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• Concatenate four MP4 video files using FFmpeg

  28 juin 2017, par GTAVLover

  I’m trying to concatenate four MP4 video files using FFmpeg. (latest version) Those four mp4 videos differ from general mp4 videos and have specific codecs, I play them in Windows Media Player with the help of K-Lite Mega Codec Pack 13.1.0.

  Codec information of one file (all four files have same codecs) by MediaInfo :

  General

  Complete name               : Testing - 1.mp4
  
  Format                      : MPEG-4
  
  Format profile              : Base Media
  
  Codec ID                    : isom (mp41/avc1)
  
  File size                   : 59.4 MiB
  
  Duration                    : 3 min 47 s
  
  Overall bit rate mode       : Variable
  
  Overall bit rate            : 2 196 kb/s
  
  Writing application         : vlc 2.2.4 stream output
  
  Comment                     : QuickTime 6.0 or greater

  Video

  ID                          : 2
  
  Format                      : AVC
  
  Format/Info                 : Advanced Video Codec
  
  Format profile              : High@L3
  
  Format settings, CABAC      : Yes
  
  Format settings, ReFrames   : 3 frames
  
  Codec ID                    : avc1
  
  Codec ID/Info               : Advanced Video Coding
  
  Duration                    : 3 min 47 s
  
  Bit rate mode               : Constant
  
  Bit rate                    : 2 000 kb/s
  
  Width                       : 720 pixels
  
  Height                      : 576 pixels
  
  Display aspect ratio        : 5:4
  
  Frame rate mode             : Constant
  
  Frame rate                  : 25.000 FPS
  
  Standard                    : PAL
  
  Color space                 : YUV
  
  Chroma subsampling          : 4:2:0
  
  Bit depth                   : 8 bits
  
  Scan type                   : Progressive
  
  Bits/(Pixel*Frame)          : 0.193
  
  Stream size                 : 54.1 MiB (91%)

  Audio

  ID                          : 1
  
  Format                      : AAC
  
  Format/Info                 : Advanced Audio Codec
  
  Format profile              : LC
  
  Codec ID                    : 40
  
  Duration                    : 3 min 47 s
  
  Source duration             : 3 min 46 s
  
  Bit rate mode               : Variable
  
  Bit rate                    : 192 kb/s
  
  Maximum bit rate            : 294 kb/s
  
  Channel(s)                  : 2 channels
  
  Channel positions           : Front: L R
  
  Sampling rate               : 48.0 kHz
  
  Frame rate                  : 46.875 FPS (1024 spf)
  
  Compression mode            : Lossy
  
  Stream size                 : 5.13 MiB (9%)
  
  Source stream size          : 5.13 MiB (9%)

  MP4 video files to be concatenated are "Testing - 1.mp4", "Testing - 2.mp4", "Testing - 3.mp4" and "Testing - 4.mp4".

  I needed to use FFmpeg’s Concatenation method to join those four MP4 files together into one MP4 file.

  First attempt (using Concat Demuxer) :

  FFmpeg -f concat -safe 0 -i "F:\New Text Document.txt" -c copy E:\Testing.mp4

  File concatenated into one MP4 file with several errors and warnings from FFmpeg.

  Non-monotonous DTS in output stream

  SPS NALU is missing or invalid, The resulting stream may not play

  When playing above concatenated file with Windows Media Player, it gives error

  Network is too busy to play file at original quality

  but the file actually in a local hard drive.

  Seek option not working (even in VLC media player) and Windows Explorer showing incorrect duration like 3h 54min, it should be 15min 05s.

  Second attempt (using Concat Demuxer) :

  FFmpeg -f concat -safe 0 -i "F:\New Text Document.txt" -vcodec copy -acodec copy -crf 0 E:\Testing.mp4

  Then file concatenates successfully and plays without any errors in Windows Media Player and VLC media player. The only problem here is file is very big and about 1.2GB in size because Constant Rate Factor is set to 0 to stop WMP network related error.

  Note : Before concatenating (four source files) are playing fine in both players without any errors, but they are medium in size also. As MediaInfo shows, "Testing - 1.mp4" is 59.4 MB, instead huge sizes.

  When I join those using EasiestSoft Video/Audio Joiner 4.7, file produces no errors while playing (I mean everything works fine as expect, but I need a command line tool like FFmpeg to batch process multiple videos), but in version 5.0, it seems to produce this network related error (this may be a program bug, I think it re-encodes even I check don’t re-encode checkbox).

  What can I do with FFmpeg to make this concatenated MP4 file smaller (around total size of four source files) and to make this able to play in both players without any network related issues or incorrect duration issues.

• avcodec : Remove libaacplus

  24 janvier 2016, par Timothy Gu

  avcodec : Remove libaacplus
  TODO : bump minor
  It’s inferior in quality to fdk-aac and has an arguably more problematic
  
  license.
  As early as 2012, a HydrogenAudio user reported :
  > It has however one huge advantage : much better quality at low bitrates than
  
  > faac and libaacplus.
  (https://hydrogenaud.io/index.php?PHPSESSID=ckiq394pdglka0kj2fin6ij8t7&topic=95989.msg804633#msg804633)
  I myself have made a few spectrograms for a comparison of the two
  
  encoders as well. The FDK output is consistently better than the
  
  libaacplus one, in all bitrates I tested.
  libaacplus license is 3GPP + LGPLv2. 3GPP copyright notice is completely
  
  proprietory, as follows :
  > No part may be reproduced except as authorized by written permission.
  
  >
  
  > The copyright and the foregoing restriction extend to reproduction in
  
  > all media.
  
  >
  
  > © 2008, 3GPP Organizational Partners (ARIB, ATIS, CCSA, ETSI, TTA, TTC).
  
  >
  
  > All rights reserved.
  (The latest 26410-d00 zip from 3GPP has the same notice, but the copyright
  
  year is changed to 2015)
  The copyright part of the FDK AAC license (section 2) is a copyleft
  
  license that permits redistribution under certain conditions (and
  
  therefore the LGPL + libfdk-aac combination is not prohibited by
  
  configure) :
  > Redistribution and use in source and binary forms, with or without
  
  > modification, are permitted without payment of copyright license fees
  
  > provided that you satisfy the following conditions :
  
  >
  
  > You must retain the complete text of this software license in
  
  > redistributions of the FDK AAC Codec or your modifications thereto in
  
  > source code form.
  
  >
  
  > You must retain the complete text of this software license in the
  
  > documentation and/or other materials provided with redistributions of
  
  > the FDK AAC Codec or your modifications thereto in binary form.
  
  >
  
  > You must make available free of charge copies of the complete source
  
  > code of the FDK AAC Codec and your modifications thereto to recipients
  
  > of copies in binary form.
  
  >
  
  > The name of Fraunhofer may not be used to endorse or promote products
  
  > derived from this library without prior written permission.
  
  >
  
  > You may not charge copyright license fees for anyone to use, copy or
  
  > distribute the FDK AAC Codec software or your modifications thereto.
  
  >
  
  > Your modified versions of the FDK AAC Codec must carry prominent
  
  > notices stating that you changed the software and the date of any
  
  > change. For modified versions of the FDK AAC Codec, the term
  
  > "Fraunhofer FDK AAC Codec Library for Android" must be replaced by the
  
  > term "Third-Party Modified Version of the Fraunhofer FDK AAC Codec
  
  > Library for Android."
  

  • [DH] Changelog
  • [DH] LICENSE.md
  • [DH] configure
  • [DH] doc/general.texi
  • [DH] doc/platform.texi
  • [DH] libavcodec/Makefile
  • [DH] libavcodec/allcodecs.c
  • [DH] libavcodec/libaacplus.c

• Launch Leech and the History of WMV

  14 septembre 2010, par Multimedia Mike — General

  I was combing through my programming archives again and came across an old Perl script called launch-leech.pl. This was a private script I used to maintain for the benefit of myself and a few friends. See, there was this site called Launch.com (URL doesn’t seem to do anything as of this writing but here’s the Wikipedia page). Purchased by Yahoo ! in 2001, Launch still maintained their independent branding. They also carried a lot of music videos, of which I am a huge junkie. launch-leech.pl was the tool I used to download the videos. This was particularly useful since I stubbornly clung to dialup internet access until mid-2004 and it would have been impossible to stream video at any decent quality (though there were 56k streams, so like I said– not possible at any decent quality).

  
  
  

  Technically
  I followed Launch.com for many years. To be honest, I only “followed” in that I figured out where their “latest videos” URL lived and regularly polled it. Each video had either a 6-, 7-, or 8-digit unique ID that could be plugged into the launch-leech.pl script which would then have a conversation with the relevant servers, determine the correct streaming URL with the highest quality, then download and save the URL by handing it off to an external program (first ASFRecorder, though I later switched to mmsclient).

  At one point, I even wrote a crawler that compiled an offline database of all the videos, their IDs and their metadata. I never thought of anything interesting to do with it, though.

  
  
  

  Windows Media Legacy
  During these glory days of leeching, Launch.com streamed using Windows Media. I admit, it’s a bit of a blur now — the site might have used Real or QuickTime, but I was obviously most in tune with the WM side. I remember when I first found the site circa 2000-2001, the videos were in MS MPEG-4v3, and the high quality bitrate was 300 kbits/sec. Eventually, Launch.com would stream WMV7, WMV8, and finally WMV9, with bitrates up to 700 kbits/sec. However, they never broke free of the 320×240 encoding resolution, which was frustrating. When I wasn’t able to notice any substantial difference between 300 and 700 kbits/sec, I felt it might be time to put those extra bits to work on a resolution upgrade.

  At least they were nice enough to re-encode a number of old videos using better codecs and bitrates with each revision, thus prompting me to scan through the site collecting updated video IDs for download.

  
  
  

  Epilogue
  I don’t clearly remember when I stopped visiting Launch.com. Video-wise, the web has been a blur of Flash video ever since about 2006. Meanwhile, I spent a lot of time collecting a bunch of music videos in the first half of the decade only to find that pretty much every version of every music video made since the dawn of time is available on demand thanks to YouTube. I have found that this phenomenon manifests in many areas as internet technology marches on.

  The Real Entertainment
  The launch-leech.pl tool represents a recurring pattern for me. I derive as much — if not more — entertainment from creating programs like launch-leech.pl (and implicitly reverse engineering something in the process ; in this case, a website) as I do from the intended entertainment media itself. I seem to have this issue a lot with games, too.

  Is this an issue for anyone else ? Am I the only one who would rather play with the box that a shiny toy comes packaged in ?