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• Google’s YouTube Uses FFmpeg

  9 février 2011, par Multimedia Mike — General

  Controversy arose last week when Google accused Microsoft of stealing search engine results for their Bing search engine. It was a pretty novel sting operation and Google did a good job of visually illustrating their side of the story on their official blog.

  This reminds me of the fact that Google’s YouTube video hosting site uses FFmpeg for converting videos. Not that this is in the same league as the search engine shenanigans (it’s perfectly legit to use FFmpeg in this capacity, but to my knowledge, Google/YouTube has never confirmed FFmpeg usage), but I thought I would revisit this item and illustrate it with screenshots. This is not new information— I first empirically tested this fact 4 years ago. However, a lot of people wonder how exactly I can identify FFmpeg on the backend when I claim that I’ve written code that helps power YouTube.

  Short Answer
  How do I know YouTube uses FFmpeg to convert multimedia ? Because :

  1. FFmpeg can decode a number of impossibly obscure multimedia formats using code I wrote
  2. YouTube can transcode many of the same formats
  3. I screwed up when I wrote the code to support some of these weird formats
  4. My mistakes are still present when YouTube transcodes certain fringe formats

  Longer Answer (With Pictures !)
  Let’s take a video format named RoQ, developed by noted game designer Graeme Devine. Originated for use in the FMV-heavy game The 11th Hour, the format eventually found its way into the Quake 3 engine as well as many games derived from the same technology.

  Dr. Tim Ferguson reverse engineered the format (though it would later be open sourced along with the rest of the Q3 engine). I wrote a RoQ playback system for FFmpeg, and I messed up in doing so. I believe my coding error helps demonstrate the case I’m trying to make here.

  Observe what happened when I pushed the jk02.roq sample through YouTube in my original experiment 4 years ago :

  
  
  

  Do you see how the canyon walls bleed into the sky ? That’s not supposed to happen. FFmpeg doesn’t do that anymore but I was able to go back into the source code history to find when it did do that :

  
  
  

  Academic Answer
  FFmpeg fixed this bug in June of 2007 (thanks to Eric Lasota). The problem had to do with premature colorspace conversion in my original decoder.

  Leftovers
  I tried uploading the video again to see if the problem persists in YouTube’s transcoder. First bit of trivia : YouTube detects when you have uploaded the same video twice and rejects the subsequent attempts. So I created a double concatenation of the video and uploaded it. The problem is gone, illustrating that the backend is actually using a newer version of FFmpeg. This surprises me for somewhat esoteric reasons.

  Here’s another interesting bit of trivia for those who don’t do a lot of YouTube uploading— YouTube reports format details when you upload a video :

  
  
  

  So, yep, RoQ format. And you can wager that this will prompt me to go back through the litany of unusual formats that FFmpeg supports to see how YouTube responds.

• 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 Re-muxing .MKV to MP4\MV4 while retaining Dolby Digital Plus JOC [closed]

  31 décembre 2020, par David F

  My ask is, does anyone have any knowledge of how to remux and keep Enhanced AC-3 with Joint Object Control with FFMPEG.

  


  I would be grateful if anyone could help me out here. I'm remuxing a number of video files from .MKV to .MP4\M4V so they play on the Apple platform (including the TV App). It's important NOT to convert, but to remux.

  


  I have achieved the ability to remux 4K HDR with Dolby Digital Plus in a .MKV to 4K HDR with Dolby Digtial 5.1. MP4. The issue is retaining the Dolby Digital Plus. This contains the ATMOS information for object based sound.

  


  The media players on Apple reports Dolby Digital Plus for the .MKV and Dolby Digital 5.1 for .MP4. I know Dolby Labs to allow free remuxing of Dolby Digital Plus/ Atmos with sample code and information they have uploaded onto Github for developers.

  


  I'm using FFMPEG with the following command :-

  


  ffmpeg -i original.mkv -c:v copy -c:a eac3 -tag:v hvc1 output.mp4

  


  Resulting output from MediaInfo (note .MKV contains only 1 video and 1 audio track)

  


  Audio -----Original.mkv

  


  

  • ID : 2

  


  • Format : E-AC-3 JOC

  


  • Format/Info : Enhanced AC-3 with Joint
Object Coding

  


  • Commercial name : Dolby Digital Plus with Dolby
Atmos

  


  • Codec ID : **A_**EAC3

  


  • Duration : 51 min 51 s

  


  • Bit rate mode : Constant

  


  


  Audio ----- Remuxed.mp4

  


  

  • ID : 2

  


  • Format : E-AC-3

  


  • Format/Info : Enhanced AC-3

  


  • Commercial name : Dolby Digital Plus

  


  • Codec ID : ec-3

  


  • Duration : 51 min 51 s

  


  • Bit rate mode : Constant

  


  


  The remux operation finished in about 1 minute for a 8Gb 4k video file, so I know there is no reencoding.

  


  I can see that .mp4 can take E-AC-3 Joint Object Control (JOC) with the demo files from Dolby labs.

  


  I've also remuxed an MKV to MKV and able to see the same result. The JOC markings have been removed with FFMPEG

  


  Thanks in advanced.

  


  David