I’m seeing a trend on blogs and social media sites for people to post their images flipped like in a mirror. Is my sampling horribly skewed or is this an actual trend? And what’s the reason?
And no, I’m not talking about shooting yourself in the mirror. These are webcam-images and similar and for some bloggers appear to be universally mirrored.
My sister’s mac, when using the webcam, shoots a mirror image. I assume that’s the reason for all the backwards pictures.
Why it does that, I’m not sure.
How can you tell? Is there backwards printing in the picture?
I do know people reverse videos on YouTube to try to avoid the automatic copyright tools, but it doesn’t sound like what you are talking about is related.
I do admit that I prefer my webcam picture of myself to be reversed. It doesn’t matter which way it is on the other end, but, on my end, it’s horribly disconcerting. If I can’t reverse it, I shut off the ability to see myself and just hope I stay in frame.
Those are the most obvious, yes. There are also other things that are left-right asymmetric, like clothing logos, or microwave ovens. One can’t tell for all pictures, but you might be surprised of often it’s possible to figure out if a picture is mirrored or not.
The Mac explanation seems reasonable, although it’s weird Apple has mirroring as standard.
I assume the intent of the mirroring is so you see an image that looks “right” to you – i.e., what you see when you look in the mirror. In the Photo Booth application on Macs, there is a setting that automatically flips photos, but I imagine most people either don’t bother or don’t flip the photos intentionally, because they look weird to them flipped.
That’s what I figured for my sister. When she uses photobooth and the like it’s easier to work with if it’s like looking in a mirror. I’ve always found it odd that it doesn’t flip everything back after it takes the picture. I first noticed this a while ago when she shot a video of my daughter and I noticed that the room was backwards…after that when I noticed that writing on clothing was reversed I figured it was for the same reason.
[sort of big nitpick]
“Flip” is rotation around x-y axis
“Flop”–mirroring–is what is being discussed here
[/sort of big nitpick]
You can either rotate an image, or flip (mirror) an image about its horizontal or vertical axis. I can see someone using flip or flop interchangeably without any confusion. Shoot, I even fail to see any difference between your two definitions.
No Cite?
I think what he’s saying is that a flip is upside down and a flop is backwards.
A flipped image or reversed image, the more formal term, is a static or moving image that is generated by a mirror-reversal of an original across a horizontal axis
A flopped image is a static or moving image that is generated by a mirror-reversal of an original across a vertical axis
Jargon of a particular industry.
What the heck is an ‘x-y axis’?
Ok, we’re going into semantics (in its real sense). Yes, a mirroring is a “flip”-- as described by a human with stuff in his hand–into a position where the image is reversed in depth (flipped into depth, ie into the z-plane). But this mental concept, like rotation, holds on to the physical experience of working with physical material, which makes sense considering how recently the changeover to digital has been.
In the non-digital image practice if you take a negative and physically turn it over, usually by accident, the image is flopped.
This can be dismissed as “industry jargon,” but normally it takes a while for meanings to change, and initial meanings left to vanish but live on in etymology. That time is, I believe, not arrived full-fledged. But I leave it to common practice, and will regret the loss of specificity of meaning in describing imagery. ::sigh::
Note that OP needed to add the words “like a mirror” to “flipped,” whereas the correct word would obviate the meaning.
Hijack, but I think interesting in this context:
Why, in a real mirror, if light paths are consistent in all directions, do we see ourselves reversed but always standing up? Feynman addressed this.
I like the last link … "x to the left and y to the sky"
I wondered about that too, but if you figure he meant to say z-axis it makes sense.
That’s what I thought too, but when you think about it, a rotation about the Z axis doesn’t work.
In this context Z axis would usually be considered as “coming out of the page”, and rotating by this axis would be akin to a barrel roll.
If you roll a photograph by half a rotation, what was in the top-left corner is now in the bottom right. This is not the same thing as flipping an image where, by comparison, what was in the top left would now be in the bottom left.
Put a thumbtack in the center of a picture and spin it [the picture]. The thumbtack is the z-axis. The picture never breaks the xy plane. Rotating something on the xy plane about the x or y axis involves the third dimension (other then a few exceptions).
Yes, but I don’t think you’ve understand my point.
Put a thumbtack in the center of a picture and spin it. Whatever rotation you perform will not be equivalent to flipping the picture.
So my best bet for what Leo Bloom meant by “x-y axis” is, simply, “x axis”.
I work in CG/3D, so x,y,z axis becomes very ingrained. The typical orientation is the x axis runs horizontal, y runs up and down, and z would be your depth – to and fro.
If you want to mirror an image horizontally, you would rotate it on its y axis.
If you want to mirror an image upside-down, you would rotate it on its x axis.
If you wanted to turn or rotate an image (mirrored or not) you’d rotate it on its z axis.
Whether or not esoteric lingo exists about ‘flipping = mirroring’ and ‘flopping = upside down’, it’s certainly not standard. If I were to tell a designer to flop that image, and it wasn’t returned mirrored upside down, but mirrored horizontally, I could only blame myself for not being clear.