19323b13fc9bc79ce38ce7c851a2aa894ab988ed0Paul Westbrook/* 29323b13fc9bc79ce38ce7c851a2aa894ab988ed0Paul Westbrook * Copyright (C) 2010 The Android Open Source Project 39323b13fc9bc79ce38ce7c851a2aa894ab988ed0Paul Westbrook * 49323b13fc9bc79ce38ce7c851a2aa894ab988ed0Paul Westbrook * Licensed under the Apache License, Version 2.0 (the "License"); 59323b13fc9bc79ce38ce7c851a2aa894ab988ed0Paul Westbrook * you may not use this file except in compliance with the License. 69323b13fc9bc79ce38ce7c851a2aa894ab988ed0Paul Westbrook * You may obtain a copy of the License at 79323b13fc9bc79ce38ce7c851a2aa894ab988ed0Paul Westbrook * 89323b13fc9bc79ce38ce7c851a2aa894ab988ed0Paul Westbrook * http://www.apache.org/licenses/LICENSE-2.0 99323b13fc9bc79ce38ce7c851a2aa894ab988ed0Paul Westbrook * 109323b13fc9bc79ce38ce7c851a2aa894ab988ed0Paul Westbrook * Unless required by applicable law or agreed to in writing, software 119323b13fc9bc79ce38ce7c851a2aa894ab988ed0Paul Westbrook * distributed under the License is distributed on an "AS IS" BASIS, 129323b13fc9bc79ce38ce7c851a2aa894ab988ed0Paul Westbrook * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. 139323b13fc9bc79ce38ce7c851a2aa894ab988ed0Paul Westbrook * See the License for the specific language governing permissions and 149323b13fc9bc79ce38ce7c851a2aa894ab988ed0Paul Westbrook * limitations under the License. 159323b13fc9bc79ce38ce7c851a2aa894ab988ed0Paul Westbrook */ 169323b13fc9bc79ce38ce7c851a2aa894ab988ed0Paul Westbrook 179323b13fc9bc79ce38ce7c851a2aa894ab988ed0Paul Westbrookpackage com.android.ex.photo.util; 189323b13fc9bc79ce38ce7c851a2aa894ab988ed0Paul Westbrook 199323b13fc9bc79ce38ce7c851a2aa894ab988ed0Paul Westbrookimport android.util.Log; 209323b13fc9bc79ce38ce7c851a2aa894ab988ed0Paul Westbrook 219323b13fc9bc79ce38ce7c851a2aa894ab988ed0Paul Westbrookpublic class Exif { 229323b13fc9bc79ce38ce7c851a2aa894ab988ed0Paul Westbrook private static final String TAG = "CameraExif"; 239323b13fc9bc79ce38ce7c851a2aa894ab988ed0Paul Westbrook 249323b13fc9bc79ce38ce7c851a2aa894ab988ed0Paul Westbrook // Returns the degrees in clockwise. Values are 0, 90, 180, or 270. 259323b13fc9bc79ce38ce7c851a2aa894ab988ed0Paul Westbrook public static int getOrientation(byte[] jpeg) { 269323b13fc9bc79ce38ce7c851a2aa894ab988ed0Paul Westbrook if (jpeg == null) { 279323b13fc9bc79ce38ce7c851a2aa894ab988ed0Paul Westbrook return 0; 289323b13fc9bc79ce38ce7c851a2aa894ab988ed0Paul Westbrook } 299323b13fc9bc79ce38ce7c851a2aa894ab988ed0Paul Westbrook 309323b13fc9bc79ce38ce7c851a2aa894ab988ed0Paul Westbrook int offset = 0; 319323b13fc9bc79ce38ce7c851a2aa894ab988ed0Paul Westbrook int length = 0; 329323b13fc9bc79ce38ce7c851a2aa894ab988ed0Paul Westbrook 339323b13fc9bc79ce38ce7c851a2aa894ab988ed0Paul Westbrook // ISO/IEC 10918-1:1993(E) 349323b13fc9bc79ce38ce7c851a2aa894ab988ed0Paul Westbrook while (offset + 3 < jpeg.length && (jpeg[offset++] & 0xFF) == 0xFF) { 359323b13fc9bc79ce38ce7c851a2aa894ab988ed0Paul Westbrook int marker = jpeg[offset] & 0xFF; 369323b13fc9bc79ce38ce7c851a2aa894ab988ed0Paul Westbrook 379323b13fc9bc79ce38ce7c851a2aa894ab988ed0Paul Westbrook // Check if the marker is a padding. 389323b13fc9bc79ce38ce7c851a2aa894ab988ed0Paul Westbrook if (marker == 0xFF) { 399323b13fc9bc79ce38ce7c851a2aa894ab988ed0Paul Westbrook continue; 409323b13fc9bc79ce38ce7c851a2aa894ab988ed0Paul Westbrook } 419323b13fc9bc79ce38ce7c851a2aa894ab988ed0Paul Westbrook offset++; 429323b13fc9bc79ce38ce7c851a2aa894ab988ed0Paul Westbrook 439323b13fc9bc79ce38ce7c851a2aa894ab988ed0Paul Westbrook // Check if the marker is SOI or TEM. 449323b13fc9bc79ce38ce7c851a2aa894ab988ed0Paul Westbrook if (marker == 0xD8 || marker == 0x01) { 459323b13fc9bc79ce38ce7c851a2aa894ab988ed0Paul Westbrook continue; 469323b13fc9bc79ce38ce7c851a2aa894ab988ed0Paul Westbrook } 479323b13fc9bc79ce38ce7c851a2aa894ab988ed0Paul Westbrook // Check if the marker is EOI or SOS. 489323b13fc9bc79ce38ce7c851a2aa894ab988ed0Paul Westbrook if (marker == 0xD9 || marker == 0xDA) { 499323b13fc9bc79ce38ce7c851a2aa894ab988ed0Paul Westbrook break; 509323b13fc9bc79ce38ce7c851a2aa894ab988ed0Paul Westbrook } 519323b13fc9bc79ce38ce7c851a2aa894ab988ed0Paul Westbrook 529323b13fc9bc79ce38ce7c851a2aa894ab988ed0Paul Westbrook // Get the length and check if it is reasonable. 539323b13fc9bc79ce38ce7c851a2aa894ab988ed0Paul Westbrook length = pack(jpeg, offset, 2, false); 549323b13fc9bc79ce38ce7c851a2aa894ab988ed0Paul Westbrook if (length < 2 || offset + length > jpeg.length) { 559323b13fc9bc79ce38ce7c851a2aa894ab988ed0Paul Westbrook Log.e(TAG, "Invalid length"); 569323b13fc9bc79ce38ce7c851a2aa894ab988ed0Paul Westbrook return 0; 579323b13fc9bc79ce38ce7c851a2aa894ab988ed0Paul Westbrook } 589323b13fc9bc79ce38ce7c851a2aa894ab988ed0Paul Westbrook 599323b13fc9bc79ce38ce7c851a2aa894ab988ed0Paul Westbrook // Break if the marker is EXIF in APP1. 609323b13fc9bc79ce38ce7c851a2aa894ab988ed0Paul Westbrook if (marker == 0xE1 && length >= 8 && 619323b13fc9bc79ce38ce7c851a2aa894ab988ed0Paul Westbrook pack(jpeg, offset + 2, 4, false) == 0x45786966 && 629323b13fc9bc79ce38ce7c851a2aa894ab988ed0Paul Westbrook pack(jpeg, offset + 6, 2, false) == 0) { 639323b13fc9bc79ce38ce7c851a2aa894ab988ed0Paul Westbrook offset += 8; 649323b13fc9bc79ce38ce7c851a2aa894ab988ed0Paul Westbrook length -= 8; 659323b13fc9bc79ce38ce7c851a2aa894ab988ed0Paul Westbrook break; 669323b13fc9bc79ce38ce7c851a2aa894ab988ed0Paul Westbrook } 679323b13fc9bc79ce38ce7c851a2aa894ab988ed0Paul Westbrook 689323b13fc9bc79ce38ce7c851a2aa894ab988ed0Paul Westbrook // Skip other markers. 699323b13fc9bc79ce38ce7c851a2aa894ab988ed0Paul Westbrook offset += length; 709323b13fc9bc79ce38ce7c851a2aa894ab988ed0Paul Westbrook length = 0; 719323b13fc9bc79ce38ce7c851a2aa894ab988ed0Paul Westbrook } 729323b13fc9bc79ce38ce7c851a2aa894ab988ed0Paul Westbrook 739323b13fc9bc79ce38ce7c851a2aa894ab988ed0Paul Westbrook // JEITA CP-3451 Exif Version 2.2 749323b13fc9bc79ce38ce7c851a2aa894ab988ed0Paul Westbrook if (length > 8) { 759323b13fc9bc79ce38ce7c851a2aa894ab988ed0Paul Westbrook // Identify the byte order. 769323b13fc9bc79ce38ce7c851a2aa894ab988ed0Paul Westbrook int tag = pack(jpeg, offset, 4, false); 779323b13fc9bc79ce38ce7c851a2aa894ab988ed0Paul Westbrook if (tag != 0x49492A00 && tag != 0x4D4D002A) { 789323b13fc9bc79ce38ce7c851a2aa894ab988ed0Paul Westbrook Log.e(TAG, "Invalid byte order"); 799323b13fc9bc79ce38ce7c851a2aa894ab988ed0Paul Westbrook return 0; 809323b13fc9bc79ce38ce7c851a2aa894ab988ed0Paul Westbrook } 819323b13fc9bc79ce38ce7c851a2aa894ab988ed0Paul Westbrook boolean littleEndian = (tag == 0x49492A00); 829323b13fc9bc79ce38ce7c851a2aa894ab988ed0Paul Westbrook 839323b13fc9bc79ce38ce7c851a2aa894ab988ed0Paul Westbrook // Get the offset and check if it is reasonable. 849323b13fc9bc79ce38ce7c851a2aa894ab988ed0Paul Westbrook int count = pack(jpeg, offset + 4, 4, littleEndian) + 2; 859323b13fc9bc79ce38ce7c851a2aa894ab988ed0Paul Westbrook if (count < 10 || count > length) { 869323b13fc9bc79ce38ce7c851a2aa894ab988ed0Paul Westbrook Log.e(TAG, "Invalid offset"); 879323b13fc9bc79ce38ce7c851a2aa894ab988ed0Paul Westbrook return 0; 889323b13fc9bc79ce38ce7c851a2aa894ab988ed0Paul Westbrook } 899323b13fc9bc79ce38ce7c851a2aa894ab988ed0Paul Westbrook offset += count; 909323b13fc9bc79ce38ce7c851a2aa894ab988ed0Paul Westbrook length -= count; 919323b13fc9bc79ce38ce7c851a2aa894ab988ed0Paul Westbrook 929323b13fc9bc79ce38ce7c851a2aa894ab988ed0Paul Westbrook // Get the count and go through all the elements. 939323b13fc9bc79ce38ce7c851a2aa894ab988ed0Paul Westbrook count = pack(jpeg, offset - 2, 2, littleEndian); 949323b13fc9bc79ce38ce7c851a2aa894ab988ed0Paul Westbrook while (count-- > 0 && length >= 12) { 959323b13fc9bc79ce38ce7c851a2aa894ab988ed0Paul Westbrook // Get the tag and check if it is orientation. 969323b13fc9bc79ce38ce7c851a2aa894ab988ed0Paul Westbrook tag = pack(jpeg, offset, 2, littleEndian); 979323b13fc9bc79ce38ce7c851a2aa894ab988ed0Paul Westbrook if (tag == 0x0112) { 989323b13fc9bc79ce38ce7c851a2aa894ab988ed0Paul Westbrook // We do not really care about type and count, do we? 999323b13fc9bc79ce38ce7c851a2aa894ab988ed0Paul Westbrook int orientation = pack(jpeg, offset + 8, 2, littleEndian); 1009323b13fc9bc79ce38ce7c851a2aa894ab988ed0Paul Westbrook switch (orientation) { 1019323b13fc9bc79ce38ce7c851a2aa894ab988ed0Paul Westbrook case 1: 1029323b13fc9bc79ce38ce7c851a2aa894ab988ed0Paul Westbrook return 0; 1039323b13fc9bc79ce38ce7c851a2aa894ab988ed0Paul Westbrook case 3: 1049323b13fc9bc79ce38ce7c851a2aa894ab988ed0Paul Westbrook return 180; 1059323b13fc9bc79ce38ce7c851a2aa894ab988ed0Paul Westbrook case 6: 1069323b13fc9bc79ce38ce7c851a2aa894ab988ed0Paul Westbrook return 90; 1079323b13fc9bc79ce38ce7c851a2aa894ab988ed0Paul Westbrook case 8: 1089323b13fc9bc79ce38ce7c851a2aa894ab988ed0Paul Westbrook return 270; 1099323b13fc9bc79ce38ce7c851a2aa894ab988ed0Paul Westbrook } 1109323b13fc9bc79ce38ce7c851a2aa894ab988ed0Paul Westbrook Log.i(TAG, "Unsupported orientation"); 1119323b13fc9bc79ce38ce7c851a2aa894ab988ed0Paul Westbrook return 0; 1129323b13fc9bc79ce38ce7c851a2aa894ab988ed0Paul Westbrook } 1139323b13fc9bc79ce38ce7c851a2aa894ab988ed0Paul Westbrook offset += 12; 1149323b13fc9bc79ce38ce7c851a2aa894ab988ed0Paul Westbrook length -= 12; 1159323b13fc9bc79ce38ce7c851a2aa894ab988ed0Paul Westbrook } 1169323b13fc9bc79ce38ce7c851a2aa894ab988ed0Paul Westbrook } 1179323b13fc9bc79ce38ce7c851a2aa894ab988ed0Paul Westbrook 1189323b13fc9bc79ce38ce7c851a2aa894ab988ed0Paul Westbrook Log.i(TAG, "Orientation not found"); 1199323b13fc9bc79ce38ce7c851a2aa894ab988ed0Paul Westbrook return 0; 1209323b13fc9bc79ce38ce7c851a2aa894ab988ed0Paul Westbrook } 1219323b13fc9bc79ce38ce7c851a2aa894ab988ed0Paul Westbrook 1229323b13fc9bc79ce38ce7c851a2aa894ab988ed0Paul Westbrook private static int pack(byte[] bytes, int offset, int length, 1239323b13fc9bc79ce38ce7c851a2aa894ab988ed0Paul Westbrook boolean littleEndian) { 1249323b13fc9bc79ce38ce7c851a2aa894ab988ed0Paul Westbrook int step = 1; 1259323b13fc9bc79ce38ce7c851a2aa894ab988ed0Paul Westbrook if (littleEndian) { 1269323b13fc9bc79ce38ce7c851a2aa894ab988ed0Paul Westbrook offset += length - 1; 1279323b13fc9bc79ce38ce7c851a2aa894ab988ed0Paul Westbrook step = -1; 1289323b13fc9bc79ce38ce7c851a2aa894ab988ed0Paul Westbrook } 1299323b13fc9bc79ce38ce7c851a2aa894ab988ed0Paul Westbrook 1309323b13fc9bc79ce38ce7c851a2aa894ab988ed0Paul Westbrook int value = 0; 1319323b13fc9bc79ce38ce7c851a2aa894ab988ed0Paul Westbrook while (length-- > 0) { 1329323b13fc9bc79ce38ce7c851a2aa894ab988ed0Paul Westbrook value = (value << 8) | (bytes[offset] & 0xFF); 1339323b13fc9bc79ce38ce7c851a2aa894ab988ed0Paul Westbrook offset += step; 1349323b13fc9bc79ce38ce7c851a2aa894ab988ed0Paul Westbrook } 1359323b13fc9bc79ce38ce7c851a2aa894ab988ed0Paul Westbrook return value; 1369323b13fc9bc79ce38ce7c851a2aa894ab988ed0Paul Westbrook } 1379323b13fc9bc79ce38ce7c851a2aa894ab988ed0Paul Westbrook} 138