Processing panoramic videos with GoPano micro can be a little confusing. You may find yourself browsing the iPhone 360 videos on http://www.gopano.com/ asking, “Why do videos that look sharp straight from the camera look fuzzy with the optic attached?” To answer that, let’s take a look at what’s going on behind the scenes.
Below is a frame of panoramic video taken with the GoPano micro attached to an iPhone 4. Aside from the annotations, it is completely unaltered.
There are more pixels looking below the horizon (outside of the doughnut) than above the horizon (inside of the doughnut). This results in the top of the image looking fuzzier than the bottom because there’s less data to work with. (Note: you can record things upside-down if you want more detail up above).
Panoramic Video: Where Have My Pixels Gone?
iPhone 4 captures a normal 720p movie, which is 1280 pixels wide by 720 pixels tall. The first thing viewers are likely to notice is that the mirror image covers a fairly small portion of the image sensor. While a 720p movie has 921,600 pixels per frame, the iPhone 360 video only uses about 350,000 of those pixels, which are then spread across the entire 360 degree view, floor to ceiling.
The GoPano App takes the raw camera frame and “unwarps” it, stretching out the image that started as a circle and forming it into a cylinder that wraps around. It’s comparable to the reverse process of making paper globes, like you may recall doing as a young student in grade school.
When the panoramic video image is unwarped, it looks like this:
And that, friends, is the whole 360 degree view. The left side wraps around to the right creating an image that is smaller than the original, at about 390,000 pixels.
Alternatively, let’s look at a view in a single direction, like you’d see when playing back the panoramic video interactively:
iPhone 360 Video: Camera Resolution Improvements
Now that you’ve been schooled in pixels… We can share the Good News:
…as camera resolution improves, so does the quality of the 360 degree video you can achieve.
Already, iPhone 360 video has gotten a little quality boost from the release of iPhone 4S. While we wait for these camera improvements to continue, our GoPano micro team is continuing to advance our 360 degree video technology. We are working on new software techniques to improve the results from optics and cameras already in the field, and our enthusiastic team of experts is inventing new ways to “bend” the laws of physics.
360 Degree Video: Another Perspective
Looking for another perspective on the panoramic video images discussed above? Check out the following video examples. The first is a standard GoPano 360 video:
Now, watch the same video laid flat:
Have some input on panoramic video, pixels, or unwarping? Feel free to chime in on the ‘behind the scenes’ discussion by leaving us a comment here.