| /** |
| * Copyright (C) 2015 The Android Open Source Project |
| * |
| * 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.android.gallery3d.common; |
| |
| import android.content.Context; |
| import android.media.ExifInterface; |
| import android.util.Log; |
| |
| import java.io.DataInputStream; |
| import java.io.DataOutputStream; |
| import java.io.File; |
| import java.io.FileOutputStream; |
| import java.io.IOException; |
| import java.io.InputStream; |
| |
| public class ExifOrientation { |
| private static final String TAG = "ExifOrientation"; |
| private static final boolean DEBUG = false; |
| |
| private static final short SOI = (short) 0xFFD8; // start of input |
| private static final short APP0 = (short) 0xFFE0; |
| private static final short APPF = (short) 0xFFEF; |
| private static final short APP1 = (short) 0xFFE1; |
| private static final short SOS = (short) 0xFFDA; // start of stream |
| private static final short EOI = (short) 0xFFD9; // end of input |
| |
| // The header is available in first 64 bytes, so reading upto 128 bytes |
| // should be more than enough. |
| private static final int MAX_BYTES_TO_READ = 128 * 1024; |
| |
| /** |
| * Parses the rotation of the JPEG image from the input stream. |
| */ |
| public static final int readRotation(InputStream in, Context context) { |
| // Since the platform implementation only takes file input, create a temporary file |
| // with just the image header. |
| File tempFile = null; |
| DataOutputStream tempOut = null; |
| |
| try { |
| DataInputStream din = new DataInputStream(in); |
| int pos = 0; |
| if (din.readShort() == SOI) { |
| pos += 2; |
| |
| short marker = din.readShort(); |
| pos += 2; |
| |
| while ((marker >= APP0 && marker <= APPF) && pos < MAX_BYTES_TO_READ) { |
| int length = din.readUnsignedShort(); |
| if (length < 2) { |
| throw new IOException("Invalid header size"); |
| } |
| |
| // We only want APP1 headers |
| if (length > 2) { |
| if (marker == APP1) { |
| // Copy the header |
| if (tempFile == null) { |
| tempFile = File.createTempFile(TAG, ".jpg", context.getCacheDir()); |
| tempOut = new DataOutputStream(new FileOutputStream(tempFile)); |
| tempOut.writeShort(SOI); |
| } |
| |
| tempOut.writeShort(marker); |
| tempOut.writeShort(length); |
| |
| byte[] header = new byte[length - 2]; |
| din.read(header); |
| tempOut.write(header); |
| } else { |
| din.skip(length - 2); |
| } |
| } |
| pos += length; |
| |
| marker = din.readShort(); |
| pos += 2; |
| } |
| |
| if (tempOut != null) { |
| // Write empty image data. |
| tempOut.writeShort(SOS); |
| // Write the frame size as 2. Since this includes the size bytes as well |
| // (short = 2 bytes), it implies there is 0 byte of image data. |
| tempOut.writeShort(2); |
| |
| // End of input |
| tempOut.writeShort(EOI); |
| tempOut.close(); |
| |
| return readRotation(tempFile.getAbsolutePath()); |
| } |
| } |
| } catch (IOException e) { |
| if (DEBUG) { |
| Log.d(TAG, "Error parsing input stream", e); |
| } |
| } finally { |
| Utils.closeSilently(in); |
| Utils.closeSilently(tempOut); |
| if (tempFile != null) { |
| tempFile.delete(); |
| } |
| } |
| return 0; |
| } |
| |
| /** |
| * Parses the rotation of the JPEG image. |
| */ |
| public static final int readRotation(String filePath) { |
| try { |
| ExifInterface exif = new ExifInterface(filePath); |
| switch (exif.getAttributeInt(ExifInterface.TAG_ORIENTATION, 0)) { |
| case ExifInterface.ORIENTATION_ROTATE_90: |
| return 90; |
| case ExifInterface.ORIENTATION_ROTATE_270: |
| return 270; |
| case ExifInterface.ORIENTATION_ROTATE_180: |
| return 180; |
| default: |
| return 0; |
| } |
| } catch (IOException e) { |
| if (DEBUG) { |
| Log.d(TAG, "Error reading file", e); |
| } |
| } |
| return 0; |
| } |
| } |