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Article
Implementations Of 8x8 DCT And IDCT on Different FPGA Technologies Using the Modified Loeffler Algorithm

Author: N. H. Abbas
Journal: Journal of Engineering مجلة الهندسة ISSN: 17264073 25203339 Year: 2005 Volume: 11 Issue: 4 Pages: 707-714
Publisher: Baghdad University جامعة بغداد

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Abstract

In this paper the hardware implementations is investing of 8x8 Discrete Cosine Transform (DCT) and Inverse Discrete Cosine Transform (IDCT) on different Field Programmable Gate Array (FPGA) technologies using the modified Loeffler algorithm. The investigations involved simulations, and synthesis of Very High Speed Integrated Circuit Hardware Description Language (VHDL) code utilizing recent FPGA families of Xilinx, Altera, and Lucent. The paper achieving the most demanding real-time requirements of some standardized frame resolutions and rates. Synthesis results for 8-point DCT/IDCT implementations indicate operating frequencies of 50 MHz, 60 MHz, and 22 MHz for the investigated Xilinx, Altera and Lucent FPGA chips, respectively. These frequencies allow 2193 Source Input Format (SIF) and 100 High Definition Television (HDTV) frames to be processed by the Xilinx FPGA. The resulting frame processing rates for Lucent are 877 and 40 for SIF and HDTV, while for Altera they are 647 and 29, respectively. Results indicate that the investigated FPGA implementations would speed DCT based compression algorithms up to frame rates well above the real-time requirements of SIF, International Consulting Committee on Radio & Television (CCIR-TV) and HDTV frame formats.

في هذه المنشورة تم الاستقصاء عن البناء المادي لـ 8x8 تحويلة الجيب تمام المتقطعة (DCT) ومعكوسة تحويلة ألجيب تمام ألمتقطعة (DCT) في عدة تقنيات لترتيب بوابة برمجة المجال( (FPGAباستخدام خوارزمية Loeffler المحورة. الاستقصاء يتضمن التشبيه والتركيب لشفرة لغة وصف الكيان المادي ذات السرعة العالية جدا (VHDL) المستخدمة في ألآونة الاخيرة عن طريق عوائل ترتيب بوابة برمجة المجال (FPGA) من شركةLucent & Xilinx Altera . إن اغلب متطلبات الزمن الحقيقي (real-time) لبعض تصاميم الهياكل ومعدلاتها القياسي تم تحقيقها. نتائج ألتركيب لبناء 8 نقط تحويلة جتا المتقطعة (DCT) او معكوسها تبين انه ترددات العمل هي 50 ميغاهرتز و 22 ميغاهرتز، 60 ميغاهرتز و22 ميغاهرتز لقطع Lucent & , Altera , Xilinx ترتيب وابة المجال على التوالي. النتائج تبين انه استخدام الـ FPGA لبناء DCT & IDCT يسرع منه وكذلك الاقتراب يكون أكثر من تحقيق متطلبات الزمن الحقيقي لصيغة أدخال المصدر (SIF)، الجمعية الاستشارية الدولية للراديو والتلفزيون (CCIR-TV) والتلفزيون العالي التعريف (HDTV) من صيغ الهياكل.


Article
Digital Watermarking in Color Image Based On Joint Between DCT and DWT
العلامة المائية الرقمية في الصورة الملونة على أساس الربط بين DCT وDWT

Author: Jasim Mohammed Salih Ismail جاسم محمد صالح إسماعيل
Journal: Ibn Al-Haitham Journal For Pure And Applied Science مجلة ابن الهيثم للعلوم الصرفة والتطبيقية ISSN: 16094042/ 25213407 Year: 2017 Volume: 30 Issue: 1 Pages: 237-245
Publisher: Baghdad University جامعة بغداد

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Abstract

The massive distribution and development in the digital images field with friendly software, that leads to produce unauthorized use. Therefore the digital watermarking as image authentication has been developed for those issues. In this paper, we presented a method depending on the embedding stage and extraction stag. Our development is made by combining Discrete Wavelet Transform (DWT) with Discrete Cosine Transform (DCT) depending on the fact that combined the two transforms will reduce the drawbacks that appears during the recovered watermark or the watermarked image quality of each other, that results in effective rounding method, this is achieved by changing the wavelets coefficients of selected DWT sub bands (HL or HH), followed by applying DCT transform on the selected sub band's coefficients, this method focuses on the invisibility for the embedded watermark bits, and the quality for the watermarked image; furthermore it focuses on a subjective for the recovered watermark after extraction stage. The proposed method was evaluated by using simple image quality matrix illustrated in the results, and it was found that the proposed method provide good objective quality, the recovered watermark extracted successfully and the quality of recovered watermark are survived.

أن التطور الحاصل في مجال الصورة الرقمية مع توفر البرمجيات المختصة بمعالجة الصور وسهولة استعمالها جعل من عملية التزوير والتلاعب متاحاً للجميع. العلامة المائية الرقمية كانت من أهم الحلول لحل هذه المشكلة. تقدم هذه الورقة البحثية طريقة مقترحة تتضمن عملية ربط كلًّ من DCT وDWT في بيئة واحدة لغرض تضمين العلامة المائية داخل الصورة الملونة. ضمن هذه البيئة وذلك لغرض الحصول على أعلى جودة للصورة المضمنة للعلامة المائية ما بعد الإخفاء وكذلك لتجنب المشاكل التي قد تظهر نتيجة استعمال إحدى الطريقتين بشكل منفصل، من خلال التلاعب بقيم معاملات DWT ضمن نطاق الترددات الواطئة متبوعة بعملية تطبيق DCT خلال عملية التضمين، وتركز هذه الطريقة على عدم وجود تشوهات بعد تضمين العلامة المائية في الصورة الأصلية وعلى جودة الصورة النهائية بعد تضمين العلامة المائية فيها بالإضافة إلى التركيز على العلامة المائية المسترجعة بعد عملية الاستخراج. لقد تم تقييم الطريقة المقترحة من خلال استعمال بعض المعايير الرئيسة ضمن هذا المجال والتي تم تفصيلها في فقرة النتائج، أظهرت النتائج ان الطريقة المقترحة لها القدرة على المحافظة على جودة الصورة المضمنة والعلامة المائية المسترجعة، إذ ان جودة الصورة المضمنة كانت جيدة.


Article
Image Features Evaluation Using New Algorithm Proposed For Reducing Image Feature Number & Size Stored In Database

Author: Shahlaa T. Abdulwahab
Journal: Engineering and Technology Journal مجلة الهندسة والتكنولوجيا ISSN: 16816900 24120758 Year: 2011 Volume: 29 Issue: 6 Pages: 1176-1194
Publisher: University of Technology الجامعة التكنولوجية

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Abstract

This study proposes technique that capable of reducing image features size andnumber stored in the database. The proposed technique depends on the image contentof numerical values for the three basic colors (red, green and blue) and then stores it inthe database and to be used for image retrieval. This technique has been developedbased on recent image retrieval procedures that include Color Descriptor Matrix,YCbCr Color Space and Discrete Cosine Transform. Those procedures have beenapplied sequentially on the image and finally Kekre’s Transform has been applied inthe last stage of this technique to evaluate image features and reduce its stored size inthe database. The validity and accuracy of the proposed technique have beenevaluated through experiments by applying Kekre’s Transform on Color DescriptorMatrix instead of using Kekre’s Transform directly on the image in order to reduce itsfeature stored size. Another experiments have been tested and evaluated that includethe application of YCbCr Color Space on the Color Descriptor Matrix andfinally Kekre’s Transform to be executed and explore the image features size andcompare it with the previous stage. The effect of applying the Discrete CosineTransform on the YCbCr Color Space and finally the Kekre’s Transform on the imagefeatures size has been studied and compared with the previous step. It is concluded thatthe best reduction in image features size stored in the database can be obtained onlywhen Kekre’s Transform applied in the last step of the proposed technique withunchanged threshold based image retrieval ratios. Parametric study has been conductedto investigate the effect of applying the new algorithm on both isolated and mixedimage groups. Good precision ratios of 82% and 65% have been obtained for theisolated and mixed image groups respectively.


Article
Image Encryption using Resilient Boolean Function and DCT

Authors: Hussam A. Darweesh --- Ekbal H. Ali --- Azhar Malik
Journal: Engineering and Technology Journal مجلة الهندسة والتكنولوجيا ISSN: 16816900 24120758 Year: 2011 Volume: 29 Issue: 12 Pages: 2551-2563
Publisher: University of Technology الجامعة التكنولوجية

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Abstract

The information security is becoming more important in data storage and transmission, where images are widely used in it. The Stream cipher cryptosystems are extensively used for provide a reliable and efficient method of security. The new propose system image encryption investigated by encrypt the powerful frequency coefficients in DCT by used saturated best resilient Boolean function that constructed by Zhang's constructions that implement Maiorana-McFarland like constructions technique and its modifications. The simulation results of the proposal system calculate correlation test (Corr1) and PSNR1 to compare between original and encrypted image as parameter of robustness, and correlation test (Corr2) and PSNR2 as correlation parameter between original and decrypted image as parameter of quality in reconstruct image.


Article
English Capital Letters Recognition Depends On Computing The Seven Moments
تمییز الأحرف الأنكلیزیة الكبیرة بالأعتماد على حساب العزوم السبعة

Authors: Abdul Monem S. Rahma عبدالمنعم ابو طبیخ --- Ikhlas F.Nassir اخلاص ناصر
Journal: AL-MANSOUR JOURNAL مجلة المنصور ISSN: 18196489 Year: 2011 Issue: 16 Pages: 1-21
Publisher: Private Mansour college كلية المنصور الاهلية

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Abstract

There are many digital images for printed documentsand the research will continue to arrive to the bestalgorithm for identifying the English characters symbolsand those letters more frequently. There has been a greatarea for these researches. This research uses an imagethat contains single character each. The proposedrecognition process begins by converting that image intofrequency domain by applying discrete cosinetransform(DCT) , computing the seven moments for thisimage as a features for that character and then building adatabase which depends on these features for recognitiontask. The aim of this research is to prove that each capitalletter has been written with the same font and size but indifferent directions is also one of the English capital letterbecause it has the same seven moment’s values.

ھنالك الكثیر من الصور الرقمیة للوثائق المطبوعة والبحث مازال مستمراً للوصول الىافضل الخوارزمیات في التعرف على رموز الأحرف الأنكلیزیة التي ھي اكثر شیوعاً وقدكان ھنالك مساحة كبیرة لھا في ھذة البحوث. یستخدم ھذا البحث صورة تحوي حرفاًfrequency domain واحداً وطریقة التمییز المقترحة تبدأ بتحویل الصورة الىبعدھا تحسب العزوم السبعھ لذلك الحرف لأبراز (DCT) وذلك بتطبیق قانون التحویلمزایا الحرف ثم بناء قاعدة بیانات تعتمد على ھذه المزایا لعملیة التمییز.الھدف من البحثھو برھنة كل حرف كبیر كتب بنفس الخط والحجم لكن بأتجاھات مختلفھ ھو واحد منالحروف الأنكلیزیة الكبیرة أیضا وذلك لأمتلاكة نفس قیم العزوم السبعة .ً


Article
A Selective Image Encryption Based on Chaos Algorithm

Authors: Abeer Matti Yousif --- Manaf Mohammed Ali
Journal: journal of kerbala university مجلة جامعة كربلاء ISSN: 18130410 Year: 2013 Volume: 11 Issue: 1 Pages: 136-149
Publisher: Kerbala University جامعة كربلاء

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Abstract

Selective encryption is a new trend in image and video content protection. It's aim to reduce the amount of data to protect while preserving a sufficient level of security by connected with chaotic theory. Due to their features of ergodicity, sensitivity to initial conditions, pseudo randomly, chaotic maps have good potential for information encryption. In this work, selective image encryption based on chaos algorithm has suggested, This technique adopted two main operations one to decorrelate the relationship between adjacent pixels of plain image which is based on 2D Chaotic Standard map and the other to decorrelate the relationship between the plain image and encrypted image which is based on 4D Chaotic Map. Experimental results show that the proposed scheme is computationally secure, it withstands different types of attacks such as brute force attack, differential attack, chosen-plaintext and chosen-ciphertext attacks. Also, Experimental results show that the proposed scheme is suitable for multimedia application with real time operation. Where the average execution time is (1 second) when the encryption ratio is equal to (6.25 %).

التشفير الانتقائي هو توجه جديد في حماية محتوى الصور والفيديو .فهو يهدف إلى تقليل من كمية البيانات المخصصة للتشفير مع الحفاظ على مستوى كافي من الأمان من خلال الترابط مع نظرية التشويش. نظرا لما تمتلكه من خصائص مثل (ergodicity), الحساسية للظروف الأولية, ظهورها بشكل أشبه بالعشوائي, نظرية التشويش تنطوي على إمكانية جيدة في تشفير المعلومات. في هذا البحث, أقترح تشفير الصورة الانتقائي بالاعتماد على خوارزمية التشويش, هذه التقنية تبنت عمليتين أساسيتين واحدة لتفكيك العلاقة بين نقاط الصورة المتجاورة للصورة المراد تشفيرها والتي تقوم على أساس معادلة التشويش القياسية ثنائية البعد والأخرى لتفكيك العلاقة بين الصورة الأصلية والصورة المشفرة والتي اعتمدت على معادلة التشويش رباعية البعد. وقد أظهرت النتائج أن المنظومة المقترحة هي(computationally secure ) , فإنها تقاوم أنواع مختلفة من الهجمات مثل هجوم القوة, الهجوم التفاضلي, هجمات الصورة المختارة والمشفرة المختارة. كذلك أظهرت النتائج أن المنظومة المقترحة ملائمة لتطبيقات الوسائط المتعددة مع نظام الوقت الحقيقي. حيث معدل وقت التنفيذ هو( ا ثانية ) عندما تكون نسبة التشفير تساوي(6.25%).


Article
A Technique for Image Steganography Based on Optimal Resilient Boolean Functions and DCT

Author: Azhar Malik
Journal: IRAQI JOURNAL OF COMPUTERS,COMMUNICATION AND CONTROL & SYSTEMS ENGINEERING المجلة العراقية لهندسة الحاسبات والاتصالات والسيطرة والنظم ISSN: 18119212 Year: 2013 Volume: 13 Issue: 2 Pages: 71-80
Publisher: University of Technology الجامعة التكنولوجية

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Abstract

Abstract:One of the methods introduced for accomplishing hidden communicationis the steganography technique. Steganography is an important area of research in recentyears involving a number of applications. It is the science of embedding informationinto the cover image, text and video without causing statistically significantmodification to the cover image. This paper proposes an image steganography system; ithides the gray level image on another gray level image by using optimal resilientBoolean functions. First, it starts by encrypting secret image by using optimal resilientfunction then embedding encrypted image inside a cover image by using DCT. The newproposal system of image encryption has been investigated by encrypting the powerfulfrequency coefficients in DCT using a saturated best resilient Boolean function (SRB)that constructed by Zhang's construction. The simulation results of the proposal systemhave calculated the peak signal to noise ratio (PSNR) and the correlation test in order tocompare between the cover image and the stego image and the results have alsocalculated the correlation test between the secrete image and the extraction image as aparameter of robustness. The experimental results have showed that the images can beembedded by steganography and optimal resilient Boolean function with smallercorrelation compared to the original secret image and the extraction image. Finally, it isobserved that for all images, PSNR is greater than 55.


Article
Analyzing Laser Speckle Pattern Using the Discrete Cosine Transform

Author: Inbethaq Mohammed Ali Abdul-Ameer
Journal: Ibn Al-Haitham Journal For Pure And Applied Science مجلة ابن الهيثم للعلوم الصرفة والتطبيقية ISSN: 16094042/ 25213407 Year: 2017 Volume: 30 Issue: 2 Pages: 10-15
Publisher: Baghdad University جامعة بغداد

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Abstract

The use of Cosine transform to analyze the model-noise pattern alteration with different vibration model applied on multimode fiber optics are studied. It's results compared with the Fourier transform to perform the same analysis using total frequency difference and the computation time, which almost coincide for the both transforms. A discussion for the results and recommendation are introduced.


Article
A DISCRETE COSINE TRANSFORM BASED WATERMARKING SCHEME FOR COLOR IMAGE USING YCbCr SPACE

Author: Adel Jalal Yousif
Journal: Journal of Engineering and Sustainable Development مجلة الهندسة والتنمية المستدامة ISSN: 25200917 Year: 2018 Volume: 22 Issue: 6 Pages: 1-12
Publisher: Al-Mustansyriah University الجامعة المستنصرية

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Abstract

: In this paper, a non-blind color image watermarking scheme is proposed based on discrete cosine transform and YCbCr color space. The host image is converted from RGB space into YCbCr space and the Y component image is employed for embedding a binary watermark image. The strength of the watermark is controlled by a robustness factor to obtain an acceptable trade-off between robustness and imperceptibility. The performance of the proposed scheme is evaluated in term of Peak signal to noise ratio (PSNR) and normalized correlation (NC). The experimental results show that the proposed scheme is robust under various attacks like JPEG compression, filtering and noise addition.


Article
A comparative Study for Designing an Efficient Intelligence System for the Process of Discrimination
دراسة مقارنة لتصميم نظام ذكائي كفوء لعملية التمييز

Authors: Iman S. Mohammed --- Shatha A. Mohammed
Journal: JOURNAL OF EDUCATION AND SCIENCE مجلة التربية والعلم ISSN: 1812125X Year: 2019 Volume: 28 Issue: 4 Pages: 206-223
Publisher: Mosul University جامعة الموصل

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Abstract

Face recognition is one of the most important biometrics techniques used to identify people. The research aims to build an efficient system by devising a new method of discrimination that includes advanced image processing techniques and intelligent techniques. This work has been implemented in several stages, the first of which is the arrangement of the database, Followed by pre-processing based on the integration of Gaborand DCT conversion. And then adopt two methods in extracting statistical features, the first dependent first-class statistics, the second dependent second-class statistics of the GLCM matrix and then draw the important features of them. In the phase of discrimination, two types of artificial neural networks were used after their construction in the 2016 MATLAB environment, BPNN and Elman. Finally, the efficiency of the methods used and the identification of the best were compared.

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