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• Embedding SMPTE timecode into mpeg1/2 video (no audio)

  6 janvier 2014, par user3164141

  I am working on a task which a client requires smpte drop frame timecode to be embedded into an mpeg1/2 video that my software will capture and encode. I have had success with encoding using both openCV and ffmpeg (windows). What I am having trouble with is embedding timecode.

  I've spent about a month researching this and have not been able to come up with a solution.
  Is there software available that can do what I need ?

  In my head, I picture a video file without timecode and I open with a player. It displays time in hh:mm:ss:ms. Then I imagine a video with timecode would display time information as hh:mm:ss:ff. This is not the case. Many video players don't even support displaying timecode.

  How is timecode stored in mpeg1/2 files ? I had thought it was stored on a per frame basis and would be as simple as :

  frameToEncode->setTimecode(SMPTE_DROPFRAME, framenum);
  
  MPEGEncoder::encodeFrame(frameToEncode);

  I have scoured the internet for an answer to this. Maybe I'm searching with the wrong terms, but I cannot find a clear cut solution to simply embed timecode to my video file.

  I have tried to use ffmpeg for this but have not been able to confirm/deny my attempts. Is there software I can use that will tell me I have embedded timecode in my video file ? I have tried using adobe premiere pro and roxio creator pro with no success.

  Lastly, is what my client asking even possible ? Is it possible to embed timecode. I am stunned by the lack of information I have been able to find on this and am beginning to think what is required isn't even possible. If it is possible, is there a commercial or free sdk/library capable of this ?

  TL ;DR : I need to embed timecode into an mpeg1/2 video file which I am capturing and encoding on the fly. How is timecode stored in mpeg1/2 files ? As a global header ? Per frame ? Something else ? I need software that can verify embedded timecode exists. Is what the client asking even possible ? If so, is there a commercial or free SDK available that can accomplish my task ?

  Note : I would need a c/c++ library capable of embedding the timecode.

• Find out what people are searching when coming from search engines

  7 novembre 2017, par InnoCraft — Plugins

  At InnoCraft, we know that SEO is an important topic for most of you. If you have not heard of this term before, SEO stands for Search Engine Optimization. It consists in having your content website visible within the search result pages without paying for ads. SEO is also often referred as “natural” or “organic” traffic.

  In SEO, one of the most valuable data to analyze is the keyword used by the visitor to come to your website. Since 2011, major search engines decided to not disclose this data anymore, that’s the reason why you are seeing the “Keyword not defined” data within some of your Piwik reports, also called “not provided” :

  

  Keyword not defined in Piwik

  The solution

  As your keyword data is collected by search engines, each of them provides the searched keywords within different services such as :

  • Google Search Console
  • Bing/Yahoo Webmaster tools
  • Yandex Webmaster

  Those services allow website owners to see how many times their website appeared within the SERP (Search Engine Results Page), how bots are crawling your pages, which search terms they used, and more. The drawback is, that they make take this data available only for a short period, you need to log in to all these services to get the insights you need and you cannot get aggregated overall keyword reports (over all search engines combined).

  The solution that gives you all this data in Piwik

  Would you like to know what the not defined search keywords in Piwik really are ? Would you like to combine keywords data from major search engines in one place ? Would you like to know how important your website is according to Google and Microsoft Bing and Yahoo ?

  At InnoCraft, the company behind Piwik, we created a plugin called “Search Engine Performance Keywords”. With this plugin, you will :

  1. be able to keep the search terms forever
  2. save time by crossing data from Google and Bing search within Piwik
  3. get an overview of how Google and Bing are crawling your site
  4. monitor search rankings and click-through rates for each keyword

  1 – Data ownership & data retention

  Once more, it is going back to Piwik roots. As Piwik is a Free software, you own the data you collect. Once the import is successful, you will be able to keep the keywords data as long as you wish. In the case of services such as Google Search Console, they will delete the data after 90 days !! Without our plugin you will not be able to analyze precisely how your SEO is doing month by month, year by year.

  2 – Save time by using a single interface

  Google and Bing have no interest in gathering data coming from various search engines… we do. As a result, with our plugin you can visualize the data coming from those two sources within a single report in order to analyze your SEO in a better way.
  You will not have to use spreadsheets anymore and no chance to miss some important keywords which you would maybe miss when you don’t aggregate them in a single report.

  

  3 – Crawl overview check

  Both Google and Bing have a crawl “budget”. This budget needs to be optimized in order for search engine bots to consider the most relevant pages. By gathering all the data within Piwik you will have a clear view of how well your website is appreciated by search engines :

  

  4 – Monitor search rankings

  The Search Engine Keywords Performance feature allows you to monitor search rankings for a given keyword and see his evolution :

  

  it also gives you the possibility to compare the performances of several keywords in order to see how your website is performing as a whole :

  

  How to get started ?

  The “Search Engine Keywords Performance” plugin has been developed by the InnoCraft team as a premium feature.

  Get Search Engine Keywords Performance on the Marketplace

  If you are not sure, note that InnoCraft is offering an unconditional and hassle-free 30-day money back guarantee period.

  Once you have installed the plugin, follow the guide in order to have it up and running.
  The installation process is not difficult in itself but takes some time as it requires to access to Google and Bing APIs.

  If you enjoyed this article, you may appreciate the following one about how to integrate ad services to Piwik : Make better online marketing decisions with the AOM plugin.

• ffmpeg FPS information mismatch with the video

  8 décembre 2017, par Adorn

  I have a bunch of videos with some statistics of what is happening inside a video. One such piece of information is given in terms of time of the video in seconds up to one decimal point.

  To get the FPS of a video, I am using ffmpeg -i

  But when I manually compute one particular frame’s time using given FPS, it does not match.

  For example, ffmpeg outputs FPS = 30.

  I look at the video statistics, the frame at the 156.8 = 2.368 has to be
  4704'th frame. I open the video using ’skvideo’, read all the frames, and view the 4704'th frame. It is some frame around time 2.12 ?. I checked multiple such instances in multiple videos and this is a common behavior.

  I do not understand why this is so and how can I get around the problem ?

  As such I am not bounded by ffmpeg. Skvideo is being used to read the videos. I tried opencv, as of now it does not work with VideoCapture, and reinstalling it is costly for me time wise. But I guess ’opencv/skvideo’ should not matter, one can count the frames manually as well.

  So, in the solution, I am looking out for -

  1. Given timestamps of inside of a video, how can I find a frame of that particular time location ?

  2. In case someone might have already worked on this, this is related to THUMOS dataset. I am on Ubuntu 16.04

  EDIT_1

  Actually I can be more specific as it is a publicly available data. The time bounds are of an important activity. For example, in a video, when does basketball dunk occurs ? It is given in pairs - [start end]. Some videos have multiple activities, some have only one.

  Here is a sample video, and following are the activity times.

  [[  16.5, 20.8],
  
  [  26.6, 32.2],
  
  [  34.8, 42.1],
  
  [  47.8, 50.0],
  
  [  58.1, 62.9],
  
  [  65.6, 67.2],
  
  [  68.5, 74.0],
  
  [  76.4, 78.3],
  
  [  78.7, 79.8],
  
  [  80.8, 82.1],
  
  [  85.0, 87.3],
  
  [  90.1, 91.4],
  
  [  98.5, 100.3]]

  I also tried checking manually, 32.87 FPS "almost" works for few videos but not for all. and almost means it is off by 10 frames. This is a huge difference for my task, and I need exact frame.

  Also, there has to be some way, because it can be visually observed with multiple video players that times in the dataset are correct.