First look: Taking HDR photos with Apple's iOS 4.1
When iOS 4.1 ships next week, iPhone and iPod touch users will have a new feature that allows for better photos in bright lighting: High Dynamic Range. AppleInsider offers a first look at the new technology built right in to the iOS Camera application.
HDR photos allow for superior pictures in daylight or other bright settings. Particularly when a shadow is cast on the subject or a part of the photo, it allows for a more accurate representation that doesn't allow the light or shadow sources to overpower the picture and result in a murky or discolored photo.
The new feature aims to prevent photos that are "blown out" with too much light. It accomplishes this by taking three photos in rapid succession: one with normal exposure, one underexposed, and another overexposed.
By combining these three photos, iOS 4.1 uses what Apple Chief Executive Steve Jobs referred to in his keynote Wednesday as "pretty sophisticated algorithms" to produce an HDR photo.
"It's really remarkable in some photos," Jobs said. He then showed examples of how HDR allows a picture to capture colors in the sky and details in the foreground that otherwise would have been blown out by the light of the sun.
Tested on an iPhone 4, the HDR function is in fact a great option for users built right in to the native Camera application. If a picture is appropriately focused before it is snapped, the resulting photo is often superior to the regular picture.
On the left, without HDR. On the right, with HDR enabled.
Based on the conditions of the shot, HDR option won't always provide a better photo, but through the Settings application, users can elect to save both the "normal" photo and the HDR photo, and they can go back and decide which shot looks better. Users are asked if they want to save both HDR and regular photos the first time they boot the application after installing iOS 4.1.
In general, focusing the iPhone 4 camera lens on a darker area results in a better picture with HDR enabled. Focusing on a brighter area, however, can sometimes have the opposite effect, and create in a photo even more blown out -- particularly if the photo is a bright subject being snapped from the shade.
On the right, HDR fixes the overpowering sunlight seen in the normal photo.
Photo taken from shade, HDR photo on the right results in a more washed out sky, though areas in shadow have more detail.
On the left, without HDR. On the right, with HDR enabled.
The HDR feature does not work with pictures snapped with the forward facing camera on the iPhone 4. Selecting HDR also automatically turns off the flash function for the rear camera. Changing the flash back to auto or on will likewise disable HDR.
When taking a photo, the Camera app presents an on-screen toggle to switch HDR on or off, wedged between to the flash and camera swap controls.
When browsing photos in Camera Roll, HDR snaps are identified appropriately in the upper left corner.
HDR options in the Settings app.
Other changes in 4.1
iOS 4.1 also fixes bugs that have existed in iOS 4, including a problematic proximity sensor issue that would cause the touchscreen to sometimes become active when a user was on a call. It also addresses problems with Bluetooth connectivity, and slow performance for users running the iPhone 3G.
The latest version of iOS also brings the ability to upload HD video over Wi-Fi, including uploads to YouTube. It also allows for TV show rentals, which were unveiled alongside the new Apple TV introduced Wednesday. And iOS 4.1 also ships with Game Center, Apple's social media service for gamers with friends lists and achievements.
iOS 4.1 will become available for recent generation iPhones and iPod touches next Wednesday Sept 8. It will be followed by iOS 4.2, which will bring wireless printing and AirPlay to the iPhone, iPod touch and iPad in November.
For more on iOS 4.1, see AppleInsider's previous in-depth look: Inside Apple's iOS 4.1 update: proximity sensor fix, Game Center, more.
HDR photos allow for superior pictures in daylight or other bright settings. Particularly when a shadow is cast on the subject or a part of the photo, it allows for a more accurate representation that doesn't allow the light or shadow sources to overpower the picture and result in a murky or discolored photo.
The new feature aims to prevent photos that are "blown out" with too much light. It accomplishes this by taking three photos in rapid succession: one with normal exposure, one underexposed, and another overexposed.
By combining these three photos, iOS 4.1 uses what Apple Chief Executive Steve Jobs referred to in his keynote Wednesday as "pretty sophisticated algorithms" to produce an HDR photo.
"It's really remarkable in some photos," Jobs said. He then showed examples of how HDR allows a picture to capture colors in the sky and details in the foreground that otherwise would have been blown out by the light of the sun.
Tested on an iPhone 4, the HDR function is in fact a great option for users built right in to the native Camera application. If a picture is appropriately focused before it is snapped, the resulting photo is often superior to the regular picture.
On the left, without HDR. On the right, with HDR enabled.
Based on the conditions of the shot, HDR option won't always provide a better photo, but through the Settings application, users can elect to save both the "normal" photo and the HDR photo, and they can go back and decide which shot looks better. Users are asked if they want to save both HDR and regular photos the first time they boot the application after installing iOS 4.1.
In general, focusing the iPhone 4 camera lens on a darker area results in a better picture with HDR enabled. Focusing on a brighter area, however, can sometimes have the opposite effect, and create in a photo even more blown out -- particularly if the photo is a bright subject being snapped from the shade.
On the right, HDR fixes the overpowering sunlight seen in the normal photo.
Photo taken from shade, HDR photo on the right results in a more washed out sky, though areas in shadow have more detail.
On the left, without HDR. On the right, with HDR enabled.
The HDR feature does not work with pictures snapped with the forward facing camera on the iPhone 4. Selecting HDR also automatically turns off the flash function for the rear camera. Changing the flash back to auto or on will likewise disable HDR.
When taking a photo, the Camera app presents an on-screen toggle to switch HDR on or off, wedged between to the flash and camera swap controls.
When browsing photos in Camera Roll, HDR snaps are identified appropriately in the upper left corner.
HDR options in the Settings app.
Other changes in 4.1
iOS 4.1 also fixes bugs that have existed in iOS 4, including a problematic proximity sensor issue that would cause the touchscreen to sometimes become active when a user was on a call. It also addresses problems with Bluetooth connectivity, and slow performance for users running the iPhone 3G.
The latest version of iOS also brings the ability to upload HD video over Wi-Fi, including uploads to YouTube. It also allows for TV show rentals, which were unveiled alongside the new Apple TV introduced Wednesday. And iOS 4.1 also ships with Game Center, Apple's social media service for gamers with friends lists and achievements.
iOS 4.1 will become available for recent generation iPhones and iPod touches next Wednesday Sept 8. It will be followed by iOS 4.2, which will bring wireless printing and AirPlay to the iPhone, iPod touch and iPad in November.
For more on iOS 4.1, see AppleInsider's previous in-depth look: Inside Apple's iOS 4.1 update: proximity sensor fix, Game Center, more.
Comments
I ain't losing my jailbreak over that.
Nor am I. But it does leave me looking forward to a jailbroken 4.1.
For instance, I've taken photos of people at night on the beach with flash, and the background details are lost in the darkness. That's when HDR would come in handy, blending a non-flashed background with a flashed-subject.
-kpluck
This is a pretty cool feature. I've done HDR by hand, and it can be a tedious process. Too bad it doesn't work with the flash, because sometimes those are the photos that need it the most.
For instance, I've taken photos of people at night on the beach with flash, and the background details are lost in the darkness. That's when HDR would come in handy, blending a non-flashed background with a flashed-subject.
Exposure blending is not the same as HDR and tone mapping. Both can be useful.
It will be interesting to see how Apple's HDR implementation stacks up to some of the 3rd party apps. I have been using ProHDR and have been very happy with it.
I can address that, as I am, was, a ProHDR app user. Overall, I would say that third party solutions have to try a lot harder, now. With PHDR, you have to wait for the program to take three pictures and try to keep things steady in the process. With the built-in camera, you just snap your pic, and it takes it instantly.
In truth, three pictures are taken in the background, as I understand it. But you never notice anything other than the one picture that is quickly taken. You do have to wait for a few seconds for the pictures to process. But again, you do not have to keep holding steady while that happens. There is just a short delay between the time you take one pic before going to the next.
I think Apple also made some white balance improvements, as everything about the HDR picture looks much truer to what you saw when you took the picture.
Exposure blending is not the same as HDR and tone mapping. Both can be useful.
I've been reading up on this for the last few days in anticipation. I have yet to find a straight-forward explanation of the differences between HDR, exposure blending and tone mapping. It sounds like the latter two are essentially methods within the HDR process, but that might not be entirely accurate. From what I'm hearing, the iPhone version of HDR is essentially exposure blending. I wonder how much these distinctions will matter to the audience Apple is targeting for iPhone HDR.
I ain't losing my jailbreak over that.
Nor am I. But it does leave me looking forward to a jailbroken 4.1.
You don't have to you can steal the proHDR App from the pirate repositories that jailbreaking enables.
You can even use the lame old excuse of "I'm only testing it before I buy it".
I wonder how much these distinctions will matter to the audience Apple is targeting for iPhone HDR.
It won't matter at all. They get a better shot. It's -easy-, no options etc.
Some "Pro's" will show they aren't pro by complaining it's only this or that.
It might increase sales of HDR apps as people become interested in the idea from being -exposed- to it and then wanting more options.
You don't have to you can steal the proHDR App from the pirate repositories that jailbreaking enables.
You can even use the lame old excuse of "I'm only testing it before I buy it".
No need to be a proactive dick.
What kind of ass assumes all jailbroken device users pirate apps?
I've spent over $400 on the App Store and have zero pirated apps on my phone. I haven't even installed the hack that would enable me to download them in the first place. I jailbreak because I don't love any games quite like I love some of those old Super Nintendo/NES/GBA games I used to play. Jailbreaking gives me access to nearly all of them and much more enjoyment out of my device. And before you decide to be a dick about that, too, I actually own physical copies of the games I play. I probably should have sold them.
And before you decide to be a dick about that, too, I actually own physical copies of the games I play. I probably should have sold them.
That you own physical copies is neither here nor there. It might justify what you're doing in your mind but it doesn't change the equation at all.
I also jailbreak as it happens and have zero pirated apps. Solely jailbroken for SBSettings, which I can live without but 1 action access to a significant device settings such as brightness and turning wi-fi off (for Runkeeper) is so convenient. I am surprised Apple haven't implemented such a scheme themselves.
I rarely take my standalone camera along anymore and this addition to iOS should make things even better. But, like you I will wait until a jailbreak comes along.
Exposure blending is not the same as HDR and tone mapping. Both can be useful.
You are incorrect. Actually HDR, or high dynamic range images, are achieved by blending several (I use 3) exposures of low dynamic range, LDR i.e. 'normal images'. The three are taken at different exposures to capture the luminance of the three exposures, usually one stop apart, one either side of the best compromise and best if they are RAW for obvious reasons. Tonal mapping is a procedure done with the data collected and merged within the software used for the afore mentioned process - mainly contrast compression to allow viewing of the effect in a lower dynamic range. I have been playing with this for a while using high end software and RAW images. It can create some mind boggling results. Apple I suspect have a simplified system here but never the less a useful feature that adds some fun to a simple iPhone.
Having already updated my phone to 4.1 via unofficial channels, I can tell you that the feature is outstanding. At this point, the point and shoot industry is having a hard time justifying its existence.
So far I've had the opposite reaction. Apple's HDR algorithm seems to really wash out color and make things seem flat and lifeless in my tests. There are maybe 1 in 10 shots that it improves and 5 in 10 it makes worse. I fear that everyone is going to turn on HDR and leave it on and just get slower performance (HDR pics take several seconds to take on an iPhone4 versus instant for normal pics) and worse results.
The camera is _not_ HDR. The resultant photo is _not_ HDR. The process in between could just possibly be called HDR, but we'd need to see a sensor of at least 9 or 10 bits to truly claim an HDR process: 1-8 for low exposure, 2-9 for medium, 3-10 for high, or some such. If not, you're just combining three 8-bit images, one of which is underexposed and one overexposed/bleached, in order to reduce dark and bleached areas.
Having already updated my phone to 4.1 via unofficial channels, I can tell you that the feature is outstanding. At this point, the point and shoot industry is having a hard time justifying its existence.
I suspect that in about two to three years we ought to have sensors using Quantum Dots which should dramatically improve the sensitivity of cell phone cameras. Of course that is only one element needed to improve the utility of cell phone cameras, we still need a way to stuff better optics into these small devices. There is nothing digital that can compare to a good zoom lens for example.
In any event cell cameras are closer than they every have been to being good enough.
Dave
You are incorrect. Actually HDR, or high dynamic range images, are achieved by blending several (I use 3) exposures of low dynamic range, LDR i.e. 'normal images'. The three are taken at different exposures to capture the luminance of the three exposures, usually one stop apart, one either side of the best compromise and best if they are RAW for obvious reasons. Tonal mapping is a procedure done with the data collected and merged within the software used for the afore mentioned process. I have been playing with this for a while using high end software and RAW images. It can create some mind boggling results. Apple I suspect have a simplified system here but never the less a useful feature that adds some fun to a simple iPhone.
Not at all. An HDR image is 'higher dynamic range', really, than the commonly accepted 8-bits (256 steps) of current image technology. You need an image of 9 bits or more to be an HDR image as the term is currently accepted.
Apple _is_ exposure blending, and it's a great effect, but it's not HDR.
This is a pretty cool feature. I've done HDR by hand, and it can be a tedious process. Too bad it doesn't work with the flash, because sometimes those are the photos that need it the most.
For instance, I've taken photos of people at night on the beach with flash, and the background details are lost in the darkness. That's when HDR would come in handy, blending a non-flashed background with a flashed-subject.
Google Slow Sync Flash. That is the technique that already exists to do what you request and it is better if you are handholding or shooting human subjects since there is only one exposre taken.
Of course the iPhone has no manual controls, but perhaps an enterprising App developer could implement this technique in software...