decompress

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decompress

(dē″kŏm-prĕs′)
1. To pass from a state of stress to tranquillity.
2. To relieve pressure, esp. that produced by air or gas.
References in periodicals archive ?
N] stand for JPEG decompressed images with N kinds of different quality factors, while IN+1 stands for the uncompressed image.
If the forensics classifier A in charge of identifying JPEG decompressed images is balanced, i.
Where [MATHEMATICAL EXPRESSION NOT REPRODUCIBLE IN ASCII] indicate the probabilities that the forensics classifier A makes a correct and a wrong decision for JPEG decompressed images, respectively.
Finally we get the final JPEG decompressed images after decompression.
The cover database contains both uncompressed bitmap images and corresponding JPEG decompressed bitmap images with ten kinds of different quality factors.
For our experiments, two targeted steganalyzers (named LLTCF [11] and RDIH [12]) for LSB matching steganography, one targeted steganalyzer (named CAM [13]) designed for LSB matching steganography in JPEG decompressed images, one blind steganalyzer (named 1D [14]) for additive noise steganography in JPEG decompressed images and two blind steganalyzers (named WAM [15] and LLTPDF [16]) are taken into consideration.
4) CAM: the first 10 order central absolute moments of noise residuals in DCT domain of JPEG decompressed images;
9 shows the histograms among mixed covers and stegos at embedding rates 25% and 100% between uncompressed images and JPEG decompressed images with quality factors 90 and 95.
For a given embedding rate in the training stage, half of the uncompressed images (covers and stegos) and the corresponding JPEG decompressed images (covers and stegos) with QF=95, the highest quality factor the proposed feature can detect reliably, are employed to obtain a proper threshold.
In our experiment, for a given JPEG decompressed image (cover and stego), we recompress it with all the candidate tables and obtain the corresponding recompressed versions in the spatial domain, and thus (12) is employed for the quality factor estimation.
Please note that the accuracy is relatively lower for detecting the JPEG decompressed images with QFs=50 and 75.
i,k] be the number that a JPEG decompressed image identifier assigns cover images coming from [I.