I tried adding custom entries in the exif dictionaries I received from an image. This didn't work. I'm assuming this is due to the fact exif is a standard that is already defined.
Basically I am trying to create a metadata tag that can be placed in jpegs that will have no character limit.
I read that XMP metadata tags do not have character limits. Is this true? If so how would I create these on the iPhone?
Thank you.
I'm not sure what you've all tried code wise, but Caffeinated Cocoa has a pretty good blog entry on Image Metadata that I've used in an application for a client a while ago that might help you.
Also, the SO post Problem setting exif data for an image looks like it references the Caffeinated Cocoa. Although this question is a little over a year old, it still might help.
Try giving these a shot.
Related
Let us say I have an application that has a bunch of text and image data. It there a way to then convert the strings and images within my application into PDF format which I could then email?
What would be the best approach to this?
With such a general question, it's hard to answer with anything that isn't more or less a repetition of what Apple's docs say: Generating PDF Content
Apple's support docs are pretty good on this. The gist of it is you want to create a pdf graphics context CGPDFContext and then draw to it. The wierdest thing is that you have to flip the y axis on your drawings to PDF because iOS and Core Graphics use different origins for the axis. All this is explained in the apple docs though. If you have any specific questions, I'm new to developing and stack overflow, but I'd be happy to help you out.
If you want to see how my app writes PDF, check out Photo Logger in the app store.
I'm trying to read XMP information from a jpeg on iPhone.
I can get tags from IPTC, TIFF or EXIF easily using ImageIO but not XMP. I'm specially interested the rating tag.
Does anyone know how to do that?
I've been trying to figure this out myself for a bit. Based on what I've found it looks like a you will need to create or find a custom toolset for parsing the XMP data. It is stored in an XML format. Adobe has an SDK and toolset for dealing with XMP data that can be found here. If you look into that there was an error in the compilation instructions for the SDK in XCode. You can get a correction here on there forums.
You can also find the adobe XMP specification documents here
I still haven't gotten very deep into the rabbit hole of this topic yet myself but since no one else was responding here I thought I'd give you what little I've been able to dig up on the topic.
Hope You all are fine and also in one of your best of moods!!
Hope You all are Enjoying iPhone development.
I herewith one issue that i am not able to solve, may be i don't know the depth concept of iPhone.
So Its my humble requet to you to guide me or suggest or share your ideas.
I do find an issue with getting an image from Bytes array.
I am calling a webservice which returns an image in form of Bytes Array as response.
I have Converted this bytes array in to form of NSData, Now i have NSData, But When i Try to get an image from this NSData, It shows nil.
I Did lots of R&D and Find one suggestion to use base64 encoder, But unfortunately because of not proper guidance I was not able to Implement that.
I was also suggested to use OPenSSL Library for base64 from url http://www.cocoadev.com/index.pl?BaseSixtyFour
But again i was not able to include #include #include these two files. as in Newer Version of SDK 3.X family Apple has depreciated those (as i guess).
So Now i need help from you guys. kindly help me if you have solution or if you know the steps to solve these.
Looking Forwards.
Regards,
Arun Thakkar
Using OpenSSL on the iPhone seems like a very heavy-weight solution if all you need is Base64 encoding/decoding. Look at this post for how to use a category for NSData to add base64 encoding/decoding. You want the second section of this blog post as the first deals with OpenSSL :)
base64-encoding-options-on-mac-and-iphone
Does anyone know of a good explanation of EXIF key names? I am writing a photo organizer and want to get as much information as possible out of the photo as I can.
However, the EXIF key names are not very helpful. For example, from what I can tell (by exporting images from iPhoto)
album or set name is stored as 'fixture_identifier'
tags or keywords are stored as either 'keywords' or 'subject'
And so on.
Anyone have some valuable insight in this area?
Here is a list of EXIF tags:
https://sno.phy.queensu.ca/~phil/exiftool/TagNames/EXIF.html
Thing is that you cannot be sure of what a camera or application will put in each, so you'll have to create code to handle those corner cases (where tags or keywords are in either keywords or subject).
Also, there are maker specific tags, as you can see in the tag id 0x927c, which you should also handle specifically.
All listed here:
http://www.awaresystems.be/imaging/tiff/tifftags/privateifd/exif.html
The exiv2 library has a list of EXIF tags, see http://www.exiv2.org/tags.html
Im using a library for extracting EXIF data from google code.
I assume with iPhone OS 3 that you can use UIImagepicker to do it.
I just want to be able to extract the f-Stop, Shutter Speed and ISO data from the image.
I want to discard the image and just use the information that I store up.
Would I end up extracting the tag data in the viewcontroller.m or h?
This part of coding seems to baffle me a little bit and I cant figure out what to put where.
Can anyone help me out? I still havent figured out XCode all that well.
Whatever executable code you have needs to go in a .m (implementation) file, not a .h (header file). The headers are just for declaring things like classes, protocols, and methods, not for any real processing work.
Are there any tutorials that you know of that explain using exif step by step?
im using the one found here -
http://iphone-land.blogspot.com/2008/06/geo-tagging-images-using-iphone-exif.html
However, for a newbie like me, its not all that thorough because im coming up with errors and i am not sure how to resolve them.
I guess im just shy in all this. need a good place to start
You will likely have trouble getting access to an images metadata if you get it via UIImagePickerController, due to the issues described in this question: UIImagePickerController and extracting EXIF data from existing photos