Aapt error failed to read png signature file does not start with png signature

Gradle build failing with this error:

Error:C:UsersRoman.gradlecachestransforms-1files-1.1appcompat-v7-26.0.2.aarbab547c3f1b8061ef9426f524a823a15resdrawable-xhdpi-v4abc_btn_switch_to_on_mtrl_00001.9.png failed to read PNG signature: file does not start with PNG signature

Error:java.lang.RuntimeException: java.lang.RuntimeException: com.android.builder.internal.aapt.AaptException: AAPT2 compile failed:
Error:Execution failed for task ':app:mergeDebugResources'.
Error: java.lang.RuntimeException: java.lang.RuntimeException: com.android.builder.internal.aapt.AaptException: AAPT2 compile failed:
aapt2 compile --legacy -o C:devworkspaceandroid2MatrixCalculatorappbuildintermediatesresmergeddebug C:UsersRoman.gradlecachestransforms-1files-1.1appcompat-v7-26.0.2.aarbab547c3f1b8061ef9426f524a823a15resdrawable-xhdpi-v4abc_btn_switch_to_on_mtrl_00001.9.png
Issues:
 - ERROR: C:UsersRoman.gradlecachestransforms-1files-1.1appcompat-v7-26.0.2.aarbab547c3f1b8061ef9426f524a823a15resdrawable-xhdpi-v4abc_btn_switch_to_on_mtrl_00001.9.png failed to read PNG signature: file does not start with PNG signature

Some basic things i’ve tried to solve this issue:

1. Invalidate caches/restart
2. Deleting gradle folder

For instance, you have ic_logo.png but it’s actually a JPG image.
You should rename it back to ic_logo.jpg and use something like Photoshop to convert the image to PNG format.

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







 buildTypes {
        debug {
            signingConfig signingConfigs.debug
        }
        release {
            crunchPngs false // or true

            lintOptions {
                checkReleaseBuilds false
                abortOnError false
            }
            minifyEnabled false
            proguardFiles getDefaultProguardFile('proguard-android.txt'), 'proguard-rules.pro'
        }
    }

Steps

1. In build.gradle

aaptOptions {
    cruncherEnabled = false
}

1. Delete content inside C:Users.gradlecaches (or ~/.gradle/caches for Mac and Linux)
2. Restart Android Studio

Failed to read PNG signature — Just put 1 line in your build.gradle

 buildTypes {
    release {
        minifyEnabled true
        shrinkResources true
        crunchPngs false  // Paste this line
        proguardFiles getDefaultProguardFile('proguard-android-optimize.txt'), 'proguard-rules.pro'
    }
}

Creating the .apk of an application all the resources are analyzed, if some resource has an incorrect format or is corrup you will get the message:

.png failed to read PNG signature: file does not start with PNG
signature

Be sure to have the correct resources, you can check it by opening your file.

This occurs due to the incorrect extension given to the image. For example, the image is jpg and the extension given is png.

Solutions:

1. Add { cruncherEnabled = false } in build.gradle
2. Convert the image into png rather than just changing the extension.

I had the same issue, solved by converting the images to webP from Android studio
right-click on the image -> tap on Convert to WebP

the conversion will handle file formating and also reduce the size of the PNG

Solution

In my case also there was a jpg file instead of png, so I changed my extension and solve my problem.

If you are using an online platform to generate App Icon(launcher_icon), then use PNG Format or First convert JPEG to PNG and then used APP ICON GENERATOR

You might have used a JPEG file or some other image file format.

Use PNG images to solve the error.

Drawable directory can only have png type of images.

If you don’t have any transparent pixels, then renaming the file to .jpg worked for me.

i have same error for slow i do some step:

1. open abc_btn_switch_to_on_mtrl_00001.9.png (Image)file in paint
2. now select png and save as and re-save in drawable and overweight in with old images and its work

For a quick fix ,Make shrinkResources to false instead of true in app.gradle
Hope this will help.
if Not then also add this aaptOptions { cruncherEnabled = false }

This is a result of wrong file type indeed and can be fixed by saving the files in correct format.

I ran into this issue with PhoneGap Build and wanted to leave my 2 cents for any other PhoneGap / Cordova user who might also run into this.

My problem was that I upgraded my old PhoneGap 6.x to 8.0 and it seems behaviour of the default splash has changed. It used to require jpg as a default splash, but on 8.0 it results in this error on production builds.

This worked before:

<splash src="www/splash.jpg" />

Now you have 2 options. Replace the default splash with png like this:

<splash src="www/res/screen/android/screen-xhdpi-portrait.png" />

Other option is to remove default splash entirely.

I’m not sure if it’s a valid solution, but deleting only the file mentioned in the error message helped. While deleting the folder, containing it didn’t.

I was able to fix it permanently.

I created a new blank expo project, then I added a new app icon (correct png format), then I ejected from expo.

I then copied the mipmap-* folders from the blank project to my real project. It all worked perfectly.

I’ve had the same issue. To solve it just restart your Android Studio and build the gradle file again.

You can add code in node_modules/react-native/react.gradle. After doFirst

doLast {
def moveFunc = { resSuffix ->
File originalDir = file("$buildDir/generated/res/react/release/${resSuffix}");
if (originalDir.exists()) {
File destDir = file("$buildDir/../src/main/res/${resSuffix}");
ant.move(file: originalDir, tofile: destDir);
}
}
moveFunc.curry("drawable-ldpi").call()
moveFunc.curry("drawable-mdpi").call()
moveFunc.curry("drawable-hdpi").call()
moveFunc.curry("drawable-xhdpi").call()
moveFunc.curry("drawable-xxhdpi").call()
moveFunc.curry("drawable-xxxhdpi").call()
moveFunc.curry("raw").call()
}

check it if it not fix issue after remove drawable folder
github enter link description here

You can open the images with windows win10 ‘Paint’,
then you can save as .png and overrite it,
It will solve the problem

Comments Section

The file abc_btn_switch_to_on_mtrl_00001.9.png is corrupt, and is not a valid PNG file.

«Deleting gradle folder» — which specific folder did you delete?

@CommonsWare the one at C:UsersRoman.gradlecaches and the one in the project

You don’t say if this is a new resource or an existing one that is now showing this symptom. This is an important detail that should be in the body of the question itself.

Try getting the support lib referenced from developer.android.com/topic/libraries/support-library/… instead of your local SDK. You can force it to grab a different version instead of 26.0.2 via dependencies and see if the problem goes away. Looks like your local SDK is corrupt if blowing away the IDE cache is still a problem.

This was our root cause as well — graphic designer accidentally saved a JPEG with a .PNG extension.

but this image is in android libraries and not for project!

@MHSFisher If you can report the developers of that library, do so, otherwise, see if you can replace the image using a standard one of your own.

Just followed Step 1 and problem solved, Thx @DiegoVenâncio, Upvoted for saving my day.

This was the problem in our project as well. Renamed the file extensions to .jpg and then used Paint 3D to convert the image extensions to .png

This fixed my issue. Thanks.

This worked for me, the error is very confusing b/c it makes it seem like your files aren’t pngs when they are. In truth, it’s crunching them that’s the problem. Since I can crunch other things and only pngs are the issue, I prefer your solution to the cruncherEnabled version.

Related Topics
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android-gradle-plugin

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References
46177560/failed-to-read-png-signature-file-does-not-start-with-png-signature