pssh-box - Utility to parse and generate PSSH boxes
===================================================

## Prerequisite

- Python 3.

## Build the utility using Shaka Packager build setup

The utility needs to be built before being used, i.e. do not use the script in
`packager/tools/pssh/pssh_box.py` directly.

If you have not set up the build environment for Shaka Packager, see
https://github.com/shaka-project/shaka-packager/blob/master/docs/source/build_instructions.md.

With the build environment set up, use `ninja` to build the utility:

```bash
$ ninja -C build/ pssh-box.py
```

Then you can use the built utility in `build/pssh-box.py`.

## Usage

All examples below assume that that `pssh-box.py` is in the `PATH` variable of
the executing shell.

### PSSH box generation

The utility can be used to generate one or more PSSH boxes.

An example to generate a Widevine PSSH with content-id 1234:

```bash
$ pssh-box.py --widevine-system-id --content-id 1234
```

It can be also be used to generate PSSH box from PSSH data (base64), e.g.

```bash
$ pssh-box.py --widevine-system-id --pssh-data AAAABCICEjQ=
```

The output can be in base64 form (`--base64`), in hex form (`--hex`) or in human
readable form (`--human`). Human readable form is the default.

An example to generate a Widevine PSSH with content-id 1234 in hex:

```bash
$ pssh-box.py --widevine-system-id --content-id 1234 --hex
```

Multiple boxes can be generated by separating boxes with `--`.

An example to generate concatenated PSSHs with a Widevine PSSH with content-id
1234 and a common PSSH with key-id 31323334353637383930313233343536 (hex form).

```bash
$ pssh-box.py \
  --widevine-system-id --content-id 1234 -- \
  --common-system-id --key-id 31323334353637383930313233343536
```

### PSSH box parsing

The utility can be used to parse a single PSSH box or multiple concatenated PSSH
boxes. The input can be in hex or in base64.

```bash
$ pssh-box.py --from-hex \
  000000247073736800000000EDEF8BA979D64ACEA3C827DCD51D21ED0000000422021234
```

```bash
$ pssh-box.py --from-base64 AAAAJHBzc2gAAAAA7e+LqXnWSs6jyCfc1R0h7QAAAAQiAhI0
```

### More options

Run the utility with no arguments to see the full list of options.

```bash
$ pssh-box.py
```