137cffb8467d1ccca719a7847582d04da36c5bc6fChia-chi Yeh/* 237cffb8467d1ccca719a7847582d04da36c5bc6fChia-chi Yeh * Copyright (C) 2010 The Android Open Source Project 337cffb8467d1ccca719a7847582d04da36c5bc6fChia-chi Yeh * 437cffb8467d1ccca719a7847582d04da36c5bc6fChia-chi Yeh * Licensed under the Apache License, Version 2.0 (the "License"); 537cffb8467d1ccca719a7847582d04da36c5bc6fChia-chi Yeh * you may not use this file except in compliance with the License. 637cffb8467d1ccca719a7847582d04da36c5bc6fChia-chi Yeh * You may obtain a copy of the License at 737cffb8467d1ccca719a7847582d04da36c5bc6fChia-chi Yeh * 837cffb8467d1ccca719a7847582d04da36c5bc6fChia-chi Yeh * http://www.apache.org/licenses/LICENSE-2.0 937cffb8467d1ccca719a7847582d04da36c5bc6fChia-chi Yeh * 1037cffb8467d1ccca719a7847582d04da36c5bc6fChia-chi Yeh * Unless required by applicable law or agreed to in writing, software 1137cffb8467d1ccca719a7847582d04da36c5bc6fChia-chi Yeh * distributed under the License is distributed on an "AS IS" BASIS, 1237cffb8467d1ccca719a7847582d04da36c5bc6fChia-chi Yeh * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. 1337cffb8467d1ccca719a7847582d04da36c5bc6fChia-chi Yeh * See the License for the specific language governing permissions and 1437cffb8467d1ccca719a7847582d04da36c5bc6fChia-chi Yeh * limitations under the License. 1537cffb8467d1ccca719a7847582d04da36c5bc6fChia-chi Yeh */ 1637cffb8467d1ccca719a7847582d04da36c5bc6fChia-chi Yeh 1737cffb8467d1ccca719a7847582d04da36c5bc6fChia-chi Yehpackage com.android.camera; 1837cffb8467d1ccca719a7847582d04da36c5bc6fChia-chi Yeh 1937cffb8467d1ccca719a7847582d04da36c5bc6fChia-chi Yehimport android.util.Log; 2037cffb8467d1ccca719a7847582d04da36c5bc6fChia-chi Yeh 21a907c122ccec649c6cedf3a45b1c426a5fca932eAngus Kongpublic class Exif { 2237cffb8467d1ccca719a7847582d04da36c5bc6fChia-chi Yeh private static final String TAG = "CameraExif"; 2337cffb8467d1ccca719a7847582d04da36c5bc6fChia-chi Yeh 24a3d2bab37e9c008e3b4c7e4ba93ba1fc40bd4b90Wu-cheng Li // Returns the degrees in clockwise. Values are 0, 90, 180, or 270. 2537cffb8467d1ccca719a7847582d04da36c5bc6fChia-chi Yeh public static int getOrientation(byte[] jpeg) { 2637cffb8467d1ccca719a7847582d04da36c5bc6fChia-chi Yeh if (jpeg == null) { 2737cffb8467d1ccca719a7847582d04da36c5bc6fChia-chi Yeh return 0; 2837cffb8467d1ccca719a7847582d04da36c5bc6fChia-chi Yeh } 2937cffb8467d1ccca719a7847582d04da36c5bc6fChia-chi Yeh 3037cffb8467d1ccca719a7847582d04da36c5bc6fChia-chi Yeh int offset = 0; 3137cffb8467d1ccca719a7847582d04da36c5bc6fChia-chi Yeh int length = 0; 3237cffb8467d1ccca719a7847582d04da36c5bc6fChia-chi Yeh 3337cffb8467d1ccca719a7847582d04da36c5bc6fChia-chi Yeh // ISO/IEC 10918-1:1993(E) 3437cffb8467d1ccca719a7847582d04da36c5bc6fChia-chi Yeh while (offset + 3 < jpeg.length && (jpeg[offset++] & 0xFF) == 0xFF) { 3537cffb8467d1ccca719a7847582d04da36c5bc6fChia-chi Yeh int marker = jpeg[offset] & 0xFF; 3637cffb8467d1ccca719a7847582d04da36c5bc6fChia-chi Yeh 3737cffb8467d1ccca719a7847582d04da36c5bc6fChia-chi Yeh // Check if the marker is a padding. 3837cffb8467d1ccca719a7847582d04da36c5bc6fChia-chi Yeh if (marker == 0xFF) { 3937cffb8467d1ccca719a7847582d04da36c5bc6fChia-chi Yeh continue; 4037cffb8467d1ccca719a7847582d04da36c5bc6fChia-chi Yeh } 4137cffb8467d1ccca719a7847582d04da36c5bc6fChia-chi Yeh offset++; 4237cffb8467d1ccca719a7847582d04da36c5bc6fChia-chi Yeh 4337cffb8467d1ccca719a7847582d04da36c5bc6fChia-chi Yeh // Check if the marker is SOI or TEM. 4437cffb8467d1ccca719a7847582d04da36c5bc6fChia-chi Yeh if (marker == 0xD8 || marker == 0x01) { 4537cffb8467d1ccca719a7847582d04da36c5bc6fChia-chi Yeh continue; 4637cffb8467d1ccca719a7847582d04da36c5bc6fChia-chi Yeh } 4737cffb8467d1ccca719a7847582d04da36c5bc6fChia-chi Yeh // Check if the marker is EOI or SOS. 4837cffb8467d1ccca719a7847582d04da36c5bc6fChia-chi Yeh if (marker == 0xD9 || marker == 0xDA) { 4937cffb8467d1ccca719a7847582d04da36c5bc6fChia-chi Yeh break; 5037cffb8467d1ccca719a7847582d04da36c5bc6fChia-chi Yeh } 5137cffb8467d1ccca719a7847582d04da36c5bc6fChia-chi Yeh 5237cffb8467d1ccca719a7847582d04da36c5bc6fChia-chi Yeh // Get the length and check if it is reasonable. 5337cffb8467d1ccca719a7847582d04da36c5bc6fChia-chi Yeh length = pack(jpeg, offset, 2, false); 5437cffb8467d1ccca719a7847582d04da36c5bc6fChia-chi Yeh if (length < 2 || offset + length > jpeg.length) { 5537cffb8467d1ccca719a7847582d04da36c5bc6fChia-chi Yeh Log.e(TAG, "Invalid length"); 5637cffb8467d1ccca719a7847582d04da36c5bc6fChia-chi Yeh return 0; 5737cffb8467d1ccca719a7847582d04da36c5bc6fChia-chi Yeh } 5837cffb8467d1ccca719a7847582d04da36c5bc6fChia-chi Yeh 5937cffb8467d1ccca719a7847582d04da36c5bc6fChia-chi Yeh // Break if the marker is EXIF in APP1. 6037cffb8467d1ccca719a7847582d04da36c5bc6fChia-chi Yeh if (marker == 0xE1 && length >= 8 && 6137cffb8467d1ccca719a7847582d04da36c5bc6fChia-chi Yeh pack(jpeg, offset + 2, 4, false) == 0x45786966 && 6237cffb8467d1ccca719a7847582d04da36c5bc6fChia-chi Yeh pack(jpeg, offset + 6, 2, false) == 0) { 6337cffb8467d1ccca719a7847582d04da36c5bc6fChia-chi Yeh offset += 8; 6437cffb8467d1ccca719a7847582d04da36c5bc6fChia-chi Yeh length -= 8; 6537cffb8467d1ccca719a7847582d04da36c5bc6fChia-chi Yeh break; 6637cffb8467d1ccca719a7847582d04da36c5bc6fChia-chi Yeh } 6737cffb8467d1ccca719a7847582d04da36c5bc6fChia-chi Yeh 6837cffb8467d1ccca719a7847582d04da36c5bc6fChia-chi Yeh // Skip other markers. 6937cffb8467d1ccca719a7847582d04da36c5bc6fChia-chi Yeh offset += length; 7037cffb8467d1ccca719a7847582d04da36c5bc6fChia-chi Yeh length = 0; 7137cffb8467d1ccca719a7847582d04da36c5bc6fChia-chi Yeh } 7237cffb8467d1ccca719a7847582d04da36c5bc6fChia-chi Yeh 7337cffb8467d1ccca719a7847582d04da36c5bc6fChia-chi Yeh // JEITA CP-3451 Exif Version 2.2 7437cffb8467d1ccca719a7847582d04da36c5bc6fChia-chi Yeh if (length > 8) { 7537cffb8467d1ccca719a7847582d04da36c5bc6fChia-chi Yeh // Identify the byte order. 7637cffb8467d1ccca719a7847582d04da36c5bc6fChia-chi Yeh int tag = pack(jpeg, offset, 4, false); 7737cffb8467d1ccca719a7847582d04da36c5bc6fChia-chi Yeh if (tag != 0x49492A00 && tag != 0x4D4D002A) { 7837cffb8467d1ccca719a7847582d04da36c5bc6fChia-chi Yeh Log.e(TAG, "Invalid byte order"); 7937cffb8467d1ccca719a7847582d04da36c5bc6fChia-chi Yeh return 0; 8037cffb8467d1ccca719a7847582d04da36c5bc6fChia-chi Yeh } 8137cffb8467d1ccca719a7847582d04da36c5bc6fChia-chi Yeh boolean littleEndian = (tag == 0x49492A00); 8237cffb8467d1ccca719a7847582d04da36c5bc6fChia-chi Yeh 8337cffb8467d1ccca719a7847582d04da36c5bc6fChia-chi Yeh // Get the offset and check if it is reasonable. 8437cffb8467d1ccca719a7847582d04da36c5bc6fChia-chi Yeh int count = pack(jpeg, offset + 4, 4, littleEndian) + 2; 8537cffb8467d1ccca719a7847582d04da36c5bc6fChia-chi Yeh if (count < 10 || count > length) { 8637cffb8467d1ccca719a7847582d04da36c5bc6fChia-chi Yeh Log.e(TAG, "Invalid offset"); 8737cffb8467d1ccca719a7847582d04da36c5bc6fChia-chi Yeh return 0; 8837cffb8467d1ccca719a7847582d04da36c5bc6fChia-chi Yeh } 8937cffb8467d1ccca719a7847582d04da36c5bc6fChia-chi Yeh offset += count; 9037cffb8467d1ccca719a7847582d04da36c5bc6fChia-chi Yeh length -= count; 9137cffb8467d1ccca719a7847582d04da36c5bc6fChia-chi Yeh 9237cffb8467d1ccca719a7847582d04da36c5bc6fChia-chi Yeh // Get the count and go through all the elements. 9337cffb8467d1ccca719a7847582d04da36c5bc6fChia-chi Yeh count = pack(jpeg, offset - 2, 2, littleEndian); 9437cffb8467d1ccca719a7847582d04da36c5bc6fChia-chi Yeh while (count-- > 0 && length >= 12) { 9537cffb8467d1ccca719a7847582d04da36c5bc6fChia-chi Yeh // Get the tag and check if it is orientation. 9637cffb8467d1ccca719a7847582d04da36c5bc6fChia-chi Yeh tag = pack(jpeg, offset, 2, littleEndian); 9737cffb8467d1ccca719a7847582d04da36c5bc6fChia-chi Yeh if (tag == 0x0112) { 9837cffb8467d1ccca719a7847582d04da36c5bc6fChia-chi Yeh // We do not really care about type and count, do we? 9937cffb8467d1ccca719a7847582d04da36c5bc6fChia-chi Yeh int orientation = pack(jpeg, offset + 8, 2, littleEndian); 10037cffb8467d1ccca719a7847582d04da36c5bc6fChia-chi Yeh switch (orientation) { 10137cffb8467d1ccca719a7847582d04da36c5bc6fChia-chi Yeh case 1: 10237cffb8467d1ccca719a7847582d04da36c5bc6fChia-chi Yeh return 0; 10337cffb8467d1ccca719a7847582d04da36c5bc6fChia-chi Yeh case 3: 10437cffb8467d1ccca719a7847582d04da36c5bc6fChia-chi Yeh return 180; 10537cffb8467d1ccca719a7847582d04da36c5bc6fChia-chi Yeh case 6: 10637cffb8467d1ccca719a7847582d04da36c5bc6fChia-chi Yeh return 90; 10737cffb8467d1ccca719a7847582d04da36c5bc6fChia-chi Yeh case 8: 10837cffb8467d1ccca719a7847582d04da36c5bc6fChia-chi Yeh return 270; 10937cffb8467d1ccca719a7847582d04da36c5bc6fChia-chi Yeh } 11037cffb8467d1ccca719a7847582d04da36c5bc6fChia-chi Yeh Log.i(TAG, "Unsupported orientation"); 11137cffb8467d1ccca719a7847582d04da36c5bc6fChia-chi Yeh return 0; 11237cffb8467d1ccca719a7847582d04da36c5bc6fChia-chi Yeh } 11337cffb8467d1ccca719a7847582d04da36c5bc6fChia-chi Yeh offset += 12; 11437cffb8467d1ccca719a7847582d04da36c5bc6fChia-chi Yeh length -= 12; 11537cffb8467d1ccca719a7847582d04da36c5bc6fChia-chi Yeh } 11637cffb8467d1ccca719a7847582d04da36c5bc6fChia-chi Yeh } 11737cffb8467d1ccca719a7847582d04da36c5bc6fChia-chi Yeh 11837cffb8467d1ccca719a7847582d04da36c5bc6fChia-chi Yeh Log.i(TAG, "Orientation not found"); 11937cffb8467d1ccca719a7847582d04da36c5bc6fChia-chi Yeh return 0; 12037cffb8467d1ccca719a7847582d04da36c5bc6fChia-chi Yeh } 12137cffb8467d1ccca719a7847582d04da36c5bc6fChia-chi Yeh 12237cffb8467d1ccca719a7847582d04da36c5bc6fChia-chi Yeh private static int pack(byte[] bytes, int offset, int length, 12337cffb8467d1ccca719a7847582d04da36c5bc6fChia-chi Yeh boolean littleEndian) { 12437cffb8467d1ccca719a7847582d04da36c5bc6fChia-chi Yeh int step = 1; 12537cffb8467d1ccca719a7847582d04da36c5bc6fChia-chi Yeh if (littleEndian) { 12637cffb8467d1ccca719a7847582d04da36c5bc6fChia-chi Yeh offset += length - 1; 12737cffb8467d1ccca719a7847582d04da36c5bc6fChia-chi Yeh step = -1; 12837cffb8467d1ccca719a7847582d04da36c5bc6fChia-chi Yeh } 12937cffb8467d1ccca719a7847582d04da36c5bc6fChia-chi Yeh 13037cffb8467d1ccca719a7847582d04da36c5bc6fChia-chi Yeh int value = 0; 13137cffb8467d1ccca719a7847582d04da36c5bc6fChia-chi Yeh while (length-- > 0) { 13237cffb8467d1ccca719a7847582d04da36c5bc6fChia-chi Yeh value = (value << 8) | (bytes[offset] & 0xFF); 13337cffb8467d1ccca719a7847582d04da36c5bc6fChia-chi Yeh offset += step; 13437cffb8467d1ccca719a7847582d04da36c5bc6fChia-chi Yeh } 13537cffb8467d1ccca719a7847582d04da36c5bc6fChia-chi Yeh return value; 13637cffb8467d1ccca719a7847582d04da36c5bc6fChia-chi Yeh } 13737cffb8467d1ccca719a7847582d04da36c5bc6fChia-chi Yeh} 138