Function JxlDecoderSetMultithreadedImageOutCallback 

pub unsafe extern "C-unwind" fn JxlDecoderSetMultithreadedImageOutCallback(
    dec: *mut JxlDecoder,
    format: *const JxlPixelFormat,
    init_callback: JxlImageOutInitCallback,
    run_callback: JxlImageOutRunCallback,
    destroy_callback: JxlImageOutDestroyCallback,
    init_opaque: *mut c_void,
) -> JxlDecoderStatus

Similar to JxlDecoderSetImageOutCallback except that the callback is allowed an initialization phase during which it is informed of how many threads will call it concurrently, and those calls are further informed of which thread they are occurring in.

Parameters

• dec: decoder object
• format: format of the pixels. Object owned by user; its contents are copied internally.
• init_callback: initialization callback.
• run_callback: the callback function receiving partial scanlines of pixel data.
• destroy_callback: clean-up callback invoked after all calls to run_callback. May be NULL if no clean-up is necessary.
• init_opaque: optional user data passed to init_callback, may be NULL (unlike the return value from init_callback which may only be NULL if initialization failed).

Returns

• JxlDecoderStatus::Success on success, JxlDecoderStatus::Error on error, such as JxlDecoderSetImageOutBuffer having already been called.