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• Correct Complex Lens Distortion in FFMPEG (or OpenCV) [closed]

  29 septembre 2024, par C.M.

  I need to process videos which were taken with a wide angle vehicle camera. A good example is this frame from a video :

  


  

  


  As you can see, the image is pretty distorted and I need to correct that. After some research, neither a Barrel distortion or a Pincushion distortion is the case here. I'd say it depends on the axis. The x axis seems to have a Pincushion distortion, but the y axis seems to have a Barrel distortion.

  


  In my project I use a Java backend and I use FFmpeg to process the videos (re-encoding, color correction, ...). Therefore I'd like to do this in FFmpeg as another video filter.

  


  I tried to use the lenscorrection filter but couldn't find any suitable values for k1 and k2. IMHO this isn't even possible since the filter can only handle the two types of distortion mentioned above. Here are two examples where I tried to correct the horizontal and vertical elements of the image :

  


  

  


  (with k1= -0.7, k2=0.4)

  


  

  


  (with k1=0.7)

  


  But the resulting image would need to look like this (just roughly edited with GIMP) :

  


  

  


  Is this even possible with FFmpeg filters ? I already tried out the v360 filter (similar like in this article) but just achieved similar results.

  


  If I'm correct this isn't possible with video filters. So I thought of doing this in OpenCV in Java by extracting all the frames with FFmpeg, transforming them with OpenCV and rendering them to a video again. Unfortunately I have no experience with OpenCV and couldn't get any results. I think this should be possible in some way.

  


  Can someone help me ?

  


• Use Google Analytics and risk fines, after CJEU ruling on Privacy Shield

  27 août 2020, par Joselyn Khor — Privacy
  EU websites using Google Analytics and Facebook are being targeted by European privacy group noyb after the invalidation of the Privacy Shield. They filed a complaint against 101 websites for continuing to send data to the US. 

  “A quick analysis of the HTML source code of major EU webpages shows that many companies still use Google Analytics or Facebook Connect one month after a major judgment by the Court of Justice of the European Union (CJEU) - despite both companies clearly falling under US surveillance laws, such as FISA 702. Neither Facebook nor Google seem to have a legal basis for the data transfers.”

  

  The Privacy Shield previously allowed for EU data to be transferred to the US. However, this was invalidated by the Court of Justice of the European Union (CJEU) on July 16, 2020. The CJEU deemed it illegal for any websites to transfer the personal data of European citizens to the US. 

  They also made it clear in a press release that “data subjects can claim compensation for inadmissible data exports (marginal no. 143 of the judgment). This should in particular include non-material damage (“compensation for pain and suffering”) and must be of a deterrent amount under European law.” Which puts extra financial pressure on websites to take the new ruling seriously.

  Immediate action is required after Google Privacy Shield invalidation

  The Berlin Commissioner for Data Protection and Freedom of Information therefore calls on all those responsible under its supervision to observe the decision of the ECJ [CJEU]. Those responsible who transfer personal data to the USA - especially when using cloud services - are now required to immediately switch to service providers in the European Union or in a country with an adequate level of data protection.

  As the ruling is effective immediately, there’s a pressing need for websites using Google Analytics to act, or face getting fined.

  What does this mean for you ?

  If you’re using Google Analytics the safest bet is to stop using it immediately. 

  "Neither Google Analytics nor Facebook Connect are necessary for the operation of these websites and could therefore have been replaced or at least deactivated in the meantime."

  If you still need to use it, then you’ll need to inform your visitors via a clear consent screen. This banner needs to make clear their personal data will be sent to the US, and to educate them about any potential risk related to this. They will then need to explicitly agree to this. 

  Another downside of cookie consent screens is that you may also suffer a damaging loss of visitors. After implementing cookie consent best practices, the UK’s data regulator the Information Commissioner’s Office (ICO) found a 90% drop in traffic, “implying a ninety percent drop in opt-in rates.”

  With an acceptance rate for such consent screens being lower than 10% your analytics becomes guesswork rather than science. 

  Looking for a privacy-respecting alternative to Google Analytics ?

  Privacy compliant Matomo Analytics is one of the best Google Analytics alternatives availalble. 

  With Matomo you’re able to continue using analytics without facing the wrath of both the GDPR and the CJEU. Matomo On-Premise lets you choose where your data is stored, so you can ensure no data is processed in the US. 

  Matomo is privacy-friendly and can be tweaked to comply with all privacy laws. Including the GDPR, HIPAA, CCPA and PECR. The benefits of this include : not needing to use tracking or cookie consent screens (like with GA) ; and avoiding fines because no personal data is collected. You also get 100% accurate data and the ability to protect your user’s privacy.

  Download Matomo

  

  Is your EU business at risk of being fined for using Google Analytics ?

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  Get our assessment guide

• ffmpeg issue after adding background audio

  9 avril 2021, par spicy

  So I have an issue to which I cannot find an answer. I have a video which is 7min 38sec long after concat. When I want to add background audio to this video it cuts off the last 7sec of the original video. I cannot find the reason.

  


  If anyone could help me in any way, it would be amazing because I have been troubleshooting this past 3 days.

  


  My FFmpeg version is ffmpeg version 4.2.3 Copyright (c) 2000-2020 the FFmpeg developers.

  


  For concat I use this : FFmpeg -f concat -safe 0 -i txtfile.txt -c copy -ac 2 output.mp4

  


  For adding background audio I use this : ffmpeg -i output.mp4 -i background.mp3 -c:v copy -filter_complex "[0:a]aformat=fltp:44100:stereo,apad[0a];[1]aformat=fltp:44100:stereo,volume=0.2[1a];[0a][1a]amerge[a]" -map 0:v -map "[a]" -ac 2 -shortest output_with_background.mp4

  


  And the console output while doing its stuff is :

  


  ffmpeg version 4.2.3 Copyright (c) 2000-2020 the FFmpeg developers
  built with gcc 9.3.1 (GCC) 20200523
  configuration: --enable-gpl --enable-version3 --enable-sdl2 --enable-fontconfig --enable-gnutls --enable-iconv --enable-libass --enable-libdav1d --enable-libbluray --enable-libfreetype --enable-libmp3lame --enable-libopencore-amrnb --enable-libopencore-amrwb --enable-libopenjpeg --enable-libopus --enable-libshine --enable-libsnappy --enable-libsoxr --enable-libtheora --enable-libtwolame --enable-libvpx --enable-libwavpack --enable-libwebp --enable-libx264 --enable-libx265 --enable-libxml2 --enable-libzimg --enable-lzma --enable-zlib --enable-gmp --enable-libvidstab --enable-libvorbis --enable-libvo-amrwbenc --enable-libmysofa --enable-libspeex --enable-libxvid --enable-libaom --enable-libmfx --enable-amf --enable-ffnvcodec --enable-cuvid --enable-d3d11va --enable-nvenc --enable-nvdec --enable-dxva2 --enable-avisynth --enable-libopenmpt
  libavutil      56. 31.100 / 56. 31.100
  libavcodec     58. 54.100 / 58. 54.100
  libavformat    58. 29.100 / 58. 29.100
  libavdevice    58.  8.100 / 58.  8.100
  libavfilter     7. 57.100 /  7. 57.100
  libswscale      5.  5.100 /  5.  5.100
  libswresample   3.  5.100 /  3.  5.100
  libpostproc    55.  5.100 / 55.  5.100
[mov,mp4,m4a,3gp,3g2,mj2 @ 0000024baee72440] Auto-inserting h264_mp4toannexb bitstream filter
Input #0, concat, from 'C:\Users\shooey\Desktop\junky\Content\07-04-2021\videos.txt':
  Duration: N/A, start: -0.023220, bitrate: 18916 kb/s
    Stream #0:0(und): Video: h264 (High) (avc1 / 0x31637661), yuv420p, 1920x1080 [SAR 1:1 DAR 16:9], 18861 kb/s, 30 fps, 30 tbr, 15360 tbn, 60 tbc
    Metadata:
      handler_name    : VideoHandler
    Stream #0:1(und): Audio: aac (LC) (mp4a / 0x6134706D), 44100 Hz, stereo, fltp, 54 kb/s
    Metadata:
      handler_name    : SoundHandler
File 'C:\Users\shooey\Desktop\junky\Content\07-04-2021\output.mp4' already exists. Overwrite ? [y/N] y
Output #0, mp4, to 'C:\Users\shooey\Desktop\junky\Content\07-04-2021\output.mp4':
  Metadata:
    encoder         : Lavf58.29.100
    Stream #0:0(und): Video: h264 (High) (avc1 / 0x31637661), yuv420p, 1920x1080 [SAR 1:1 DAR 16:9], q=2-31, 18861 kb/s, 30 fps, 30 tbr, 15360 tbn, 15360 tbc
    Metadata:
      handler_name    : VideoHandler
    Stream #0:1(und): Audio: aac (LC) (mp4a / 0x6134706D), 44100 Hz, stereo, fltp, 54 kb/s
    Metadata:
      handler_name    : SoundHandler
Stream mapping:
  Stream #0:0 -> #0:0 (copy)
  Stream #0:1 -> #0:1 (copy)
Press [q] to stop, [?] for help
[mov,mp4,m4a,3gp,3g2,mj2 @ 0000024baee72440] Auto-inserting h264_mp4toannexb bitstream filter
    Last message repeated 5 times
[mov,mp4,m4a,3gp,3g2,mj2 @ 0000024baeeec180] Auto-inserting h264_mp4toannexb bitstream filter
[mov,mp4,m4a,3gp,3g2,mj2 @ 0000024baee72440] Auto-inserting h264_mp4toannexb bitstream filter
    Last message repeated 14 times
[mov,mp4,m4a,3gp,3g2,mj2 @ 0000024baee72440] Auto-inserting h264_mp4toannexb bitstream filter
    Last message repeated 20 times
[mov,mp4,m4a,3gp,3g2,mj2 @ 0000024baee72440] Auto-inserting h264_mp4toannexb bitstream filter
    Last message repeated 7 times
frame=   52 fps= 42 q=-1.0 Lsize=    7838kB time=00:07:38.82 bitrate= 139.9kbits/s speed= 374x
video:4802kB audio:2956kB subtitle:0kB other streams:0kB global headers:0kB muxing overhead: 1.044608%
ffmpeg version 4.2.3 Copyright (c) 2000-2020 the FFmpeg developers
  built with gcc 9.3.1 (GCC) 20200523
  configuration: --enable-gpl --enable-version3 --enable-sdl2 --enable-fontconfig --enable-gnutls --enable-iconv --enable-libass --enable-libdav1d --enable-libbluray --enable-libfreetype --enable-libmp3lame --enable-libopencore-amrnb --enable-libopencore-amrwb --enable-libopenjpeg --enable-libopus --enable-libshine --enable-libsnappy --enable-libsoxr --enable-libtheora --enable-libtwolame --enable-libvpx --enable-libwavpack --enable-libwebp --enable-libx264 --enable-libx265 --enable-libxml2 --enable-libzimg --enable-lzma --enable-zlib --enable-gmp --enable-libvidstab --enable-libvorbis --enable-libvo-amrwbenc --enable-libmysofa --enable-libspeex --enable-libxvid --enable-libaom --enable-libmfx --enable-amf --enable-ffnvcodec --enable-cuvid --enable-d3d11va --enable-nvenc --enable-nvdec --enable-dxva2 --enable-avisynth --enable-libopenmpt
  libavutil      56. 31.100 / 56. 31.100
  libavcodec     58. 54.100 / 58. 54.100
  libavformat    58. 29.100 / 58. 29.100
  libavdevice    58.  8.100 / 58.  8.100
  libavfilter     7. 57.100 /  7. 57.100
  libswscale      5.  5.100 /  5.  5.100
  libswresample   3.  5.100 /  3.  5.100
  libpostproc    55.  5.100 / 55.  5.100
Input #0, mov,mp4,m4a,3gp,3g2,mj2, from 'C:\Users\shooey\Desktop\junky\Content\07-04-2021\output.mp4':
  Metadata:
    major_brand     : isom
    minor_version   : 512
    compatible_brands: isomiso2avc1mp41
    encoder         : Lavf58.29.100
  Duration: 00:07:38.85, start: 0.000000, bitrate: 139 kb/s
    Stream #0:0(und): Video: h264 (High) (avc1 / 0x31637661), yuv420p, 1920x1080 [SAR 1:1 DAR 16:9], 87 kb/s, 0.12 fps, 30 tbr, 15360 tbn, 60 tbc (default)
    Metadata:
      handler_name    : VideoHandler
    Stream #0:1(und): Audio: aac (LC) (mp4a / 0x6134706D), 44100 Hz, stereo, fltp, 52 kb/s (default)
    Metadata:
      handler_name    : SoundHandler
Input #1, mp3, from 'C:\Users\shooey\Desktop\junky\Content\assets\background.mp3':
  Metadata:
    major_brand     : dash
    Software        : Lavf57.56.101
    minor_version   : 0
    compatible_brands: iso6mp41
  Duration: 00:20:03.02, start: 0.025057, bitrate: 167 kb/s
    Stream #1:0: Audio: mp3, 44100 Hz, stereo, fltp, 167 kb/s
    Metadata:
      encoder         : LAME3.100
File 'C:\Users\shooey\Desktop\junky\Content\07-04-2021\output_bckg.mp4' already exists. Overwrite ? [y/N] y
Stream mapping:
  Stream #0:1 (aac) -> aformat
  Stream #1:0 (mp3float) -> aformat
  Stream #0:0 -> #0:0 (copy)
  amerge -> Stream #0:1 (aac)
Press [q] to stop, [?] for help
[Parsed_amerge_4 @ 0000017093965c80] No channel layout for input 1
[Parsed_amerge_4 @ 0000017093965c80] Input channel layouts overlap: output layout will be determined by the number of distinct input channels
Output #0, mp4, to 'C:\Users\shooey\Desktop\junky\Content\07-04-2021\output_bckg.mp4':
  Metadata:
    major_brand     : isom
    minor_version   : 512
    compatible_brands: isomiso2avc1mp41
    encoder         : Lavf58.29.100
    Stream #0:0(und): Video: h264 (High) (avc1 / 0x31637661), yuv420p, 1920x1080 [SAR 1:1 DAR 16:9], q=2-31, 87 kb/s, 0.12 fps, 30 tbr, 15360 tbn, 15360 tbc (default)
    Metadata:
      handler_name    : VideoHandler
    Stream #0:1: Audio: aac (LC) (mp4a / 0x6134706D), 44100 Hz, stereo, fltp, 128 kb/s (default)
    Metadata:
      encoder         : Lavc58.54.100 aac
frame=   52 fps=5.5 q=-1.0 Lsize=   11993kB time=00:07:31.67 bitrate= 217.5kbits/s speed=  48x
video:4802kB audio:7111kB subtitle:0kB other streams:0kB global headers:0kB muxing overhead: 0.670061%
[aac @ 00000170935b4980] Qavg: 319.394