Topics

1

General / Any way to disable internal compression entirely?

« on: July 11, 2018, 05:47:24 PM »

I have been able to identify artifacts in the final ortho products that are due to the use of jpeg compression internally on the generated mosaics. The input frame data is losslessly compressed, and the exported tif files have lossless compression as well, but the internal tif tiles (by looking through the Photoscan project diretory) use jpeg compression.

In 1.3.5, the Project Compression slider can be set to zero, but it doesn't remove the jpeg compression artifacts. In 1.4.x, the setting is entirely gone.

Is there any way to force Photoscan to not use jpeg compression internally?

This significantly negatively impacts the accuracy of resulting NDVI images. The jpeg blocking is very apparent.

2

General / Force selection of pairs to solve?

« on: June 26, 2018, 11:32:58 PM »

If I have the ability to select pairs I want to Photoscan to use, can I force it to only use those pairs for feature detection, matching, and camera alignment?

I can verify that the pairs being selected would provide sufficient connectivity. It would be important that only those pairs get used, and no others.

This is because Photoscan fails to align datasets that frequently have either time or location coincident images where the pair matches do not have good 3d information (no baseline).

Alternatively, is there a way to force Photoscan to not attempt to align time or location coincident images? I understand it probably doesn't have image acqusiition time, but a simple way to do this for location would be to not use any pairs that are not sufficient far enough away from each other.

3

General / How to use pre-aligned multiband images?

« on: June 26, 2018, 11:29:46 PM »

I'm attempting to process a multispectral dataset using a set of tif images that can either be multi-page or multi-channel (It appears only multi-page is supported?).

Each page/channel is previously band aligned, so only the first/master channel would need to be used.

However, it appears in any multispectral chunk setup, regardless of multiplane or multilayer, it appears to be detecting features and attempting to realign all the other channels.

Is there anyway to force Photoscan in the scripting interface to stop doing this, and only use the primary channel for camera alignment?