libdovi call functions and data structures

[MCFFHAB]

@quietvoid , thank you for this great tool. I have use dovi_tool but now I am starting to use libdovi with CoreELEC and was looking for a list of the c api call functions and data structures available. Specifically I would like to read the rpu from the video stream, make changes to specific rpu values, and the write it back to the video stream. For example, on CoreELEC/Kodi there is this code that reads the rpu level 0 metadata for source min and max values but I was wondering what are the other libdovi data structures for the other elements of the rpu level 0?:

'''
if (first_frame) {

DOVIStreamMetadata dovi_stream_metadata;

if (vdr_dm_data) 
{
  dovi_stream_metadata.source_min_pq = vdr_dm_data->source_min_pq;
  dovi_stream_metadata.source_max_pq = vdr_dm_data->source_max_pq;
}

'''

Thank you for your help.

[quietvoid]

Read the include header of the lib, it contains all the functions.
And for the structs: https://github.com/quietvoid/dovi_tool/tree/main/dolby_vision/src/c_structs

[MCFFHAB]

@quietvoid Ok, will do, but I would love to have any documentation that you can provide or point me to on the rpu structure (byte location, size, elements, etc...) for Dolby, HDR10+, etc... files / streams. I would need this info in any case. Thank you again.

[MCFFHAB]

@quietvoid , I looked at the Rust code and a have a question - from a very simplistic view, will it work if I create a new libdovi function based on dovi_parse_unspec62_nalu that would not be defined as "const" along with associated rpu structs that would also not be defined as "const" so the rpu values could be changed on a C/C++ program and then have the existing dovi_write_unspec62_nalu function to write the rpu back?

Thank you again for all of your help.

[quietvoid]

No, as I said you need to do it in the Rust code.
In C all you have is the opaque pointer. Any change in the C structs have no effect.

[MCFFHAB]

Ok, thank you, I need to call these new Rust functions from the C/C++ CoreELEC/Kodi code since this is part of some improvements we are trying to do to solve on playing some DV problematic files. Can I call this changes that I would do in Rust code from the CoreELEC/Kodia C/C++ programs? Sorry but not sure the best way to do this yet. Thank You.

[quietvoid]

Can I call this changes that I would do in Rust code from the CoreELEC/Kodia C/C++ programs

As long as the changes are used through the C API functions.

I'm not here to help you with the basics.
Read about Rust FFI to C and figure it out.

The code already exists for anything you need to do. It probably just needs a C function for your specific changes.