"Android Advanced" (3) Android image processing

1. Concept

Hue/hue: The color of an object's passing

Saturation: The purity of the color, from 0 (gray) to 100% (saturated) to describe the description

Brightness/lightness: The relative degree of light and shade of color

2. Adjust Image Small Demo

Create a tool class. Three parameters used to set the image:

/** * * @param BM * image * @param hue * hue * @param saturation * saturation * @param lum *  Brightness * @return */public static Bitmap Handleimageeffect (Bitmap BM, float hue, float saturation,float Lum) {Bitmap bmp = Bitmap.createbitmap (Bm.getwidth (), Bm.getheight (), Bitmap.Config.ARGB_8888); Canvas canvas = new canvas (BMP);//Set anti-aliasing paint paint = new paint (paint.anti_alias_flag);//adjust hue colormatrix Huematrix = new ColorMatrix (); huematrix.setrotate (0, Hue), huematrix.setrotate (1, hue); Huematrix.setrotate (2, hue);// Saturation ColorMatrix Satmatrix = new ColorMatrix () satmatrix.setsaturation (saturation);//Set brightness colormatrix LumMatrix = new ColorMatrix (); Lummatrix.setscale (Lum, Lum, Lum, 1);//Three settings fused ColorMatrix Imagematrix = new ColorMatrix (); Imagematrix.postconcat (Huematrix); Imagematrix.postconcat (Satmatrix); Imagematrix.postconcat (LumMatrix); Paint.setcolorfilter (New Colormatrixcolorfilter (Imagematrix)); Canvas.drawbitmap (BM, 0, 0, paint); return bmp;}

Then we create a imageview and three Seekbar in the layout file to adjust the parameters and implement the Onseekbarchangelistener interface in the activity:

Private ImageView mimageview;private SeekBar mseekbarhue;private SeekBar mseekbarsat;private SeekBar mseekbarlum; private static int max_value = 255; Seekbar scale maximum value private static int mid_value = 127; Seekbar Middle value private float Mhue; Hue private float mSat; Saturation of private float mlum; Brightness private Bitmap mbitmap; @Overrideprotected void OnCreate (Bundle savedinstancestate) {super.oncreate ( Savedinstancestate); Setcontentview (R.layout.activity_primarycolor); Initview ();} private void Initview () {Mimageview = (ImageView) Findviewbyid (r.id.imageview); Mseekbarhue = (SeekBar) Findviewbyid ( R.id.seekbar_hue); Mseekbarsat = (Seekbar) Findviewbyid (R.ID.SEEKBAR_SAT); mseekbarlum = (Seekbar) Findviewbyid ( R.id.seekbar_lum);//Set the Seekbar maximum value of the scale Mseekbarhue.setmax (max_value); Mseekbarsat.setmax (Max_value); Mseekbarlum.setmax (max_value);//Set Seekbar initial value in the middle mseekbarhue.setprogress (Mid_value); Mseekbarsat.setprogress (MID_ VALUE); mseekbarlum.setprogress (Mid_value); Mseekbarhue.setonseekbarchangelistener (this); Mseekbarsat.Setonseekbarchangelistener (This), Mseekbarlum.setonseekbarchangelistener (this); Mbitmap = Bitmapfactory.decoderesource (Getresources (), r.drawable.test3); Mimageview.setimagebitmap (MBitmap);} @Overridepublic void onprogresschanged (SeekBar SeekBar, int progress,boolean fromuser) {switch (Seekbar.getid ()) {case R . Id.seekbar_hue:mHue = (progress-mid_value) * 1.0f/mid_value * 180;break;case R.id.seekbar_sat:msat = progress * 1.0F /Mid_value;break;case R.id.seekbar_lum:mlum = progress * 1.0f/mid_value;break;} Bitmap bmp = Imagehelper.handleimageeffect (Mbitmap, Mhue, MSat, Mlum); Mimageview.setimagebitmap (BMP);} @Overridepublic void Onstarttrackingtouch (SeekBar SeekBar) {} @Overridepublic void Onstoptrackingtouch (SeekBar SeekBar ) {}

3. Color Matrix Transformation

Principle:

Create a new layout:

<linearlayout xmlns:android= "http://schemas.android.com/apk/res/android" xmlns:tools= "http// Schemas.android.com/tools "android:layout_width=" match_parent "android:layout_height=" Match_parent "Android:orien tation= "vertical" > <imageview android:id= "@+id/imageview" android:layout_width= "300DP" Android oid:layout_height= "0DP" android:layout_gravity= "Center_horizontal" android:layout_margin= "20DP" Andro        id:layout_weight= "2"/> <gridlayout android:id= "@+id/group" android:layout_width= "Match_parent" android:layout_height= "0DP" android:layout_weight= "3" android:columncount= "5" android:rowcount= "4 "/> <button android:layout_width=" match_parent "android:layout_height=" Wrap_content "Androi d:onclick= "Btnchange" android:text= "Change"/> <button android:layout_width= "Match_parent" a Ndroid:layout_height= "Wrap_content" Androidoid:onclick= "Btnreset" android:text= "Reset"/></linearlayout> 

Write acitvity:

public class Colormatrixactivity extends Activity {private ImageView mimageview;private GridLayout mgroup;private Bitmap mbitmap;private int medittextwidth, medittextheight;private edittext[] mEts = new EDITTEXT[20];p rivate float[] Mcolormatrix = new float[20]; @Overrideprotected void OnCreate (Bundle savedinstancestate) {super.oncreate ( Savedinstancestate); Setcontentview (R.layout.activity_colormatrix); Initview ();} private void Initview () {mbitmap = Bitmapfactory.decoderesource (Getresources (), r.drawable.test1); Mimageview = ( ImageView) Findviewbyid (r.id.imageview); mgroup = (GridLayout) Findviewbyid (R.id.group); Mimageview.setimagebitmap ( MBITMAP) Mgroup.post (new Runnable () {@Overridepublic void Run () {//Initialize each edittext width and height medittextwidth = mgroup.getwidth ( )/5;medittextheight = Mgroup.getheight ()/4;addedittext (); Initmatrix ();}}); /** * Create each EditText and add to the array to save */private void Addedittext () {for (int i = 0; i <; i++) {EditText EditText = new Editte XT (this); Mets[i] = Edittext;mgroup.addvieW (EditText, Medittextwidth, medittextheight);}} /** * initialization matrix */private void Initmatrix () {for (int i = 0; i <; i++) {if (i% 6 = = 0) {Mets[i].settext (string.valueof ( 1));} else {mets[i].settext (string.valueof (0));}}} /** * Gets the value of each edittext, assigns the array */private void Getmatrix () {for (int i = 0; i <; i++) {Mcolormatrix[i] = float.valueof (mEt S[i].gettext (). toString ());}} /** * Set the new color matrix to the canvas */private void Setimagematrix () {Bitmap Bitmap = Bitmap.createbitmap (Mbitmap.getwidth (), Mbitmap.getheight (), Bitmap.Config.ARGB_8888); ColorMatrix ColorMatrix = new ColorMatrix (); Colormatrix.set (Mcolormatrix); Canvas canvas = new canvas (bitmap); Paint paint = new Paint (paint.anti_alias_flag);p aint.setcolorfilter (New Colormatrixcolorfilter (ColorMatrix)); Canvas.drawbitmap (mbitmap, 0, 0, paint); Mimageview.setimagebitmap (bitmap);} /** * Run Change color matrix * * @param v */public void Btnchange (View v) {Getmatrix (); Setimagematrix ();} public void Btnreset (View v) {Initmatrix (); Getmatrix (); Setimagematrix ();}}

4. Pixel Point Analysis

Negative effect algorithm:

NEWR = 255-oldr;

NEWG = 255-OLDG;

newb = 255-oldb;

Old photo effect:

NEWR = (int) (0.393 * oldr + 0.769 * oldg + 0.189 * oldb);

NEWG = (int) (0.349 * oldr + 0.686 * oldg + 0.168 * oldb);

Newb = (int) (0.272 * oldr + 0534 * oldg + 0.131* oldb);

Emboss Effect:

There are ABC three points. To find the B-spot emboss effect:

B.R = C.R-B.R + 127;

B.G = c.g-b.g + 127;

B.B = c.b-b.b + 127;

Expand the Imagehelper tool class and write a method for converting to a negative effect:

/** * Processing the picture into a negative effect *  * @param BM * @return */public static Bitmap handlerimagenegative (Bitmap BM) {int width = Bm.getwid th (); int height = bm.getheight ();//Use an array of width times high to hold all pixels int[] Oldpx = new int[width * height];int[] newpx = new Int[width * Height];int Color;int R, G, B, A; Save the extracted component in color Bitmap BMP = Bitmap.createbitmap (width, height, Bitmap.Config.ARGB_8888); Bm.getpixels (oldpx, 0, width, 0, 0 , width, height), for (int i = 0; I < width * height; i++) {color = oldpx[i];//out each component R = color.red (color); g = Color.gre  En (color), B = color.blue (color), a = Color.alpha (color), r = 255-r;g = 255-g;b = 255-b;if (R > 255) {r = 255;} else if (r < 0) {R = 0;} if (g > 255) {g = 255;} else if (G < 0) {g = 0;} if (b > 255) {b = 255;} else if (b < 0) {b = 0;} Newpx[i] = Color.argb (A, R, G, b);} Bmp.setpixels (newpx, 0, width, 0, 0, width, height); return bmp;}

Write the corresponding code in the activity:

Mimageview2.setimagebitmap (imagehelper.handlerimagenegative (bitmap));

Photo-nostalgic effect processing:

/** * Image processing as a nostalgic effect *  * @param BM * @return */public static Bitmap Handlerimageoldphoto (Bitmap BM) {int width = Bm.getwid th (); int height = bm.getheight ();//Use an array of width times high to hold all pixels int[] Oldpx = new int[width * height];int[] newpx = new Int[width * Height];int Color;int R, G, B, A; Save the extracted component in color Bitmap BMP = Bitmap.createbitmap (width, height, Bitmap.Config.ARGB_8888); Bm.getpixels (oldpx, 0, width, 0, 0 , width, height), for (int i = 0; I < width * height; i++) {color = oldpx[i];//out each component R = color.red (color); g = Color.gre En (color), B = color.blue (color), a = Color.alpha (color), r = (int) (0.393 * r + 0.769 * g + 0.189 * b); g = (int) (0.349 * r + 0.686 * g + 0.168 * b); b = (int) (0.272 * r + 0534 * g + 0.131 * b); if (R > 255) {r = 255;} if (g > 255) {g = 255;} if (b > 255) {b = 255;} Newpx[i] = Color.argb (A, R, G, b);} Bmp.setpixels (newpx, 0, width, 0, 0, width, height); return bmp;}

handling of photo relief effects:

/** * Image processing as embossed effect * * @param BM * @return */public static Bitmap Handlerimagerilievo (Bitmap BM) {int width = bm.getwidth () ; int height = bm.getheight ();//Use an array of width times high to hold all pixels int[] Oldpx = new int[width * height];int[] newpx = new Int[width * Heig Ht];int Color;int R, G, B, A; Save the color out of the component int R1, G1, B1; Save the component int colorbefore in the color; The pixel value before saving Bitmap bmp = Bitmap.createbitmap (width, height, Bitmap.Config.ARGB_8888); Bm.getpixels (oldpx, 0, width, 0, 0, W Idth, height); for (int i = 1; i < width * height; i++) {Colorbefore = Oldpx[i-1];r = Color.Red (colorbefore); g = Color . Green (colorbefore); b = Color.Blue (Colorbefore); a = Color.alpha (Colorbefore); Color = oldpx[i];//Remove each component R1 = color.red ( color); g1 = Color.green (color); b1 = Color.Blue (color); r = r-r1 + 127;g = g-g1 + 127;b = b-b1 + 127;if (R > 255) { R = 255;} if (g > 255) {g = 255;} if (b > 255) {b = 255;} Newpx[i] = Color.argb (A, R, G, b);} Bmp.setpixels (newpx, 0, width, 0, 0, width, height); return bmp;}

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"Android Advanced" (3) Android image processing