Appendix D - MPlayer skin format

The purpose of this document is to describe the MPlayer skin format. The information contained here might be wrong, for

It is not me who wrote the GUI.
The GUI is not finished.
I might be wrong.

So do not be surprised if something does not work as described here.

Thanks to Zoltán Ponekker for his help.

András Mohari <mayday@freemail.hu>

D.1 Overview

It does not really have anything to do with the skin format, but you should know that MPlayer has no builtin skin, so at least one skin must be installed in order to be able to use the GUI.

D.1.1 Directories

The directories searched for skins are (in order):

    $(DATADIR)/Skin/
    $(PREFIX)/share/mplayer/Skin/
    ~/.mplayer/Skin/

Note that the first path may vary according to the way MPlayer was configured (see the --prefix and --datadir arguments of the configure script).

Every skin is installed into its own directory under one of the directories listed above, for example:

    $(PREFIX)/share/mplayer/Skin/default/

D.1.2 Image formats

Images must be truecolor (24 or 32 bpp) PNGs.

In the main window and in the playbar (see below) you can use images with `transparency': Regions filled with the color #FF00FF (magenta) are fully transparent when viewed by MPlayer. This means that you can even have shaped windows if your X server has the XShape extension.

D.1.3 Skin components

Skins are quite free-format (unlike the fixed-format skins of Winamp/XMMS, for example), so it is up to you to create something great.

Currently there are three windows to be decorated: the main window, the subwindow, the playbar, and the skin menu (which can be activated by a right click).

The main window and/or the playbar is where you can control MPlayer. The background of the window is an image. Various items can (and must) be placed in the window: buttons, potmeters (sliders) and labels. For every item, you must specify its position and size.

A button has three states (pressed, released, disabled), thus its image must be divided into three parts vertically. See the button item for details.

A potmeter (mainly used for the seek bar and volume/balance control) can have any number of phases by dividing its image into different parts below each other. See hpotmeter and potmeter for details.

Labels are a bit special: The characters needed to draw them are taken from an image file, and the characters in the image are described by a font description file. The latter is a plain text file which specifies the x,y position and size of each character in the image (the image file and its font description file form a font together). See dlabel and slabel for details.

Note: all images can have full transparency as described in the section about image formats. If the X server doesn't support the XShape extension, the parts marked transparent will be black. If you'd like to use this feature, the width of the main window's background image must be dividable by 8.
The subwindow is where the movie appears. It can display a specified image if there is no movie loaded (it is quite boring to have an empty window :-)) Note: transparency is not allowed here.
The skin menu is just a way to control MPlayer by means of menu entries. Two images are required for the menu: one of them is the base image that shows the menu in its normal state, the other one is used to display the selected entries. When you pop up the menu, the first image is shown. If you move the mouse over the menu entries, the currently selected entry is copied from the second image over the menu entry below the mouse pointer (the second image is never shown as a whole).

A menu entry is defined by its position and size in the image (see the section about the skin menu for details).

There is an important thing not mentioned yet: For buttons, potmeters and menu entries to work, MPlayer must know what to do if they are clicked. This is done by messages (events). For these items you must define the messages to be generated when they are clicked.

D.1.4 Files

You need the following files to build a skin:

The configuration file named skin tells MPlayer how to put different parts of the skin together and what to do if you click somewhere in the window.
The background image for the main window.
Images for the items in the main window (including one or more font description files needed to draw labels).
The image to be displayed in the subwindow (optional).
Two images for the skin menu (they are needed only if you want to create a menu).

With the exception of the skin configuration file, you can name the other files whatever you want (but note that font description files must have a .fnt extension).

D.2 The skin file

As mentioned above, this is the skin configuration file. It is line oriented; comment lines start with a ';' character at the beginning of the line (only spaces and tabs are allowed before the ';').

The file is made up of sections. Each section describes the skin for an application and has the following form:

section = section name
.
.
.
end

Currently there is only one application, so you need only one section: its name is movieplayer.

Within this section each window is described by a block of the following form:

window = window name
.
.
.
end

where window name can be one of these strings:

main - for the main window
sub - for the subwindow
menu - for the skin menu
playbar - playbar

(The sub and menu blocks are optional - you do not need to create a menu or decorate the subwindow.)

Within a window block, you can define each item for the window by a line in this form:

item = parameter: Where item is a string that identifies the type of the GUI item, parameter is a numeric or textual value (or a list of values separated by commas).

Putting the above together, the whole file looks something like this:

section = movieplayer
  window = main
  ; ... items for main window ...
  end
  
  window = sub
  ; ... items for subwindow ...
  end
  
  window = menu
  ; ... items for menu ...
  end

  window = playbar
  ; ... items for playbar ...
  end
end

The name of an image file must be given without leading directories - images are searched for in the Skin directory. You may (but you need not) specify the extension of the file. If the file does not exist, MPlayer tries to load the file <filename>.<ext>, where png and PNG are tried for <ext> (in this order). The first matching file will be used.

Finally some words about positioning. The main window and the subwindow can be placed in the different corners of the screen by giving X and Y coordinates. 0 is top or left, -1 is center and -2 is right or bottom, as shown in this illustration:


(0, 0)----(-1, 0)----(-2, 0)
  |          |          |
  |          |          |
(0,-1)----(-1,-1)----(-2,-1)
  |          |          |
  |          |          |
(0,-2)----(-1,-2)----(-2,-2)

Here is an example to make this clear. Suppose that you have an image called main.png that you use for the main window:

    base = main, -1, -1

MPlayer tries to load main, main.png, main.PNG files.

D.2.1 Main window and playbar

Below is the list of entries that can be used in the 'window = main' . . . 'end', and the 'window = playbar' . . 'end' blocks.

base = image, X, Y

Lets you specify the background image to be used for the main window. The window will appear at the given X,Y position on the screen The window will have the size of the image.

Note: These coordinates do not currently work for the display window.
Warning: Transparent regions in the image (colored #FF00FF) appear black on X servers without the XShape extension. The image's width must be dividable by 8.

button = image, X, Y, width, height, message

Place a button of width * height size at position X,Y. The specified message is generated when the button is clicked. The image given by image must have three parts below each other (according to the possible states of the button), like this:

+------------+
|  pressed   |
+------------+
|  released  |
+------------+
|  disabled  |
+------------+

decoration = enable|disable

Enable or disable window manager decoration of the main window. Default is disable.

Note: This doesn't work for the display window, there is no need to.

hpotmeter = button, bwidth, bheight, phases, numphases, default, X, Y, width, height, message vpotmeter = button, bwidth, bheight, phases, numphases, default, X, Y, width, height, message

Place a horizontal (hpotmeter) or vertical (vpotmeter) potmeter of width * height size at position X,Y. The image can be divided into different parts for the different phases of the potmeter (for example, you can have a pot for volume control that turns from green to red while its value changes from the minimum to the maximum.). hpotmeter can have a button that can be dragged horizontally.

The parameters are:

button - the image to be used for the button (must have three parts below each other, like in case of button)
bwidth, bheight - size of the button
phases - The image to be used for the different phases of the hpotmeter. A special value of NULL can be used if you want no such image. The image must be divided into numphasesparts vertically like this:
```
+------------+
|  phase #1  |
+------------+
|  phase #2  |
+------------+
     ...
+------------+
|  phase #n  |
+------------+
```
numphases - number of phases stored in the phases image
default - default value for hpotmeter (in the range 0 to 100)
X, Y - position for the hpotmeter
width, height - width and height of the hpotmeter
message - the message to be generated when the value of hpotmeter is changed

potmeter = phases, numphases, default, X, Y, width, height, message

A hpotmeter without a button. (I guess it is meant to be turned around, but it reacts to horizontal dragging only.) For the description of the parameters see hpotmeter. phases can be NULL, but it is quite useless, since you cannot see where the potmeter is set.

font = fontfile, fontid

Defines a font. fontfile is the name of a font description file with a .fnt extension (do not specify the extension here). fontid is used to refer to the font (see dlabel and slabel). Up to 25 fonts can be defined.

slabel = X, Y, fontid, "text"

Place a static label at the position X,Y. text is displayed using the font identified by fontid. The text is just a raw string ($x variables do not work) that must be enclosed between double quotes (but the " character cannot be part of the text). The label is displayed using the font identified by fontid.

dlabel = X, Y, length, align, fontid, "text"

Place a dynamic label at the position X,Y. The label is called dynamic because its text is refreshed periodically. The maximum length of the label is given by length (its height is the height of a character). If the text to be displayed is wider than that, it will be scrolled, otherwise it is aligned within the specified space by the value of the align parameter: 0 is for right, 1 is for center, 2 is for left.
The text to be displayed is given by text: It must be written between double quotes (but the " character cannot be part of the text). The label is displayed using the font identified by fontid. You can use the following variables in the text:

Variable	Meaning
`$1`	play time in hh:mm:ss format
`$2`	play time in mmmm:ss format
`$3`	play time in hh format (hours)
`$4`	play time in mm format (minutes)
`$5`	play time in ss format (seconds)
`$6`	movie length in hh:mm:ss format
`$7`	movie length in mmmm:ss format
`$8`	play time in h:mm:ss format
`$v`	volume in xxx.xx% format
`$V`	volume in xxx.x format
`$b`	balance in xxx.xx% format
`$B`	balance in xxx.x format
`$$`	the `$` character
`$a`	a character according to the audio type (none: `n`, mono: `m`, stereo: `t`)
`$t`	track number (in playlist)
`$o`	filename
`$f`	filename in lower case
`$F`	filename in upper case
`$T`	a character according to the stream type (file: `f`, Video CD: `v`, DVD: `d`, URL: `u`)
`$p`	the "p" character (if a movie is playing and the font has the "p" character)
`$s`	the "s" character (if the movie is stopped and the font has the "s" character)
`$e`	the "e" character (if playback is paused and the font has the "e" character)
`$x`	movie width
`$y`	movie height
`$C`	name of the codec used

Note: The $a, $T, $p, $sand $e variables all return characters that should be displayed as special symbols (for example, "e" is for the pause symbol that usually looks something like ||). You should have a font for normal characters and a different font for symbols. See the section about symbols for more information.

D.2.2 Subwindow

The following entries can be used in the 'window = sub' . . . 'end' block.

base = image, X, Y, width, height: The image to be displayed in the window. The window will appear at the given X,Y position on the screen (0,0 is the top left corner). You can specify -1 for center and -2 for right (X) and bottom (Y). The window will be as large as the image. width and height denote the size of the window; they are optional (if they are missing, the window is the same size as the image).
background = R, G, B: Lets you set the background color. It is useful if the image is smaller than the window. R, G and B specifies the red, green and blue component of the color (each of them is a decimal number from 0 to 255).

D.2.3 Skin menu

As mentioned earlier, the menu is displayed using two images. Normal menu entries are taken from the image specified by the base item, while the currently selected entry is taken from the image specified by the selected item. You must define the position and size of each menu entry through the menu item.

These are the entries that can be used in the 'window = menu' . . . 'end' block.

base = image: The image for normal menu entries.
selected = image: The image showing the menu with all entries selected.
menu = X, Y, width, height, message: Defines the X,Y position and the size of a menu entry in the image. message is the message to be generated when the mouse button is released over the entry.

D.3 Fonts

As mentioned in the section about the parts of a skin, a font is defined by an image and a description file. You can place the characters anywhere in the image, but make sure that their position and size is given in the description file exactly.

The font description file (with .fnt extension) can have comment lines starting with ';'. The file must have a line in the form

image = image: Where image is the name of the image file to be used for the font (you do not have to specify the extension).
"char" = X, Y, width, height: Here X and Y specify the position of the char character in the image (0,0 is the upper left corner). width and height are the dimensions of the character in pixels.

This example defines the A, B, C characters using font.png.

; Can be "font" instead of "font.png".
image = font.png

; Three characters are enough for demonstration purposes :-)
"A" =  0,0, 7,13
"B" =  7,0, 7,13
"C" = 14,0, 7,13

D.3.1 Symbols

Some characters have special meanings when returned by some of the variables used in dlabel. These characters are meant to be shown as symbols so that things like a nice DVD logo can be displayed instead of the character 'd' for a DVD stream.

The following table lists all the characters that can be used to display symbols (and thus require a different font).

Character	Symbol
`p`	play
`s`	stop
`e`	pause
`n`	no sound
`m`	mono sound
`t`	stereo sound
`f`	stream is a file
`v`	stream is a Video CD
`d`	stream is a DVD
`u`	stream is a URL

D.4 GUI messages

These are the messages that can be generated by buttons, potmeters and menu entries.

Note: Some of the messages might not work as expected (or not work at all). As you know, the GUI is under development.

Playback control:

evNext

Jump to next track in the playlist.

evPause

Pause playing.

evPauseSwitchToPlay

Forms a switch together with evPlaySwitchToPause. They can be used to have a common play/pause button. Both messages should be assigned to buttons displayed at the very same position in the window. This message pauses playing and the image for the evPlaySwitchToPause button is displayed (to indicate that the button can be pressed to continue playing).

evPlay

Start playing.

evPlaySwitchToPause

The opposite of evPauseSwitchToPlay. This message starts playing and the image for the evPauseSwitchToPlay button is displayed (to indicate that the button can be pressed to pause playing).

evPrev

Jump to previous track in the playlist.

evStop

Stop playing.

Seeking:

evBackward10sec

evBackward1min

evBackward10min

Seek backward 10 seconds / 1 minute / 10 minutes.

evForward10sec

evForward1min

evForward10min

Seek forward 10 seconds / 1 minute / 10 minutes.

evSetMoviePosition

Seek to position (can be used by a potmeter; the relative value (0-100%) of the potmeter is used).

Video control:

evDoubleSize

Set the movie window to double size.

evFullScreen

Switch fullscreen mode on/off.

evNormalSize

Set the movie window to its normal size.

Audio control:

evDecAudioBufDelay

Decrease audio buffer delay.

evDecBalance

Decrease balance.

evDecVolume

Decrease volume.

evIncAudioBufDelay

Increase audio buffer delay.

evIncBalance

Increase balance.

evIncVolume

Increase volume.

evMute

Mute/unmute the sound.

evSetBalance

Set balance (can be used by a potmeter; the relative value (0-100%) of the potmeter is used).

evSetVolume

Set volume (can be used by a potmeter; the relative value (0-100%) of the potmeter is used).

Miscellaneous:

evAbout

Open the about window.

evDropSubtitle

Disables the currently used subtitle.

evEqualizer

Turn the equalizer on/off.

evExit

Quit the program.

evIconify

Iconify the window.

evLoad

Load a file (by opening a file browser window, where you can choose a file).

evLoadPlay

Does the same as evLoad, but it automatically starts playing after the file is loaded.

evLoadSubtitle

Loads a subtitle file (with the fileselector)

evLoadAudioFile

Loads an audio file (with the fileselector)

evNone

Empty message, it has no effect (except maybe in CVS versions :-)).

evPlayList

Open/close the playlist window.

evPlayDVD

Tries to open the disc in the given DVD-ROM drive.

evPlayVCD

Tries to open the disc in the given CD-ROM drive.

evPreferences

Open the preferences window.

evSetAspect

Sets displayed image aspect.

evSetURL

Displays the URL dialog window.

evSkinBrowser

Open the skin browser window.