Limits...
Distributed coding/decoding complexity in video sensor networks.

Cordeiro PJ, Assunção P - Sensors (Basel) (2012)

Bottom Line: Such gateways provide real-time transcoding functionalities for bandwidth adaptation and coding/decoding complexity distribution by transferring the most complex video encoding/decoding tasks to the transcoding gateway at the expense of a limited increase in bit rate.Then, a method to reduce the decoding complexity, suitable for system-on-chip implementation, is proposed to operate at the transcoding gateway whenever decoders with constrained resources are targeted.The results show that the proposed method achieves good performance and its inclusion into the VSN infrastructure provides an additional level of complexity control functionality.

View Article: PubMed Central - PubMed

Affiliation: Instituto Politécnico de Leiria/ESTG, Alto Vieiro, Leiria, Portugal. paulo.cordeiro@ipleiria.pt

ABSTRACT
Video Sensor Networks (VSNs) are recent communication infrastructures used to capture and transmit dense visual information from an application context. In such large scale environments which include video coding, transmission and display/storage, there are several open problems to overcome in practical implementations. This paper addresses the most relevant challenges posed by VSNs, namely stringent bandwidth usage and processing time/power constraints. In particular, the paper proposes a novel VSN architecture where large sets of visual sensors with embedded processors are used for compression and transmission of coded streams to gateways, which in turn transrate the incoming streams and adapt them to the variable complexity requirements of both the sensor encoders and end-user decoder terminals. Such gateways provide real-time transcoding functionalities for bandwidth adaptation and coding/decoding complexity distribution by transferring the most complex video encoding/decoding tasks to the transcoding gateway at the expense of a limited increase in bit rate. Then, a method to reduce the decoding complexity, suitable for system-on-chip implementation, is proposed to operate at the transcoding gateway whenever decoders with constrained resources are targeted. The results show that the proposed method achieves good performance and its inclusion into the VSN infrastructure provides an additional level of complexity control functionality.

No MeSH data available.


Related in: MedlinePlus

Rate-PSNR performance for different values of λC. (a) Container; (b) Foreman.
© Copyright Policy
Related In: Results  -  Collection

License
getmorefigures.php?uid=PMC3376628&req=5

f7-sensors-12-02693: Rate-PSNR performance for different values of λC. (a) Container; (b) Foreman.

Mentions: The efficiency of the proposed constrained coding method was experimentally evaluated in order to assess how decoding complexity can be reduced and how much quality drop is observed. Two sequences (Container and Foreman) with different types of motion were used in order to assess the influence of the video signal characteristics on the performance of the proposed method. The baseline mode of H.264/AVC was used as this is more appropriate to mobile devices. The experimental setup was defined according to the recommended simulation conditions for coding efficiency experiments [46,47]. As shown in Figure 7, the proposed method produces a small drop in PSNR for a wide range of bit rates, in comparison with normal H.264/AVC rate-distortion optimization.


Distributed coding/decoding complexity in video sensor networks.

Cordeiro PJ, Assunção P - Sensors (Basel) (2012)

Rate-PSNR performance for different values of λC. (a) Container; (b) Foreman.
© Copyright Policy
Related In: Results  -  Collection

License
Show All Figures
getmorefigures.php?uid=PMC3376628&req=5

f7-sensors-12-02693: Rate-PSNR performance for different values of λC. (a) Container; (b) Foreman.
Mentions: The efficiency of the proposed constrained coding method was experimentally evaluated in order to assess how decoding complexity can be reduced and how much quality drop is observed. Two sequences (Container and Foreman) with different types of motion were used in order to assess the influence of the video signal characteristics on the performance of the proposed method. The baseline mode of H.264/AVC was used as this is more appropriate to mobile devices. The experimental setup was defined according to the recommended simulation conditions for coding efficiency experiments [46,47]. As shown in Figure 7, the proposed method produces a small drop in PSNR for a wide range of bit rates, in comparison with normal H.264/AVC rate-distortion optimization.

Bottom Line: Such gateways provide real-time transcoding functionalities for bandwidth adaptation and coding/decoding complexity distribution by transferring the most complex video encoding/decoding tasks to the transcoding gateway at the expense of a limited increase in bit rate.Then, a method to reduce the decoding complexity, suitable for system-on-chip implementation, is proposed to operate at the transcoding gateway whenever decoders with constrained resources are targeted.The results show that the proposed method achieves good performance and its inclusion into the VSN infrastructure provides an additional level of complexity control functionality.

View Article: PubMed Central - PubMed

Affiliation: Instituto Politécnico de Leiria/ESTG, Alto Vieiro, Leiria, Portugal. paulo.cordeiro@ipleiria.pt

ABSTRACT
Video Sensor Networks (VSNs) are recent communication infrastructures used to capture and transmit dense visual information from an application context. In such large scale environments which include video coding, transmission and display/storage, there are several open problems to overcome in practical implementations. This paper addresses the most relevant challenges posed by VSNs, namely stringent bandwidth usage and processing time/power constraints. In particular, the paper proposes a novel VSN architecture where large sets of visual sensors with embedded processors are used for compression and transmission of coded streams to gateways, which in turn transrate the incoming streams and adapt them to the variable complexity requirements of both the sensor encoders and end-user decoder terminals. Such gateways provide real-time transcoding functionalities for bandwidth adaptation and coding/decoding complexity distribution by transferring the most complex video encoding/decoding tasks to the transcoding gateway at the expense of a limited increase in bit rate. Then, a method to reduce the decoding complexity, suitable for system-on-chip implementation, is proposed to operate at the transcoding gateway whenever decoders with constrained resources are targeted. The results show that the proposed method achieves good performance and its inclusion into the VSN infrastructure provides an additional level of complexity control functionality.

No MeSH data available.


Related in: MedlinePlus