Stack Overflow
Stack Overflow

Questions tagged [watermark]

A watermark is information embedded within a file. In the most common usage, watermarks are added to images to identify the image's creator.

Digital watermarks may be used to verify the authenticity or integrity of the carrier signal or to show the identity of its owners. It is prominently used for tracing copyright infringements and for banknote authentication.

Like traditional watermarks, digital watermarks are only perceptible under certain conditions, i.e. after using some algorithm, and imperceptible anytime else.

In contrast to a , watermarks can typically easily be added by a third party. A watermark can be forged, but should typically be hard to remove.

1196 questions
5
votes
2 answers

ImageMagick composite resizes image before composing

I'm using ImageMagick's composite command to compose one smaller image over larger one. The resulting image should be of size of the background image (the larger one). Additionally I want the smaller one to be always of the same size. Currently I…
Lukasz Korzybski
  • 6,689
  • 2
  • 27
  • 27
5
votes
6 answers

ASP.NET: Adding 'Watermark' to images on the fly

I have seen great questions and answers regarding adding watermark on images with php I would like to do the same, this time with ASP.NET So here are a couple of questions. How can i do that with ASP? Is this process going to be a great overload…
OrElse
  • 9,709
  • 39
  • 140
  • 253
5
votes
2 answers

Html placeholder text in a textarea form

On one of my websites I have created a form that collects the persons name, email and a description of their idea. I limited the characters of the description to 500 characters as I don't want to read a ton and I figured out how to have the text…
GFlam
  • 1,109
  • 4
  • 25
  • 38
5
votes
3 answers

How to create a textbox watermark?

I wish to create a textbox watermark without using either Ajax or JavaScript. How can I do this?
the_dopamine
  • 899
  • 6
  • 12
  • 21
5
votes
1 answer

iText 7 - Add and Remove Watermark on a PDF

I would like to add and remove a watermark to a PDF using iText 7. I was able to add the watermark, but unable to remove it again. I could only find relevant code/examples related to iText 5. Any pointers appreciated, thanks. This is how I added the…
Ivan
  • 368
  • 3
  • 14
5
votes
1 answer

How to put watermark using Bootstrap

I am a newbie to bootstrap world. Is there a way to put watermark using Bootstrap ? If there is please help me out with a sample code: Watermark sample code
Soumyaranjan Rath
  • 57
  • 1
  • 1
  • 3
5
votes
1 answer

Add watermark to image

I'm trying to add watermark to an image on my website. The way I want it to work is to show the watermark when the image is downloaded or shown on other websites. On my website I want to show it without the watermark. It would be awesome if the…
Fubundzer
  • 75
  • 2
  • 9
5
votes
4 answers

Watermark using pdfmake

In Javascript, I am using pdfmake to generate a pdf document. I read it from github that it supports watermark and the following is my usage but it is giving me some random and weird characters. Those characters are the same no matter what texts are…
david park
  • 139
  • 2
  • 11
5
votes
1 answer

what's the best practice for image steganography resistant to various attacks?

I'm really curious about that because nowadays every channel could modify or compress images some way which could be considered as a attack on steganography. We can divide steganography to two basic types, first operates on spatial domain of image…
user1563721
  • 1,373
  • 3
  • 28
  • 46
5
votes
4 answers

ffmpeg watermark without vhook?

Since the vhook subsystem has been removed from the latest version of FFMPEG, how can I add a watermark to a video? I need to be able to overlay a PNG with background transparency.
Felix Geisendörfer
  • 2,902
  • 5
  • 27
  • 36
5
votes
1 answer

Adding watermarks to mp3 downloads

I noticed that companies such as iTunes and Amazon add "watermarks" to their mp3 files showing information such as the following: From where the file was purchased. Who purchased it. etc. Amazon also states that "Some record companies require us…
Curious Coder
  • 177
  • 1
  • 11
5
votes
2 answers

add watermark small image to large image opencv4android

I've been trying to add an image to large image at desired position. I found a way to add watermark in opencv by doing addWeighted(src, alpha, water,--,dst,--), but the problem is that both watermark and surface image should be of same sizes which I…
Khawar
  • 859
  • 11
  • 30
5
votes
1 answer

Adding a dynamically positioned watermark to a video via ffmpeg

I'm trying to add a watermark to a video by using ffmpeg. But there is one requiment which makes that very difficult to me to understand how to make it, I searched over the web of cource. So, I need the watermark being change its position every 20…
Lena Borieva
  • 51
  • 1
  • 2
5
votes
1 answer

PHP - Watermark PNG Transparency/Alpha

I know this has been covered PLENTY of times but I keep trying different scripts and modifying the one I have, and I still can't get my PNG-24 watermark.png to be transparent over the top of my parent image. This is what I have…
TheCarver
  • 19,391
  • 25
  • 99
  • 149
5
votes
2 answers

text input watermark using custom bindingHandler

I've been trying to create a custom bindingHandler that i can use to give a watermark behaviour to text input fields. By watermark i mean: to add default values to text fields that are removed on focus, and replaced on blur if the text field is…
Robbie
  • 18,750
  • 4
  • 41
  • 45
1 2 3
…
79 80