/**
* @author : Paul Taylor
*
* Version @version:$Id: ImageFormats.java 924 2010-10-18 09:52:40Z paultaylor $
*
* MusicTag Copyright (C)2003,2004
*
* This library is free software; you can redistribute it and/or modify it under the terms of the GNU Lesser
* General Public License as published by the Free Software Foundation; either version 2.1 of the License,
* or (at your option) any later version.
*
* This library is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY; without even
* the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.
* See the GNU Lesser General Public License for more details.
*
* You should have received a copy of the GNU Lesser General Public License along with this library; if not,
* you can get a copy from http://www.opensource.org/licenses/lgpl-license.php or write to the Free Software
* Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
*
* Description:
* This class maps from v2.2 Image formats (PIC) to v2.3/v2.4 Mimetypes (APIC) and
* vice versa.
*/
package org.jaudiotagger.tag.id3.valuepair;
import java.util.HashMap;
import java.util.Map;
/**
* Represents common image formats support by ID3 and provides a mapping between the format field supported in ID3v22 and the
* mimetype field supported by ID3v23/ID3v24.
*
*
* Note only JPG and PNG are mentioned specifically in the ID3 v22 Spec but it only says 'Image Format is preferably
* PNG or JPG' , not mandatory. In the jaudiotagger library we also consider GIF as a portable format, and we recognise
* BMP,PDF and TIFF but do not consider these formats as portable.
*
*/
//TODO identifying PICT, bit more difficult because in certain formats has an empty 512byte header
public class ImageFormats
{
public static final String V22_JPG_FORMAT = "JPG";
public static final String V22_PNG_FORMAT = "PNG";
public static final String V22_GIF_FORMAT = "GIF";
public static final String V22_BMP_FORMAT = "BMP";
public static final String V22_TIF_FORMAT = "TIF";
public static final String V22_PDF_FORMAT = "PDF";
public static final String V22_PIC_FORMAT = "PIC";
public static final String MIME_TYPE_JPEG = "image/jpeg";
public static final String MIME_TYPE_PNG = "image/png";
public static final String MIME_TYPE_GIF = "image/gif";
public static final String MIME_TYPE_BMP = "image/bmp";
public static final String MIME_TYPE_TIFF = "image/tiff";
public static final String MIME_TYPE_PDF = "image/pdf";
public static final String MIME_TYPE_PICT = "image/x-pict";
/**
* Sometimes this is used for jpg instead :or have I made this up
*/
public static final String MIME_TYPE_JPG = "image/jpg";
private static Map<String, String> imageFormatsToMimeType = new HashMap<String, String>();
private static Map<String, String> imageMimeTypeToFormat = new HashMap <String, String>();
static
{
imageFormatsToMimeType.put(V22_JPG_FORMAT, MIME_TYPE_JPEG);
imageFormatsToMimeType.put(V22_PNG_FORMAT, MIME_TYPE_PNG);
imageFormatsToMimeType.put(V22_GIF_FORMAT, MIME_TYPE_GIF);
imageFormatsToMimeType.put(V22_BMP_FORMAT, MIME_TYPE_BMP);
imageFormatsToMimeType.put(V22_TIF_FORMAT, MIME_TYPE_TIFF);
imageFormatsToMimeType.put(V22_PDF_FORMAT, MIME_TYPE_PDF);
imageFormatsToMimeType.put(V22_PIC_FORMAT, MIME_TYPE_PICT);
String value;
for (String key : imageFormatsToMimeType.keySet())
{
value = imageFormatsToMimeType.get(key);
imageMimeTypeToFormat.put(value, key);
}
//The mapping isn't one-one lets add other mimetypes
imageMimeTypeToFormat.put(MIME_TYPE_JPG, V22_JPG_FORMAT);
}
/**
* Get v2.3 mimetype from v2.2 format
* @param format
* @return
*/
public static String getMimeTypeForFormat(String format)
{
return imageFormatsToMimeType.get(format);
}
/**
* Get v2.2 format from v2.3 mimetype
* @param mimeType
* @return
*/
public static String getFormatForMimeType(String mimeType)
{
return imageMimeTypeToFormat.get(mimeType);
}
/**
* Is this binary data a png image
*
* @param data
* @return true if binary data matches expected header for a png
*/
public static boolean binaryDataIsPngFormat(byte[] data)
{
//Read signature
if(data.length<4)
{
return false;
}
return (0x89 == (data[0] & 0xff)) && (0x50 == (data[1] & 0xff)) && (0x4E == (data[2] & 0xff)) && (0x47 == (data[3] & 0xff));
}
/**
* Is this binary data a jpg image
*
* @param data
* @return true if binary data matches expected header for a jpg
*
* Some details http://www.obrador.com/essentialjpeg/headerinfo.htm
*/
public static boolean binaryDataIsJpgFormat(byte[] data)
{
if(data.length<4)
{
return false;
}
//Read signature
//Can be FF D8 FF E0 or FF D8 FF E1
//FF D8 is SOI Marker, FFE0 or FFE1 is JFIF Marker
return (0xff == (data[0] & 0xff)) && (0xd8 == (data[1] & 0xff)) && (0xff == (data[2] & 0xff)) && (0xe0 <= (data[3] & 0xff));
}
/**
* Is this binary data a gif image
*
* @param data
* @return true if binary data matches expected header for a gif
*/
public static boolean binaryDataIsGifFormat(byte[] data)
{
if(data.length<3)
{
return false;
}
//Read signature
return (0x47 == (data[0] & 0xff)) && (0x49 == (data[1] & 0xff)) && (0x46 == (data[2] & 0xff));
}
/**
*
* Is this binary data a bmp image
*
* @param data
* @return true if binary data matches expected header for a bmp
*/
public static boolean binaryDataIsBmpFormat(byte[] data)
{
//Read signature
return (0x42 == (data[0] & 0xff)) && (0x4d == (data[1] & 0xff));
}
/**
* Is this binary data a pdf image
*
* Details at http://en.wikipedia.org/wiki/Magic_number_%28programming%29
*
* @param data
* @return true if binary data matches expected header for a pdf
*/
public static boolean binaryDataIsPdfFormat(byte[] data)
{
//Read signature
return (0x25 == (data[0] & 0xff)) && (0x50 == (data[1] & 0xff)) && (0x44 == (data[2] & 0xff)) && (0x46 == (data[3] & 0xff));
}
/**
* is this binary data a tiff image
*
* Details at http://en.wikipedia.org/wiki/Magic_number_%28programming%29
* @param data
* @return true if binary data matches expected header for a tiff
*/
public static boolean binaryDataIsTiffFormat(byte[] data)
{
//Read signature Intel
return (
((0x49 == (data[0] & 0xff)) && (0x49 == (data[1] & 0xff)) && (0x2a == (data[2] & 0xff)) && (0x00 == (data[3] & 0xff)))
||
((0x4d == (data[0] & 0xff)) && (0x4d == (data[1] & 0xff)) && (0x00 == (data[2] & 0xff)) && (0x2a == (data[3] & 0xff)))
);
}
/**
*
* @param data
* @return true if the image format is a portable format recognised across operating systems
*/
public static boolean isPortableFormat(byte[] data)
{
return binaryDataIsPngFormat(data) || binaryDataIsJpgFormat(data) || binaryDataIsGifFormat(data);
}
/**
*
* @param data
* @return correct mimetype for the image data represented by this byte data
*/
public static String getMimeTypeForBinarySignature(byte[] data)
{
if(binaryDataIsPngFormat(data))
{
return MIME_TYPE_PNG;
}
else if(binaryDataIsJpgFormat(data))
{
return MIME_TYPE_JPEG;
}
else if(binaryDataIsGifFormat(data))
{
return MIME_TYPE_GIF;
}
else if(binaryDataIsBmpFormat(data))
{
return MIME_TYPE_BMP;
}
else if(binaryDataIsPdfFormat(data))
{
return MIME_TYPE_PDF;
}
else if(binaryDataIsTiffFormat(data))
{
return MIME_TYPE_TIFF;
}
else
{
return null;
}
}
}
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