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Android App: Image Histogram Generator

It’s time for another new Android app! My first photography app was for astrophotography. This time I wrote one that generates histograms of pretty much any sized jpeg, gif. png, or bmp you can throw at it.

Here is a link to the app on the Android Market.

Check out the video I made (Pentax K-5 at 720p 30fps, edited in Kdenlive)

As with a lot of my apps, this started with a need that I saw for myself. I wanted to be able to have nice large histograms of my camera images. I also wanted to be able to see histograms of photos I downloaded on my phone or copied over by hand.

The app description from the market page:

Check the exposure of your images on Android with this histogram generator!

Are you interested in checking out your jpeg, png, bmp, and gif files to see if they are properly exposed? It’s easy with this image histogram generator. This application loads those formats in any size, large or small, and allows you to see how luminance and color data is distributed throughout the image.

I wrote this program so that I could get a nice large detailed tonal histogram of my camera photos as well as images that I downloaded or store on the device. I was even able to display a histogram of an 8MB 100% quality JPEG from my 16MP camera! (with some wait time for processing of course).

The application allows you to select an image from the built-in android gallery as well as browse your device with any attached storage like a Micro SD card inserted into your phone or other device.

So now you and I can check our work afterward to make sure that the exposure is technically correct as well as check for either red, green, or blue color issues with a nice large full-screen graph of all four. Sometimes only one channel like red can be underexposed or over exposed, causing an issue with the overall photo. I use this program to check for difficult-to-spot issues like that.

I’m offering this up on the Android market to help others benefit from my efforts in solving a problem I had.

Fun times indeed. This was probably one of the more time intensive apps to write, taking around a full-time week and a half (pretty expensive in “developer dollars”). I have more ideas for photography apps, but I need to re-focus my attention toward a large project I’ve been working on for a few months that’s unrelated to photography and market apps. I’d like to eventually write apps for the Apple marketplace, but the cost of entry is way too much for me at the moment (developer fees plus the cost of a Mac for development and a few hardware devices for testing).

I hope some of you find this new app useful.