منابع مشابه
Image Compression By Embedding Five Modulus Method Into JPEG
The standard JPEG format is almost the optimum format in image compression. The compression ratio in JPEG sometimes reaches 30:1. The compression ratio of JPEG could be increased by embedding the Five Modulus Method (FMM) into the JPEG algorithm. The novel algorithm gives twice the time as the standard JPEG algorithm or more. The novel algorithm was called FJPEG (Five-JPEG). The quality of the ...
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Digital image compression algorithms have become increasingly popular due to the need to achieve coste ective solutions in transmitting and storing images. In order to meet various transmission and storage requirements, the compression algorithm should allow a range of compression ratios, thus providing images of di erent visual quality. This paper presents a modi ed JPEG algorithm that provide...
متن کاملThe Jpeg Image Compression Algorithm
The basis for the JPEG algorithm is the Discrete Cosine Transform (DCT) which extracts spatial frequency information from the spatial amplitude samples. These frequency components are then quantized to eliminate the visual data from the image that is least perceptually apparent, thereby reducing the amount of information that must be stored. The redundant properties of the quantized frequency s...
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This paper presents a robust image authentication approach that distinguishes malicious attacks from JPEG lossy compression. The authentication procedure calculates the relationships between important DCT coefficients in each pair of DCT blocks and predefined thresholds to form the authentication message, and then embeds the encryption of the authenticated message into other DCT coefficients. T...
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ژورنال
عنوان ژورنال: Japanese Journal of Radiological Technology
سال: 1992
ISSN: 0369-4305,1881-4883
DOI: 10.6009/jjrt.kj00003500923