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# Obtaining PSSH
## Getting started
3 methods to find PSSH:
1) The simplest one: PSSH is clearly indicated in MPD file. Download MPD file (browser add-on "MPD Detector" will give you MPD link or filtering for `mpd` in the `network` tab of devoloper tools (ctrl + shift + c)), open it with Notepad, search for pssh value.
2) If there is KID, but no PSSH in MPD, calculate PSSH by using KID:
Using [this]( "this") website you can get the PSSH by entering in the `urn:uuid:` into the `System ID` field and entering the `cenc:default_KID=` into the `KEY IDs` field without the quotes `""`
![One:](example_one.png?raw=true "One")
3) [EME Logger Script]( "EME Logger Script") (installed on [Tampermonkey]( "Tampermonkey") add-on) will give you init data. That's your PSSH. This can be found on Developer Tools (ctrl + shift + c) > Console, in the filter bar search for `MediaKeySession::generateRequest` you will find Init Data.
**Optional, may be rquired:**
If that Init Data is very very long, convert it to HEX:
Here's what mine looked like before conversion.
![Two:](example_two.png?raw=true "Two")
After Base64 > HEX conversion, you will find a Widevine-PSSH box, this can be found easily by searching with ctrl + f and searching for `70737368`
PSSH header is always in a `000000xx70737368` where the `xx` is varied and can be from 1-9 in both x spots.
You always want to copy the 6 `0`'s before the xx as well.
![Three:](example_three.png?raw=true "Three")
The end of the header is always then followed by 8 more `0`s, if you see this, you are in the right place.
Once you find the header start at the beginning 0 from the header and copy until the end of the converted hex, it should look like this
![Four:](example_four.png?raw=true "Four")
In this case the full value was `000000577073736800000000edef8ba979d64acea3c827dcd51d21ed0000003708011210162f7d326cf24f6dbd1319bc572bbc151a0b62757964726d6b65796f732210162f7d326cf24f6dbd1319bc572bbc152a024844`
convert the hex back into base64 using
![Five:](example_five.png?raw=true "Five")
In this case we got the PSSH value of `AAAAV3Bzc2gAAAAA7e+LqXnWSs6jyCfc1R0h7QAAADcIARIQFi99MmzyT229Exm8Vyu8FRoLYnV5ZHJta2V5b3MiEBYvfTJs8k9tvRMZvFcrvBUqAkhE`
Congrats, you have the PSSH!
4) Using init files
You can use [this tool]( "this tool") to obtain the PSSH from an init file