README.md
1# Steps to regenerate background text images under res-*dpi/images/
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31. Build the recovery_l10n app:
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5 cd bootable/recovery && mma -j32
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72. Install the app on the device (or emulator) with the intended dpi.
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9 * For example, we can use Nexus 5 to generate the text images under
10 res-xxhdpi.
11 * We can set up the maximum width of the final png image in res/layout/main.xml
12 Currently, the image width is 1200px for xxxhdpi, 900px for xxhdpi and
13 480px for xhdpi/hdpi/mdpi.
14 * When using the emulator, make sure the NDK version matches the current
15 repository. Otherwise, the app may not work properly.
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17 adb install $PATH_TO_APP
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193. Run the app, select the string to translate and press the 'go' button.
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214. After the app goes through the strings for all locales, pull the output png
22 file from the device.
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24 adb root && adb pull /data/data/com.android.recovery_l10n/files/text-out.png
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265. Compress the output file put it under the corresponding directory.
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28 * "pngcrush -c 0 ..." converts "text-out.png" into a 1-channel image,
29 which is accepted by Recovery. This also compresses the image file by
30 ~60%.
31 * zopflipng could further compress the png files by ~10%, more details
32 in https://github.com/google/zopfli/blob/master/README.zopflipng
33 * If you're using other png compression tools, make sure the final text
34 image works by running graphic tests under the recovery mode.
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36 pngcrush -c 0 text-out.png $OUTPUT_PNG
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