Johan Benesch's dashboard

Johan Benesch marked one of mrb's replies in Microsoft Live Labs as useful. mrb replied to the idea "Manual hinting".

A comment on the idea "Manual hinting" in Microsoft Live Labs:

and if you do manual hinting of one pic each in two orphan synths the rest should by default be synthed automatically, since already are coupled via their own synth matches. – Johan Benesch, on October 09, 2008 09:33

A comment on the question "Timeframe for update allowing 'Add Photos/Edit' options?" in Microsoft Live Labs:

I agree with Nathanael Lawrence. there is more on this i this thread: http://getsatisfaction.com/livelabs/t...

just noting that when going back for some complementary shoots things might have changed, like cars parked in front of a building or people walking/sitting near a statue etc

I aspire to get a 100% synth one day :-) – Johan Benesch, on October 01, 2008 17:53

Johan Benesch started following the question "Timeframe for update allowing 'Add Photos/Edit' options?" in Microsoft Live Labs.

Johan Benesch replied on September 29, 2008 13:25 to the idea "Merge point groups to increase 'synthiness'" in Microsoft Live Labs:

i recently also tried to synth a building.
when i redid the synth with many more pics to better cover the corners
the synthiness dropped ...

since you have pretty good idea which "orphan synths" that have overlap it would be great to be able to give that input to the software.
could be as simple as drag-and-drop one pic in one "orphan synth" to a good overlap with a pic in another "orphan synth".

Johan Benesch started following the idea "Merge point groups to increase 'synthiness'" in Microsoft Live Labs.

Johan Benesch started following the question "Manual Synching And Autosynching On The Computer" in Microsoft Live Labs.

A comment on the question "Manual Synching And Autosynching On The Computer" in Microsoft Live Labs:

theory is nice but in practise this does not work for photosynth.

so some kind of manual input on how to make the synths could bring up the synthiness to 100%, probably fairly often ... – Johan Benesch, on September 29, 2008 13:20

Johan Benesch started following the question "Manual hints, also useful for picture in picture" in Microsoft Live Labs.

Johan Benesch replied on September 29, 2008 13:18 to the question "Manual hints, also useful for picture in picture" in Microsoft Live Labs:

seems like similar problem as if people are standing/walking inbetween camera and object. and yes I agree that some level of manual would very much improve the outcome of synths.

A comment on the idea "Manual hinting" in Microsoft Live Labs:

i deleted the above synth and replaced with this one
http://photosynth.net/view.aspx?cid=f...
285 pics 22% synth, 31 "orhapan synths" 25 orphan images
i added ca 60 more pictures of the 4 corners of this building,
it just got worse ... – Johan Benesch, on September 29, 2008 13:15

Johan Benesch replied on September 10, 2008 20:19 to the idea "Navigate the synth through a display of the synthed links betweeen images" in Microsoft Live Labs:

hmmm, you mean for cases when there are pictorial overlaps although the synther did not find them or for objects close in "space" for a given viewpoint.

in the first case one solution is manual hinting
http://getsatisfaction.com/livelabs/t...

the latter could perhaps be expanded into linking to synths made by others on the same spot (of the same objects), if they have been mapped.

perhaps this could be overcome the synther could use coordinates from the exif, of course the user needs to add them (e.g. with the help of a GPS data logger)

Johan Benesch replied on September 10, 2008 18:59 to the idea "Please tell us what percentage of the photo is "synthy" in advance" in Microsoft Live Labs:

sounds like answering a question before you have all the facts you need have in order to be able to answer it ...

Johan Benesch replied on September 10, 2008 18:55 to the idea "Debug tool: point cloud heat map" in Microsoft Live Labs:

sounds like a good idea
should be coupled with a way to upload more images to a synth

but then the orphaned images and "orphan synths" are of much larger concern

Johan Benesch started following the idea "Debug tool: point cloud heat map" in Microsoft Live Labs.

Johan Benesch replied on September 10, 2008 18:51 to the idea "Manual hinting" in Microsoft Live Labs:

sounds like a great idea!

the manual part could be make easier than finding specific points in an orhpanhed image:
- drag one photo from one "orphan synth" to one specific image in another "orphan synth".
- then the "synther" would take it from there.

see here for example
http://photosynth.net/view.aspx?cid=6...

217 images
16 "orphan synths" and 17 "orphan images"

Johan Benesch started following the idea "Manual hinting" in Microsoft Live Labs.

Johan Benesch started following the idea "Navigate the synth through a display of the synthed links betweeen images" in Microsoft Live Labs.

David Gedye's reply to "Don’t crop images." was just promoted to the most useful! Johan Benesch and 3 other people think it's one of the best replies.

Ok -- here's the whole story. Photosynth assumes that the center of your photograph was exactly where your lens was pointing when you took the photo. If, for example, you crop away the left half of your photo, photosynth will assume that the middle of the remaining piece was where the lens was pointing -- which is wrong.

Why does this matter? It matters because the main computer vision magic of photosynth is an algorithm called "bundle adjustment" which works out exactly where each of the photos was taken from and exactly which way the camera was pointing when the photos were taken. Photosynth gets confused if you crop because it gets the wrong idea about what subject was directly in line with central axis of the lens.

Well does that mean that you can crop as long as you do it symmetrically? The answer is a guarded yes. It's not a complete yes because the other piece of information that Photosynth uses is the focal length as reported in the photo's EXIF tag. If you crop then you are simulating a lens with a different focal length, and this too will confuse Photosynth. However, Photosynth is fairly resilient to focal length errors, so it usually works.

More than you wanted to know?
David.

A comment on the question "not all images are used to make a photosynth" in Microsoft Live Labs:

see the post by Stuartr above.

in some cases some manual input in making the synth could help a bit. – Johan Benesch, on September 10, 2008 09:29