How to use the command 'rpicam-raw' (with examples)
- Linux
- December 17, 2024
The rpicam-raw
command is an invaluable tool for anyone working with Raspberry Pi cameras. It provides a simple yet powerful way to capture raw video footage directly from the camera connected to your Raspberry Pi. This command is part of a broader suite of camera software utilities that allow for capturing high-quality video and stills, with a range of options to customize the capture settings to suit your needs.
Use case 1: Capture a video for a specific amount of seconds
Code:
rpicam-raw -t 2000 -o path/to/file.raw
Motivation:
Capturing a video for a specified duration is one of the most common requirements when working with a camera setup. Whether it’s for a time-lapse, scientific research, or simply for creating a short clip, specifying the capture time is essential. For instance, you might want to capture a brief moment at an event or monitor a specific activity for a limited period. Using the -t
(time) parameter allows you to control exactly how long the camera will record, ensuring you don’t generate unnecessarily large files or too much data.
Explanation:
rpicam-raw
: This is the command used to record video from the Raspberry Pi’s camera in raw format.-t 2000
: The-t
flag specifies the duration of the recording in milliseconds. Here,2000
means the camera will capture footage for 2000 milliseconds, or 2 seconds.-o path/to/file.raw
: This option specifies the output file where the captured raw video will be saved. You will need to replacepath/to/file.raw
with the actual path where you want the file to be saved.
Example output:
Upon execution, the command will record 2 seconds of video and save it to the specified file path. There is no on-screen display output when using rpicam-raw
, as it directly handles the video capturing process. You would see a new file named file.raw
in your specified directory, containing the raw video footage.
Use case 2: Change video dimensions and framerate
Code:
rpicam-raw -t 5000 --width 4056 --height 3040 -o path/to/file.raw --framerate 8
Motivation:
Changing the video dimensions and framerate is critical for capturing footage that meets specific needs, such as high-resolution video for detailed analysis or ensuring compatibility with your playback device or software. Different scenarios and projects demand different video qualities and characteristics. For example, in applications like wildlife monitoring or scientific experiments, you might need a higher resolution to capture every detail, while a lower framerate can save on storage space and processing power when capturing slow movements.
Explanation:
rpicam-raw
: The core command to start capturing a raw video feed from the camera.-t 5000
: Sets the capture duration to 5000 milliseconds or 5 seconds.--width 4056
: This option sets the width of the video frame to 4056 pixels, specifying the horizontal resolution.--height 3040
: This sets the height of the video frame to 3040 pixels, specifying the vertical resolution.-o path/to/file.raw
: Directs the command to save the captured footage to the given file path.--framerate 8
: Specifies the frames per second (fps) for the video recording. A setting of 8 fps means 8 frames are captured each second.
Example output:
After running this command, the Raspberry Pi camera will capture 5 seconds of video at a resolution of 4056x3040 pixels with a framerate of 8 fps. The result will be saved in the designated file path. Similar to the first use case, the output will be the creation of a new raw file in the specified location, containing the high-resolution video footage.
Conclusion:
The rpicam-raw
command is an excellent tool for utilizing the full potential of Raspberry Pi cameras. By understanding and utilizing its various options, such as capture duration, output file specification, and customizable video settings, users can adapt to a diverse range of recording scenarios effectively. These examples demonstrate how users can leverage specific command options to produce high-quality, tailored video captures for any application involving Raspberry Pi camera modules.