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• PC Video Conferencing in the Year 1999

  21 juin 2011, par Multimedia Mike — General

  Remember Intel’s custom flavor of H.263 cleverly named I.263 ? I think I have finally found an application that used it thanks to a recent thrift shop raid— Intel Video Phone :

  
  
  

  The root directory of the disc has 2 copies of an intro.avi video. One copy uses Intel Indeo 3 video and PCM audio. The other uses I.263 video and an undetermined (presumably Intel-proprietary) audio codec — RIFF id 0x0402 at a bitrate of 88 kbits/sec for stereo, 22 kHz audio. The latter video looks awful but is significantly smaller (like 4 MB vs. 25 MB).

  This is the disc marked as "Send it to a friend...". Here’s the way this concept was supposed to operate :

  • You buy an Intel Video Phone Camera Pack (forgotten page courtesy of the Internet Archive) which includes a camera and 2 CDs.
  • You install the camera and video phone software on your computer.
  • You send the other CD to the person whom you want to be able to see your face when you’re teleconferencing with them.
  • The other party installs the software.
  • The 2 of you may make an internet phone call presumably using commodity PC microphones for the voice component ; the person who doesn’t have a camera is able to see the person who does have a camera.
  • In a cunning viral/network marketing strategy, Intel encourages the other party to buy the physical hardware as well so that they may broadcast their own visage back to the other person.

  If you need further explanation, the intro lady does a great job :

  
  
  

  I suspect I.263 was the video codec driving this since Indeo 3 would probably be inappropriate for real time video applications due to its vector quantizing algorithm.

• ffmpeg watermarking processing is very slow

  25 février 2014, par Hitesh Rohilla

  I am working on a video processing project and using ffmpeg for watermarking. I achieve exactly what i want but the problem is that the process is very very slow.

  I am using a Intel Smart 2nd gen family Core-i5 Processor with 4GB RAM on a 32 bit operating system Microsoft Windows-8 on a 64-bit CPU.

  I tried watermarking a video [mp4] of length 1:30 Min. size of file is 1.5GB

  Whole process accomplish in 3 Hrs to watermark my video file and what i noticed while process is that ffmpeg was processing 28 frames per sec first and then later it slow down up to 20 frames per second. a normal human watch video with frame rate of 30 frame per second and process was even slower then this that's why it took more time [3 Hrs] then the actual length of video itself [1:33]

  What i think to make process efficient is to use ffmpeg Watermarking Source Code and modify it somewhat...

  I want to ask if someone have achieve fast watermarking before by any other way or have modified this code to achieve faster process in order to save my time...

• avfilter/vf_libplacebo : correctly update SAR to reflect scaled result

  16 juin, par Niklas Haas

  avfilter/vf_libplacebo : correctly update SAR to reflect scaled result
  This aligns the behavior of vf_libplacebo with other filters in the
  
  vf_scale family, that forward any change in the SAR as a result of
  
  changing the output resolution to the output frame / link, and updates
  
  the ff_scale_adjust_dimensions() call to continue working as intended.
  The new behavior reflects the documentation of vf_libplacebo, which
  
  described this behavior despite that not being the way the filter worked
  
  up to this point.
  As an aside, also fixes a bug where the AVFrame SAR was inconsistent
  
  with the AVFilterLink SAR when the s->nb_inputs > 1 condition was met.
  

  • [DH] libavfilter/vf_libplacebo.c