I'm trying to create icons (.ico format) with ImageMagick with only partial success. I can't get the resulting icon to have any transparency. I've tried many things like -alpha Background, -quantize transparent, -transparent-color, but I just can't get it working.
I can get it working if I don't reduce the colors -colors 256. It's with that reduction where I lose the transparency.
How do you produce a transparent icon with image magick (convert)?
I generate transparent PNGs with the -alpha transparent option. For example:
convert -size 100x100 -alpha transparent \
-stroke black -strokewidth 5 -fill blue \
-draw "rectangle 20,20,80,80" \
xc:#990000 test.png
This creates test.png with a floating blue box with a black border, inside an image with a transparent background. It uses a block colour as the "input" image , but the red is obliterated by the full transparency of its channel.
If you remove the alpha, you'll see the red source image.
Had the same problem when trying to generate a transparent favicon from transparent PNGs. Here's what worked for me:
convert transparent-img1.png transparent-img2.png transparent-img3.png -channel Alpha favicon.ico
Related
I have a small icon GIF that I would like to change the color. All opaque GIF pixels should be replaced by this new color, but preserve transparency for the gif. Then I need to place that new colored GIF over a background map, all in one command line. Here is what I have, but it's not changing all gif opaque pixels. Attached is the GIF icon. (Edit: I know im only targeting the white here, but just can't figure out how to target ALL opaque pixels in the GIF)
exec("{$convert} {$map_image} \( {$map_icon} -fill orange -opaque white -geometry +1700+600 \) -composite map2.jpg ");
Use +opaque none to fill all non-transparent colors in ImageMagick. The +opaque means everything "but" that color.
convert grid.gif -fill orange +opaque none x.png
I am trying to add a 10px red border to a transparent PNG using ImageMagick, while preserving any existing transparency that might exist within the image. Here is my source image:
If you download and view that image with an image viewer, you'll see that it has a transparent background.
According to everything I've read, the following Imagemagick command should add a 10px red border to the image:
convert input.png -bordercolor red -border 10 output.png
It actually does add the red border to the image, since the output dimensions are 20px larger in both directions. Unfortunately it also changes the background color of the image to red as well. Here is the output file:
I do not want the transparent area to be changed to red. I only want to add a red border around the transparent image.
I've tried using both ImageMagick version 6.9.10-23 (Ubuntu) and 7.1.0 (via CloudConvert API), with the same result. I've spent hours(!) trying to solve this.
What am I doing wrong?
I found the answer in this thread: https://legacy.imagemagick.org/discourse-server/viewtopic.php?t=31843 . Here are the two money quotes:
So, "-bordercolor red -border 2" should create an opaque red image 2
pixels larger than the input, and composite the input over this. As
your input is "-size 100x100 xc:none", the result should be 102x102
opaque red pixels. You might think this is "pretty obviously
incorrect", but it is the documented behaviour.
and
Nevertheless, you can get it to work to have the transparent inside,
if you add -compose copy before -bordercolor red -border 2 in both the
current IM 6 and IM 7. This just may have to be the way to do it from
here on, if there is a good reason for the changed behavior.
Here is the command that produces the result I am after:
convert -background transparent -bordercolor red -compose Copy -border 10 input.png output.png
Here's an answer that fully preserves the transparency
convert input.png +write mpr:INP -alpha extract -morphology dilate disk:10 \\( +clone -fill Black -colorize 100 \\) +swap -compose CopyOpacity -composite mpr:INP -compose Over -composite output.png
From https://legacy.imagemagick.org/Usage/crop/#extent
Here is a simple way to do that in Imagemagick. Change the compose setting from over to copy.
Input:
convert logo_transp.png -compose copy -bordercolor red -border 10 logo_transp_border.png
As the title suggests I have a PNG image that has some transparency. I'd like to fill that transparency with a second image (which is currently a JPEG, but it's not a problem to convert it to a PNG).
Every post I have found searching on the Internet was about the "inverse" problem (from an image with a background to an image with transparency), so obviously it did not work out for my situation; for example, I tried
convert -flatten myimg.png myimg.png
(taken from here) and
convert myimg1.png -transparent white myimg.png
(taken from here).
In ImageMagick 6, if the two images are the same size, then you can just flatten the transparent image over the background image.
Background (lena.jpg):
Transparent (logo_crop_trans.png):
convert lena.jpg logo_crop_trans.png -flatten lena_logo.jpg
If using ImageMagick 7, then change convert to magick.
If you want to anti-alias the transparent image so that it is not so jagged, then use some blur to smooth the outline (Unix syntax):
convert lena.jpg \( logo_crop_trans.png -channel a -blur 0x1 -level 50x100% +channel \) -compose over -composite lena_logo2.jpg
If on Windows remove the \ before the parentheses.
I have to create an image, which is an overlay texture made up of a white image with some transparency to give it the appearance of a rubber stamp.
For reference see the image "stamp_overlay.png" in the video http://railscasts.com/episodes/374-image-manipulation .
This is what i did:
convert -size 70x70 canvas:white stamp_overlay1.png
and then
convert stamp_overlay1.png -transparent white stamp_overlay1.png
But how do I make it like the image?
I am pretty much new to ImageMagick. Any help is highly solicited.
Updated Answer
Ok, I got that wrong! You want to create a stamp overlay, not overlay a stamp overlay. You can do that like this:
# Create white square, draw a black rectangle, then make black pixels transparent
convert -size 300x300 xc:white \
-fill black -draw "rectangle 20,100 200,280" \
-transparent black out.png
Original Answer
I find your question very hard to understand, but I think I know what you want. First, let's create a solid red image
convert -size 70x70 xc:red red.png
then let's composite the stamp_overlay.png image on top
convert red.png stamp_overlay.png -composite out.png
which gives this
but now you want to make the white areas transparent, so you need to do this:
convert red.png stamp_overlay.png -composite -transparent white out.png
and that still looks the same on this white background, but it isn't :-)
I want to add a tiled background to a transparent image.
According to the docs this should do it:
convert test.png -texture paper.png result.png
I also tried other variations (with -composite, -flatten, -tile, etc.) but result.png is either still transparent or just gets a white background.
ImageMagick-6.8.7-5 on Windows.
I got it to work with
convert -size 4096x4096 tile:paper.png test.png -flatten result.png