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![]() | The contents of the Optical flow sensor page were merged into Optical flow. For the contribution history and old versions of the redirected page, please see its history; for the discussion at that location, see its talk page. |
From the mathematics, it seems clear this is based on a scene where the illumination has a gradient. In controlled environments with Köhler illumination, etc the technique of optical flow is not applicable. This aspect should be spelled out in the introductory portions as it is easy to understand and fundamental to the mathematical explanation. Many 'machine vision' topics are usually focused on macroscopic machine navigation. Vision application domains are actually quite huge and I think it would serve everyone well to indicate some of the assumptions of any robotics mechanism. Some can be reused for microscopy vision, geography recognition, surveillance, etc. 206.223.175.102 ( talk) 14:40, 22 December 2020 (UTC)
You know it is interesting, I always considered Optical Flow to basically be a repercussion of time-reverse physics. (Reverse the flow of time, and position stays the same, etc. but velocity flips directions..) A la /info/en/?search=T-symmetry
In any case, now that the topic is pretty mature- and lots of products ostensibly written, does it make sense to do something like this, except for Optical Flow?: /info/en/?search=Comparison_of_image_viewers (woulda linked my URLS, but I gotta jam). Cheers1
Know Einstein ( talk) 23:03, 2 August 2022 (UTC)
As a current researcher in the area I am a bit concerned by some confusion some of my students might have visiting this page so I thought to make a list of things that might be beneficial to investigate or change in the event myself or someone else has time.
If anybody finds additional notes or concerns please add them for consideration here. For the best suite of current and archived Optical Flow papers I generally find the IEEE does rather well. —Preceding unsigned comment added by 67.247.88.34 ( talk) 08:50, 26 April 2011 (UTC)
Good list. Another mild concern is that the introduction and estimation are confusingly given about Optical Flow estimations on 2D images which are observations of the 3D world. Although this is a clear and common use case, this has two problems: (i) Optical Flow is a method in its own right for 2D images, as it is for instance a very well-known tool in medical imaging and (ii) the main text subsequently motivates that 3D/nD Optical Flow exists as well, which is clearly not an observation/projection from a higher dimensional world. I think the text should be structured in a way where the method, regardless of dimension and setting comes first, and then has a section on Optical Flow on images from real-world observations.
Optical flow can be 2 or 3 dimensional, it can even be n-dimensional. —Preceding unsigned comment added by Dawoodmajoka ( talk • contribs) 16:31, 8 February 2009 (UTC)
The author specifically states that the optical flow is, essentially, a dense motion field. That would make it a noun. However, both this article and the motion estimation article use the term as a verb. Will DIP please make up their collective minds about this and stop confusing the rest of us. Alternatively, please stop using this redundant term all together. Dhatfield ( talk) 07:26, 4 April 2008 (UTC)
Merge with
optic flow? —Preceding
unsigned comment added by
129.215.58.129 (
talk)
06:39, 28 April 2008 (UTC)
Vastly improved from when I last looked here! If you want more pics, talk to me. Dhatfield ( talk) 09:52, 18 June 2008 (UTC)
Arguing that because optical flow is an important component of animal vision that it must also be an important part of computer vision is a logical fallacy. It is equivalent to asserting that, since flapping wings are essential to animal flight, any flying machine must have flapping wings. 19:06, 2 February 2009 (UTC) —Preceding unsigned comment added by 209.211.131.111 ( talk)
The current text describes the case of 3D+t data, but 2D+t is by far the most common type of data used for optical flow techniques and what is discussed in almost all of the literature. I will change to 2D+t shortly unless someone can motivate why 3D+t is better. -- KYN ( talk) 07:28, 20 February 2009 (UTC)
Normally the dot product is between two vectors , or if you use the transpose notation, a matrix product between a row and a column vector written without a dot: . This article's first section uses *both* of these together, which looks a little odd. —Preceding unsigned comment added by 88.110.199.11 ( talk) 21:08, 4 October 2009 (UTC)
I also observed this, and changed the Optical Flow equation at the end of the Estimation section so that it reads instead. — Preceding unsigned comment added by 31.21.15.4 ( talk) 09:17, 13 May 2020 (UTC)
I think the sensors should be discussed in the same article as the methods; no need to separate the material into two short articles just because one involves hardware. Dicklyon ( talk) 17:01, 10 April 2011 (UTC)
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![]() | This article may be too technical for most readers to understand.(September 2010) |
![]() | This article is rated Start-class on Wikipedia's
content assessment scale. It is of interest to the following WikiProjects: | ||||||||||
|
![]() | The contents of the Optical flow sensor page were merged into Optical flow. For the contribution history and old versions of the redirected page, please see its history; for the discussion at that location, see its talk page. |
From the mathematics, it seems clear this is based on a scene where the illumination has a gradient. In controlled environments with Köhler illumination, etc the technique of optical flow is not applicable. This aspect should be spelled out in the introductory portions as it is easy to understand and fundamental to the mathematical explanation. Many 'machine vision' topics are usually focused on macroscopic machine navigation. Vision application domains are actually quite huge and I think it would serve everyone well to indicate some of the assumptions of any robotics mechanism. Some can be reused for microscopy vision, geography recognition, surveillance, etc. 206.223.175.102 ( talk) 14:40, 22 December 2020 (UTC)
You know it is interesting, I always considered Optical Flow to basically be a repercussion of time-reverse physics. (Reverse the flow of time, and position stays the same, etc. but velocity flips directions..) A la /info/en/?search=T-symmetry
In any case, now that the topic is pretty mature- and lots of products ostensibly written, does it make sense to do something like this, except for Optical Flow?: /info/en/?search=Comparison_of_image_viewers (woulda linked my URLS, but I gotta jam). Cheers1
Know Einstein ( talk) 23:03, 2 August 2022 (UTC)
As a current researcher in the area I am a bit concerned by some confusion some of my students might have visiting this page so I thought to make a list of things that might be beneficial to investigate or change in the event myself or someone else has time.
If anybody finds additional notes or concerns please add them for consideration here. For the best suite of current and archived Optical Flow papers I generally find the IEEE does rather well. —Preceding unsigned comment added by 67.247.88.34 ( talk) 08:50, 26 April 2011 (UTC)
Good list. Another mild concern is that the introduction and estimation are confusingly given about Optical Flow estimations on 2D images which are observations of the 3D world. Although this is a clear and common use case, this has two problems: (i) Optical Flow is a method in its own right for 2D images, as it is for instance a very well-known tool in medical imaging and (ii) the main text subsequently motivates that 3D/nD Optical Flow exists as well, which is clearly not an observation/projection from a higher dimensional world. I think the text should be structured in a way where the method, regardless of dimension and setting comes first, and then has a section on Optical Flow on images from real-world observations.
Optical flow can be 2 or 3 dimensional, it can even be n-dimensional. —Preceding unsigned comment added by Dawoodmajoka ( talk • contribs) 16:31, 8 February 2009 (UTC)
The author specifically states that the optical flow is, essentially, a dense motion field. That would make it a noun. However, both this article and the motion estimation article use the term as a verb. Will DIP please make up their collective minds about this and stop confusing the rest of us. Alternatively, please stop using this redundant term all together. Dhatfield ( talk) 07:26, 4 April 2008 (UTC)
Merge with
optic flow? —Preceding
unsigned comment added by
129.215.58.129 (
talk)
06:39, 28 April 2008 (UTC)
Vastly improved from when I last looked here! If you want more pics, talk to me. Dhatfield ( talk) 09:52, 18 June 2008 (UTC)
Arguing that because optical flow is an important component of animal vision that it must also be an important part of computer vision is a logical fallacy. It is equivalent to asserting that, since flapping wings are essential to animal flight, any flying machine must have flapping wings. 19:06, 2 February 2009 (UTC) —Preceding unsigned comment added by 209.211.131.111 ( talk)
The current text describes the case of 3D+t data, but 2D+t is by far the most common type of data used for optical flow techniques and what is discussed in almost all of the literature. I will change to 2D+t shortly unless someone can motivate why 3D+t is better. -- KYN ( talk) 07:28, 20 February 2009 (UTC)
Normally the dot product is between two vectors , or if you use the transpose notation, a matrix product between a row and a column vector written without a dot: . This article's first section uses *both* of these together, which looks a little odd. —Preceding unsigned comment added by 88.110.199.11 ( talk) 21:08, 4 October 2009 (UTC)
I also observed this, and changed the Optical Flow equation at the end of the Estimation section so that it reads instead. — Preceding unsigned comment added by 31.21.15.4 ( talk) 09:17, 13 May 2020 (UTC)
I think the sensors should be discussed in the same article as the methods; no need to separate the material into two short articles just because one involves hardware. Dicklyon ( talk) 17:01, 10 April 2011 (UTC)
Hello fellow Wikipedians,
I have just modified one external link on Optical flow. Please take a moment to review my edit. If you have any questions, or need the bot to ignore the links, or the page altogether, please visit this simple FaQ for additional information. I made the following changes:
When you have finished reviewing my changes, you may follow the instructions on the template below to fix any issues with the URLs.
This message was posted before February 2018.
After February 2018, "External links modified" talk page sections are no longer generated or monitored by InternetArchiveBot. No special action is required regarding these talk page notices, other than
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have permission to delete these "External links modified" talk page sections if they want to de-clutter talk pages, but see the
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(last update: 5 June 2024).
Cheers.— InternetArchiveBot ( Report bug) 17:16, 14 January 2018 (UTC)