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• Recommendataions for robust and invisible video watermarking software / library [on hold]

  1er mars 2014, par id128

  I am doing a research project in search of a robust and invisible video watermarking software / library (preferably in C++). It needs to meet the following requirements :

  • Robust - that is the watermark needs to survive common transformations such as re-encoding, A/D / D/A conversion, luminance/color change, shift, and crop (both in size and length)'

  • Invisible - to the human eye

  The watermark does not need to carry too much data - maybe a 64-bit UUID - and can be temporal or spatial. But I will need the ability to determine the existence (or not) of the watermark with only a few seconds of the video

  Some research I have done so far :

  • JAWS research paper (http://pdf.aminer.org/000/316/002/the_viva_project_digital_watermarking_for_broadcast_monitoring.pdf) but cannot find any implementations on the web and the authors are not responding to emails. Plus, that research is over 10 years old and I am hoping for something more modern.

  • OpenPuff - does not satisfy the robustness requirement in that the resulting video does not survive transformations.

  • ffmpeg software - I have figured out how to overlay a visible watermark, but that does not satisfy the invisibility requirement.

  Any ideas / suggestions / pointers will be awesome. Thanks.

• Storing high quality video stream (from IP Action Camera) continuously to a Storage Device and issues around Write-Speed bottlenecks

  21 mai 2017, par Aldo

  I am looking to get an Action Camera (Eken H8R, or a GoPro) for a project. Let me explain the scenario I have :

  I will obtain a live stream from the camera on to a Raspberry Pi (over WiFi) as shown here. Next, I want to continuously segment this live stream into 10-15 minute video clips and store them in an external Hard Drive (which is connected to the RPi). I am considering this thread, and the avconvcommand mentioned in the answer by Alexander.

  Now, my concern is write-speed limitations. The video stream would probably have a high bitrate, and might be 4k30fps, in which case file sizes would be huge. Would write speed to disk be a bottleneck ? If so, how will the Pi maintain a buffer to achieve this ? Could I run out of space as the memory stick on the Pi would only be around 8 gigs ? If so, what’s a better alternative ? Please correct me if I’m wrong on these as I’m only a beginner.

• Storing high quality video stream (from IP Action Camera) continuously to a Storage Device and issues around Write-Speed bottlenecks

  21 mai 2017, par Aldo

  I am looking to get an Action Camera (Eken H8R, or a GoPro) for a project. Let me explain the scenario I have :

  I will obtain a live stream from the camera on to a Raspberry Pi (over WiFi) as shown here. Next, I want to continuously segment this live stream into 10-15 minute video clips and store them in an external Hard Drive (which is connected to the RPi). I am considering this thread, and the avconvcommand mentioned in the answer by Alexander.

  Now, my concern is write-speed limitations. The video stream would probably have a high bitrate, and might be 4k30fps, in which case file sizes would be huge. Would write speed to disk be a bottleneck ? If so, how will the Pi maintain a buffer to achieve this ? Could I run out of space as the memory stick on the Pi would only be around 8 gigs ? If so, what’s a better alternative ? Please correct me if I’m wrong on these as I’m only a beginner.