Recherche avancée

Sur d’autres sites (3162)

• FFmpeg transcoding video H.264 -> AV1 leads to distorted image

  21 juin 2023, par user1584149

  I'm reading video from stdin via pipe similar to this one Python gets stuck at pipe.stdin.write(image.tostring())

  


  FFmpeg is using libsvtav1 codec with options according to documentation

  


  ffmpeg -y -f rawvideo -i pipe:0 -s {frame_width}x{frame_height} -r {frame_rate} -c:a copy -c:v libsvtav1 -preset 6 -crf 30 -svtav1-params "color-format=1:film-grain-denoise=0:mbr=2M" {output_file} 


  


  Here's couple of details about used FFmpeg version as well as input video

  


  ffmpeg version n5.1.3-14-ge5b5dd6653-20230621 Copyright (c) 2000-2022 the FFmpeg developers
  built with gcc 13.1.0 (crosstool-NG 1.25.0.196_227d99d)
  configuration: --prefix=/ffbuild/prefix --pkg-config-flags=--static --pkg-config=pkg-config --cross-prefix=x86_64-ffbuild-linux-gnu- --arch=x86_64 --target-os=linux --enable-gpl --enable-version3 --disable-debug --enable-iconv --enable-libxml2 --enable-zlib --enable-libfreetype --enable-libfribidi --enable-gmp --enable-openssl --enable-lzma --enable-fontconfig --enable-libvorbis --enable-opencl --enable-libpulse --enable-libvmaf --enable-libxcb --enable-xlib --enable-amf --enable-libaom --enable-libaribb24 --enable-avisynth --disable-chromaprint --enable-libdav1d --enable-libdavs2 --disable-libfdk-aac --enable-ffnvcodec --enable-cuda-llvm --enable-frei0r --enable-libgme --enable-libkvazaar --enable-libass --enable-libbluray --enable-libjxl --enable-libmp3lame --enable-libopus --enable-librist --enable-libssh --enable-libtheora --enable-libvpx --enable-libwebp --enable-lv2 --disable-openal --enable-libopencore-amrnb --enable-libopencore-amrwb --enable-libopenh264 --enable-libopenjpeg --enable-libopenmpt --enable-librav1e --enable-librubberband --disable-schannel --enable-sdl2 --enable-libsoxr --enable-libsrt --enable-libsvtav1 --enable-libtwolame --enable-libuavs3d --enable-libdrm --enable-vaapi --enable-libvidstab --enable-vulkan --enable-libshaderc --disable-libplacebo --enable-libx264 --enable-libx265 --enable-libxavs2 --enable-libxvid --enable-libzimg --enable-libzvbi --extra-cflags=-DLIBTWOLAME_STATIC --extra-cxxflags= --extra-ldflags=-pthread --extra-ldexeflags=-pie --extra-libs='-ldl -lgomp' --extra-version=20230621
  libavutil      57. 28.100 / 57. 28.100
  libavcodec     59. 37.100 / 59. 37.100
  libavformat    59. 27.100 / 59. 27.100
  libavdevice    59.  7.100 / 59.  7.100
  libavfilter     8. 44.100 /  8. 44.100
  libswscale      6.  7.100 /  6.  7.100
  libswresample   4.  7.100 /  4.  7.100
  libpostproc    56.  6.100 / 56.  6.100
Input #0, rawvideo, from 'pipe:0':
  Duration: N/A, start: 0.000000, bitrate: 331776 kb/s
  Stream #0:0: Video: rawvideo (I420 / 0x30323449), yuv420p, 1280x720, 331776 kb/s, 30 tbr, 30 tbn
Stream mapping:
  Stream #0:0 -> #0:0 (rawvideo (native) -> av1 (libsvtav1))
Svt[info]: -------------------------------------------
Svt[info]: SVT [version]:   SVT-AV1 Encoder Lib v1.5.0-12-g0f8b3a81
Svt[info]: SVT [build]  :   GCC 13.1.0   64 bit
Svt[info]: LIB Build date: Jun 20 2023 23:48:14
Svt[info]: -------------------------------------------


  


  The output video transcoded by SVT-AV1 codec is blemished as you can see on the images below. Normally I would say it could be caused by wrong pixel format, but input stream has yuv420 format what is the same as encoder's pixel format parameter —color-format.

  


  Please share your experience or ideas how to get it transcoding correctly.

  


  Thanks in advance.

  


  


  


• Cloaked Archive Wiki

  16 mai 2011, par Multimedia Mike — General

  Google’s Chrome browser has made me phenomenally lazy. I don’t even attempt to type proper, complete URLs into the address bar anymore. I just type something vaguely related to the address and let the search engine take over. I saw something weird when I used this method to visit Archive Team’s site :

  
  
  

  There’s greater detail when you elect to view more results from the site :

  
  
  

  As the administrator of a MediaWiki installation like the one that archiveteam.org runs on, I was a little worried that they might have a spam problem. However, clicking through to any of those out-of-place pages does not indicate anything related to pharmaceuticals. Viewing source also reveals nothing amiss.

  I quickly deduced that this is a textbook example of website cloaking. This is when a website reports different content to a search engine than it reports to normal web browsers (humans, presumably). General pseudocode :

  PLAIN TEXT

  C :

  1. if (web_request.user_agent_string == CRAWLER_USER_AGENT)
  2.  return cloaked_data ;
  3. else
  4.  return real_data ;

  You can verify this for yourself using the wget command line utility :

  <br />
$ wget --quiet --user-agent="<strong>Mozilla/5.0</strong>" \<br />
 http://www.archiveteam.org/index.php?title=Geocities -O - | grep \&lt;title\&gt;<br />
&lt;title&gt;GeoCities - Archiveteam&lt;/title&gt;

  $ wget —quiet —user-agent="Googlebot/2.1"
  http://www.archiveteam.org/index.php?title=Geocities -O - | grep \<title\>
  <title>Cheap xanax | Online Drug Store, Big Discounts</title>
  

  I guess the little web prank worked because the phaux-pharma stuff got indexed. It makes we wonder if there’s a MediaWiki plugin that does this automatically.

  For extra fun, here’s a site called the CloakingDetector which purports to be able to detect whether a page employs cloaking. This is just one humble observer’s opinion, but I don’t think the site works too well :
  
  

  
  
  

• How to track Google AdWords campaigns with Piwik

  19 décembre 2017, par InnoCraft

  In 2016, Google AdWords was the most popular ad service on earth. As a result, it may be your first source for ad spending. Are you interested in knowing whether you are making a profit out of it ? Would you like to know how to track users coming from AdWords with Piwik efficiently ? This is what this article is about.

  

  What you need to know about Google AdWords

  By default, each ad you create in Google AdWords is not tracked. Even worse than that, every click on your ad is identified in Piwik as an organic result coming from Google with the following value : “Keyword not defined”.

  To make it simple, if you do not track your AdWords campaigns both your paid and organic traffic will be biased within your Piwik account. It will be impossible for you to measure your return on investment and it means that you are throwing your money down the drain.

  In order to avoid this, we will show you how to track Google AdWords traffic into Piwik.

  How to track paid Google AdWords campaigns into Piwik

  If you want to analyze Google AdWords campaigns within Piwik properly, you need to add additional tracking parameters to the final URL of each of your ads.

  We recommend using the following tool to add the needed additional tracking parameters : https://piwik.org/docs/tracking-campaigns-url-builder/

  You will then be able to push additional data to Piwik such as :

  • pk_campaign : the name of your ad campaign
  • pk_kwd : the keyword associated to this campaign
  • pk_source : the source of your campaign
  • pk_medium : the type of source, in our case either cpc, cpm, cpa
  • pk_content : the content of your ad

  If your campaign URL looks like this : https://your-website.com/, your campaign URL will then look like this after adding the campaign parameters :

  https://your-website.com/?pk_campaign=Name-Of-Your-Campaign&pk_kwd=Your-Keyword&pk_source=google&pk_medium=cpc&pk_content=My-Ad-Headline

  As each ad URL can be fired by different keywords and can correspond to different campaigns or headlines, you will need to customize the campaign parameters for each URL.

  Customizing all of your URLs individually would take you a lot of time under circumstances. That’s why you should know, that each URL parameter can be filled automatically in AdWords with a feature called “Tracking template”.

  Simplifying the campaign URL parameters with tracking templates

  You can define tracking templates either at the account, campaign or ad group level. For example, by using a tracking template at the account level, all your campaigns will have the same landing page with the URL parameters you defined in the tracking template. By defining it at the campaign level, it means that all your ad groups within the campaign will have the same landing page and so on and so forth. Any tracking template defined in a campaign, will overwrite a tracking template defined at the account level.

  Tracking template at the account level

  To edit the template at the account level, you need to click on “Settings”, then click on the “Account” settings tab and define your tracking template pattern. For example :

  https://your-website.com/?url={lpurl}&pk_campaign=AdWords&pk_kwd=Your-Keyword&pk_source=google&pk_medium=cpc&pk_content=My-Ad-Headline

  

  This will apply to all your URLs within your account. So it is only useful if your website domain is the same across all your ads. The URL parameter is compulsory here.

  It can be limiting to have a static value for “pk_campaign” and “pk_kwd” so Google allows you to use dynamic insertion, such as follows :

  https://your-landing-page.com/?url={lpurl}&pk_campaign={campaignid}&pk_kwd={keyword}&pk_source=google&pk_medium=cpc&pk_content={creative}

  The “keyword” means that the data is automatically replaced with the keyword which fired the ad within your account.

  Visit the following page if you want to know more about the different dynamic tags that AdWords supports : https://support.google.com/adwords/answer/6305348#urlinsertion

  Tracking template at the campaign level

  If you wish to define a tracking template at the campaign level, you will find this option within the “Campaign” settings under the campaign URL options :

  

  Tracking template at the Ad Group level

  You can also set it at the Ad Group level within the “Ad Group” settings :

  

  As Google mentions : “If you set up URL options at the campaign level, ad group level, or ad level, those settings will override the account-level options“.

  Now that your URLs are properly configured, you will be able to analyze AdWords traffic performances within Piwik once a click is coming from those sources.

  

  Did you like this article ? If yes, do not hesitate to share it or give us your feedback about the topic you would like us to write about.