Describes the architecture of a hierarchical motion estimation processor, with respect to the MPEG-2 encoding standard. This processor can also be used in HDTV applications. The motion estimation processing is in 2 st...
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Describes the architecture of a hierarchical motion estimation processor, with respect to the MPEG-2 encoding standard. This processor can also be used in HDTV applications. The motion estimation processing is in 2 steps: first full-pixel then half-pixel. Several modes are possible, depending on the image types (I, P or B-MPEG terminology, frame based or field based). A decision is taken in this processor to choose the best mode. The architecture is based on a RISC controller, external DRAMs to store anchor frames and specific hardware for processing the distortions. The architecture was chosen to achieve high performance, programmability and high memory bandwidth.
Image quality assessment plays an important role to the 3G network QoE/QoS planners. A great deal of effort has been made in recent years to develop objective image quality metrics that correlate with perceived qualit...
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Image quality assessment plays an important role to the 3G network QoE/QoS planners. A great deal of effort has been made in recent years to develop objective image quality metrics that correlate with perceived quality measurement. Unfortunately, there is a lack of non-simulation image material to optimize the algorithms and the parameter settings. In this paper, we suggest a method to capture the frame of video phone on Dtivy™ A2000+H platform. With these frames, the objective image quality assessment algorithms could be improved so that they are used more targeted.
In modern embedded systems, the C2RTL (high-level synthesis) technology helps the designer to greatly reduce time-to-market, while satisfying the performance and cost constraints. To attack the performance challenges ...
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ISBN:
(纸本)9781467307703
In modern embedded systems, the C2RTL (high-level synthesis) technology helps the designer to greatly reduce time-to-market, while satisfying the performance and cost constraints. To attack the performance challenges in complex designs, we propose a FIFO-connected hierarchical approach to replace the traditional flatten one in stream applications. Furthermore, we develop an analytical algorithm to find the optimal FIFO capacity to connect multiple modules efficiently. Finally, we prove the advantages of the proposed method and the feasibility of our algorithm in seven real applications. Experimental results show that the hierarchical approach can have an up to 10.43 times speedup compared to the flatten design, while our analytical FIFO sizing algorithm shrinks design time from hours to seconds with the same accuracy compared to the simulation based approach.
This paper proposes an image compression approach, in which we incorporate primal sketch based learning into the mainstream image compression framework. The key idea of our approach is to use primal sketch information...
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This paper proposes an image compression approach, in which we incorporate primal sketch based learning into the mainstream image compression framework. The key idea of our approach is to use primal sketch information to enhance the quality of distorted images. With this method, we only encode the down-sampled image and use the primal sketch based learning to recover the high frequency information which has been removed by down-sampling. Experimental results demonstrate that our scheme achieves better objective visual quality as well as subjective quality compared with JPEG2000 at the same bit-rates.
This paper presents an authentication scheme for a JPEG 2000 image codestream, which is obtained by using JPEG 2000 Interactive Protocol (JPIP). JPIP allows a client to request a JPEG 2000 image that has a different r...
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This paper presents an authentication scheme for a JPEG 2000 image codestream, which is obtained by using JPEG 2000 Interactive Protocol (JPIP). JPIP allows a client to request a JPEG 2000 image that has a different representation from the original image. The client-requested image codestream is a portion of the original JPEG 2000 codestream and its structure differs for each client request. To verify the authenticity of the image requested by the client, a scalable verification mechanism is required. Hence, we propose a new scalable authentication scheme using an aggregate signature. The proposed scheme allows the scalable generation of digital signatures for any client-requested image. Simulation results show the effectiveness of the proposed scheme.
System-on-chip market relies on implementing multimedia products as embedded software modules on re-usable architecture platforms. The efficient implementation of the Jpeg2000 encoder engine is still challenging HW an...
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System-on-chip market relies on implementing multimedia products as embedded software modules on re-usable architecture platforms. The efficient implementation of the Jpeg2000 encoder engine is still challenging HW and SW developers with its highly complex computational kernel. While several hardwired Jpeg2000 enconding modules exist, the efficient programming of Jpeg2000 on re-usable embedded high-performance cores is still an open issue. We performed an exhaustive analysis of the attainable execution speedup when specialized SW is run on different architectures built upon a multimedia-oriented VLIW processor core, demonstrating that the compression effort can be reduced by more than 50% if a SIMD-extended architecture is adopted, and by 80% when the code is optimized for a multi-core architecture.
A novel algorithm is introduced that can detect the presence of interpolation in images prior to compression as well as estimate the interpolation factor. The interpolation detection algorithm exploits a periodicity i...
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A novel algorithm is introduced that can detect the presence of interpolation in images prior to compression as well as estimate the interpolation factor. The interpolation detection algorithm exploits a periodicity in the second derivative signal of interpolated images. The algorithm performs well for a wide variety of interpolation factors, both integer factors and non-integer factors. The algorithm performance is noted with respect to a digital camera's "digital zoom" feature. Overall the algorithm has demonstrated robust results and might prove to be useful for situations where an original resolution of the image determines the action of an image processing chain.
A family safety monitoring system is designed, which integrated function of telephone alarm, remote control by network, and video linkage. Host alarm system, controlled by MCU, collects data wirelessly from sensors, a...
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A family safety monitoring system is designed, which integrated function of telephone alarm, remote control by network, and video linkage. Host alarm system, controlled by MCU, collects data wirelessly from sensors, and makes remote alarm by DTMF. The video processing and transmitting system, with a DSP chip of TMS320F2812 as the core processor, transmits the video data by means of Bluetooth indoors, and by Ethernet in the residential district, so that remote control through Internet can be implemented.
Since the invention of the camera, photos have been used to document reality and to supply proof of events. Yet today it is easy to fabricate realistic images depicting events that never happened. Thus, dozens of pape...
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ISBN:
(纸本)9781509008254
Since the invention of the camera, photos have been used to document reality and to supply proof of events. Yet today it is easy to fabricate realistic images depicting events that never happened. Thus, dozens of papers strive to develop methods for authenticating images. While some commercial cameras already attach digital signatures to photographs, the images often undergo subsequent transformations (cropping, rotation, compression, and so forth), which do not detract from their authenticity, but do change the image data and thus invalidate the signature. Existing methods address this by signing derived image properties that are invariant to some set of transformations. However, these are limited in the supported transformations, and often offer weak security guarantees. We present PhotoProof, a novel approach to image authentication based on cryptographic proofs. It can be configured, according to application requirements, to allow any permissible set of (efficiently computable) transformations. Starting with a signed image, our scheme attaches, to each legitimately derived image, a succinct proof of computational integrity attesting that the transformation was permissible. Anyone can verify these proofs, and generate updated proofs when applying further permissible transformations. Moreover, the proofs are zero-knowledge so that, for example, an authenticated cropped image reveals nothing about the cropped-out regions. PhotoProof is based on Proof-Carrying Data (PCD), a cryptographic primitive for secure execution of distributed computations. We describe the new construction, prove its security, and demonstrate a working prototype supporting a variety of permissible transformations.
A new neural network data compression method is presented. This work extends the use of 2-layer neural networks to multi-layer networks. Results show the performance superiority of multi-layer neural networks compared...
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A new neural network data compression method is presented. This work extends the use of 2-layer neural networks to multi-layer networks. Results show the performance superiority of multi-layer neural networks compared to that of the 2-layer one especially at high compression ratios. To overcome the long training time required for multi-layered networks, a recently developed training algorithm has been used. A modified feedback error is proposed to further reduce the training time and to enhance the image quality. Also, a redistribution of the gray levels in the training phase is proposed to make the minimization of the mean square error more related to the human visual system.
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