Format of bootloader-*.img files found in factory images of certain Android devices from Huawei:
All image versions can be found in factory images at https://developers.google.com/android/images for the specific device. To avoid having to download an entire ZIP archive when you only need one file from it, install remotezip and use its command line tool to list members in the archive and then to download only the file you want.
This page hosts a formal specification of Huawei Bootloader packed image format using Kaitai Struct. This specification can be automatically translated into a variety of programming languages to get a parsing library.
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<TR><TD PORT="image_header_pos">...</TD><TD PORT="image_header_size">meta_header.len_image_header</TD><TD>ImageHdr</TD><TD PORT="image_header_type">image_header</TD></TR>
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