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• Solving The XVD Puzzle

  15 avril 2012, par Multimedia Mike — General, multimedi archaeology, silicon valley, vg2, xvd, zygo

  I downloaded a multimedia file a long time ago (at least, I strongly suspected it was a multimedia file which is why I downloaded it). It went by the name of ‘lamborghini_850kbps.vg2′. I have had it in my collection for at least 7 years. I couldn’t remember where I found it. I downloaded it before it occurred to me to take notes about this sort of stuff.

  I found myself staring at the file again today and Googled the filename. This led me to a few Japanese sites which also contained working URLs for a few more .vg2 samples. Some other clues led me to a Russian language forum where someone had linked to a site that had Win32 codec modules that could process the files. The site was defunct but the Internet Archive Wayback Machine kept a copy for me, as well as copies of several more .vg2 samples from a defunct Japanese site previously involved with this codec.

  Sometimes this internet technology works really well. But I digress.

  Anyway, through all this, I finally found a clue : XVD. and wouldn’t you know, there is already a basic page on the MultimediaWiki describing the technology. In fact, while VG2 is a custom container, the MultimediaWiki states that the video component has a FourCC of VGMV, and there is already a file named VGMV.avi in the root V-codecs/ samples directory, something I vow to correct (that’s a big pet peeve of mine– putting samples in the root V-codecs/ or A-codecs/ directories).

  XVD… XVD… XVD… why does that sound so familiar ? Oh, of course ; there is a company named XVD and they have an office in the Bay Area which I have passed on numerous occasions, like this morning :

  
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  Someone originally connected with the multimedia technology in question operates a website which contains an unofficial history of the XVD tech. At first, I was wondering if the technology was completely defunct (and should therefore be open sourced). But if XVD’s solutions page (dated 2010) is to be believed, the technology is still in service, and purported to be better than H.264 and VC-1 : “The current generation of XVD video compression technology provides better video quality at any given data rate than standards-based codecs (H.264 or VC-1) with four times lower encoding complexity (when compared with H.264 Main Profile).”

  If they say so. For my part, I’m just happy that I have finally figured out what this lamborghini_850kbps.vg2 is so that I can properly catalog it on the samples site, which I have now done, along with other samples and various codecs modules.

  This episode reminds me that there’s a branch office of Zygo Corporation close to my home (though the headquarters are far, far away). The companies you see in Silicon Valley. Anyway, long-time open source multimedia hackers will no doubt recognize Zygo from the ZyGo FourCC & video codec transported in QuickTime files that was almost decode-able using an H.263 decoder.

  
  
  

  I may never learn what Zygo’s core competency actually is, but I will always remember their multimedia tech every time I run past their office.

• FFmpeg make mpeg2 ts without discontinuity

  31 mai 2012, par user1427162

  I have many MOV files recorded with iPhone and I want to convert them to mpeg2 TS. I want to use them for live video streaming with HTTP Live Streaming protocol.

  I set my iPhone to continiously send MOV files to server. Every video clip is 5 seconds long. I want to make mpeg2 TS out of them and add their urls to m3u8 playlist.
  I managed to do all of that, but when I try to play the stream VLC player plays only first two files in playlist, and last file in playlist at that moment.
  I searched the internet and I think this has something to do with discontinuity.

  Is there any way to convert multiple MOV files into multiple mpeg2 TS segments without discontinuity ?

  Or maybe I'm doing something else wrong ?
  Here is my ffmpeg command :

  ffmpeg.exe -i input,MOV -f mpegts output.ts

  and here is my m3u8 list :

  #EXTM3U
  
  #EXT-X-PLAYLIST-TYPE:EVENT
  
  #EXT-X-TARGETDURATION:10
  
  #EXT-X-MEDIA-SEQUENCE:0
  
  #EXT-X-MEDIA-SEQUENCE:0
  
  #EXTINF:10,
  
  fileSequence0.ts
  
  #EXTINF:10,
  
  fileSequence1.ts
  
  #EXTINF:10,
  
  fileSequence2.ts

  Thanks in advance

• FFMPEG - Correct command line parameters to create a H.264 Streaming MP4 from a set of images

  27 septembre 2021, par Adam

  I have no problems viewing a video created by my current parameters in a HTML5 browser, Flash player, Windows Phone 7, Android Phone, etc. However, they won't display on iPhone or iPad. If I modify the video using Super and select "Enable Streaming" checkbox they work on iPhone and iPad suddenly. We are suspecting that my command line parameters are incorrect for enabling h.264 streaming and are instead generating a "progressive download" video.

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  I'm pretty new to FFMPEG and don't understand a lot of the parameters. Can anyone help correct my existing parameters, or maybe provide the missing parameters, etc ?

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  Thanks in advance.

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  My current FFMPEG command line paramters are :

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  ffmpeg.exe 
 -r 30 
 -threads 4 
 -f image2 
 -i .\frame%05d.jpg 
 -i audioFile  
 -acodec aac 
 -ab 128k 
 -ar 44100
 -vcodec h264 
 -crf 27 
 -coder 1 
 -flags +loop 
 -cmp +chroma 
 -partitions +parti4x4+partp8x8+partb8x8 
 -me hex 
 -subq 5 
 -me_range 16 
 -g 60 
 -keyint_min 25 
 -sc_threshold 40 
 -i_qfactor 0.71 
 -b_strategy 1 
 out.mp4


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