ffmpeg/doc/metadata.texi

   1 @chapter Metadata
   2 @c man begin METADATA
   3
   4 FFmpeg is able to dump metadata from media files into a simple UTF-8-encoded
   5 INI-like text file and then load it back using the metadata muxer/demuxer.
   6
   7 The file format is as follows:
   8 @enumerate
   9
  10 @item
  11 A file consists of a header and a number of metadata tags divided into sections,
  12 each on its own line.
  13
  14 @item
  15 The header is a ';FFMETADATA' string, followed by a version number (now 1).
  16
  17 @item
  18 Metadata tags are of the form 'key=value'
  19
  20 @item
  21 Immediately after header follows global metadata
  22
  23 @item
  24 After global metadata there may be sections with per-stream/per-chapter
  25 metadata.
  26
  27 @item
  28 A section starts with the section name in uppercase (i.e. STREAM or CHAPTER) in
  29 brackets ('[', ']') and ends with next section or end of file.
  30
  31 @item
  32 At the beginning of a chapter section there may be an optional timebase to be
  33 used for start/end values. It must be in form 'TIMEBASE=num/den', where num and
  34 den are integers. If the timebase is missing then start/end times are assumed to
  35 be in milliseconds.
  36 Next a chapter section must contain chapter start and end times in form
  37 'START=num', 'END=num', where num is a positive integer.
  38
  39 @item
  40 Empty lines and lines starting with ';' or '#' are ignored.
  41
  42 @item
  43 Metadata keys or values containing special characters ('=', ';', '#', '\' and a
  44 newline) must be escaped with a backslash '\'.
  45
  46 @item
  47 Note that whitespace in metadata (e.g. foo = bar) is considered to be a part of
  48 the tag (in the example above key is 'foo ', value is ' bar').
  49 @end enumerate
  50
  51 A ffmetadata file might look like this:
  52 @example
  53 ;FFMETADATA1
  54 title=bike\\shed
  55 ;this is a comment
  56 artist=FFmpeg troll team
  57
  58 [CHAPTER]
  59 TIMEBASE=1/1000
  60 START=0
  61 #chapter ends at 0:01:00
  62 END=60000
  63 title=chapter \#1
  64 [STREAM]
  65 title=multi\
  66 line
  67 @end example
  68
  69 By using the ffmetadata muxer and demuxer it is possible to extract
  70 metadata from an input file to an ffmetadata file, and then transcode
  71 the file into an output file with the edited ffmetadata file.
  72
  73 Extracting an ffmetadata file with @file{ffmpeg} goes as follows:
  74 @example
  75 ffmpeg -i INPUT -f ffmetadata FFMETADATAFILE
  76 @end example
  77
  78 Reinserting edited metadata information from the FFMETADATAFILE file can
  79 be done as:
  80 @example
  81 ffmpeg -i INPUT -i FFMETADATAFILE -map_metadata 1 -codec copy OUTPUT
  82 @end example
  83
  84 @c man end METADATA