Java tutorial
/** * An Image Resizer Plugin for Cordova/PhoneGap. * * More Information : https://github.com/raananw/ * * The android version of the file stores the images using the local storage. * * The software is open source, MIT Licensed. * Copyright (C) 2012, webXells GmbH All Rights Reserved. * * @author Raanan Weber, webXells GmbH, http://www.webxells.com */ package com.synconset; import java.io.ByteArrayOutputStream; import java.io.File; import java.io.FileInputStream; import java.io.FileOutputStream; import java.io.IOException; import java.io.OutputStream; import java.net.URI; import java.net.URISyntaxException; import org.apache.cordova.CallbackContext; import org.apache.cordova.CordovaPlugin; import org.json.JSONArray; import org.json.JSONException; import org.json.JSONObject; import android.graphics.Bitmap; import android.graphics.BitmapFactory; import android.graphics.Matrix; import android.os.Environment; import android.util.Base64; import android.util.Log; import android.util.DisplayMetrics; public class ImageResizePlugin extends CordovaPlugin { public static final String IMAGE_DATA_TYPE_BASE64 = "base64Image"; public static final String IMAGE_DATA_TYPE_URL = "urlImage"; public static final String RESIZE_TYPE_FACTOR = "factorResize"; public static final String RESIZE_TYPE_MIN_PIXEL = "minPixelResize"; public static final String RESIZE_TYPE_MAX_PIXEL = "maxPixelResize"; public static final String RETURN_BASE64 = "returnBase64"; public static final String RETURN_URI = "returnUri"; public static final String FORMAT_JPG = "jpg"; public static final String FORMAT_PNG = "png"; public static final String DEFAULT_FORMAT = "jpg"; public static final String DEFAULT_IMAGE_DATA_TYPE = IMAGE_DATA_TYPE_BASE64; public static final String DEFAULT_RESIZE_TYPE = RESIZE_TYPE_FACTOR; @Override public boolean execute(String action, JSONArray data, CallbackContext callbackContext) throws JSONException { JSONObject params = data.getJSONObject(0); if (action.equals("resizeImage")) { ResizeImage resizeImage = new ResizeImage(params, callbackContext); cordova.getThreadPool().execute(resizeImage); return true; } else if (action.equals("imageSize")) { GetImageSize imageSize = new GetImageSize(params, callbackContext); cordova.getThreadPool().execute(imageSize); return true; } else { Log.d("PLUGIN", "unknown action"); return false; } } private class ImageTools { protected JSONObject params; protected CallbackContext callbackContext; protected String format; protected String imageData; protected String imageDataType; public ImageTools(JSONObject params, CallbackContext callbackContext) throws JSONException { this.params = params; this.callbackContext = callbackContext; imageData = params.getString("data"); imageDataType = DEFAULT_IMAGE_DATA_TYPE; if (params.has("imageDataType")) { imageDataType = params.getString("imageDataType"); } format = DEFAULT_FORMAT; if (params.has("format")) { format = params.getString("format"); } } protected Bitmap getBitmap(String imageData, String imageDataType, BitmapFactory.Options options) throws IOException, URISyntaxException { Bitmap bmp; if (imageDataType.equals(IMAGE_DATA_TYPE_BASE64)) { byte[] blob = Base64.decode(imageData, Base64.DEFAULT); bmp = BitmapFactory.decodeByteArray(blob, 0, blob.length, options); } else { URI uri = new URI(imageData); File imageFile = new File(uri); bmp = BitmapFactory.decodeFile(imageFile.getAbsolutePath(), options); } return bmp; } } private class GetImageSize extends ImageTools implements Runnable { public GetImageSize(JSONObject params, CallbackContext callbackContext) throws JSONException { super(params, callbackContext); } @Override public void run() { try { BitmapFactory.Options options = new BitmapFactory.Options(); options.inJustDecodeBounds = true; Bitmap bmp = getBitmap(imageData, imageDataType, options); JSONObject res = new JSONObject(); res.put("width", options.outWidth); res.put("height", options.outHeight); callbackContext.success(res); } catch (JSONException e) { callbackContext.error(e.getMessage()); } catch (IOException e) { Log.d("PLUGIN", e.getMessage()); callbackContext.error(e.getMessage()); } catch (URISyntaxException e) { Log.d("PLUGIN", e.getMessage()); callbackContext.error(e.getMessage()); } } } private class ResizeImage extends ImageTools implements Runnable { public ResizeImage(JSONObject params, CallbackContext callbackContext) throws JSONException { super(params, callbackContext); } @Override public void run() { try { BitmapFactory.Options options = new BitmapFactory.Options(); options.inJustDecodeBounds = true; getBitmap(imageData, imageDataType, options); float[] sizes = calculateFactors(params, options.outWidth, options.outHeight); float reqWidth = options.outWidth * sizes[0]; float reqHeight = options.outHeight * sizes[1]; int inSampleSize = calculateInSampleSize(options, (int) reqWidth, (int) reqHeight); options = new BitmapFactory.Options(); options.inSampleSize = inSampleSize; Bitmap bmp = getBitmap(imageData, imageDataType, options); if (bmp == null) { throw new IOException("The image file could not be opened."); } sizes = calculateFactors(params, options.outWidth, options.outHeight); bmp = getResizedBitmap(bmp, sizes[0], sizes[1]); int quality = params.getInt("quality"); ByteArrayOutputStream baos = new ByteArrayOutputStream(); if (format.equals(FORMAT_PNG)) { bmp.compress(Bitmap.CompressFormat.PNG, quality, baos); } else { bmp.compress(Bitmap.CompressFormat.JPEG, quality, baos); } byte[] b = baos.toByteArray(); String returnString = Base64.encodeToString(b, Base64.DEFAULT); // return object JSONObject res = new JSONObject(); res.put("imageData", returnString); res.put("width", bmp.getWidth()); res.put("height", bmp.getHeight()); callbackContext.success(res); } catch (JSONException e) { Log.d("PLUGIN", e.getMessage()); callbackContext.error(e.getMessage()); } catch (IOException e) { Log.d("PLUGIN", e.getMessage()); callbackContext.error(e.getMessage()); } catch (URISyntaxException e) { Log.d("PLUGIN", e.getMessage()); callbackContext.error(e.getMessage()); } } private Bitmap getResizedBitmap(Bitmap bm, float widthFactor, float heightFactor) { int width = bm.getWidth(); int height = bm.getHeight(); // create a matrix for the manipulation Matrix matrix = new Matrix(); // resize the bit map matrix.postScale(widthFactor, heightFactor); // recreate the new Bitmap Bitmap resizedBitmap = Bitmap.createBitmap(bm, 0, 0, width, height, matrix, false); return resizedBitmap; } private int calculateInSampleSize(BitmapFactory.Options options, int reqWidth, int reqHeight) { // Raw height and width of image final int height = options.outHeight; final int width = options.outWidth; int inSampleSize = 1; if (height > reqHeight || width > reqWidth) { final int halfHeight = height / 2; final int halfWidth = width / 2; // Calculate the largest inSampleSize value that is a power of 2 and keeps both // height and width larger than the requested height and width. while ((halfHeight / inSampleSize) > reqHeight && (halfWidth / inSampleSize) > reqWidth) { inSampleSize *= 2; } } return inSampleSize; } private float[] calculateFactors(JSONObject params, int width, int height) throws JSONException { float widthFactor; float heightFactor; String resizeType = params.getString("resizeType"); float desiredWidth = (float) params.getDouble("width"); float desiredHeight = (float) params.getDouble("height"); if (resizeType.equals(RESIZE_TYPE_MIN_PIXEL)) { widthFactor = desiredWidth / (float) width; heightFactor = desiredHeight / (float) height; if (widthFactor > heightFactor && widthFactor <= 1.0) { heightFactor = widthFactor; } else if (heightFactor <= 1.0) { widthFactor = heightFactor; } else { widthFactor = 1.0f; heightFactor = 1.0f; } } else if (resizeType.equals(RESIZE_TYPE_MAX_PIXEL)) { widthFactor = desiredWidth / (float) width; heightFactor = desiredHeight / (float) height; if (widthFactor == 0.0) { widthFactor = heightFactor; } else if (heightFactor == 0.0) { heightFactor = widthFactor; } else if (widthFactor > heightFactor) { widthFactor = heightFactor; // scale to fit height } else { heightFactor = widthFactor; // scale to fit width } } else { widthFactor = desiredWidth; heightFactor = desiredHeight; } if (params.getBoolean("pixelDensity")) { DisplayMetrics metrics = cordova.getActivity().getResources().getDisplayMetrics(); if (metrics.density > 1) { if (widthFactor * metrics.density < 1.0 && heightFactor * metrics.density < 1.0) { widthFactor *= metrics.density; heightFactor *= metrics.density; } else { widthFactor = 1.0f; heightFactor = 1.0f; } } } float[] sizes = { widthFactor, heightFactor }; return sizes; } } }