By Werner Ruotsalainen on Sat, 07/02/2011
Having dug deep into the configuration files and the video “hacking” of the iPhone 3G S (see my yesterday's post HERE [beware, it's quite technical and mostly meant for advanced users / programmers]; I'll also very soon post a full all-in-one 3G S article for beginners), I've found the „1080p” settings I've used there applicable to the iPhone 4 too – in addition to the default (here: true HD with full frame rate, near field-of-view and bad low-light performance) and the full sensor (high-resolution video with great low-light performance and, on the iPhone 4, greatly widened field-of-view but severely reduced frame rate).
The new setting is available right in Simple view, on the main page:
(a red oval shows the new setting)
The new iPhone 4 video enhancer is available in Cydia, in the usual repository http://winmobiletech.com/cy. As usual, I've made the full(!) sources available; they're HERE (old, 1.0 sources HERE). Please read at least the section “My setter program” HERE for a quick introduction to how the utility needs to be operated.
When to use it?
Unfortunately, as has already been hinted, nothing is all roses. Both enhanced (the new “1080p” and the old “full sensor”) modes have compromises and you'll need to consider them all before taking a shot of a given scene. But let's start with the basics.
What does this new setting bring to the table, compared to the, in some respects (on the iPhone 4, frame rate-wise), quite handicapped full sensor mode? First and foremost, exactly the same as on the 3G S (apart from getting rid of the clicking and other bugs there): full frame rate. In addition, on the iPhone4, it will provide the same wide(r) angle view (appr. 32 mm euqiv.) as the 14-15 fps full sensor mode. The latter is the main Raison d'être of my enhancer tool at all, as I find the default, non-enhanced/hacked video mode having far too near a field-of-view (appr. 40 mm euqiv.) to be generally usable for my purposes.
The problems and disadvantages, compared to the true sensor mode, are the same as on the 3GS: reduced true resolution and light sensibility. However, if you need a camera mode that requires both
- a (comparatively) wide angle lens where the default appr. 40 mm. of the iPhone4 is just too narrow and
- fast frame rate
as opposed to low-light sensitivity or pure resolution, this third, just-introduced mode is what you're looking for.
As with the 3G S hack, I've added the new mode named as “1080p”. Note that, as with the 3G S hack, this doesn't state the system is actually recording in 1080p resolution (more on the usable resolutions later); it's just referring to the two “Sensor” parameters (Width and Height), which, in this case, are effectively 1920 and 1080, respectively. Note that you can use higher values as well, as long as you remain under the full size of the sensor. That is, you can go up to 2047*1535 when providing these values – but no further. (2048*1536 is the native resolution of the sensor; if you use these as the capture parameters, you'll be using the slower, albeit higher-quality “Full sensor” mode implemented right from the start).
Note that I'll provide real resolution comparisons between the full sensor mode and the newly introduced 1080p mode in the next section, when I also discuss the question of further raising the recording resolution on the phone.
So far, I've been using XGA (1024*768) as a recording resolution. Now that I had some more time, I played a bit with further increasing this in order to record better videos. I've found out 1102*826 to be the maximum the system can use in the enhanced mode. (Actually, it's one more: 1103*827; but, then, a one-pixel-wide green stripe will be displayed on both the right and bottom edge of the video. You can see this in effect in the videos & screenshots below, which were all taken using 1103*827. My tool uses 1102*826 as the pre-defined resolution.)
Is there any point in using this resolution, you may ask. With the new, 1080p mode, it isn't, as the effective resolution there is considerably worse than that of the full sensor mode. With the latter mode, however, the new mode (which means 78*58 pixels more, compared to the old XGA resolution) provides a bit better resolution. In real life, the difference is pretty minimal, but it's still there. Compare the following four enlarged framegrabs (original MOV videos you can take a closer look at, in the same order, HERE, HERE, HERE and HERE):
(Click the thumbnails for the original framegrabs with the full scene!)
As you can see, there is a slight difference in true resolution between the first (original XGA recording resolution used in v1.0 of my utility) and the second (further increased 1103*827 recording resolution introduced now) shot: at least some of the letters / numbers on the second are somewhat easier to recognize. The second pair of the framegrabs, while, physically, they both use the largest, 1103*827 recording resolution, have way worse resolution / readability (and, for that matter, considerably worse light sensitivity and, consequently, more video noise also apparent on, for example, the outer half of the door).
All in all, you'll always have the choice of two evils: either you will have excellent resolution and low-light performance (but low framerate), or the opposite, but not both at the same time. But, at least, they both fix the biggest problem with the iPhone4 video camera: the narrow field-of-view...