| @chapter Metadata |
| @c man begin METADATA |
| |
| FFmpeg is able to dump metadata from media files into a simple UTF-8-encoded |
| INI-like text file and then load it back using the metadata muxer/demuxer. |
| |
| The file format is as follows: |
| @enumerate |
| |
| @item |
| A file consists of a header and a number of metadata tags divided into sections, |
| each on its own line. |
| |
| @item |
| The header is a ';FFMETADATA' string, followed by a version number (now 1). |
| |
| @item |
| Metadata tags are of the form 'key=value' |
| |
| @item |
| Immediately after header follows global metadata |
| |
| @item |
| After global metadata there may be sections with per-stream/per-chapter |
| metadata. |
| |
| @item |
| A section starts with the section name in uppercase (i.e. STREAM or CHAPTER) in |
| brackets ('[', ']') and ends with next section or end of file. |
| |
| @item |
| At the beginning of a chapter section there may be an optional timebase to be |
| used for start/end values. It must be in form 'TIMEBASE=num/den', where num and |
| den are integers. If the timebase is missing then start/end times are assumed to |
| be in milliseconds. |
| Next a chapter section must contain chapter start and end times in form |
| 'START=num', 'END=num', where num is a positive integer. |
| |
| @item |
| Empty lines and lines starting with ';' or '#' are ignored. |
| |
| @item |
| Metadata keys or values containing special characters ('=', ';', '#', '\' and a |
| newline) must be escaped with a backslash '\'. |
| |
| @item |
| Note that whitespace in metadata (e.g. foo = bar) is considered to be a part of |
| the tag (in the example above key is 'foo ', value is ' bar'). |
| @end enumerate |
| |
| A ffmetadata file might look like this: |
| @example |
| ;FFMETADATA1 |
| title=bike\\shed |
| ;this is a comment |
| artist=FFmpeg troll team |
| |
| [CHAPTER] |
| TIMEBASE=1/1000 |
| START=0 |
| #chapter ends at 0:01:00 |
| END=60000 |
| title=chapter \#1 |
| [STREAM] |
| title=multi\ |
| line |
| @end example |
| |
| By using the ffmetadata muxer and demuxer it is possible to extract |
| metadata from an input file to an ffmetadata file, and then transcode |
| the file into an output file with the edited ffmetadata file. |
| |
| Extracting an ffmetadata file with @file{ffmpeg} goes as follows: |
| @example |
| ffmpeg -i INPUT -f ffmetadata FFMETADATAFILE |
| @end example |
| |
| Reinserting edited metadata information from the FFMETADATAFILE file can |
| be done as: |
| @example |
| ffmpeg -i INPUT -i FFMETADATAFILE -map_metadata 1 -codec copy OUTPUT |
| @end example |
| |
| @c man end METADATA |