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A FPGA Design of Bit-plane Coding for JPEG 2000
JPEG 2000系数位平面编码的FPGA设计*

YANG Ke,LIU Ming-ye,

计算机应用研究 , 2005,
Abstract: FPGA implementation of the bit-plane coding in JPEG 2000 standard is studied in the paper. A architecture suitable for ASIC implementation is proposed ,which greatly speeds up the coding process and achieves higher hardware utilization, solve the problem how to read and write the coefficient state words in the RAMS, and decreases the frequency of the system to visit the coefficient state words in the RAMS. In this paper, cleanup pass works concurrently with magnitude refinement pass, which reduces the processing time by more than 30% compared with the conventional design. The design is simulated and verified on FPGA.
JPEG2000自适应算术编码器FPGA设计  [PDF]
北京理工大学学报 , 2005,
Abstract: 研究JPEG2000标准中自适应算术编码器的硬件实现问题,提出一种适合ASIC实现的并行结构,并在FPGA上对其进行了仿真验证.该设计使用VHDL语言在RTL级描述;并以XILINXXC2V8000-5FF1152为基础,在ISE5.2下完成综合及后仿真.在整个JPEG2000设计中,最高工作时钟66MHz,自适应算术编码器处理速度可达到0.25bit/cycle.
Fast FPGA Implementation of EBCOT block in JPEG2000 Standard
Anass Mansouri,Ali Ahaitouf,Farid Abdi
International Journal of Computer Science Issues , 2011,
Abstract: Embedded block coding with optimized truncation (EBCOT) is an important feature of the latest digital still-image compression standard, JPEG2000; however, it consumes more than 50% of the computation time in the compression process. In this paper, we propose a new high speed VLSI implementation of the EBCOT algorithm. The main concept of the proposed architecture is based on parallel access to memories, and uses an efficient design of the context generator block. The proposed architecture is described in VHDL language, verified by simulation and successfully implemented in a Cyclone II and Stratix III FPGA. It provides a major reduction in memory access requirements, as well as a net increase of the processing speed as shown by the simulations.
Strict Authentication Watermarking with JPEG Compression (SAW-JPEG) for Medical Images  [PDF]
Jasni Mohamad Zain
Computer Science , 2011,
Abstract: This paper proposes a strict authentication watermarking for medical images. In this scheme, we define region of interest (ROI) by taking the smallest rectangle around an image. The watermark is generated from hashing the area of interest. The embedding region is considered to be outside the region of interest as to preserve the area from distortion as a result from watermarking. The strict authentication watermarking is robust to some degree of JPEG compression (SAW-JPEG). JPEG compression will be reviewed. To embed a watermark in the spatial domain, we have to make sure that the embedded watermark will survive JPEG quantization process. The watermarking scheme, including data embedding, extracting and verifying procedure were presented. Experimental results showed that such a scheme could embed and extract the watermark at a high compression rate. The watermark is robust to a high compression rate up to 90.6%. The JPEG image quality threshold is 60 for the least significant bit embedding. The image quality threshold is increased to 61 for 2nd and 3rd LSB manipulations.
Watermarking FPGA Bitfile for Intellectual Property Protection
J. Zhang,Y. Lin,Q. Wu,W. Che
Radioengineering , 2012,
Abstract: Intellectual property protection (IPP) of hardware designs is the most important requirement for many Field Programmable Gate Array (FPGA) intellectual property (IP) vendors. Digital watermarking has become an innovative technology for IPP in recent years. Existing watermarking techniques have successfully embedded watermark into IP cores. However, many of these techniques share two specific weaknesses: 1) They have extra overhead, and are likely to degrade performance of design; 2) vulnerability to removing attacks. We propose a novel watermarking technique to watermark FPGA bitfile for addressing these weaknesses. Experimental results and analysis show that the proposed technique incurs zero overhead and it is robust against removing attacks.
Dual watermarking algorithm for copyright protection of digital images

WANG Ting,LIU Jiang,WANG Xi-chang,
王婷 刘江

计算机应用 , 2007,
Abstract: A dual watermarking algorithm that accepted JPEG compression was presented.The original image was first segmented into blocks based on the texture property,and different embedding intensities were used to embed the watermarking into the Discrete Cosine Transform(DCT) domain of the original image to indicate ownership of the image.And then the invisible watermarking was embedded into the high frequence part to verify ownership of the image.The experiment shows that the proposed dual watermarking system can indicate and verify the ownership.
Improved DWT Based Watermarking Using JPEG-YCbCr  [PDF]
Mehdi Khalili,David Asatryan
Computer Science , 2012,
Abstract: In this paper a blind, Secure, imperceptible and robust watermarking algorithm based on wavelet transform domain is proposed in which for more security, the watermark W is converted to a sequence and then a random binary sequence R of size n is adopted to encrypt the watermark, where n is the size of the watermark image. Afterwards, the encrypted watermark sequence W1 is generated by executing exclusive-OR operation on W and R. This generated watermark embeds into low frequency selected coefficients of Y channel wavelet decomposition of JPEG-YCbCr using LSB insertion technique. The experimental results show that the proposed algorithm increases the security and imperceptibility of watermark and has better robustness against wavelet compression and cropping attacks compared to the earlier work in [1].
An Efficient Pipeline Design of JPEG2000 Encoder with Low Memory

Mei Kui-zhi,Zheng Nan-ning,Liu Yue-hu,Yao Ji,Huang Yu,Wang Yong,

电子与信息学报 , 2006,
Abstract: An efficient JPEG2000 encoder is proposed and implemented with high pipeline and low memory architecture. Dual buffers to save the wavelet coefficients, pre-rate allocation and byte expression for Rate-Distortion (RD) slope are used to reduce on-chip memory size. Pipeline and parallel architecture is used in Discrete Wavelet Transform (DWT), Bit-Plane Encoder (BPE) and Arithmetic Encoder (AE) to increase the part circuit’s encoding speed, searching the truncated RD slope in byte address space increases the packet formatting speed of Tier2. Problems met in system implementation such as clock distribution, SDRAM control of frame buffer and chrominance-transformation are also designed with optimization. The encoder is verified on FPGA platform. Performance of the encoder is as follows: the size of tile is up to 256×256 with code block in size of 32×32, input sampling rate is up to 45Msamples/s when Tier1 is working at the clock of 100 MHz, difference of the PSNR of images compressed by the proposed encoder and JASPER is less than 0.5dB at the rate of 0.4 bit per sample (bps). Equivalent gates synthesized are about 109k and on-chip RAM is 862kb.
Effects of JPEG Compression on Reading Optical Watermarking Embedded by Using Color-Difference Modulation  [PDF]
Kazutake Uehira, Hiroshi Unno
Journal of Computer and Communications (JCC) , 2018, DOI: 10.4236/jcc.2018.61006
In this paper, we evaluate the readability of optically written watermarking from an image compressed by JPEG. We previously proposed an optical watermarking technique that can protect the portrait rights of real objects. It produces a watermarking pattern in the illumination light by modulating color differences. The illumination light that contains such watermarking is pro-jected onto an object. An image of the object taken by a camera contains the same watermarking, which can be extracted by image processing. Therefore, this technique can protect the portrait rights of real objects. We conducted simulations of capturing an object image illuminated by watermarked light, compressing it by JPEG, and reading embedded information from the decoded image. The simulation results showed that the accuracy in reading out embedded information decreases when captured images are compressed. However, for medium-level or low compression rates 100% accuracy can be expected by using the error correction technique.
New semi-fragile watermarking for JPEG image authentication


计算机应用 , 2007,
Abstract: This paper presented a watermarking scheme for JPEG image authentication.The watermark was generated based on the relative sign and magnitudes of Discrete Cosine Transform(DCT) coefficients which were invariant due to an important property of JPEG compression.Combined with an effective method to include all the coefficients either explicit or implicit,the proposed algorithm improved its security level against malicious attacks in transform domain,without embedding more watermarking information in the original image.At the same time,an identification of false tampered blocks in the proposed authentication algorithm improved the accuracy of locating tampered areas.Analysis and experimental results are provided to demonstrate that the watermarked image possesses good perceptual transparence,and that the proposed algorithm takes JPEG compression as an acceptable manipulation.Meanwhile,it is sensitive to other malicious attacks and can locate the tampered areas.
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