Desarrollo Eléctrico Septiembre 2007 A System for Night Video Acquisition and Synchronisation...

Desarrollo Eléctrico Septiembre 2007

A System for Night Video Acquisition and SynchronisationFrancesc DorcaCentro Técnico de SEAT


Assessment of frontlighting systems

Classical dynamic test

Drawbacks of the classical method

The idea behind the new tool

How to use the tool

Advantages of the new tool

SCHEDULE


During the development of a new headlamp system, the main goals of tests are to guarantee:

Fulfilment of all legal prescriptionsGood quality Good reliability

Performance assessment

Assessment of FL Systems


Important headlamp’s performance factors are:

Overall light flux, Near field lighting, Light intensity, Lighting on the own track,Homogeneity, Lighting on the opposite track,Light colour, Area covered by a selected Isolux line,Glare avoidance, Scattered light,Width of the LB, . . . Range reached by the LB,



Therefore it is nearly impossible to evaluate and summarise the quality level of a lighting system with a single number.

Nevertheless it is usually quite simple to compare two light sources and decide which one is better.



We want to ensure that the headlamps of a new model are better than:

• these of the previous model (Continuous performance improvement)

• the competitor’s headlamps (Benchmarking)



To evaluate the performance of a lighting system, two different tests are needed:

Static evaluation on the light screen

Dynamic evaluation on a test track



With the growth of AFS systems, dynamic tests become more and more important.



The cars to be tested are driven in a test track by a group of experts.

At the end of each driving cycle, the experts fill a single evaluation form with their impressions.

Classical dynamic test


The evaluation can be strongly subjective, depending on people’s mood.



The evaluation forms are the only existing record of the dynamic test.



If some specific aspect of the light distribution is criticised, the only way to verify it is to repeat the test.



It is nearly impossible to compare two frontlighting systems, if they were not tested on the same day.



To keep a graphical memory of the dynamic test, the first idea would be to record a video sequence.



We can not expect that two different drives in the same track were made exactly the same way.

If we view two different sequences at the same time, these are not synchronised.

We must find a way to synchronise any pair of videos.

To synchronise the sequences we could use synchronisation marks at specific points of the test track.



Preparing the test

Aim the headlamps of the cars Adjust the options of the camera menuScrew the camera on the holderFix the holder on the windscreenAdjust the pitch, yaw and roll anglesPut the synchronisation marks on the test track

How to use the tool

A

B


Recording the sequences

Record the video sequence during the driveDrive the first test car trying to keep a slow constant

speed Prepare next test car . . .Repeat until the last car is driven

How to use the tool


Acquiring the video sequences

Start the VideoSync applicationOn the Main Control window, select the icon of the

video cameraA new Cut window appearsCut the different sequences one-by-one

How to use the tool


Annotate the sequences

On the main control window, select the glasses icon Input relevant test data (date, time, driver, car model, headlamp…test track name)These data will be integrated into a database of video sequences

How to use the tool


Synchronise the videos

On the Annotation window, select the clock iconSynchronise the sequence using the sync marks on the

track

* There is a reference sequence for each test track on the DB

How to use the tool


Search, select and view video sequences

Search any couple of videos on the database using an SQL-querySelect the videos to be viewed among the files retrieved.It is possible to launch the VideoSync directly, selecting the screen icon on the Search window

How to use the tool


View a couple of video sequences

You can also select the screen icon on the Main window to launch the SyncPlayer

How to use the tool


The new tool brings us following advantages:

A video sequence of each test is stored on the PC

All test-relevant data are integrated into a database

The review of any dynamic test performed is always possible. No matter how old or new a sequence is.

The new software tool allows a more objective system evaluation

We can view any 2 sequences from the DB recorded at the same test track perfectly synchronised

Advantages of the new tool


¡ Thank you for your Attention !

Date post:	24-Dec-2015
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Desarrollo Eléctrico Septiembre 2007 A System for Night Video Acquisition and Synchronisation...

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