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Stitching – A Python package for fast and robust Image Stitching (Panoramas)

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Re: Stitching – A Python package for fast and robust Image Stitching (Panoramas)

#21

Post by bmh »

folli wrote: post #11
bmh wrote: post #3

Earlier quoted context omitted.

Microsoft seems to have discontinued ICE a long time ago. As far as I know, the state of the art in panorama stitching is PTGui. I was working on mobile panorama stitching last year, and one of my datasets had a kitchen wall that was almost purely white, so very little detail for the classic feature algorithms such as SIFT and ORB to cling to. The OpenCV stitching pipeline, which is built on these (and RANSAC), didn'…

So how did you solve the mobile panorama stitching? You ran PTGui on a backend server and uploaded the user images there?

I started from the OpenCV stitching_detailed example, and worked from there. That example runs pretty much out of the box on Android.

Re: Stitching – A Python package for fast and robust Image Stitching (Panoramas)

#22

Post by O5vYtytb »

Wondering if anyone has examples/ideas for how to do this with video? I have two cameras (GoPro) that I use to record athletic games on a 20ft tall tripod, and I want to automatically stitch them together for easier analysis of games. I think I can use a tool like this to find the stitching parameters for the first frame and then apply it to all future frames, assuming the camera doesn't move?

Re: Stitching – A Python package for fast and robust Image Stitching (Panoramas)

#23

Post by StephenSmith »

Mumps wrote: post #19
StephenSmith wrote: post #17

I'd love someone with more CV experience to explain why this fails on my use case? (four image zip) https://drive.google.com/file/d/1gTZWlKmS4ZtEZDK8OjjLeGN_V0F...

(sorry don't have time to run through the OP script and check what you're getting for outputs, but...) - I'm not even entirely sure how these images would stitch together - between 1.jpeg and the rest, there is very little overlap. RANSAC likely won't find matchable points. - you're asking for a pretty severe homography of the scene.

Thanks! That's what I was trying to understand.

Re: Stitching – A Python package for fast and robust Image Stitching (Panoramas)

#24

Post by bmh »

LukasWeber wrote: post #13
bmh wrote: post #3

Earlier quoted context omitted.

Microsoft seems to have discontinued ICE a long time ago. As far as I know, the state of the art in panorama stitching is PTGui. I was working on mobile panorama stitching last year, and one of my datasets had a kitchen wall that was almost purely white, so very little detail for the classic feature algorithms such as SIFT and ORB to cling to. The OpenCV stitching pipeline, which is built on these (and RANSAC), didn'…

A simple GUI would be great to let the user select high quality 3-4 matches (reference points) between the image pairs. Then the rest of the stitching pipeline could stay the same.

I'm convinced after the work I did on panoramas that one shouldn't need to involve user input. Maybe for very strange situations... but generally it shouldn't be necessary. This is especially true if you have access to the IMU on a phone, which helps constrain the potential angles of each of your images.

If your images are just a random bag of jpegs that came in from the cold, then it's harder for sure.

Re: Stitching – A Python package for fast and robust Image Stitching (Panoramas)

#26

Post by ahns »

kwon-young wrote: post #5

In my case, my dad needed a Gui for stitching microscope images and he told me that none of the panorama stitching Guis were working for him. I found out that the out of the box opencv Stitcher [1] class is perfect for that but nobody seems to have made a GUI out of it. So, I've spent two days making an extremely simple proof of concept of a Qt Gui [2]. The majority of the time was spent trying to use GitHub Action t…

For microscopy images, have you tried ashlar?

https://github.com/labsyspharm/ashlar

It may help to have the microscope stage positions available in the OME metadata.

Re: Stitching – A Python package for fast and robust Image Stitching (Panoramas)

#27

Post by zimpenfish »

StephenSmith wrote: post #17

I'd love someone with more CV experience to explain why this fails on my use case? (four image zip) https://drive.google.com/file/d/1gTZWlKmS4ZtEZDK8OjjLeGN_V0F...

Panorama Stitcher (macOS) matched 3 and 4 to give https://imgur.com/a/HnagrrH but image 2 is just too skewed to match, even after rotating in Photoshop, and image 1 is just wonky re: 4 and difficult to orient for a match.

Re: Stitching – A Python package for fast and robust Image Stitching (Panoramas)

#28

Post by bmh »

O5vYtytb wrote: post #22

Wondering if anyone has examples/ideas for how to do this with video? I have two cameras (GoPro) that I use to record athletic games on a 20ft tall tripod, and I want to automatically stitch them together for easier analysis of games. I think I can use a tool like this to find the stitching parameters for the first frame and then apply it to all future frames, assuming the camera doesn't move?

Yes, this would definitely work, so long as the two cameras have sufficient overlap. If you were to use OpenCV's stitching code, then you could run the first few phases of that on your initial photo pair, which determine the camera angles, and then save those angles.

Then, for every video frame, you could skip the photo angle computation, and just run the imagine stitching logic. The stitching_detail code is very readable, and quite easy to hack for experimentation.

Re: Stitching – A Python package for fast and robust Image Stitching (Panoramas)

#29

Post by kwon-young »

ahns wrote: post #26
kwon-young wrote: post #5

In my case, my dad needed a Gui for stitching microscope images and he told me that none of the panorama stitching Guis were working for him. I found out that the out of the box opencv Stitcher [1] class is perfect for that but nobody seems to have made a GUI out of it. So, I've spent two days making an extremely simple proof of concept of a Qt Gui [2]. The majority of the time was spent trying to use GitHub Action t…

For microscopy images, have you tried ashlar? https://github.com/labsyspharm/ashlar It may help to have the microscope stage positions available in the OME metadata.

I did not know of this project. I suppose it did not come up in my research sinve I was looking for simple Guis that my dad could use.

His setup only has a simple microscope camera that can stream a video to an old windows xp pc with a hardware/software combination...

Re: Stitching – A Python package for fast and robust Image Stitching (Panoramas)

#30

Post by kurupt213 »

bmh wrote: post #20
StephenSmith wrote: post #17

I'd love someone with more CV experience to explain why this fails on my use case? (four image zip) https://drive.google.com/file/d/1gTZWlKmS4ZtEZDK8OjjLeGN_V0F...

A panorama is built by stitching together many images taken from the same viewpoint. The 1st critical thing you need to know, is that the camera may not move. It may only rotate. If the camera moves a tiny bit, that's generally OK, but there will be stitching artifacts. To be really precise, the entrance pupil of the camera shouldn't move, but this is quite hard to get right. The 2nd thing, is that the stitching algo…

Nice explanation
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