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How to calculate SHA-256 of a bitmap image in android studio?

I have already tried converting image into byte array and then find its message digest but it gives a completely different answer than what I find using online SHA-256 converters. I know how to calculate SHA-256 for a string but I am unable to calculate SHA-256 for a bitmap image.

Nirojan Selvanathan
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Thatz'it
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  • Please share your code which you have tried – Romil Patel Jun 24 '19 at 04:20
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    What have you tried so far? Please [edit] your question to include a [mcve] of your code, including any implementations you might have already (for example, calculating a SHA256 from a string), and anything you've tried so far to get this working yourself. – Hoppeduppeanut Jun 24 '19 at 04:21

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Try this 

fun sampleHashFile(bitmap: Bitmap): String {
    val baos = ByteArrayOutputStream()
    bitmap.compress(Bitmap.CompressFormat.JPEG, 50, baos)
    val bb = baos.toByteArray()

    val bc = MessageDigest.getInstance("SHA-256").digest(bb)
    return BigInteger(1, bc).toString(16)
}**strong text**
ylinkz
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