example of using boost log, which includes stdout, file output, log rotation, message format

log-system.cpp

#include <boost/log/core.hpp>
#include <boost/log/expressions.hpp>
#include <boost/log/sinks/text_file_backend.hpp>
#include <boost/log/sources/record_ostream.hpp>
#include <boost/log/sources/severity_logger.hpp>
#include <boost/log/trivial.hpp>
#include <boost/log/utility/setup/common_attributes.hpp>
#include <boost/log/utility/setup/console.hpp>
#include <boost/log/utility/setup/file.hpp>

namespace is = ImageStitching;
namespace logging = boost::log;
namespace src = boost::log::sources;
namespace sinks = boost::log::sinks;
namespace keywords = boost::log::keywords;

void log_init() {
    logging::register_simple_formatter_factory<
        boost::log::trivial::severity_level, char>("Severity");

    logging::add_file_log(
        keywords::target = "logs/", keywords::file_name = "%y%m%d_%3N.log",
        keywords::rotation_size = 10 * 1024 * 1024,
        keywords::scan_method = sinks::file::scan_matching,
        keywords::format = "[%TimeStamp%][%Severity%]: %Message%");

    logging::add_console_log(std::cout,
                             boost::log::keywords::format = ">> %Message%");

    logging::core::get()->set_filter(logging::trivial::severity >=
                                     logging::trivial::info);
}