ERROR: aom >= 0.1.0 not found using pkg-config

I am following this tutorial: https://github.com/gpac/gpac/wiki/GPAC-Build-Guide-for-Android

<GPAC_ROOT_DIR>/deps_android/build/android$ ./gpac_build_all_extra_libs /opt/android-ndk

Using Ubuntu 18 x64

ERROR: aom >= 0.1.0 not found using pkg-config
This is a GitHub Issue
repo:gpac
owner:gpac
Title : ERROR: aom >= 0.1.0 not found using pkg-config
Issue date:

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ERROR: aom >= 0.1.0 not found using pkg-config

I am following this tutorial: https://github.com/gpac/gpac/wiki/GPAC-Build-Guide-for-Android

<GPAC_ROOT_DIR>/deps_android/build/android$ ./gpac_build_all_extra_libs /opt/android-ndk

Using Ubuntu 18 x64

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