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Topic: Does Photosynth 2 still avoid duplicate photo uploads?

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NateLawrence (7 months ago)
I've been wondering whether Photosynth 2 attempts to hash photos before upload to see whether they've been uploaded before and avoid wasting time uploading a duplicate as the original synther did.

Is this not something that can easily or quickly be done with a browser?

What priority do you give this feature?
NateLawrence (7 months ago)
I uploaded several synths on Christmas Eve/early Christmas morning and one of them stalled at 97% complete with no 'Retry' to click to resume.

I have restarted the upload in a new tab and left the original open, however the new one began uploading all photos from scratch, ignoring any of the photos which did successfully upload last night, so it appears that there is no hashing prior to upload and therefore no more avoiding duplicate uploads.

This means that with the new Photosynth, if you ever make a synth over again or use the photos with others to create a different synth, you will need to re-upload all photos, which is inferior to Photosynth 1.
PhotosynthTeam (7 months ago)
You're correct. It's not as efficient as the original Photosynth in that regard.
NateLawrence (7 months ago)
I realize that it should not often be a case that if a photo set was shot for one of the synth types that it would be likely to succeed as a different type, but there are cases such as kite aerial photography synths which the author may want to try as both a walk and a wall. It may not technically follow either type very strictly.

It seems a shame to require a full redundant upload just to retry a synth as a different synth structure.
If someone has uploaded a significantly sized photo set and met with less than successful results, might I suggest that rather than only the option to delete it that the user might be given the option to retry as a different synth type?

I do realize that you would have to place some sort of limit on the recalculations so that someone could not bring your compute to its knees by constantly retrying a large set of photos that isn't going to synth, but it's fairly disheartening to have to begin from scratch again from our end.
NateLawrence (6 months ago)
As a design point, I would say that not having this check at upload makes using online photo stores as an upload source even more desirable.

If it is too technically challenging or time consuming to calculate a hash for each input image in JavaScript prior to upload to check whether that photo is been uploaded in the past, then give the user the freedom to upload once to SkyDrive etc. on our own and then have Photosynth load from there multiple times so that the user does not have to spend their bandwidth on retries.

::

Having a 'photo source' link to Flickr, Picasa Web, etc. that the synth author can make listed or unlisted (but which defaults to public for synths with Creative Commons or Public Domain licenses so as to make them meaningful) could also potentially give your author users a way to provide their viewers easy download access to the source photos without burdening your storage with the bandwidth of users downloading a full resolution 200 photo synth.
NateLawrence (5 months ago)
As I've been going back and retrying some of my content from Photosynth 1 synths, I've experienced more of this where I've selected a subset of 200 from a larger walk, etc. and uploaded a full 200 photo new synth only for it to fracture in the middle or at two points (making half to two thirds of the upload useless and therefore requiring a full re-upload of that range of photos to test those ranges as their own synth).

It's been making me wish that all photos that I've uploaded to at least Photosynth 2 could be browsed as a photo library for starting new Photosynth 2 synths.

Ideally, in future, I could select subsets of Photosynth 1 photos using a combination of: 
1) an overhead view of the camera frusta (as seen in Henri's WebGL photosynth 1 viewer or Greg's iSynth app) which makes selecting spins, walks, walls, and pans trivial and 
2) a chronological listing of images (useful for selecting ranges through an area with many overlapping camera positions).
I definitely support Nate's last comment requesting for migration tools. Migrating is a pain in the neck as I have experienced here http://photosynth.net/discussion.aspx?cat=00581351-82d8-438d-a37b-7eadb3fb4991&dis=9ebf8cea-8684-4508-86a8-a5b9c5b632cf
where I have also made a remark about migration tools.
NateLawrence (5 months ago)
Yep. In Joscelin's discussion I linked to a small gallery of overhead views of camera positions in a few synths in Henri's WebGL synth viewer in that topic which illustrates my thoughts about overhead view of camera positions as a way of selecting photos for PS2 synths. Here's the link: http://bit.ly/ps1tops2cams

I think that most users (myself included) probably have a fair number of original synths which do not conform cleanly to the new synth types, however since the new synth motions were all basically described in the original Photosynth Photography Guide there are a number of older synths which still convert fairly cleanly in large part.

There are certainly exceptions even in cases where the PS2 motions were being used and the photography is more structured where one has things such as:
:: a spin of walls 
:: a wall of pans 
:: a wall of spins 
:: a spin of spins
:: a walk of pans
:: a walk of spins
etc. to complete the geometry and lock the scene together.
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