But only a set of byte chunks spread around in the image file to calculate the fingerprint, which is much faster than reading the whole file:
```bash
BenchmarkMD5FromFileFast/full=false-4 300000 4356 ns/op 240 B/op 5 allocs/op
BenchmarkMD5FromFileFast/full=true-4 30000 42899 ns/op 32944 B/op 5 allocs/op
```
Fixes#4186