V1.3 - Control Points Editor
- 1 Innovative Concept
- 2 Interface Description
- 3 The Toolbar
- 4 Selection Windows
- 5 Viewer Toolbar
- 6 The Editor Grid
- 7 Options
Yet another Autopano Pro innovative concept - the Control Points Editor - will allow you to manipulate your panoramas with great ease, in a very efficient way. The general idea behind the Control Points Editor is to be able to manually edit Links and Control Points to achieve an optimal alignment of the source images. In some cases the automatic stitching mode will have trouble aligning the images, and will even exclude some of them from the panorama. This problem can easily be corrected using the Control Points Editor.
Clicking the Control Points Editor button in the Panorama Editor will overlay a grid of links and labels over the panorama preview in the Panorama Editor. This is the Editor Grid and it is formed by a network of white points (images) connected by lines (image links). A new window will also open - the Control Points Editor. This window will allow you to edit the control points by selecting either the links (i.e. bounds between two or more images), or the individual source images currently included in the panorama. The control points are used by Autopano Pro to arrange the images within the panorama.
- Used to add a picture to the panorama.
- Used to delete the selected pictures, links or control points.
- Gives information about the global stitching quality of the panorama.
The Image List is closely tied to the Link List and the Control Points List. By selecting an image you will effectively be able to visualize the links and the control points this particular image shares with the other images inside the panorama.
This feature will allow you to quickly see if an image is correctly bounded to another.
Tip: Selecting all the images will allow you to display the global Grid of the panorama.
The Link List is closely tied to the Image List. Meaning that when selecting one or more images the list will display the links shared by the selected images.
Note: A smaller RMS value indicates a higher quality link.
Control Points List
The Control Points List is closely tied to the Image List. This means that when selecting one or more images the list will display the control points shared by the selected images.
Note: A smaller RMS value indicates a higher quality control point.
- Vertical/Horizontal orientation: /
- Panorama Optimization:
- Add control points:
- Delete control points:
- Automatically add links/control points:
- Automatically delete bad control points:
- Automatically add and delete links/control points:
This icon initiates the panorama’s optimization calculations. This step will take in account all the changes performed on the panorama and adjust it to the new constraints.
This operation can be configured in the Options Dialog.
This icon will allow you to automatically add control points. All you need to do is to define a common area on each image and hit the keyboard Enter key.
- A smaller area will lead to a higher accuracy in the control points placement. In some cases however, it is possible that adding control points fails (i.e. no new control points are appearing). In such a case try a smaller area.
- Adding control points implies the creation of a link between the images.
This icon will allow you to delete control points. To do so, define an area on one of the displayed images. All controls points inside the created area will automatically be selected. Next, click on the icon or use the keyboard Delete key.
Note: If you delete the totality of the control points shared by two images, you are also deleting the link between those two images.
This button allow for a geometry analysis of the panorama in its current state. The geometry analysis is used to find the existing overlaps from the source images current locations. For each overlapping area found, the software simulates the adding of control points, just like you would have done it yourself by defining the two zones. You can configure the way the software will be adding the links in the Optimization Settings Dialog.
The screen capture on the right illustrates this concept. The overlaps analysis forces Autopano Pro to automatically add links in the center of the panorama.
The main appeal of this function is that its use generally leads to an increase in the panorama's quality. The number of links between the images is increasing and the individual links are then becoming stronger. But it’s not always the case. In the case of a 360x180 panorama, this analysis is less efficient at the poles.
Also, geometric analysis will add CPs on clouds and other moving objects, so its really not a good idea for an outdoor 360x180. There is a local geometric analysis that can be used on each image that is better for 360x180 panos.
This icon will allow you to delete control points on all images following two methods:
- Error threshold method: all points over a maximum error threshold will be deleted.
- “N” best control points method: We keep the “N” best control points per link.
Each method has its own upside and downside. I personally have a tendency to give a plus to the second method as it will never break a link (i.e. even if all control points are really bad, some will always remain). This is not the case with the Error Threshold method as it can very well delete all control points from a link.
The Editor Grid
The goal of the Grid is to visualize the links existing between the images and to give information on their quality. This Grid is displayed on top of the panorama preview and allow for a rapid visualization of the existing links, their quality, missing links, etc. It also allow for a new selection of the images and the links.
- Selecting an image:
represents an image and its index in the Image List.
When selecting an image, the Editor Window will highlight the selected image along with some red lines showing you which images are linked to the current selection.
In the example given on the right, the selected image (#13) is linked to the images 3, 4, 5, 6, 12, 14, 16 and 17. And if we look closer in that area we can see that there is no other image present; Autopano Pro found all links!
- Selecting Multiple Images:
In order to edit the control points shared by two images, all you need to do is select a pair of images. Click on the first image to select it, you can then select the second image by holding the keyboard Ctrl key down and by clicking on the second image. The Preview Windows will refresh and display the selected images. You can now add or delete control points.
- Selecting a Link:
represents a link with a RMS value of 1.79 and a number of control points of 47. When selecting a link, the Editor Window will highlight the link itself, along with the two images located at each extremity of that link. A red line connecting the two images is also displayed. A color code is used to quickly identify good and bad links:
- Green (RMS <5): Good quality link.
- Orange (RMS between 5 and 10): Medium quality link.
- Red (RMS > 10): Poor quality link.
If you find yourself with red links (i.e. poor quality links) it means you have bad control points. The control points must be edited. It is possible that the images do not relate to each other. In such a case, delete the link.
- Selecting Multiple Links:
It is possible to select multiple links at once. The Grid display will then change to reflect the selection.
Optimization Settings determine image positioning, the quality of CP pairs, global RMS and the overall panorama quality. It is important to understand that the Optimization Settings have two instances - Global, set from here, and Local, set from the Control Points Editor. Whatever you set in this dialog will be applied to every newly created panorama, unless overridden by its local settings.
- Optimisation: By default, these two options are checked and this setting should work fine most of the time. Turning those off will really speed up the detection of large panoramas (hundreds of files).
- Strong algorithm: Turn on/off the use of a stricter algorithm while optimizing after panorama detection.
- Lens distortion: Turn on/off the lens distortion correction logic.
- Geometry analysis: Geometric analysis automatically looks for control points in all images. This option defines the behavior of the Add control points using geometric analysis button in the Control Points Editor. As this analysis relies on images already pre-positioned, Autopano Pro can concentrate on the seam areas between the images. Three modes are provided:
- Find control points where none exist: Look for control points between overlapping images that have no Image Link created. Use this mode when there are some missing image links.
- Find control points everywhere and merge with old CP: Look for control points in every image, then add the newly generated points to those already present. Use this mode when there are too few control points in the panorama overall.
- Find control points everywhere and remove old CP: Look for control points in every image, then remove the current points and use only the new ones. Use this mode when the overall control point quality is weak.
- Bad control points cleaner: This function is like a filter applied to all control points, leaving only the best ones. This option defines the behavior of the Clean bad control points button in the Control Points Editor. Two modes are provided:
- Keep control points below this error (RMS): Remove all points that have a RMS above the selected value. Gives better quality, but with badly positioned images can remove most of (or all) control points.
- Keep the N best control points: Leave an exact number of points per image pair, removing only the worst ones. Usually the best mode with hand-held panoramas or difficult cases.
- Auto fine tuner: Allow you to trigger the following functions automatically:
- Use geometry analysis
- Use bad control point cleaner
Note: Use geometry analysis is launched before Use bad control point cleaner
- CP detector quality: This options enables you to choose the quality of the control points detector. By defautlt, it is set on "standard", which is a good compomise between speed and detection quality. You can also set the number of control points to be detected.