category to log
level of the message
the file that emitted the message, usually the FILE identifier
the function that emitted the message
the line from that the message was emitted, usually LINE
the object this message relates to, or null if none
the actual message
Returns the string representation for the specified debug log message formatted in the same way as
gst_debug_log_default()(the default handler), without color. The purpose is to make it easy for custom log output handlers to get a log output that is identical to what the default handler would write out.