WhatIs: Backdoor

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If there is a method for a computer to receive commands from someone else instead of the user, that method is called a backdoor. Backdoors that allow full control over the operating system are said to be "universal".

There can be backdoors in hardware or software.

Sometimes, backdoors that are designed for "legitimate" uses are exploited illegitimately.

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Intel 7th and 8th generation processor graphics driver for Windows 7/8/8.1

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In this part, we tested the lossy compression capability. "Lossy" means that in order to reduce data size, the data is inexactly approximated and part of it is discarded. To measure the fidelity of the reconstruction (encoded video) of lossy compression codecs in our tests, we used PSNR (Peak signal-to-noise ratio). The greater the PSNR of two videos, the more similar they are. If the encoded video is lossless, the PSNR will be infinity when compared to the original. We tried to match the PSNR and compared the video stream size, the smaller the size, the better the codec. But it is hard to make the PSNR exactly the same. As mentioned earlier, as of June 2018, the AV1 is still experimental and we were not able to set its constant quality mode as we expected. And AV1 is extremely slow. So we did the AV1 in its vibrate bitrate mode first. We have found that the VP9 produces better results when encoded in its 2-pass constant quality mode (can be set with "-crf"), so
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Install VMAF on Fedora, CentOS/Red Hat (RHEL)

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