Comment by kuschku
2 months ago
Even with DRM video you can fetch it losslessly. At some point, some part of your system requires access to the raw, decrypted video stream.
As long as that's the case, you can get bit-perfect netflix rips.
2 months ago
Even with DRM video you can fetch it losslessly. At some point, some part of your system requires access to the raw, decrypted video stream.
As long as that's the case, you can get bit-perfect netflix rips.
The problem is that if you have the raw data, you’ve lost the original compression information, so you can’t get it back to a sensible size without double compressing. e.g. Think about what you get when you save a jpeg as a bitmap.
You can get the original compressed h264/h265/etc stream back out, that's the entire point.
Even DRM media is using regular accelerated video decode.
The "entire point" of contemporary lossy-media DRM [0] is to prevent you from doing that. You can only do so if the DRM scheme is circumvented or unsound [1].
That is not what we're talking about - the working assumption here is that the DRM scheme is sound and effective. In which case your only possible but also guaranteed stage of recapture is at the analog hole, by which point the media encoding is already undone, incurring a generational loss.
[0] I consider presently existing and historical DRM implementations deeply flawed and misguided; they severely overstep their boundaries implied by the name "DRM", in certain cases quite disgustingly - hence the many added adjectives for clarification
[1] puzzlingly, any access control will actually get you in the same legal situation, regardless of whether the access control mechanism is effective or sound, so this is actually a design decision; but it's pretty universally taken afaik.
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