Disable Android resource / image / PNG optimization

Question

How do I prevent the Android "build process" from optimizing .png images?

I have an Android project with the following res directories:

- /res/
- /res/drawable
- /res/drawable-hdpi
- /res/drawable-hdpi-v5
- /res/drawable-ldpi
- /res/drawable-ldpi-v5
- /res/drawable-mdpi
- /res/drawable-mdpi-v5

These directories contain many .png files. I optimize PNG sizes with PNGOUTWin, and the overall size is reduced by more than 20%. When I build the .apk file, the images are "optimized" by the build process and the overall size is now 10% above the initial size, or 30% above my/PNGOUTWin optimized size.

My goal is to reduce the .apk size, even if it will affect the final performance, memory requirements, etc. How do I prevent the "build process" from optimizing .png images?

I'm targeting Android 2.2 and above.

P.S.: I am currently building my Android project from Eclipse, but I will switch to the automated build later (Ant?).

Note about JPG images: JPG will not work, because they do not have transparency.

ChrisG · Answer 1 · 2015-04-23T20:24:58.780

39

Finally there is an official way to disable the PNG cruncher with Gradle which hasn't been mentioned here yet:

Edit main build.gradle to require gradle version 1.1.3 (or newer):

buildscript {  
    repositories {  
        mavenCentral()  
    }  
    dependencies {  
        classpath 'com.android.tools.build:gradle:1.1.3'  
    }  
}

In the individual apps's build.gradle, section android {}, insert:
```
aaptOptions {  
    cruncherEnabled = false  
}  
```

Reference: https://code.google.com/p/android/issues/detail?id=65335

edited Apr 23 '15 at 20:24

answered Apr 23 '15 at 20:16

ChrisG

391
3
7

1

Wow this just cut about 1 min of build time for my debug builds – Patrick Nov 01 '15 at 08:38
2

Is it possible to do it only for debug build? Maybe it can reduce build time – android developer Feb 14 '17 at 11:29

score 22 · Answer 2 · answered Jul 01 '17 at 04:56

22

Specifying PNG crunching is now a BuildType property and is disabled by default on debug builds:

android {
    …
    buildTypes {
        release {
            crunchPngs false // or true
        }
    }
}

Note: It's available from Android Studio 3.0 Canary 5 .

answered Jul 01 '17 at 04:56

pRaNaY

24,642
24
96
146

1

Thank you. After a lot of time wasted your's only answer helped me. – Taras Vovkovych Dec 07 '17 at 09:26
Glade to helps you. Thanks :) – pRaNaY Dec 07 '17 at 10:02

score 2 · Accepted Answer · edited Jan 20 '18 at 00:35

2

As mentioned in the Android documentation: http://developer.android.com/guide/topics/graphics/2d-graphics.html#drawables

Note: Image resources placed in res/drawable/ may be automatically optimized with lossless image compression by the aapt tool during the build process. For example, a true-color PNG that does not require more than 256 colors may be converted to an 8-bit PNG with a color palette. This will result in an image of equal quality but which requires less memory. So be aware that the image binaries placed in this directory can change during the build.

So if you want to reduce the size of your application you should either reduce the color-depth of your PNG files (this helps a lot) or switch to .JPG files wherever possible.

edited Jan 20 '18 at 00:35

Peter Mortensen

30,738
21
105
131

answered Oct 17 '12 at 09:12

Vinayak Bevinakatti

40,205
25
108
139

1

8-bit PNG files with alpha channel -- pretty shadows, many colors, size 200x200 looks ugly. Not perfect. Currently using Photoshop + Web Image Guru + PNGOUTWin postprocess. – Maris B. Oct 17 '12 at 10:11
Yes you cannot have gradient effects, shadow effects etc.. as in PNG in JPG, so only I mentioned use jpg wherever possible. – Vinayak Bevinakatti Oct 17 '12 at 11:53
Accepting your answer because indeed, images that looks nice in 8-bit PNG format are not optimized by the "build" process. However I ended up using Ant + 7-zip + original PNGs. – Maris B. Oct 20 '12 at 06:52
6

this answer does not answer the question at all, I don't understand how it got accepted – Display Name Aug 24 '15 at 09:48

score 2 · Answer 4 · edited Jan 20 '18 at 00:36

2

Android Studio: Since Gradle Android plugin 1.0.0:

android {
...
  aaptOptions {
    useNewCruncher false
  }
....
}

Eclipse: Override the crunch task writing this in your build.xml:

<target name="-crunch">
   <echo message="This will skip PNG optimization"/>
</target>

edited Jan 20 '18 at 00:36

Peter Mortensen

30,738
21
105
131

answered Mar 08 '15 at 17:03

Yair Kukielka

10,686
1
38
46

I confirm that your Eclipse example also works with command line Ant-based workflow; by enclosing the code in `` tag, and place them in `custom_rules.xml`, placed on project's root directory-- I originally thought the override wouldn't work (since PNGs won't be copied to `bin/res` folder), but it turned out that the toolchain would just use PNGs from original `res` folder in this case. – xwindows -on strike- Sep 04 '19 at 06:59

score 2 · Answer 5 · answered May 11 '20 at 04:35

 buildTypes {
        release {
            crunchPngs false // or true
        }
    }

add above the line on android block in

in ionic/Cordova project : root_folder_Of_App/platforms/android/app/build.gradle

in Android project: app/build.gradle

For More Information Visit: https://androidstudio.googleblog.com/2017/06/android-studio-30-canary-5-is-now.html

Huh X0015 · Answer 6 · 2017-05-08T23:19:08.730

Google recently introduced a new PNG processor in aapt 0.9.1 in the Android SDK Build Tools that fixes this issue of increased PNG sizes after aapt optimization.

With this update, it is now possible for Android Studio & Gradle to switch between the PNG processors with the following change in your build.gradle configuration file:

android {
    ..
    ..

    aaptOptions.useAaptPngCruncher = false
}

By adding this line, aapt uses the new PNG processor in which it checks to see if the "optimized" PNG files are smaller than the original PNG files. I was able to reduce 4.8 MB in my compiled APK and have not encountered any bugs/issues with the new build configuration.

UPDATE: This has been deprecated in later versions of Android Studio. Please refer to the answer provided by ChrisG.

I think thats obselete as of now, use the answer by @ChrisG – Patrick Nov 01 '15 at 08:30 — Patrick, Nov 01 '15 at 08:30

Disable Android resource / image / PNG optimization

6 Answers6

Linked