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I have to do some stuff. I'm downloading images using web-service, after successful download of each image, I'm using "AES" encryption algorithm to encrypt that images. I'have done encryption successfully. But whenever I'm going to open Gallery of device, I am able to seen that downloaded images encrypted by me. I don't want that. I wanna secure that images that can prevent access from Gallery.

I understood the whole process here.When I am storing each image after download Gallery capture that image and store into its cache so before my encryption process may be Gallery populate that images.

-> My Encryption process : Download Image - > Store into SDCARD - > Encrypting Image - > Delete the real Image

But this is not deleting from Gallery also.

So in short I wanna secure that images that can prevent access from Gallery. Let me know your best suggestion about my process is right or wrong? May I have to do a few changes on it? or have you nice idea instead of my process ?

Thanks for your best suggestions.

Jai
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  • Have you tried downloading the image and encrypting it in memory? Consider using CipherInputStream and/or CipherOutputStream – Frohnzie Jan 24 '13 at 13:53

3 Answers3

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You must add an empty file to your images folder called .nomedia. This will prevent the MediaScanner from indexes images in that folder.

However, there is a bug on ICS that makes this slightly harder. On ICS, your folder must have the .nomedia present before you add images to it, or else the images will be indexed.

Another, slightly less compliant option is to begin your folder name with a dot (something like .foldername). As Android is UNIX based, this will make it a hidden folder, and hence not have the MediaScanner scan it.

Raghav Sood
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  • Great brother!! Thanks for your great help!! Exactly got what I need!! – Jai Jan 25 '13 at 04:45
  • I need your help!! Above 4.0, I am able to create folder .nomedia but whenever my app is going to download images, Gallery instantly fetching that images. like downloading 1..2..3.. In Gallery 1..2..3. increases. So after successful download in sdcard we are not able to seen that images but able to seen with Gallery – Jai Jan 25 '13 at 07:01
  • There is a bug in newer versions of Android about this. Make sure that the .nomedia file is present before you add any images to the folder. – Raghav Sood Jan 25 '13 at 07:19
  • Ya I have created .nomedia file before adding images to the folder.but Gallery still fetching that images instantly!!! – Jai Jan 25 '13 at 09:02
  • Is there any help for higher version? – Jai Jan 25 '13 at 10:03
  • @Jai As I mentioned in my answer, you could try adding a . to the folder name – Raghav Sood Jan 25 '13 at 10:13
  • Note that, when you connect your phone/tablet with computer then your encrypted images from SD Card is exposed or is visible. – Kartik Domadiya Jan 25 '13 at 10:25
  • @RaghavSood : Dude I have added (.) to the folder name but its not working with higher version above 4.0 – Jai Jan 25 '13 at 11:18
  • @Jai If your app was already installed on those devices, you will have to delete it completely and reinstall for this to work. That includes deleting any images you may have downloaded. – Raghav Sood Jan 25 '13 at 11:22
  • @RaghavSood : Ya I have tried it many times to unistall everything and after install again. Also reboot my device many times after deleting downloaded images everything. I have device with version 4.0.3. It's not working. Your answer is absolutely right it have to work as it is default behavior of linux based system. But don't know why it is not working. – Jai Jan 25 '13 at 11:28
  • @RaghavSood : I have solved my problem by following solution with all the versions as I have updated my answer here. Please check it and let me take your feedback on it. – Jai Jan 25 '13 at 11:29
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I have got a proper solution. That will also work with higher versions.

You can keep it private with your application's private folder using following directory :

String mDirectory = getPackageManager().getPackageInfo("com.example.myapp", 0).applicationInfo.dataDir;

You can store your private data into this package. It will prevent access as well as prevent indexing from Gallery. So you don't need to worry about it's encryption process also :) . May be this folder will not provide much space. But atleast it will be help us.

Jai
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  • Considering you are storing images in it, it will take up a lot of space. It could cause lots of users to uninstall your app. – Raghav Sood Jan 25 '13 at 11:48
  • @RaghavSood : you are right, Exactly I thought that. It may be cause problem. But it will cause problem only when you are storing high profile data. If you are going to store data with few amount of storage then of course it will not cause problem. Is it right? – Jai Jan 25 '13 at 11:51
  • Internal storage space can range from about 70MB to more than 1 GB. It is shared by all installed apps, not only for internal data, but also for their own code installation. On some devices, it runs out very quickly – Raghav Sood Jan 25 '13 at 12:02
  • @RaghavSood : Yes, brother then what we can do? :). N don't know why your solution is not working with higher versions? – Jai Jan 25 '13 at 12:13
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Sounds like below solution might work for all versions - (Storing videos, images and audio files that can not be accesses by others)

For this you have to store your data in External Storage with creating a folder name starting with the .(dot) then this folder is hidden from the FileExplorer.In this folder you need to create a .nomedia file and place your Images and video then images and videos are can not be visible to User in the Gallery.nomedia folder files can not be read by the gallery.

Community
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Jay
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