1 # bootanimation format 2 3 ## zipfile paths 4 5 The system selects a boot animation zipfile from the following locations, in order: 6 7 /system/media/bootanimation-encrypted.zip (if getprop("vold.decrypt") = '1') 8 /system/media/bootanimation.zip 9 /oem/media/bootanimation.zip 10 11 ## zipfile layout 12 13 The `bootanimation.zip` archive file includes: 14 15 desc.txt - a text file 16 part0 \ 17 part1 \ directories full of PNG frames 18 ... / 19 partN / 20 21 ## desc.txt format 22 23 The first line defines the general parameters of the animation: 24 25 WIDTH HEIGHT FPS 26 27 * **WIDTH:** animation width (pixels) 28 * **HEIGHT:** animation height (pixels) 29 * **FPS:** frames per second, e.g. 60 30 31 It is followed by a number of rows of the form: 32 33 TYPE COUNT PAUSE PATH [#RGBHEX [CLOCK1 [CLOCK2]]] 34 35 * **TYPE:** a single char indicating what type of animation segment this is: 36 + `p` -- this part will play unless interrupted by the end of the boot 37 + `c` -- this part will play to completion, no matter what 38 * **COUNT:** how many times to play the animation, or 0 to loop forever until boot is complete 39 * **PAUSE:** number of FRAMES to delay after this part ends 40 * **PATH:** directory in which to find the frames for this part (e.g. `part0`) 41 * **RGBHEX:** _(OPTIONAL)_ a background color, specified as `#RRGGBB` 42 * **CLOCK1, CLOCK2:** _(OPTIONAL)_ the coordinates at which to draw the current time (for watches): 43 + If only `CLOCK1` is provided it is the y-coordinate of the clock and the x-coordinate 44 defaults to `c` 45 + If both `CLOCK1` and `CLOCK2` are provided then `CLOCK1` is the x-coordinate and `CLOCK2` is 46 the y-coodinate 47 + Values can be either a positive integer, a negative integer, or `c` 48 - `c` -- will centre the text 49 - `n` -- will position the text n pixels from the start; left edge for x-axis, bottom edge 50 for y-axis 51 - `-n` -- will position the text n pixels from the end; right edge for x-axis, top edge 52 for y-axis 53 - Examples: 54 * `-24` or `c -24` will position the text 24 pixels from the top of the screen, 55 centred horizontally 56 * `16 c` will position the text 16 pixels from the left of the screen, centred 57 vertically 58 * `-32 32` will position the text such that the bottom right corner is 32 pixels above 59 and 32 pixels left of the edges of the screen 60 61 There is also a special TYPE, `$SYSTEM`, that loads `/system/media/bootanimation.zip` 62 and plays that. 63 64 ## clock_font.png 65 66 The file used to draw the time on top of the boot animation. The font format is as follows: 67 * The file specifies glyphs for the ascii characters 32-127 (0x20-0x7F), both regular weight and 68 bold weight. 69 * The image is divided into a grid of characters 70 * There are 16 columns and 6 rows 71 * Each row is divided in half: regular weight glyphs on the top half, bold glyphs on the bottom 72 * For a NxM image each character glyph will be N/16 pixels wide and M/(12*2) pixels high 73 74 ## loading and playing frames 75 76 Each part is scanned and loaded directly from the zip archive. Within a part directory, every file 77 (except `trim.txt` and `audio.wav`; see next sections) is expected to be a PNG file that represents 78 one frame in that part (at the specified resolution). For this reason it is important that frames be 79 named sequentially (e.g. `part000.png`, `part001.png`, ...) and added to the zip archive in that 80 order. 81 82 ## trim.txt 83 84 To save on memory, textures may be trimmed by their background color. trim.txt sequentially lists 85 the trim output for each frame in its directory, so the frames may be properly positioned. 86 Output should be of the form: `WxH+X+Y`. Example: 87 88 713x165+388+914 89 708x152+388+912 90 707x139+388+911 91 649x92+388+910 92 93 If the file is not present, each frame is assumed to be the same size as the animation. 94 95 ## audio.wav 96 97 Each part may optionally play a `wav` sample when it starts. To enable this, add a file 98 with the name `audio.wav` in the part directory. 99 100 ## exiting 101 102 The system will end the boot animation (first completing any incomplete or even entirely unplayed 103 parts that are of type `c`) when the system is finished booting. (This is accomplished by setting 104 the system property `service.bootanim.exit` to a nonzero string.) 105 106 ## protips 107 108 ### PNG compression 109 110 Use `zopflipng` if you have it, otherwise `pngcrush` will do. e.g.: 111 112 for fn in *.png ; do 113 zopflipng -m ${fn}s ${fn}s.new && mv -f ${fn}s.new ${fn} 114 # or: pngcrush -q .... 115 done 116 117 Some animations benefit from being reduced to 256 colors: 118 119 pngquant --force --ext .png *.png 120 # alternatively: mogrify -colors 256 anim-tmp/*/*.png 121 122 ### creating the ZIP archive 123 124 cd <path-to-pieces> 125 zip -0qry -i \*.txt \*.png \*.wav @ ../bootanimation.zip *.txt part* 126 127 Note that the ZIP archive is not actually compressed! The PNG files are already as compressed 128 as they can reasonably get, and there is unlikely to be any redundancy between files. 129
