Collaborate Disseminate
I know water mark the photograph is one method to protect ones copyright over the picture. is there any other technique through which one can prevent or detect the plagiarism of photos.
Continue reading What is the mechanism to protect photos uploaded on social media?
Public key watermarking uses a private key to embed the watermark and a corrosponding public key to detect.
Is it possible to detect a watermark from only a small chunk of the file? Does it matter which part? How big must th… Continue reading Public key (asymmetric) watermarking: detect from small chunk of file?
Is there a watermarking scheme for images and audio that is:
Invisible – should be imperceptible for a human.
Non-invertable – cannot be removed by any means without the original.
Robust – in order to destroy the watermark you have to sp… Continue reading Invisible, Non-invertable, public, robust, replicated watermarking scheme?
Sometimes I buy in a online shop video files (mp4). The online shop forces it’s customers to buy with verified real name. In case of leaking his content the shop can identity who leaked it. I don’t know how he does it technically, I guess some sort of Digital watermarking.
Now I compared the SHA Checksum of a video I bought and one leaked on a forum. The same checksum.
shasum customer_a.mp4 customer_b.mp4
195bb682e5cb4fzod75923321d0e9c82316b6952 customer_a.mp4
195bb682e5cb4fzod75923321d0e9c82316b6952 customer_b.mp4
file customer_a.mp4
customer_a.mp4: ISO Media, Apple iTunes Video (.M4V) Video
mediainfo customer_a.mp4
General
Complete name : customer_a.mp4
Format : MPEG-4
Codec ID : M4V (M4V /mp42/isom)
File size : 907 MiB
Duration : 21 min 14 s
Overall bit rate mode : Variable
Overall bit rate : 4 193 kb/s
Encoded date : UTC 2017-07-31 14:29:26
Tagged date : UTC 2017-07-31 14:29:26
©TIM : 00:00:00:00
©TSC : 25
©TSZ : 1
Video
ID : 1
Format : AVC
Format/Info : Advanced Video Codec
Format profile : Main@L3.2
Format settings, CABAC : No
Format settings, RefFrames : 2 frames
Format settings, GOP : M=1, N=33
Codec ID : avc1
Codec ID/Info : Advanced Video Coding
Duration : 21 min 14 s
Bit rate : 3 995 kb/s
Width : 1 280 pixels
Height : 720 pixels
Display aspect ratio : 16:9
Frame rate mode : Constant
Frame rate : 25.000 FPS
Standard : PAL
Color space : YUV
Chroma subsampling : 4:2:0
Bit depth : 8 bits
Scan type : Progressive
Bits/(Pixel*Frame) : 0.173
Stream size : 865 MiB (95%)
Language : English
Encoded date : UTC 2017-07-31 14:49:20
Tagged date : UTC 2017-07-31 14:49:20
Color range : Limited
Audio
ID : 2
Format : AAC
Format/Info : Advanced Audio Codec
Format profile : LC
Codec ID : 40
Duration : 21 min 14 s
Source duration : 21 min 14 s
Bit rate mode : Variable
Bit rate : 192 kb/s
Maximum bit rate : 245 kb/s
Channel(s) : 2 channels
Channel positions : Front: L R
Sampling rate : 48.0 kHz
Frame rate : 46.875 FPS (1024 SPF)
Compression mode : Lossy
Stream size : 41.0 MiB (5%)
Source stream size : 41.0 MiB (5%)
Language : English
Encoded date : UTC 2017-07-31 14:49:20
Tagged date : UTC 2017-07-31 14:49:20
Does this mean if I share this video he can’t trace me back? Are there other methods I am unaware?
I am interested in watermarking a video for copyright purposes. The requirements are as follows:
The watermark must be barely noticeable to the naked eye.
The watermark must be able to be extracted from a device such as a smartphone came… Continue reading Is it possible to embed information that is both nearly invisible to the naked eye and decodable from an external camera?
I’m trying to embed a secret watermark in a website so that I can link any screenshots to the user who created them. The page looks something like this:
It has a custom background (user can change it by providing a link) o… Continue reading Hidden digital watermark in a website which can survive .jpg screenshots?