| @chapter Syntax |
| @c man begin SYNTAX |
| |
| When evaluating specific formats, FFmpeg uses internal library parsing |
| functions, shared by the tools. This section documents the syntax of |
| some of these formats. |
| |
| @anchor{date syntax} |
| @section Date |
| |
| The accepted syntax is: |
| @example |
| [(YYYY-MM-DD|YYYYMMDD)[T|t| ]]((HH:MM:SS[.m...]]])|(HHMMSS[.m...]]]))[Z] |
| now |
| @end example |
| |
| If the value is "now" it takes the current time. |
| |
| Time is local time unless Z is appended, in which case it is |
| interpreted as UTC. |
| If the year-month-day part is not specified it takes the current |
| year-month-day. |
| |
| @anchor{time duration syntax} |
| @section Time duration |
| |
| The accepted syntax is: |
| @example |
| [-]HH:MM:SS[.m...] |
| [-]S+[.m...] |
| @end example |
| |
| @var{HH} expresses the number of hours, @var{MM} the number a of minutes |
| and @var{SS} the number of seconds. |
| |
| @anchor{video size syntax} |
| @section Video size |
| Specify the size of the sourced video, it may be a string of the form |
| @var{width}x@var{height}, or the name of a size abbreviation. |
| |
| The following abbreviations are recognized: |
| @table @samp |
| @item sqcif |
| 128x96 |
| @item qcif |
| 176x144 |
| @item cif |
| 352x288 |
| @item 4cif |
| 704x576 |
| @item 16cif |
| 1408x1152 |
| @item qqvga |
| 160x120 |
| @item qvga |
| 320x240 |
| @item vga |
| 640x480 |
| @item svga |
| 800x600 |
| @item xga |
| 1024x768 |
| @item uxga |
| 1600x1200 |
| @item qxga |
| 2048x1536 |
| @item sxga |
| 1280x1024 |
| @item qsxga |
| 2560x2048 |
| @item hsxga |
| 5120x4096 |
| @item wvga |
| 852x480 |
| @item wxga |
| 1366x768 |
| @item wsxga |
| 1600x1024 |
| @item wuxga |
| 1920x1200 |
| @item woxga |
| 2560x1600 |
| @item wqsxga |
| 3200x2048 |
| @item wquxga |
| 3840x2400 |
| @item whsxga |
| 6400x4096 |
| @item whuxga |
| 7680x4800 |
| @item cga |
| 320x200 |
| @item ega |
| 640x350 |
| @item hd480 |
| 852x480 |
| @item hd720 |
| 1280x720 |
| @item hd1080 |
| 1920x1080 |
| @end table |
| |
| @anchor{video rate syntax} |
| @section Video rate |
| |
| Specify the frame rate of a video, expressed as the number of frames |
| generated per second. It has to be a string in the format |
| @var{frame_rate_num}/@var{frame_rate_den}, an integer number, a float |
| number or a valid video frame rate abbreviation. |
| |
| The following abbreviations are recognized: |
| @table @samp |
| @item ntsc |
| 30000/1001 |
| @item pal |
| 25/1 |
| @item qntsc |
| 30000/1 |
| @item qpal |
| 25/1 |
| @item sntsc |
| 30000/1 |
| @item spal |
| 25/1 |
| @item film |
| 24/1 |
| @item ntsc-film |
| 24000/1 |
| @end table |
| |
| @anchor{ratio syntax} |
| @section Ratio |
| |
| A ratio can be expressed as an expression, or in the form |
| @var{numerator}:@var{denominator}. |
| |
| Note that a ratio with infinite (1/0) or negative value is |
| considered valid, so you should check on the returned value if you |
| want to exclude those values. |
| |
| The undefined value can be expressed using the "0:0" string. |
| |
| @anchor{color syntax} |
| @section Color |
| |
| It can be the name of a color (case insensitive match) or a |
| [0x|#]RRGGBB[AA] sequence, possibly followed by "@" and a string |
| representing the alpha component. |
| |
| The alpha component may be a string composed by "0x" followed by an |
| hexadecimal number or a decimal number between 0.0 and 1.0, which |
| represents the opacity value (0x00/0.0 means completely transparent, |
| 0xff/1.0 completely opaque). |
| If the alpha component is not specified then 0xff is assumed. |
| |
| The string "random" will result in a random color. |
| |
| @c man end SYNTAX |