Google Maps Tile Cutter forcing white background - leaflet

I am using leaflet. Since I cannot use image-overlay due to memory usage and zooming being slow on some browsers I would like to use two tile-layers.
This seems to work perfectly, but the only thing I cannot fix is getting my tiles to be transparent. Whenever I cut them in Photoshop by using Bramus' tile cutter script it automatically adds a white background.
Does anyone know how to solve this?
https://www.bram.us/2012/04/23/photoshop-google-maps-tile-cutter-script/
That's the script I am using.
So basically what I want is the tiles being cut exactly as this script does, but with a transparent background.
I tried removing the white background by using ImageMagick but that still leaves me with some pixels in various shades of grey around the black area's unfortunately so that is not working either.
for /R "C:\Users\<USERNAME>\Desktop\map\name" %I in (*.png) do magick "%I" -fuzz 0.3%% -transparent #FFFFFF "%I"
Original image
After ImageMagick - added green BG for reference
After ImageMagick original
I tried adding -trim, but then I still have edges around my arrows, and sometimes (see original image below) it even deleted the gray area with the black top-border.
Anyways, is there a alternative for my Photoshop script so I can still generate tiles but transparent? I couldn't really find one.

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Unity 2D: Make an image completely black

I need to make a copy of an image and make it completely black (silhouette) at runtime. Just changing the color to black doesn't do the trick, for a reason Unity makes some lines transparent:
Its because your image is not completely filled and has gaps where those "lines" can be seen

Unity - Render Texture from Camera's targetTexture produces seams

I am attempting to render a specific section of my scene using a separate camera, and a render texture. That object is on a separate layer that the main camera is not rendering, but a separate camera is. The secondary camera has a target texture set to be a render texture that I have created. Everything is working as intended except for the fact that the object, when rendered to a texture, has a bunch of seams that are not present when rendering directly to the screen.
What it looks like when rendered directly to the screen:
Correct
What it looks like when rendered to a texture, and then displayed on a quad in the scene:
Incorrect
Notice how the second image has a bunch of transparent "lines" in between the sprites where there shouldn't be any.
I am using a basic transparent shader to display the render texture on the quad (since the background isn't part of the render texture, just the black crowd part). I have tried a number of different shaders, and none of them seem to make a difference.
The render texture's settings are: Width: Screen.width Height: Screen.height Format: RenderTextureFormat.ARGBFloat;
Unity Version: 5.2.3f1 - iOS Platform
Note: The reason I am doing this is so that I can apply a "Blur" image effect to the texture, and make the crowd in the foreground appear to be out of focus. Any alternative suggestions for how to do this are also welcome.
I'm not quite sure -- but it almost sounds like you have line ghosting. You may want to give this a read and let me know if that's what you're dealing with or not:
The reason for this is due to how the texture image was authored, combined with the filtering that most 3d engines use when textures are displayed at different sizes on screen.
Your image may have coloured areas which are completely opaque, coloured areas which are partially transparent, and areas which are completely transparent. However, the areas where your alpha channel is completely transparent (0% opacity) actually still have a colour value too. In PNGs (or at least, the way Photoshop exports PNGs) seems to default to using white for the completely transparent pixels. With other formats or editors, this may be black. Both are equally undesirable when it comes to use in a 3d engine.
You may think, "why is the white colour a problem if it's completely transparent?". The problem occurs because when your texture appears on screen, it's usually either upscaled or downscaled depending whether the pixels in the texture's image are appearing larger or smaller than actual size. For the downsizing, a series of downscaled versions get created during import. These downscaled versions get used when the texture is displayed at smaller sizes or steeper angles in relation to the view, and is intended to improve visual quality and make rendering faster. This process is called "mip-mapping" - read more about mip-mapping here. For upscaling, simple bilinear interpolation is normally used.
The scaled versions are usually created using simple bilinear interpolation, which means that the transparent pixels are mixed with the neighbouring visible pixels. With the mipmaps, for each smaller level, the problem with the invisible mixing with the visible pixel colours increases (with the result that your nasty white edges become more apparent at further distances away).
The solution is to ensure that these completely transparent pixels have a colour value which matches their neighbouring visible pixels, so that when the interpolation occurs, the colour 'bleed' from the invisible pixels is of the appropriate colour.
To solve this (in Photoshop) I always use the free "Solidify" tool from the Flaming Pear Free Plugins pack, like this:
Download and install the Flaming Pear "Free Plugins" pack (near the bottom of that list)
Open your PNG in photoshop.
Go to Select -> Load Selection and click OK.
Go to Select -> Save Selection and click OK. This will create a new alpha channel.
Now Deselect all (Ctrl-D or Cmd-D)
Select Filter -> Flaming Pear -> Solidify B
Your image will now appear to be entirely made of solid colour, with no transparent areas, however your transparency information is now stored in an explicit alpha channel, which you can view and edit by selecting it in the channels palette.
Now re-save your image, and you should find your white fuzzies have dissappeared!
Source: http://answers.unity3d.com/questions/10302/messy-alpha-problem-white-around-edges.html
Turns out that the shader I was using for my scene was using "Blend SrcAlpha OneMinusSrcAlpha" for some reason, when it should have been using "Blend One OneMinusSrcAlpha". This was causing objects with alpha less than 1 to make the objects under them become semi-transparent as well exposing the camera's clear colour background.

Incorrect white matte behind antialiasing on imported sprites

I'm importing a sprite into Unity, and adding it to a Screen Space Overlay canvas to use for a UI.
The image I'm importing looks exactly as I want it, but in Unity the anti-aliased edges look like they're going to a white background color, instead of just fading over whatever is actually behind them.
I'm using these import settings:
I'm using a default UI/Image component to add it to the canvas.
This is the image I'm importing - it's a 32 bit PNG exported from Fireworks: (also shown over a black background)
Just to confirm, this looks fine everywhere else in Unity, preview panels, pickers etc. I am packing this sprite using the built in Sprite Packer if that changes anything.
And the final result:
How can I get rid of these artifacts on the corners?
The problem was the RGB values of the transparent pixels. By default they are white, and any scaling operations cause this white color to be blended with the partially transparent pixels.
I essentially made a slightly larger version of the button background shape, put it in a layer behind everything, and then wrote back into the alpha channel making it transparent. This means that the neighboring pixels are then the same color as the partially transparent ones.
The end result:

Unity sprites don't render properly

I recently came across a problem I can't solve which involves not being able to draw my sprites properly. I have tried a lot of different things and couldn't find any solution.
Here is how the image should look like in unity:
And here is how it actually looks like:
If someone could tell me how to fix this, I would be very grateful.
Presumably the top image is a screenshot of your image manipulation program, many of which use the chequerboard pattern to mean transparency. As such, the image you have exported is a gradient going from almost solid white at the bottom to transparent at the top. This is why the image appears as such in Unity.
Also, if you're wondering why the image appears as though it has bands of different colours, this is due to a problem called colour banding. This can be fixed by using a technique called Dither (which adds some noise to the image), but how you do so will depend on which image manipulation program you are using.

php gd library to reveal background image

I have two identical sized images that I would like to work with. One image is in color, the other is in black and white. I need assistance on stacking the color image directly over the black and white image. After that, I would like to be able to remove sections of the top photo to reveal the image underneath.
Can someone point me in the right direction on how to accomplish this?
Here is something that may help:
http://forums.devshed.com/php-development-5/how-do-i-merge-various-images-into-one-using-gd-502604.html
Especially the part that talks about adding watermarking.
You will have to add transparent areas to the top image before combining them.
lee