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Re:How the Xbox 360 knows if your hard-drive is genuine by userbinator on Wednesday January 25, 2023 @12:52AM (#34514890)
Yes, that's called HDCP. The master key was cracked long ago for older versions.
Re:How the Xbox 360 knows if your hard-drive is genuine by toast0 on Wednesday January 25, 2023 @01:27AM (#34515076)
For new versions, you can get a converter; hdcp 2.2 -> hdcp 1.4 and then use whatevee breakage on 1.4. So it's only effective if you don't search.
Re:How the Xbox 360 knows if your hard-drive is genuine by lfodofod on Wednesday January 25, 2023 @04:40AM (#34516376)
You can’t produce good quality rips like this, if that was the best solution the DRM people would have won.
Re:How the Xbox 360 knows if your hard-drive is genuine by callesgg on Wednesday January 25, 2023 @05:42AM (#34516754)
You can produce pixel perfect rips. But since the resulting video file is so large you will "need" to compress it, and then you get compression on compression artefacts.
Re:How the Xbox 360 knows if your hard-drive is genuine by lfodofod on Wednesday January 25, 2023 @07:32AM (#34517482)
Yes, indeed. Pixel perfect rips of already compressed streams, immensely blowing up the size and requiring another round of lossy compression to actually be useful.
Re:How the Xbox 360 knows if your hard-drive is genuine by tjoff on Thursday January 26, 2023 @02:31AM (#34528750)
And the result after recompression is impeccable so it is not a big deal. It is just a bit cumbersome.
Re:How the Xbox 360 knows if your hard-drive is genuine by lfodofod on Thursday January 26, 2023 @03:10AM (#34529048)
The result after recompression is far from impeccable.
Re:How the Xbox 360 knows if your hard-drive is genuine by tjoff on Thursday January 26, 2023 @03:58AM (#34529352)
On high bitrate content you wouldn't notice.
Re:How the Xbox 360 knows if your hard-drive is genuine by lfodofod on Thursday January 26, 2023 @04:58AM (#34529766)
Sure, but you get to push your encoder settings far less than you otherwise could. You always end up with either significantly bigger files or significantly lower quality.
Re:How the Xbox 360 knows if your hard-drive is genuine by Dylan16807 on Saturday January 28, 2023 @02:36AM (#34555941)
It's significant closer to 5 percent or 50 percent?
Re:How the Xbox 360 knows if your hard-drive is genuine by kevincox on Wednesday January 25, 2023 @12:28PM (#34521250)
It would be really interesting to make a video compressor that specializes in "recompressing" previously compressed data. A simple version could be special handling of common compression artifacts and trying to detect various transforms and trying to take advantage of the detail already removed instead of removing additional detail.

If you knew the codec used originally you could even try to (near) perfectly reconstruct the original bitstream. Especially if you know various codec parameters and some side-channel data (such as which video data is contained in which encrypted blocks) it may be possible to relatively efficiently search for the bitstream that decompresses to the data that you are seeing.