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Messages - nprp

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General / Re: Primary channel and masks at the orthomosaic stage
« on: November 12, 2021, 12:32:57 PM »
Hi Alexey,
I've looked again at the materials.

It's clear now that MS use independent masks at orthomosaic stage. However, at the aligning stage some areas can be omitted because of masks and that may result in holes at the orthomosaic.

Then, I suppose, in order to hide overexposed areas, masks should be applied after aligning stage.

General / Primary channel and masks at the orthomosaic stage
« on: November 08, 2021, 12:13:58 PM »
I am processing multicamera system and some images are overexposed. There is certain chance such areas are not overexposed in neighbouring images. My idea is to apply masks to overexposed areas so that they won't be used in orthomosaic.
The question arise: does MS use EACH channel masks at orthomosaic stage or it only uses PRIMARY CHANNEL masks to all the channels?

As I can suppose from seamlines, MS only uses primary channel masks.
Is there any option to independently apply masks to separate channels at the orthomosaic stage?  Masks are generated for each image, separate channels are stored in separate images.

I have a backup plan - to generate 5 single-channel orthos (with different primary channels) and then merge outside MS but I think it is an interesting issue to discuss here.

I've just updated to 1.7.4 and the problem is gone!  8) Thanks.

For a record: I had been comparing histogram values and general appearance of the orthomosaic after applying different formulae.

I've just noticed that Raster Calculator delivers incorrect result in case there is at least one floating point multiplier in the transform formula.

For example, let's compare the following:
1. 1.5*B1 vs (3/2)*B1   
(1.5*B1 results the same as B1 )

2. 2.99*B1 vs 3*B1   -  I can see that 2.99*B1 results the same as 2*B1

General / Re: Small Circles in ortophoto
« on: February 11, 2020, 10:11:13 AM »

You could atenuate this effect by using average, instead of mosaic... but this often blurrs the orthoimage.

I would recommend to use simple masks where the center spot is hidden. It works well and you still can use mosaic blending.

General / Re: Ortho GSD with Images at Different Resolutions
« on: February 11, 2020, 10:06:40 AM »
Metashape will allow
but GeoTIFF format do not assume several resolutions in one file.

You can process it altogether and even export in best resolution (which will be equal to the resolution from the lower flight) but areas covered only with higher flight will contain interpolated data.

In other words, you will see what you want but GeoTIFF as a container will consist of lots of useless extra pixels. Not sure with KMZ.

I tried to align microphotos from optical 15x microscope and even at this zoom it wasn't just a few clicks

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