Android UI How to - Manipulate Image

• Back to ImageView  ↑

The following code shows how to Manipulate Image.

Code revised from
Android Recipes:A Problem-Solution Approach
http://www.apress.com/9781430234135
ISBN13: 978-1-4302-3413-5

Example

Main layout xml file

<?xml version="1.0" encoding="utf-8"?>
<TableLayout xmlns:android="http://schemas.android.com/apk/res/android"
    android:layout_width="match_parent"
    android:layout_height="match_parent"
    android:stretchColumns="*">
    <TableRow>
        <ImageView
            android:id="@+id/image_normal"
            android:layout_weight="1"
            android:layout_margin="5dp"
            android:scaleType="fitCenter" />
        <ImageView
            android:id="@+id/image_blurred"
            android:layout_weight="1"
            android:layout_margin="5dp"
            android:scaleType="fitCenter" />
    </TableRow>

    <TableRow>
        <ImageView
            android:id="@+id/image_greyscale"
            android:layout_weight="1"
            android:layout_margin="5dp"
            android:scaleType="fitCenter" />
        <ImageView
            android:id="@+id/image_sharpen"
            android:layout_weight="1"
            android:layout_margin="5dp"
            android:scaleType="fitCenter" />
    </TableRow>

    <TableRow>
        <ImageView
            android:id="@+id/image_edge"
            android:layout_weight="1"
            android:layout_margin="5dp"
            android:scaleType="fitCenter" />
        <ImageView
            android:id="@+id/image_emboss"
            android:layout_weight="1"
            android:layout_margin="5dp"
            android:scaleType="fitCenter" />
    </TableRow>

</TableLayout>

Main Activity Java code

package com.java2s.myapplication3.app;
/*from w  w w .j  av a 2s . c  o  m*/
import android.app.Activity;
import android.graphics.Bitmap;
import android.graphics.BitmapFactory;
import android.os.Bundle;
import android.renderscript.Allocation;
import android.renderscript.Element;
import android.renderscript.RenderScript;
import android.renderscript.ScriptIntrinsicBlur;
import android.renderscript.ScriptIntrinsicColorMatrix;
import android.renderscript.ScriptIntrinsicConvolve3x3;
import android.widget.ImageView;

public class MainActivity extends Activity {

    private enum ConvolutionFilter {
        SHARPEN, LIGHTEN, DARKEN, EDGE_DETECT, EMBOSS
    };

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);
        Bitmap inBitmap = BitmapFactory.decodeResource(getResources(), R.drawable.ic_launcher);
        Bitmap outBitmap = inBitmap.copy(inBitmap.getConfig(), true);
        setImageInView(outBitmap.copy(outBitmap.getConfig(), false), R.id.image_normal);
        final RenderScript rs = RenderScript.create(this);
        final Allocation input = Allocation.createFromBitmap(rs, inBitmap,
                Allocation.MipmapControl.MIPMAP_NONE,
                Allocation.USAGE_SCRIPT);
        final Allocation output = Allocation.createTyped(rs, input.getType());

        final ScriptIntrinsicBlur script = ScriptIntrinsicBlur.create(rs, Element.U8_4(rs));
        script.setRadius(4f);
        script.setInput(input);
        script.forEach(output);
        output.copyTo(outBitmap);
        setImageInView(outBitmap.copy(outBitmap.getConfig(), false), R.id.image_blurred);

        final ScriptIntrinsicColorMatrix scriptColor = ScriptIntrinsicColorMatrix.create(rs, Element.U8_4(rs));
        scriptColor.setGreyscale();
        scriptColor.forEach(input, output);
        output.copyTo(outBitmap);
        setImageInView(outBitmap.copy(outBitmap.getConfig(), false), R.id.image_greyscale);

        ScriptIntrinsicConvolve3x3 scriptC = ScriptIntrinsicConvolve3x3.create(rs, Element.U8_4(rs));
        scriptC.setCoefficients(getCoefficients(ConvolutionFilter.SHARPEN));
        scriptC.setInput(input);
        scriptC.forEach(output);
        output.copyTo(outBitmap);
        setImageInView(outBitmap.copy(outBitmap.getConfig(), false), R.id.image_sharpen);

        scriptC = ScriptIntrinsicConvolve3x3.create(rs, Element.U8_4(rs));
        scriptC.setCoefficients(getCoefficients(ConvolutionFilter.EDGE_DETECT));
        scriptC.setInput(input);
        scriptC.forEach(output);
        output.copyTo(outBitmap);
        setImageInView(outBitmap.copy(outBitmap.getConfig(), false), R.id.image_edge);

        scriptC = ScriptIntrinsicConvolve3x3.create(rs, Element.U8_4(rs));
        scriptC.setCoefficients(getCoefficients(ConvolutionFilter.EMBOSS));
        scriptC.setInput(input);
        scriptC.forEach(output);
        output.copyTo(outBitmap);
        setImageInView(outBitmap.copy(outBitmap.getConfig(), false), R.id.image_emboss);

        rs.destroy();
    }

    private void setImageInView(Bitmap bm, int viewId) {
        ImageView normalImage = (ImageView) findViewById(viewId);
        normalImage.setImageBitmap(bm);
    }
    private float[] getCoefficients(ConvolutionFilter filter) {
        switch (filter) {
            case SHARPEN:
                return new float[] {
                        0f, -1f, 0f,
                        -1f, 5f, -1f,
                        0f, -1f, 0f
                };
            case LIGHTEN:
                return new float[] {
                        0f, 0f, 0f,
                        0f, 1.5f, 0f,
                        0f, 0f, 0f
                };
            case DARKEN:
                return new float[] {
                        0f, 0f, 0f,
                        0f, 0.5f, 0f,
                        0f, 0f, 0f
                };
            case EDGE_DETECT:
                return new float[] {
                        0f, 1f, 0f,
                        1f, -3f, 1f,
                        0f, 1f, 0f
                };
            case EMBOSS:
                return new float[] {
                        -2f, -1f, 0f,
                        -1f, 1f, 1f,
                        0f, 1f, 2f
                };
            default:
                return null;
        }
    }
}

• Back to ImageView  ↑