# Customize existing sample applications

To modify the sample applications, use the `devtool` utility from the eSDK to get the source code for sample applications.
After making the required changes, use the `devtool` utility to compile and package the applications into an installable format (`ipk`).

Download and compile the existing sample application using the
`devtool` utility of Yocto.

1. Download the source:

    1. Go to the directory where the eSDK was installed:

cd <workspace root>
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        In the command, `<workspace_root>` is the file system path where
the eSDK is installed.
    2. Set up the source environment:

source environment-setup-armv8-2a-qcom-linux
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    3. Download the sample application sources:

devtool modify qcom-gst-camera-single-stream-example
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    The command `devtool modify` initializes the workspace and
downloads the sample applications from the repository.

    The sources are at `<workspace_root>/workspace/sources/qcom-gst-camera-single-stream-example`.
2. Build the application:

    1. After you do the necessary customizations, run the following
command to recompile:

devtool build qcom-gst-camera-single-stream-example
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    2. Generate an installable IPK file:

devtool package qcom-gst-camera-single-stream-example
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    The installable packages are at `<workspace_root>/tmp/deploy/ipk/armv8-2a/`.
3. Install the updated application:

    1. Push the application on the target device:

opkg --force-reinstall install <.ipk that was generated >
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        For example:

opkg --force-reinstall install qcom-gst-camera-single-stream-example\_1.0-r0\_armv8-2a.ipk

Last Published: Dec 30, 2024

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