several cameras. In the case of two cameras sending images at the same time, this would theoretically occur at a transfer rate of 2 Gbits/sec.
10.5 Transmission Delay Another approach for packet sorting in multi-camera operation is the so-called Transmission Delay. Due to the fact, that the currently recorded image is stored within the camera and its transmission starts with a predefined delay, complete images can be transmitted to the PC at once. The following figure should serve as an example: Figure 48 ► Principle of the transmission delay.
10.5.2 Configuration Example For the three employed cameras the following data are known: Camera Model Sensor Pixel Format Resulting Readout Exposure Transfer Resolution (Pixel Depth) Data Volume Time Time Time (GigE) [Pixel] [bit] [bit] [msec] [msec] [msec] VLG-12M.I 1288 x 960 8 9891840 23.8 32 ≈ 9.2 VLG-20M.I 1624 x 1228 8 15954176 37 32 ≈ 14.9 VLG-02M.I 8 2571520 6.4 32 ≈ 2.
In general, the transmission delay is calculated as: n t TransmissionDelay( Camera n ) = t exp osure( Camera 1) + t readout ( Camera 1) − t exp osure( Camera n ) + ∑ t transferGigE( Camera n 1) n≥3 Therewith for the example, the transmission delays of camera 2 and 3 are calculated as follows: tTransmissionDelay(Camera 2) = texposure(Camera 1) + treadout(Camera 1) - texposure(Camera 2) tTransmissionDelay(Camera 3) = texposure(Camera 1) + treadout(Camera 1) - texposure(Camera 3) + ttransferGige(Camera 2)
10.6 Multicast Multicasting offers the possibility to send data packets to more than one destination address – without multiplying bandwidth between camera and Multicast device (e.g. Router or Switch). The data is sent out to an intelligent network node, an IGMP (Internet Group Management Protocol) capable Switch or Router and distributed to the receiver group with the specific address range.
Internet Protocol: 10.7 IP Configuration On Baumer cameras IP v4 is employed. 10.7.1 Persistent IP A persistent IP adress is assigned permanently. Its validity is unlimited. Notice Please ensure a valid combination of IP address and subnet mask. IP range: Subnet mask: 0.0.0.0 – 127.255.255.255 Figure 52 ▲ Connection pathway for Baumer Gigabit Ethernet cameras: The device connects step by step via the three descr bed mechanisms. 255.0.0.0 128.0.0.0 – 191.255.255.255 255.255.0.0 192.0.0.0 – 223.255.
▪▪ DHCP Request Once the client has received this DHCPOFFER, the transaction needs to be confirmed. For this purpose the client sends a so called DHCPREQUEST broadcast to the network. This message contains the IP address of the offering DHCP server and informs all other possible DHCPservers that the client has obtained all the necessary information, and there is therefore no need to issue IP information to the client.
10.8 Packet Resend Due to the fact, that the GigE Vision® standard stipulates using a UDP - a stateless user datagram protocol - for data transfer, a mechanism for saving the "lost" data needs to be employed. Here, a resend request is initiated if one or more packets are damaged during transfer and - due to an incorrect checksum - rejected afterwards. On this topic one must distinguish between three cases: 10.8.
◄ Figure 59 Resending of lost packets at the end of the data stream. In our example, packets from no. 3 to no. 5 are lost. This fault is detected after the predefined time has elapsed and the resend request (A) is triggered. The camera then resends packets no. 3 to no. 5 (B) to complete the image transfer. 10.8.
10.9 Message Channel The asynchronous message channel is described in the GigE Vision® standard and offers the possibility of event signaling. There is a timestamp (64 bits) for each announced event, which contains the accurate time the event occurred. Each event can be activated and deactivated separately. 10.9.
10.10 Action Command / Trigger over Ethernet The basic idea behind this feature was to achieve a simultaneous trigger for multiple cameras. Therefore a broadcast ethernet packet was implemented. This packet can be used to induce a trigger as well as other actions. Due to the fact that different network components feature different latencies and jitters, the trigger over the Ethernet is not as synchronous as a hardware trigger.
11. Start-Stop-Behaviour 11.1 Start / Stop / Abort Acquisition (Camera) Once the image acquisition is started, three steps are processed within the camera: ▪▪ Determination of the current set of image parameters ▪▪ Exposure of the sensor ▪▪ Readout of the sensor. Afterwards a repetition of this process takes place until the camera is stopped. Stopping the acquisition means that the process mentioned above is aborted.
12. Cleaning Cover glass Notice The sensor is mounted dust-proof. Remove of the cover glass for cleaning is not necessary. Avoid cleaning the cover glass of the sensor if possible. To prevent dust, follow the instructions under "Install lens". If you must clean it, use compressed air or a soft, lint free cloth dampened with a small quantity of pure alcohol. Housing Caution! Volatile solvents for cleaning. Volatile solvents damage the surface of the camera.
14. Disposal Dispose of outdated products with electrical or electronic circuits, not in the normal domestic waste, but rather according to your national law and the directives 2002/96/EC and 2006/66/EC for recycling within the competent collectors. Through the proper disposal of obsolete equipment will help to save valuable resources and prevent possible adverse effects on human health and the environment.
17. Conformity Baumer VisiLine IP cameras comply with: ▪▪ CE, ▪▪ FCC Part 15 Class B, ▪▪ RoHS 17.1 CE We declare, under our sole responsibility, that the previously described Baumer cameras conform with the directives of the CE. 17.2 FCC – Class B Device This equipment has been tested and found to comply with the limits for a Class B digital device, pursuant to part 15 of the FCC Rules. These limits are designed to provide reasonable protection against harmful interference in a residential environment.
Subject to change without notice. Printed in Germany. Technical data has been fully checked, but accuracy of printed matter not guaranteed. Baumer Optronic GmbH Baumer Optronic GmbH Badstrasse 30 DE-01454 Radeberg, Germany Phone +49 (0)3528 4386 0 · Fax +49 (0)3528 4386 86 sales@baumeroptronic.com · www.baumer.com DE-01454 Radeberg, Germany Phone +49 (0)3528 4386 0 · Fax +49 (0)3528 4386 86 sales@baumeroptronic.com · www.baumer.
