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Libgdx - 3 images in a group, best practice - also overdraw

I am trying to write a card game, that will have an image in the middle, a coloured border and potentially a symbol in the top left. I am using libgdx and a stage/scene2d.
The image will change depending on the suit (these are not your normal 52 deck type of cards), the border colour will change to match the suit, though this colour can be pre determined by the user so I can't pre-save coloured images (though I guess I could pre save about 15 diff colours and give the user a choice of 15) and the symbol will only be on some cards and not others.
As you can see from the two images I've added I have two diff images, border colours and symbols.
My question is relating to groups and overdraw.
1) I presume I should set up a group with 3 images in, and I'm hoping having this won't slow my game down as I will have potentially 30 cards on screen at once and 30 groups with up to 3 images in each could be a lot to draw. Is this right and will LibGDX be able to handle it fine?
2) How should I do the coloured border? Should I have the entire card a coloured rectangle and the image drawn on top? Would the draw method be trying to draw the coloured section underneath the image and thus wasting GPU/CPU time? A friend of mine said I could just have a white image, and then set the colour using RGB values in the code? Is this possible? That would mean I could only have a single jpg which would be much better for apk size.
3) Or should I ignore using a jpg image and try and draw the coloured square using ShapeRenderer?
Thanks, I hope these questions aren't too many in one post.

Of course it will not slow you game - 90 (30 groups x 3 textures) sprites on screen are like nothing for (I guess) every framework - so LibGDX will do the thing also.
Although it does matter how these graphics will be stored! Please use one TextureAtlas with all textures instead of many textures in many files - you can prepare the Atlas by using TexturePacker (for a basic usage like this free version will be ok).
The reason of this is that if you are using many single Textures LibGDX needs to switch graphic in GPU bufor (maybe it is not perfect term) before rendering each of them - if you have one big texture (including others) it does not need to switch anything because nothing changes in the buffor.
To get more information about using TextureAtlas take a look at the manual
Yes you can "color" the Actor (like Image) by using for example
actor.addAction(Actions.color(new Color(1f,1f,1f, 0.2f), 2f));
another approach is to have 1px x 1px texture of every color (packed in your Texture Atlas) and just to change it's size. There no reason to keep full size singe-colour textures since it is great vaste of space and memory.
It is generally not good idea to use ShapeRenderer - of course it is helpful sometimes but drawing sprites has a greater performance.
You are generally a little bit too scared about performance but if you want to save your CPU avoiding ShapeRenderer seems to be good idea.

Need a way to get the Text in the Image in Black/white

I have a colored textual Image to be in black and white.
Specifically the text to be in black and background to be in white for whatever colored it might be
I am using JAVA to perform this operation.
Can anybody help me out to with a code snippet or point me to a discussion which is useful.

if you want to develop your own converter RGB to Black/White, please check Java - get pixel array from image . Here you import a image, access the pixel and with a specific threshold of the color you can decide to convert to black or white.
Or you use http://www.imagemagick.org/ as commandline tool (with api http://www.imagemagick.org/script/api.php).
Regards

Java texture png modificaiton

I'm trying to make a simple java game.
I have some png file that i want to draw, but first i want to make some modification on that png. I would like to take a png, and delete to background some parts of it and add some colored lines..
For my game im using libgdx.
I dont know what to use for this, so i can search on google about it and learn.
Few hints, about what functions i should use could be awesome, Ty.
P.S. I tryed to search on internet before post here, but i didnt find something that could help me, probably idk what to search.v
Edit:
I found Pixmap from libgdx, but i can delete to background. Any advices ?
Edit2:
i want to load this texture
multiplicate when needed (no problem here)
and delete some parts of it, to background, so it will take this shape:
by using pixmap, when im drawing background over it, nothing is happen, because its draw over, not instead of.
What i could make, was using pixmap to draw the top part, that i want to delete, and manualy delete it using external programs:

I think you might want to look at a "mask" image. There are some approaches listed here: https://github.com/mattdesl/lwjgl-basics/wiki/LibGDX-Masking
Alternatively, you could use create a mesh that encodes the "ground" (with the bump) and then texture it. OpenGL would take care of truncating the edge of the mesh. Try: Drawing textured polygons with libgdx
Another approach is to just draw the dirt texture on the full screen, and then draw the "background" over it. You will need to make pixels in the "background" image transparent so the dirt will show through. Whatever pixel editor you are using should be able to do that. Alternatively, pick a "key" color and convert those pixels to transparent when you load the image as a pixmap.

I don't know if this question is serious, but you cannot do what you're asking in Java. You need a photo editing software such as Photoshop or GIMP.

Java: Taking a Image and turning it into Black in White with RGB

So I am doing a group project for my programming class, we are makeing a photo editing program and one of my parts of the program is taking the image and turning it into black and white using rgb. I was wondering what would be the best value or way in RGB to achieve black and white?

I would recommend letting the Java 2D library worry about the conversion:
create a greyscale BufferedImage (BufferedImage.TYPE_BYTE_GRAY);
get a graphics context by createGraphics()
ensure that colour rendering is accurate on that graphics context: call setRenderingHint(RenderingHints.KEY_COLOR_RENDERING, RenderingHints.VALUE_COLOR_RENDER_QUALITY)
draw the colour image you want to "convert" to the graphics context
If you do the conversion "manually" and you want to do it as accurately as possible, then you need to take into account that the eye is more sensitive to certain colour components than others. (If you want a "rough and ready" conversion, you can average the colour components, but this isn't strictly speaking the most accurate conversion.)

For each pixel, you can convert the RGB to HSB (using Color.RGBtoHSB), set the saturation to 0, and convert back to a Color instance using Color.getHSBColor.

Wikipedia actually has a good piece about how to perform the transformation once you have the RGB colors.

Hey , this page has many Java Image filters which are freely available for download.All filters are standard Java BufferedImageOps and can be plugged directly into existing programs.The GrayscaleFilter can convert the image to black and white

Using java.awt.image.ColorConvertOp with a gray destination ColorSpace is very efficient. There's an excellent example here.

How to get the text background color (RGB values) of a pdf file?

does anyone know how I can find out the text background color (RGB) of a pdf file? Thank you!

There is no background.
PDF is a print media oriented, and background is always white. An object (drawing, image etc.) is beyond the text and makes "background". You have to detect this object and get color of it (this can be not easy too, due to different color spaces).

If the PDF contains layers you might be able to think about a background layer but otherwise there is no real concept of a background image - it is what you choose to interpet.
A PDF is a vector image which is drawn and you see the finished article.