B4A Library JpegUtils library gives access to Exif data

This library contains an ExifData object that allows you to read and write the EXIF data in a Jpeg file. It is a very thin wrapper over the Android ExifInterface class.

 

[bluedude]

That sounds awesome, could mean I can write GPS stuff to the images taken with the camera.

 

[Erel]

Thank you! The documentation is online: Basic4android - JpegUtils

 

[mkvidyashankar]

I am trying to save some description to jpg exif data. What is the tag to save description ?

 

[praetor100]

Hi agraham,

I'm also would like to save descriptions into jpg exif data. Please could you add this meta tag in your library?

Thank you and best regards
praetor

 

[agraham]

All the tags available in Android are already exposed by this library.

ExifInterface | Android Developers

 

[praetor100]

OK, I understand. Is there a way to write IPTC tags? Some apps can this do (i.e. MoPhotos)

kind regards
praetor

 

[agraham]

You will have to roll your own in code or find a Java library to wrap.

 

[gadgetmonster]

Exif data always blank

Hi All

I'm having issues getting to the exif data using this library and could really do with some help please.

I use the contentchooser to allow the user to pic a photo from the camera. Once selected I end up in

imageChooser_Result (Success As Boolean, Dir As String, FileName As String)

Which gives me the directory and filename. As a simple test I then do:

exif.Initialize(Dir, FileName)
Dim temp As String
temp = exif.getAttribute(exif.TAG_DATETIME)

But temp is always blank. I don't get any exceptions either.

Any ideas?

 

[gadgetmonster]

Just to add, I have copied the images from my device onto my PC to verify that exif data is present and it is. My camera images b y default are stored on my SD card so I have also copied them onto the device itself and still no joy.

When returning from the content chooser, Dir = ContentDir and the Filename = content://media/external/images/media/3425 which is odd as this is not the actual name of the jpg when viewing in windows. Could this be the problem and if so how to get the correct filename.

Thanks in advance

 

[agraham]

Run the JpegUtils demo and check that the date is shown in the message box that shows when you tap the picture. A blank date may be a sign that the filename or directory is not valid. For some reason the Android ExifInterface object, which this library wraps, does not throw an Exception when initialised with an non-existent file. The initialiser for ExifInterface takes a full path (Android is not very consistent with filenames and paths) which is done like this.

exif = new ExifInterface(dir + "/" + filename);

Log your directory and filename and see what they look like.

 

[agraham]

From the help for ContentChooser

Note that these values may point to resources other than regular files. Still you can pass them to methods that expect Dir and FileName.

Looks like you need to do some string manipulation.

 

[Swissmade]

Copy Image to new resized Image with EXIF data

Hi all,

I wondering, if it is possible, to copy the old EXIF data to the new resized Image.
I have try this but then you must copy Tag for Tag.

Is there an other way to do this.

To explain this better
I take a Picture with my Camera save as "1.jpg"
Then I resize the Image to about 800x600
Save this Image as "2.jpg"
In "1.jpg" I still have the EXIF data and "2.jpg" has no EXIF data.

Many thanks for any help.:sign0163:

 

[agraham]

Is there an other way to do this.

Not with this library or within the Android API. You would need to wrap some code like metadata-extractor in a library.

 

[Swissmade]

Not with this library or within the Android API. You would need to wrap some code like metadata-extractor in a library.

Thanks for the answer,

I think I have to search for a different way.

Cheers

 

[corvo]

Help whit lat and lon

Hi, i have some problem to extract gps coordinates from a jpeg, whit the command

dim test as string

test=exif.getAttribute(exif.TAG_GPS_LATITUDE_REF)

my string contain on a letter: "N", and if i use

dim test as string

test=exif.getAttribute(exif.TAG_GPS_LATITUDE)

my string is made by strange value, like 150/569.456/1452N

how i can take the coords whit your library?

:sign0104::sign0104:

 

[Erel]

Can you post the exact string?

 

[corvo]

Thank you erel, this is the string

56/1,16973828/65539,393216/1795N

and i got also problem if i try to save the exif data in a string, i need a example :sign0104:

 

[agraham]

Here is the format of the GPS Exif tags.

TIFF Tag Reference, GPS Tags

By following the links you will see Latitude and Longitude are expressed as three rational numbers.

three RATIONAL values giving the degrees, minutes, and seconds, respectively. If latitude is expressed as degrees, minutes and seconds, a typical format would be dd/1,mm/1,ss/1. When degrees and minutes are used and, for example, fractions of minutes are given up to two decimal places, the format would be dd/1,mmmm/100,0/1.

 

[corvo]

Thank you, but i need the value in grades ( fox example 38,5448521455895), how i can convert it? another question whit exif i tried to set the lat lon coordinates in a pic, but it don't works

Dim fname As String
fname = "bb.jpg"
exif.Initialize(File.DirRootExternal, fname)

exif.setAttribute(exif.TAG_GPS_LATITUDE,"78.4879874897979")
exif.setAttribute(exif.TAG_GPS_LONGITUDE,"25.62541525855")
exif.saveAttributes

whitout a clear example is very hard for me to undestand, cause i'm not a expert thenk you