a novel study on data rate by the video transmission for ... filea novel study on data rate by the...

A Novel Study on Data Rate by the Video Transmission for Teleoperated Road

VehiclesTito Tang, Frederic Chucholowski, Min Yan and Prof. Dr. Markus

Lienkamp

9th International Conference on Intelligent Unmanned Systems25.-27. September 2013

ConclusionDiscussionResultsExperimental SetupApproachIntroduction

Driverless vehicle delivery

� Car sharing� Delivery to front door� Distribution of vehicles� Driving vehicles to charging stations

� Private electric vehicles� No private parking lot� No private charging station� Driving vehicles to charging stations� Delivery of charged vehicle to front door

ICIUS 2013 225.-27. September 2013


Autonomous vs.teleoperated vehicles

� Autonomous vehicles� Scenarios with low complexity� Highways

� Teleoperated vehicles� Urban traffic� Red lights� Pedestrians



System setup



Transmission

� Cellular networks� UMTS-HSPA: nominal upload rate: 11 Mbit/s� LTE: max. nominal upload rate: 75 Mbit/s

� Raw video� Gray-scale video� 640 x 480 pixels� 25 frames per second


58.6 Mbit/s


Video CODEC (enCOding, DECoding)

� MPEG-2� MPEG-4� H.264/AVC (MPEG-4 Part10)



Problem Statement

� A high bandwidth is required for a smooth display of video streamsused in teleoperated system

� Current available bandwidth through cellular network is limited

� A novel study on methods to reduce the data rate for the videodata transmission



Canny edge detection algorithm



LaPlace edge detection algorithm



Foveated imaging technique



H.264/AVC Video Compression

Goals:� Equally distributed and low datarate� Minimum latency

Implementation:� x264 open source video encoding library� Only I- and P-frames� No B-frames (no reference to following frames)

� => No additional encoding delay

� Baseline profile� „veryfast“ and „zerolatency“ encoder presets� „intra refresh“ feature distributes I-frames



„Intra refresh“ feature avoids data rate bursts



Cameras� 8 Cameras, each with a 640x480

resolution

� 25 Frames per second in grey-scale

� Front field of view of approx. 240 degrees



Scenarios


Scenario 1: homogeneous without other

vehicles

Scenario 2: more complex, with vehicles

and pedestrians


Results

� CPU Intel© Core (TM) i5, 2.4 GHz M520 � Windows XP operating system� 2.0 GB RAM


Table 1 Average Time for Processing Each Frame

Scenario 1 Scenario 2 H.264/AVC 10.17 [ms] 11.46 [ms] Canny-Algorithm 27.27 [ms] 27.06 [ms] LaPlace-Algorithm 14.08 [ms] 14.20 [ms] Foveated-Imaging 09.00 [ms] 10.37 [ms]


Comparison in data size



Discussion

� Edge-detection algorithms� Reduce amount of information� Increase in data rate because of sharp corners in frame

� Foveated-Image-Technique� Slight decrease in data rate� Scenario 1: reduction of ~19%� Scenario 2: reduction of ~17%



Conclusion

� Approaches to reduce data rate for data transmission� Canny-Algorithm� Laplace-Algorithm� Foveated-Imaging-Technique

� Setup of x264 H.264/AVC video encoder� Efficient and robust� Minimum encoding latency

� Results show that edge-detection techniques do not provide a reduction, but the Foveated-Imaging-Technique does



Further research

� Determination of area of interest for Foveated-Imaging-Technique� Head-tracking� Eye-tracking

� Possible further reduction using upcoming High Efficiency Video Codec (HEVC or H.265)


Thank you for your attention


A Novel Study on Data Rate by the Video Transmission for Teleoperated Road

VehiclesTito Tang, Frederic Chucholowski, Min Yan and Prof. Dr. Markus

Lienkamp

9th International Conference on Intelligent Unmanned Systems25.-27. September 2013

a novel study on data rate by the video transmission for ... filea novel study on data rate by the...

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