ArcGIS Pro and ArcMap usually stretch geo tiff. We have some large tiff files and some of the sections do not look good when stretching is applied. I usually open them in QGIS and they look very useful without any stretching. In ArcMap, they are an options to disable gamma stretching which shows a similar-looking raster as QGIS as shown in the image below.
I am trying to do the same in ArcGIS Pro 2.8. I am going to the symbology option of the raster and selecting the stretch type to "None". However, there is no option to disable the gamma stretching. The gamma values are 0.2,0.2,0.2 and making them 0,0,0 do not work.
Any known option to disable the gamma stretching in ArcGIS Pro?
Related
I have no experience on any image processing/editing tool. And I am doing a project, which requires me to use different shapes. I could create different shapes using visio. But however not able to get rid of white background behind. I need only shape not squared white background.Tried online out of my ways but not successfull.
Any help will be greatly appreciated.
Thanks,
Ganesh
Absolutely any image file has to be contained within a rectangular frame, this includes png and SVG.
Some image file formats can have what are called alpha channel backgrounds this allows you to see through transparent areas.
What you want to do is remove the white background to expose the alpha channel background in Photoshop (or similar tool) which can then be saved out as transparent.
For example in Photoshop:
If you open this image directly and have no other layers, double click the layer that says background and OK the confirmation box. This turns your flat image into a layered image
Select the magic wand tool and ensure you have a high tolerance set (3)
with the wand selected click the white area to bring up a marquee around your selection (the white background) and hit delete to remove it.
Your image should now have a chequered background which is the transparency showing through.
If you now go to file > save as and select png, your image should now be saved out with an alpha background.
Please note: There are further optimisations to make if this is for web, including file formats and file size but that is beyond the scope of this question but I encourage you to read up on the Gif format and it's restrictions, the difference between 8bit and 24bit pngs and how to use SVG.
You can do it pretty simply at the command-line using ImageMagick which is free and installed on most Linux distros and is available for OSX and Windows.
Basically, you want to make your whites transparent, so you would do
convert shape.png -transparent white result.png
If your whites are a little bit off-white, you could allow for some variation with a little fuzz as follows:
convert shape.png -fuzz 10% -transparent white result.png
I added the checkerboard background just so you can see it on StackOverflow's white background - it is not really there.
By the way, you may like to trim to the smallest bounding rectangle while you are there:
convert shape.png -fuzz 10% -transparent white -trim result.png
By the way, you can also draw your shapes with ImageMagick:
convert -size 150x150 xc: -fill none -stroke "rgb(74,135,203)" -draw 'stroke-width 90 ellipse 0,0 80,80 30,80' arc.png
See Anthony Thyssen's excellent examples here.
I have a question regarding high quality exports from spotfire to PDF.
I read on Spotfire support page that to obtain highest quality exports for visualizations you should select vectors (instead of rastar). They still provide better quality than rastar graphics with maximum quality (5 out of 5). However, when I export these images to PDF, the quality is relatively low. Is there a way I can increase the quality? Would it help to select e.g. PPT exports? I think manual screenshots are still better in quality, but more timeconsuming. We are looking for end-user friendly interface.
Furthermore, if your table is longer and you use slider, what is the recommended way of exporting such a graphic?
Thanks a lot.
raster graphics are generally lower quality. jpeg, for example, is a raster format, where each pixel in the image is coded to a specific color; if you resize the image, it becomes blurry or loses detail.
vector format defines points, lines, and shapes that make up an image. when you scale the image up or down, there is no guesswork trying to blend pixels -- instead the points are recalculated to whatever size. for example, fonts are usually vector format, which is what allows them to be scaled up or down to any size.
the quality of the vector image may be low due to the zoom settings on your PDF viewer (although the image can be scaled to any size, your screen still relies on pixels to display it), but it is the most possible detail. if you zoom in you will probably see an increase in quality.
manual screenshots probably look "best" because there is no scaling or resizing involved. you can export to PNG (raster) image format to get the same effect.
you will not see an increase in quality by exporting to Powerpoint. either you will export it as a raster image to a PPT slide (default settings) or you will export it as a vector using the "As Editable Image" checkbox (which allows you to modify the image in PPT).
what is your end goal? Spotfire is best suited for viewing in the Desktop or Web Player applications, otherwise you lose a lot of features like interactivity, (potentially) live date. if you have to make a lot of exports maybe it is easier to simply provide a link to the analysis?
to your final question, Spotfire is not very good at table exports. I have had some luck with increasing the page size (A4 or A5, for example) and using Landscape over Portrait. again, I recommend to view it in the application.
I'm trying hard to nicely blur a red circle but everytime i get gradient levels of red and the image looks choppy.
Before:
http://i.imgur.com/6yzMhFI.png
After:
http://i.imgur.com/2dZl4ph.png
How i can acheive a smooth blur ?
If you are referring to the visible circles that separate the gradation levels, that is called banding Here are some ways to fix that:
Increase your document's bit level from 8-bit to 16-bit
This will increase the amount of colors your file can represent, creating more colors that can be used to represent the gradient, making it smoother in appearance.
In Photoshop navigate to Image>Mode>16-Bits/Channel
In GIMP 2.10 (or higher?), navigate to Image>Precision>16 bit..
Display or system settings might be unable to display enough colors
If changing the bit depth does not fix the issue then you might have a hardware or system settings issue.
If it's a hardware issue, your monitor might not have the capability to display enough colors to render the gradient smooth
If it's system settings you will need to go to your operating systems color depth setting, usually located under the system's display settings. It could say something like Millions of Colors, or True Color (32-bit).
The last thing related to settings is that you have a bad color profile set in your system or in your image editing software. It's beyond the scope of this answer. If you don't know how to color calibrate your monitor, then it most likely isn't this and you can skip this.
If you have to have 8-bits
If you absolutely have to keep your document in 8-bit color space then you will have to use dithering or add some noise to your image to confuse the viewers brain into seeing a smooth gradient.
Noise or dithering will confuse the viewers brain into seeing a smoother gradient by setting some focus on the imperfections of the noise/grain/dithering. This doesn't exactly answer your question, but it is about the only option you have if you keep your ultra smooth gradient in 8-bit mode.
Good Luck!
I think you are applying the Gussain-Blur to the entire image try to Select the red circle and apply the Gussain-Blur filter to it
I'm importing my stimulus from a folder. I would like to make them bigger *the actual image size is 120 pix (height) x 170 pix (width). I've tried to double the size by using this code in the PsychoPy Coder:
stimuli.append(visual.ImageStim(win=win, name='image', units='cm', size= [9, 6.3],
(I used the double number in cms) but this distorts the image. Is it any way to enlarge it without it distorting, or do I have to change the stimuli itself?
Thank you
Just to answer what Michael said in the comment: no, if you scale an image up, the only way of guessing what is in between pixels is interpolation. This is what psychopy does and what ANY software would do. To make an analogy: take a picture of a distant tree using your digital camera. Then scale the image up using all kinds of software. You won't suddenly be able to see the individual leaves since the software had no such information as input.
If you need higher resolution, put higher resolution images in your folder. If it's simple shapes, you may use built-in methods such as visual.ShapeStim and it's variants: visual.Polygon, visual.Rect and visual.Circle. Psychopy can scale these shapes freely so they always stay sharp.
I'm working on a simple iOS game that's always drawing 5 to 10 layers of 32bit png images which requires enough memory to crash on the ipod touch 4g when retina enabled. On other devices it works just fine. I'm not even getting memory warnings. So I was trying with lower quality images, like RGB5_A1 format, but it looks really bad because I need alpha transparency and lots of gradients.
Since all the images are exports from Illustrator I was thinking that maybe i could just export a vector image and draw in on iOS. From what i was researching hardly anyone tried this and the only option I've come across was to implement a SVG parser for Quartz.
Did I miss anything?
Also I'm worried about performance, but I couldn't find any benchmarks.
Without knowing specifics of your game, I'm going to make a few assumptions based on normal use...
You are not going to want to use straight vector graphics for this. Stick with your raster graphics.
If you are talking about 32 bit color space for your PNG images, then you need to scale back. iOS uses 24 bit images and that includes 8 bits each for red, green, blue, and alpha. As it stands, you have an extra byte for every pixel shown.
If you are using Adobe products, import the Illustrator file into Photoshop and use the "Save for Web..." option. Choose PNG-24 and you'll be all set.