/// <summary>
        /// Gets the type identifier for the auxiliary image.
        /// </summary>
        /// <returns>The type identifier for the auxiliary image.</returns>
        /// <exception cref="HeifException">A LibHeif error occurred.</exception>
        /// <exception cref="ObjectDisposedException">The object has been disposed.</exception>
        public string GetAuxiliaryType()
        {
            VerifyNotDisposed();

            string type = string.Empty;

            if (this.auxiliaryImageType == AuxiliaryImageType.VendorSpecific)
            {
                var error = LibHeifNative.heif_image_handle_get_auxiliary_type(this.imageHandle,
                                                                               out var typePtr);
                error.ThrowIfError();

                try
                {
                    type = typePtr.GetStringValue();
                }
                finally
                {
                    LibHeifNative.heif_image_handle_free_auxiliary_types(this.imageHandle,
                                                                         ref typePtr);
                }
            }

            return(type);
        }