airatlovesmusic / Kompressor

Friendly lightweight lib for image compressions in Android. Without context and file system. Based on input and output streams

Kompressor

Since the new Android 11 is coming soon, we should think about refactoring and deprecation methods. When Android 10 was released, Google hinted at Android 11 requiring all apps to use Scoped Storage, regardless of targetSdkVersion. That means we should migrate to Scoped Storage as soon as possible.

Unfortunately, most of compression libs still work with filesystem and don't support contentUris. It can cause problems with new SDK versions, no matter if you have a android:requestLegacyExternalStorage=”true" in manifest or not. Remember, contentUris can point not only to local files, but also to "virtual" files on the cloud. Therefore, this lib is built on input and output streams and it doesn't work with files.

Gradle

dependencies {
    implementation 'com.github.airatlovesmusic:Kompressor:0.2.0'
}

Let's compress something!

val inputStream = context.contentResolver.openInputStream(contentUri)
val compressedData = imageCompressor.compress(
        inputStream = context.contentResolver.openInputStream(contentUri),
        format = Bitmap.CompressFormat.JPEG,
        quality = 70
)
val compressedBitmap = BitmapFactory.decodeStream(compressedData)

Do whatever you want with received OutputStream, for example you can make Retrofit RequestBody with bytes from stream.

Let's compress something, but with configuration!

val inputStream = context.contentResolver.openInputStream(contentUri)
val compressedData = imageCompressor.compress(
        inputStream = context.contentResolver.openInputStream(contentUri),
        format = Bitmap.CompressFormat.PNG,
        quality = 70,
        steps = resolutionCompression(outHeight = 720, outWidth = 1024) + sizeCompression(FILE_MAX_SIZE)
)
val compressedBitmap = BitmapFactory.decodeStream(compressedData)

This library has multiple compression constraints you can combine:

• resolutionCompression (set up required height and width of result image),
• sizeCompression (set up max file size of image),
• rotationCompression (rotate image)

Let's compress something, but with custom configuration!

val inputStream = context.contentResolver.openInputStream(contentUri)
val compressedData = imageCompressor.compress(
        inputStream = context.contentResolver.openInputStream(contentUri),
        format = Bitmap.CompressFormat.PNG,
        quality = 70,
        steps = resolutionCompression(outHeight = 720, outWidth = 1024) + { bm: Bitmap -> bm }
)
val compressedBitmap = BitmapFactory.decodeStream(compressedData)

You can also easily add your own custom compression steps by passing function which takes Bitmap and returns Bitmap.

What's next

• More friendly API
• Error handling
• Video compression