I tried Torn edges, but my results are noticeably different from these pictures
2 Answers
From original image - yeah, don't ask ;)
Add adjustment layer - Threshold
Flatten result.
Add layer mask [reveal all].
Select all, copy, alt/click mask, paste.
Invert. This should leave the black but make all the white transparent.
Add new layer, drop it behind.
Use paint bucket with flat purple.
Filter > Noise > Add Noise
result…
My answer is similar to Tetsujin's method, but created non-destructively using a Threshold adjustment layer, grouped with the image layer, then the group set to "Multiply" mode. A noise filter can then be applied to a purple background Smart Object.
For greater similarity to your examples, it's probably best to start off with a photograph taken with low key lighting (i.e. dark background and strong highlights).
Example:
The benefit of doing this non-destructively is you can adjust the Threshold and Noise filters after applying them.