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• Trolls in trouble

  6 juin 2013, par Mans — Law and liberty

  Life as a patent troll is hopefully set to get more difficult. In a memo describing patent trolls as a “drain on the American economy,” the White House this week outlined a number of steps it is taking to stem this evil tide. Chiming in, the Chief Judge of the Court of Appeals for the Federal Circuit (where patent cases are heard) in a New York Times op-ed laments the toll patent trolling is taking on the industry, and urges judges to use powers already at their disposal to make the practice less attractive. However, while certainly a step in the right direction, these measures all fail to address the more fundamental properties of the patent system allowing trolls to exist in the first place.

  System and method for patent trolling

  Most patent trolling operations comprise the same basic elements :

  1. One or more patents with broad claims.
  2. The patents of (1) acquired by an otherwise non-practising entity (troll).
  3. The entity of (2) filing numerous lawsuits alleging infringement of the patents of (1).
  4. The lawsuits of (3) targeting end users or retailers.
  5. The lawsuits of (3) listing as plaintiffs difficult to trace shell companies.

  The recent legislative actions all take aim at the latter entries in this list. In so doing, they will no doubt cripple the trolls, but the trolls will remain alive, ready to resume their wicked ways once a new loophole is found in the system.

  To kill a patent troll

  As Judge Rader and his co-authors point out in the New York Times, “the problem stems largely from the fact that, [...] trolls have an important strategic advantage over their adversaries : they don’t make anything.” This is the heart of the troll, and this is where the blow should be struck. Our weapon shall be the mightiest judicial sword of all, the Constitution.

  The United States Constitution contains (in Article I, Section 8) the foundation for the patent system (emphasis mine) :

  The Congress shall have Power [...] To promote the Progress of Science and useful Arts, by securing for limited Times to Authors and Inventors the exclusive Right to their respective Writings and Discoveries.

  Patent trolls are typically not inventors. They are merely hoarders of other people’s discarded inventions, and that allowing others to reap the benefits of an inventor’s work would somehow promote progress should be a tough argument. Indeed, it is the dissociation between investment and reward which has allowed the patent trolls to rise and prosper.

  In light of the above, the solution to the troll menace is actually strikingly simple : make patents non-transferable.

  Having the inventor retain the rights to his or her inventions (works for hire still being recognised), would render the establishment of non-practising entities, which most trolls are, virtually impossible. The original purpose of patents, to protect the investment of inventors, would remain unaffected, if not strengthened, by such a change.

  Links

  • Taking on Patent Trolls to Protect American Innovation
  • Fact Sheet : White House Task Force on High-Tech Patent Issues
  • Make Patent Trolls Pay in Court
  • Constitution of the United States

• C++ Extracting a h264 Subsequence from Byte Stream

  10 janvier 2017, par Simon

  I have a raw h.264 byte stream coming from an RTSP network camera. In order to get the byte stream, I catch the piped output from ffmpeg using popen() :

  ffmpeg -i rtsp://address -c:v copy -an -c:v copy -an -f h264 pipe:1

  At some point in time, I would like to start recording from the stream for a while (and save everything to an mp4 file). I want to achieve this without decoding the stream to an intermediate format (e.g., yuv420p) and encoding it back. As a first test, I just started writing the output buffer to disk after a couple of seconds. Then, I can encode the video again using

  ffmpeg -i cam.h264 -c:v h264 -an -f copy cam_out.mp4

  Here, ffmpeg complains that the first part of the data is corrupted (it still seems to be able to recover from this as it just throws away the corrupted parts). This of course makes sense as I simply start recording without looking for the start of frames etc.. Ideally, I would like to start and stop recording at the correct parts of the stream. I had a small glimpse on the h.264 format and the NAL units. Is there some simple way of detecting "good" positions in the stream to start recording ?

• avformat/hlsenc : Avoid duplicating strings when parsing

  25 mai 2020, par Andreas Rheinhardt

  avformat/hlsenc : Avoid duplicating strings when parsing
  Up until now, the HLS muxer uses av_strtok() to split an input string
  
  controlling parameters of the VariantStreams and then duplicates
  
  parts of this string containing parameters such as the language or the
  
  name of the VariantStream. But these parts are proper zero-terminated
  
  strings of their own that are never modified lateron, so one can simply
  
  use the substring as-is without creating a copy. This commit implements
  
  this.
  The same also happened for the string controlling the closed caption
  
  groups.
  Furthermore, add const to indicate that the pointers to these substrings
  
  are not used to modify them and also to indicate that these strings are
  
  not allocated on their own.
  Signed-off-by : Andreas Rheinhardt <andreas.rheinhardt@gmail.com>
  

  • [DH] libavformat/hlsenc.c