Java Config.RGB_565屬性代碼示例

/**
 * Return the byte usage per pixel of a bitmap based on its configuration.
 * @param config The bitmap configuration.
 * @return The byte usage per pixel.
 */
private static int getBytesPerPixel(Config config) {
    if (config == Config.ARGB_8888) {
        return 4;
    } else if (config == Config.RGB_565) {
        return 2;
    } else if (config == Config.ARGB_4444) {
        return 2;
    } else if (config == Config.ALPHA_8) {
        return 1;
    }
    return 1;
}
 

protected Request<Bitmap> makeImageRequest(String requestUrl, int maxWidth, int maxHeight,
        ScaleType scaleType, final String cacheKey) {
    return new ImageRequest(requestUrl, new Listener<Bitmap>() {
        @Override
        public void onResponse(Bitmap response) {
            onGetImageSuccess(cacheKey, response);
        }
    }, maxWidth, maxHeight, scaleType, Config.RGB_565, new ErrorListener() {
        @Override
        public void onErrorResponse(VolleyError error) {
            onGetImageError(cacheKey, error);
        }
    });
}
 

/**
 * 獲取一個指定大小的bitmap
 *
 * @param res       Resources
 * @param resId     圖片ID
 * @param reqWidth  目標寬度
 * @param reqHeight 目標高度
 */
public static Bitmap getBitmapFromResource(Resources res, int resId,
                                           int reqWidth, int reqHeight) {
    // BitmapFactory.Options options = new BitmapFactory.Options();
    // options.inJustDecodeBounds = true;
    // BitmapFactory.decodeResource(res, resId, options);
    // options = BitmapHelper.calculateInSampleSize(options, reqWidth,
    // reqHeight);
    // return BitmapFactory.decodeResource(res, resId, options);

    // 通過JNI的形式讀取本地圖片達到節省內存的目的
    BitmapFactory.Options options = new BitmapFactory.Options();
    options.inPreferredConfig = Config.RGB_565;
    options.inPurgeable = true;
    options.inInputShareable = true;
    InputStream is = res.openRawResource(resId);
    return getBitmapFromStream(is, null, reqWidth, reqHeight);
}
 

private static final boolean b(String str, int i, int i2) {
    if (TextUtils.isEmpty(str)) {
        return false;
    }
    Options options = new Options();
    options.inJustDecodeBounds = true;
    BitmapFactory.decodeFile(str, options);
    int i3 = options.outWidth;
    int i4 = options.outHeight;
    if (options.mCancel || options.outWidth == -1 || options.outHeight == -1) {
        return false;
    }
    int i5 = i3 > i4 ? i3 : i4;
    if (i3 >= i4) {
        i3 = i4;
    }
    f.b("AsynScaleCompressImage", "longSide=" + i5 + "shortSide=" + i3);
    options.inPreferredConfig = Config.RGB_565;
    if (i5 > i2 || i3 > i) {
        return true;
    }
    return false;
}
 

private void verifyResize(NetworkResponse networkResponse, int maxWidth, int maxHeight,
                          ScaleType scaleType, int expectedWidth, int expectedHeight) {
    ImageRequest request = new ImageRequest("", null, maxWidth, maxHeight, scaleType,
            Config.RGB_565, null);
    Response<Bitmap> response = request.parseNetworkResponse(networkResponse);
    assertNotNull(response);
    assertTrue(response.isSuccess());
    Bitmap bitmap = response.result;
    assertNotNull(bitmap);
    assertEquals(expectedWidth, bitmap.getWidth());
    assertEquals(expectedHeight, bitmap.getHeight());
}
 

protected Request<Bitmap> makeImageRequest(String requestUrl, int maxWidth, int maxHeight, ScaleType scaleType, final String cacheKey) {
    return new ImageRequest(requestUrl, new Listener<Bitmap>() {
        public void onResponse(Bitmap response) {
            ImageLoader.this.onGetImageSuccess(cacheKey, response);
        }
    }, maxWidth, maxHeight, scaleType, Config.RGB_565, new ErrorListener() {
        public void onErrorResponse(VolleyError error) {
            ImageLoader.this.onGetImageError(cacheKey, error);
        }
    });
}
 

/**
 * Return the byte usage per pixel of a bitmap based on its configuration.
 * 
 * @param config
 *            The bitmap configuration.
 * @return The byte usage per pixel.
 */
private static int getBytesPerPixel(Config config) {
	if (config == Config.ARGB_8888) {
		return 4;
	} else if (config == Config.RGB_565) {
		return 2;
	} else if (config == Config.ARGB_4444) {
		return 2;
	} else if (config == Config.ALPHA_8) {
		return 1;
	}
	return 1;
}
 

/**
 * 以最省內存的方式讀取本地資源的圖片
 * 
 * @param context
 * @param resId
 * @return
 */
public static Bitmap readBitMap(Context context, int resId) {
	Options opt = new Options();
	opt.inPreferredConfig = Config.RGB_565;
	opt.inPurgeable = true;
	opt.inInputShareable = true;
	// 獲取資源圖片
	InputStream is = context.getResources().openRawResource(resId);
	return BitmapFactory.decodeStream(is, null, opt);
}
 

private void verifyResize(NetworkResponse networkResponse, int maxWidth, int maxHeight,
        int expectedWidth, int expectedHeight) {
    ImageRequest request = new ImageRequest(
            "", null, maxWidth, maxHeight, Config.RGB_565, null);
    Response<Bitmap> response = request.parseNetworkResponse(networkResponse);
    assertNotNull(response);
    assertTrue(response.isSuccess());
    Bitmap bitmap = response.result;
    assertNotNull(bitmap);
    assertEquals(expectedWidth, bitmap.getWidth());
    assertEquals(expectedHeight, bitmap.getHeight());
}
 

/**
     * Compress image by pixel, this will modify image width/height.
     * Used to get thumbnail
     *
     * @param imgPath image path
     * @param pixelW  target pixel of width
     * @param pixelH  target pixel of height
     * @return
     */
    public Bitmap ratio(String imgPath, float pixelW, float pixelH) {
        BitmapFactory.Options newOpts = new BitmapFactory.Options();
        // 開始讀入圖片，此時把options.inJustDecodeBounds 設回true，即隻讀邊不讀內容
        newOpts.inJustDecodeBounds = true;
        newOpts.inPreferredConfig = Config.RGB_565;
        // Get bitmap info, but notice that bitmap is null now
        Bitmap bitmap = BitmapFactory.decodeFile(imgPath, newOpts);

        newOpts.inJustDecodeBounds = false;
        int w = newOpts.outWidth;
        int h = newOpts.outHeight;
        // 想要縮放的目標尺寸
        float hh = pixelH;// 設置高度為240f時，可以明顯看到圖片縮小了
        float ww = pixelW;// 設置寬度為120f，可以明顯看到圖片縮小了
        // 縮放比。由於是固定比例縮放，隻用高或者寬其中一個數據進行計算即可
        int be = 1;//be=1表示不縮放
        if (w > h && w > ww) {//如果寬度大的話根據寬度固定大小縮放
            be = (int) (newOpts.outWidth / ww);
        } else if (w < h && h > hh) {//如果高度高的話根據寬度固定大小縮放
            be = (int) (newOpts.outHeight / hh);
        }
        if (be <= 0) be = 1;
        newOpts.inSampleSize = be;//設置縮放比例
        // 開始壓縮圖片，注意此時已經把options.inJustDecodeBounds 設回false了
        bitmap = BitmapFactory.decodeFile(imgPath, newOpts);
        // 壓縮好比例大小後再進行質量壓縮
//        return compress(bitmap, maxSize); // 這裏再進行質量壓縮的意義不大，反而耗資源，刪除
        return bitmap;
    }
 

public static Bitmap getBitmap(InputStream inputStream, int i) {
    if (inputStream == null) {
        return null;
    }
    Options options = new Options();
    options.inPreferredConfig = Config.RGB_565;
    options.inPurgeable = true;
    options.inInputShareable = true;
    options.inSampleSize = i;
    return BitmapFactory.decodeStream(inputStream, null, options);
}
 

@SuppressWarnings("deprecation")
private void calculateConfig(
    InputStream is,
    DecodeFormat format,
    boolean isHardwareConfigAllowed,
    boolean isExifOrientationRequired,
    BitmapFactory.Options optionsWithScaling,
    int targetWidth,
    int targetHeight) {

  if (hardwareConfigState.setHardwareConfigIfAllowed(
      targetWidth,
      targetHeight,
      optionsWithScaling,
      format,
      isHardwareConfigAllowed,
      isExifOrientationRequired)) {
    return;
  }

  // Changing configs can cause skewing on 4.1, see issue #128.
  if (format == DecodeFormat.PREFER_ARGB_8888
      || format == DecodeFormat.PREFER_ARGB_8888_DISALLOW_HARDWARE
      || Build.VERSION.SDK_INT == Build.VERSION_CODES.JELLY_BEAN) {
    optionsWithScaling.inPreferredConfig = Bitmap.Config.ARGB_8888;
    return;
  }

  boolean hasAlpha = false;
  try {
    hasAlpha = ImageHeaderParserUtils.getType(parsers, is, byteArrayPool).hasAlpha();
  } catch (IOException e) {
    if (Log.isLoggable(TAG, Log.DEBUG)) {
      Log.d(TAG, "Cannot determine whether the image has alpha or not from header"
          + ", format " + format, e);
    }
  }

  optionsWithScaling.inPreferredConfig =
      hasAlpha ? Bitmap.Config.ARGB_8888 : Bitmap.Config.RGB_565;
  if (optionsWithScaling.inPreferredConfig == Config.RGB_565) {
    optionsWithScaling.inDither = true;
  }
}
 

/**
 * Issues a bitmap request with the given URL if that image is not available
 * in the cache, and returns a bitmap container that contains all of the data
 * relating to the request (as well as the default image if the requested
 * image is not available).
 * @param requestUrl The url of the remote image
 * @param imageListener The listener to call when the remote image is loaded
 * @param maxWidth The maximum width of the returned image.
 * @param maxHeight The maximum height of the returned image.
 * @return A container object that contains all of the properties of the request, as well as
 *     the currently available image (default if remote is not loaded).
 */
public ImageContainer get(String requestUrl, ImageListener imageListener,
        int maxWidth, int maxHeight) {
    // only fulfill requests that were initiated from the main thread.
    throwIfNotOnMainThread();

    final String cacheKey = getCacheKey(requestUrl, maxWidth, maxHeight);

    // Try to look up the request in the cache of remote images.
    Bitmap cachedBitmap = mCache.getBitmap(cacheKey);
    if (cachedBitmap != null) {
        // Return the cached bitmap.
        ImageContainer container = new ImageContainer(cachedBitmap, requestUrl, null, null);
        imageListener.onResponse(container, true);
        return container;
    }

    // The bitmap did not exist in the cache, fetch it!
    ImageContainer imageContainer =
            new ImageContainer(null, requestUrl, cacheKey, imageListener);

    // Update the caller to let them know that they should use the default bitmap.
    imageListener.onResponse(imageContainer, true);

    // Check to see if a request is already in-flight.
    BatchedImageRequest request = mInFlightRequests.get(cacheKey);
    if (request != null) {
        // If it is, add this request to the list of listeners.
        request.addContainer(imageContainer);
        return imageContainer;
    }

    // The request is not already in flight. Send the new request to the network and
    // track it.
    Request<?> newRequest =
        new ImageRequest(requestUrl, new Listener<Bitmap>() {
            @Override
            public void onResponse(Bitmap response) {
                onGetImageSuccess(cacheKey, response);
            }
        }, maxWidth, maxHeight,
        Config.RGB_565, new ErrorListener() {
            @Override
            public void onErrorResponse(VolleyError error) {
                onGetImageError(cacheKey, error);
            }
        });

    mRequestQueue.add(newRequest);
    mInFlightRequests.put(cacheKey,
            new BatchedImageRequest(newRequest, imageContainer));
    return imageContainer;
}
 

protected Request a(String str, int i, int i2, ScaleType scaleType, String str2) {
    return new n(str, new h(this, str2), i, i2, scaleType, Config.RGB_565);
}