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/* * Copyright (C) 2010 ZXing authors/*from w w w . j a va 2s . com*/ * * Licensed under the Apache License, Version 2.0 (the "License"); * you may not use this file except in compliance with the License. * You may obtain a copy of the License at * * http://www.apache.org/licenses/LICENSE-2.0 * * Unless required by applicable law or agreed to in writing, software * distributed under the License is distributed on an "AS IS" BASIS, * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. * See the License for the specific language governing permissions and * limitations under the License. */ package com.google.zxing.client.android.camera; import android.content.Context; import android.content.SharedPreferences; import android.graphics.Point; import android.hardware.Camera; import android.preference.PreferenceManager; import android.util.Log; import android.view.Display; import android.view.WindowManager; import eu.livotov.zxscan.AutofocusMode; import eu.livotov.zxscan.ZXScanHelper; import java.util.*; /** * A class which deals with reading, parsing, and setting the camera parameters which are used to * configure the camera hardware. */ final class CameraConfigurationManager { private static final String TAG = "CameraConfiguration"; // This is bigger than the size of a small screen, which is still supported. The routine // below will still select the default (presumably 320x240) size for these. This prevents // accidental selection of very low resolution on some devices. private static final int MIN_PREVIEW_PIXELS = 470 * 320; // normal screen private static final int MAX_PREVIEW_PIXELS = 1280 * 800; private final Context context; private Point screenResolution; private Point cameraResolution; CameraConfigurationManager(Context context) { this.context = context; } /** * Reads, one time, values from the camera that are needed by the app. */ void initFromCameraParameters(Camera camera) { Camera.Parameters parameters = camera.getParameters(); WindowManager manager = (WindowManager) context.getSystemService(Context.WINDOW_SERVICE); Display display = manager.getDefaultDisplay(); int width = display.getWidth(); int height = display.getHeight(); // We're landscape-only, and have apparently seen issues with display thinking it's portrait // when waking from sleep. If it's not landscape, assume it's mistaken and reverse them: if (width < height) { Log.i(TAG, "Display reports portrait orientation; assuming this is incorrect"); int temp = width; width = height; height = temp; } screenResolution = new Point(width, height); Log.i(TAG, "Screen resolution: " + screenResolution); cameraResolution = findBestPreviewSizeValue(parameters, screenResolution); Log.i(TAG, "Camera resolution: " + cameraResolution); } void setDesiredCameraParameters(Camera camera) { Camera.Parameters parameters = camera.getParameters(); if (parameters == null) { Log.w(TAG, "Device error: no camera parameters are available. Proceeding without configuration."); return; } SharedPreferences prefs = PreferenceManager.getDefaultSharedPreferences(context); initializeTorch(parameters, prefs, ZXScanHelper.isSafeMode()); String focusMode = null; //todo: control those settings boolean autofocus = ZXScanHelper.getAutofocusMode() != AutofocusMode.Off; boolean disableContinuousFocus = ZXScanHelper.getAutofocusMode() != AutofocusMode.Auto; if (autofocus) { if (disableContinuousFocus) { focusMode = findSettableValue(parameters.getSupportedFocusModes(), Camera.Parameters.FOCUS_MODE_AUTO); } else { focusMode = findSettableValue(parameters.getSupportedFocusModes(), "continuous-picture", // Camera.Parameters.FOCUS_MODE_CONTINUOUS_PICTURE in 4.0+ "continuous-video", // Camera.Parameters.FOCUS_MODE_CONTINUOUS_VIDEO in 4.0+ Camera.Parameters.FOCUS_MODE_AUTO); } } // Maybe selected auto-focus but not available, so fall through here: if (focusMode == null) { focusMode = findSettableValue(parameters.getSupportedFocusModes(), Camera.Parameters.FOCUS_MODE_MACRO, "edof"); // Camera.Parameters.FOCUS_MODE_EDOF in 2.2+ } if (focusMode != null) { parameters.setFocusMode(focusMode); } parameters.setPreviewSize(cameraResolution.x, cameraResolution.y); camera.setParameters(parameters); } Point getCameraResolution() { return cameraResolution; } Point getScreenResolution() { return screenResolution; } boolean getTorchState(Camera camera) { if (camera != null) { Camera.Parameters parameters = camera.getParameters(); if (parameters != null) { String flashMode = camera.getParameters().getFlashMode(); return flashMode != null && (Camera.Parameters.FLASH_MODE_ON.equals(flashMode) || Camera.Parameters.FLASH_MODE_TORCH.equals(flashMode)); } } return false; } void setTorch(Camera camera, boolean newSetting) { Camera.Parameters parameters = camera.getParameters(); doSetTorch(parameters, newSetting, false); camera.setParameters(parameters); } private void initializeTorch(Camera.Parameters parameters, SharedPreferences prefs, boolean safeMode) { doSetTorch(parameters, ZXScanHelper.getFrontLightMode() == FrontLightMode.ON, safeMode); } private void doSetTorch(Camera.Parameters parameters, boolean newSetting, boolean safeMode) { String flashMode; if (newSetting) { flashMode = findSettableValue(parameters.getSupportedFlashModes(), Camera.Parameters.FLASH_MODE_TORCH, Camera.Parameters.FLASH_MODE_ON); } else { flashMode = findSettableValue(parameters.getSupportedFlashModes(), Camera.Parameters.FLASH_MODE_OFF); } if (flashMode != null) { parameters.setFlashMode(flashMode); } /* SharedPreferences prefs = PreferenceManager.getDefaultSharedPreferences(context); if (!prefs.getBoolean(PreferencesActivity.KEY_DISABLE_EXPOSURE, false)) { if (!safeMode) { ExposureInterface exposure = new ExposureManager().build(); exposure.setExposure(parameters, newSetting); } } */ } private Point findBestPreviewSizeValue(Camera.Parameters parameters, Point screenResolution) { List<Camera.Size> rawSupportedSizes = parameters.getSupportedPreviewSizes(); if (rawSupportedSizes == null) { Log.w(TAG, "Device returned no supported preview sizes; using default"); Camera.Size defaultSize = parameters.getPreviewSize(); return new Point(defaultSize.width, defaultSize.height); } // Sort by size, descending List<Camera.Size> supportedPreviewSizes = new ArrayList<Camera.Size>(rawSupportedSizes); Collections.sort(supportedPreviewSizes, new Comparator<Camera.Size>() { @Override public int compare(Camera.Size a, Camera.Size b) { int aPixels = a.height * a.width; int bPixels = b.height * b.width; if (bPixels < aPixels) { return -1; } if (bPixels > aPixels) { return 1; } return 0; } }); if (Log.isLoggable(TAG, Log.INFO)) { StringBuilder previewSizesString = new StringBuilder(); for (Camera.Size supportedPreviewSize : supportedPreviewSizes) { previewSizesString.append(supportedPreviewSize.width).append('x') .append(supportedPreviewSize.height).append(' '); } Log.i(TAG, "Supported preview sizes: " + previewSizesString); } Point bestSize = null; float screenAspectRatio = (float) screenResolution.x / (float) screenResolution.y; float diff = Float.POSITIVE_INFINITY; for (Camera.Size supportedPreviewSize : supportedPreviewSizes) { int realWidth = supportedPreviewSize.width; int realHeight = supportedPreviewSize.height; int pixels = realWidth * realHeight; if (pixels < MIN_PREVIEW_PIXELS || pixels > MAX_PREVIEW_PIXELS) { continue; } boolean isCandidatePortrait = realWidth < realHeight; int maybeFlippedWidth = isCandidatePortrait ? realHeight : realWidth; int maybeFlippedHeight = isCandidatePortrait ? realWidth : realHeight; if (maybeFlippedWidth == screenResolution.x && maybeFlippedHeight == screenResolution.y) { Point exactPoint = new Point(realWidth, realHeight); Log.i(TAG, "Found preview size exactly matching screen size: " + exactPoint); return exactPoint; } float aspectRatio = (float) maybeFlippedWidth / (float) maybeFlippedHeight; float newDiff = Math.abs(aspectRatio - screenAspectRatio); if (newDiff < diff) { bestSize = new Point(realWidth, realHeight); diff = newDiff; } } if (bestSize == null) { Camera.Size defaultSize = parameters.getPreviewSize(); bestSize = new Point(defaultSize.width, defaultSize.height); Log.i(TAG, "No suitable preview sizes, using default: " + bestSize); } Log.i(TAG, "Found best approximate preview size: " + bestSize); return bestSize; } private static String findSettableValue(Collection<String> supportedValues, String... desiredValues) { Log.i(TAG, "Supported values: " + supportedValues); String result = null; if (supportedValues != null) { for (String desiredValue : desiredValues) { if (supportedValues.contains(desiredValue)) { result = desiredValue; break; } } } Log.i(TAG, "Settable value: " + result); return result; } }