# Basic Usage

## Getting help

```shell
$ packager --help
```

## Media file analysis

Shaka Packager can be used to inspect the content of a media file and dump basic
stream information.

```shell
$ packager input=some_content.mp4 --dump_stream_info
```

The output looks like:

```shell
File "some_content.mp4":
Found 2 stream(s).
Stream [0] type: Video
 codec_string: avc1.4d001e
 time_scale: 24000
 duration: 3002000 (125.1 seconds)
 is_encrypted: false
 codec: H264
 width: 720
 height: 360
 pixel_aspect_ratio: 8:9
 trick_play_factor: 0
 nalu_length_size: 4

Stream [1] type: Audio
 codec_string: mp4a.40.2
 time_scale: 44100
 duration: 5517311 (125.1 seconds)
 is_encrypted: false
 codec: AAC
 sample_bits: 16
 num_channels: 2
 sampling_frequency: 44100
 language: eng
```

## Basic transmuxing

Shaka Packager can be used to extract streams, optionally transmuxes the streams
from one container format to another container format.

Here is a simple command that extracts video and audio from the input file:

```shell
$ packager in=some_content.mp4,stream=video,out=video.mp4 \
           in=some_content.mp4,stream=audio,out=audio.mp4
```

Shaka Packager is also capable of more complex tasks, such as applying
encryption, packaging contents to DASH or HLS formats, etc. Refer
:doc:`tutorials`.