iPhone development isn’t really all that much fun, but the end results can be very cool. Dave Mark and Jeff LaMarche have written a really nice introduction which makes the whole process seem just about manageable. Almost cool and quirky even.
Importantly, it successfully captures the key to the iPhone’s success as a development platform: anyone with sufficient determination (yes, you!) can get through the unnecessary and bizarre horrors of Objective-C and the iPhone SDK, and can produce something that people might pay some money for. It’s something you can almost impress people with at parties. Almost.
Of course the book has an online forum and downloadable source code – de rigeur for coding books these days, but good to see nonetheless. In summary, if you want to try your hand at some simple iPhone apps, you really will need this book.
Getting ready to start iPhone development project that will need to take a photo and then modify it. Can you give me some good reference sites to get me started.
Thanks in advance
Bob Williams
Well, I found it tricky because I’d not done any image processing before, and hadn’t even done much C programming. However this code on googlecode was helpful to get started:
http://code.google.com/p/simple-iphone-image-processing/
The code didn’t seem to work as-is with colour, but with some hacking around you should be able to get it working.
Basically you just have to remember that each pixel in a colour image has three 8-bit colour channels and an alpha channel, each with values between 0 and 255. So processing an image consists of looping through bytes 1-4, 5-8, etc (ie pixel by pixel), modifying the values for each byte (channel) to get the colour you want for the overall pixel.
The principle is simple, but getting it right in practice is a bit fiddly.
Good luck!