canonnews said:
Mt Spokane Photography said:
I'm wondering about that patent we saw for a light field camera last week. It was called out as being a quad pixel patent, but it was actually a light field camera.
That would certainly qualify as something totally new, no one has made a light field camera using dual or quad pixels.
you're reading too much into it. Most of canon's patent applications dealing with phase difference at the sub pixel (dual or quad) refer to it as light field data.
Perhaps, I am not saying this is it, but putting it out for discussion. I can certainly be wrong. There are multiple references in the patent to refocus processing. Of course, that can be done now with a 5D MK IV to a very limited extent, so it could just be a extension of that capability to a quad pixel sensor.
Certainly, the primary virtue of the patent is stated as a supressed file size, but, thats also what is needed to make a light field camera practical.
Usually, they do not just toss stuff in a patent unless it serves a purpose. Refocus techniques are definitely discussed.
* I think this is a broad hint that it could be applied to a light field camera:
"[0003] Ren Ng et al, "Light Field Photography with a
Hand-Held Plenoptic Camera", Stanford Tech Report CTSR
2005 February , 2005 Apr. 20) discloses a refocus technique
in which the in-focus position of the captured image is
changed after shooting by using LF data to combine images
in an imaging plane (virtual imaging plane) different from
that at the time of shooting."
* The patent describes the formation of multiple images with different focus points by combining the
images captured from various combinations of pixels. This is how a light field camera could work.
"0150 The embodiments above described a case in which
the present invention was applied to the generation of an
image file containing parallax images. However, the present
invention can also be applied to the generation of an image
file containing other images having a relationship between a
portion and the whole, as with parallax images and a normal
image, or a relationship in which one image is generated
from another."
* The Patent discusses another aspect of a light field camera.
"14. The electronic device according to claim 11, wherein
the image processing includes at least one of refocus processing,
viewpoint changing processing, defocus map generation
processing, and three-dimensional image generation
processing."
(Claim 11 referenced above should be read with claim 14 above in mind) I read it as the possibility of creating interpolated images as needed to construct a refocused image.
"[0011] According to a further aspect of the present invention,
there is provided a method for controlling an image
processing apparatus, comprising: obtaining data of one or
more of a plurality of first images; obtaining data of a second
image corresponding to a combined image of the plurality of
first images; and generating an image file containing the data
of the second image and data of a portion of the plurality of
first images, wherein the image file is generated such that the
image file does not contain data of, among the plurality of
first images, a first image that can be generated from a first
image and the second image stored in the image file."
The big question is how you could get adequate refocus processing over more than a tiny distance, which is a problem for me with my 5D MK IV.
Although it is not mentioned, a quad pixel processor allows for autofocus in both landscape and portrait orientations, a potential benefit.