FFMPEG Logging System

• include reference ffmpeg header file
• av_log_set_level(AV_LOG_DEBUG) Set the ffmpeg log level, the debug level is the lowest level of ffmpeg
• av_log(NULL, AV_LOG_INFO, “…%S\N”, op) Print the log. The first parameter is generally set to NULL, which is ignored first. Later, the second parameter is the log level, and the third parameter is available.Variable parameters, usage is similar to printf.

Common log levels

• AV_LOG_ERROR
• AV_LOG_WARNING
• AV_LOG_INFO
• AV_LOG_DEBUG
  The print levels of these are decreasing from top to bottom, that is, ERROR is the highest and DEBUG is the lowest. When set to DEBUG, all logs are printed.

INFO is to print when entering an important link, and INFO is mainly used for output.
DEBUG is used for debugging, see if the value is correct.
WARNING is when the program goes to something it should not go to
ERROR is when the program goes to the wrong branch, and the program affects the runtime