how to generate an image by repeating a column extracted from an image ?

[did78]

Hello, I'm looking for a way to create a new image based on a column extracted from this image, repeated on the whole frame. So that the new image created would be a succession of different lines, each line consisting of the pixel selected in the column.

In other words, to simulate a sensor which has its horizontal readout broken and displays the same pixel over each line 

(not sure it's very clear)

any idea to do that ?

[Alfred]

50 minutes ago, did78 said:

I'm looking for a way to create a new image based on a column extracted from this image

Did you mean to attach an image?

51 minutes ago, did78 said:

(not sure it's very clear)

I’m afraid it’s not at all clear to me at present!

[NotMyFault]

There are many ways to do this.

 

In Photo: make a selection of the column. Create new pattern layer from selection. use a rectangular shape to mask the pattern layer.

[NotMyFault]

Even simpler:

1. new document
2. add pixel layer
3. use fill tool. Set mode to "bitmap". Select your image file. The last column will be repeated (or all edge pixels).

The next V2.1 will allow to set the "extension mode" and resample mode. What you need is "repeat". In V2.0 it seems to be always "repeat" and "bilinear"

 

The screenshot below is a bit tilted - just to show this is possible.

[David in Яuislip]

I understand this to be that every pixel column is to be the same, if that's correct:

Make a marquee one pixel wide
Copy
Paste special/DIB - it'll end up somewhere weird so reposition to x=0, y=0
<ctrl>J
Change x value to +1
<ctrl>J lots

[David in Яuislip]

Forget that, new pattern layer from selection

[did78]

Hello,

Thanks for all these quick responses !

That's exactly what I try to do

I will try  (I'm not an experienced user)    

 

[did78]

Thanks David,

Works great + very simple for a newbie

 

[thomaso]

A different workflow would simply stretch a cropped part of the image, for instance:

 

[John Rostron]

To stretch the cropped result, use Document > Resize Document, then click on the lock icon  (to unlink the height and width), then enter your desired width in the Width box. OK to confirm.

John

 

[thomaso]

7 hours ago, John Rostron said:

To stretch the cropped result, use Document > Resize Document, then click on the lock icon  (to unlink the height and width), then enter your desired width in the Width box. OK to confirm.

To me it appears easier & more flexible to use a cropping Rectangle Layer … instead of Document > Resize Document. – Or do I miss something?

[John Rostron]

On 3/27/2023 at 5:32 PM, thomaso said:

To me it appears easier & more flexible to use a cropping Rectangle Layer … instead of Document > Resize Document. – Or do I miss something?

On the few occasions that I needed to do this, I did it as described since it seemed the most obvious way, especially as I have never heard of a cropping rectangle layer.

John

[lacerto]

Obsolete.

[thomaso]

6 hours ago, lacerto said:

The rectangle method keeps sharp antialiased edges while its resampling method seems to be bilinear.

I might be wrong but doesn't it rather matter that vector generally gets treated different than pixels – and thus the vector cropping mask above causes different edges if stretched?

For instance two 50x25 px objects, each placed at X = 0.5 px, then stretched to 500 px width (within the document, not via "Resize Document…" )

By the way, this reminds me to an earlier thread where a choice for the resampling method of object scaling was logged as improvement in V1. (I can't try if it's implemented in V2)

On 8/1/2022 at 2:26 PM, Dan C said:

On 8/1/2022 at 12:49 AM, thomaso said:

but how about for single objects on a page?

Unfortunately however I don't believe such control exists for a singular layer, though I will be sure log this as an improvement with the developers as I can certainly understand the use case of such a function 

[lacerto]

Obsolete.