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• lavf/bink : fix latest header and add all existing revisions

  18 août 2017, par bnnm

  lavf/bink : fix latest header and add all existing revisions
  KB2 'i' found in Life is Strange (Xbox 360), rest verified against binkconv.exe
  Signed-off-by : bnnm <bananaman255@gmail.com>
  
  Signed-off-by : Michael Niedermayer <michael@niedermayer.cc>
  

  • [DH] libavformat/bink.c

• Evolution of Multimedia Fiefdoms

  1er octobre 2014, par Multimedia Mike — General

  I want to examine how multimedia fiefdoms have risen and fallen through the years.

  
  
  

  Back in the day, the multimedia fiefdoms were built around the formats put forth by competing companies : there was Microsoft/WMV, Apple/MOV, and Real/RM as the big contenders. On2 always wanted to be a player in this arena but could never quite catch a break. A few brave contenders held the line for open source and also for the power users who desired one application that could handle everything (my original motivation for wanting to get into multimedia hacking).

  The computer desktop was the battleground for internet-based media stream. Whatever happened to those days ? Actually, if memory serves, Flash-based video streaming stepped on all of them.

  Over the last 6-7 years, the battleground has expanded to cover mobile devices, where Flash’s impact has… lessened. During this time, multimedia technology pretty well standardized on a particular stack, namely, the MPEG (MP4/H.264/AAC) stack.

  The belligerents in this war tried for years to effectively penetrate new territory, namely, the living room where the television lived. This had been slowgoing for years due to various user interface and content issues, but steadily improved.

  Last April, Amazon announced their entry into the set-top box market with the Fire TV. That was when it suddenly crystallized for me that the multimedia ecosystem has radically shifted. Now, the multimedia fiefdoms revolve around access to content via streaming services.

  Off the top of my head, here are some of the fiefdoms these days (fiefdoms I have experience using) :

  • Netflix (subscription streaming)
  • Amazon (subscription, rental, and purchased streaming)
  • Hulu Plus (subscription streaming)
  • Apple (rental and purchased media)

  I checked some results on Can I Stream.It ? (which I refer to often) and found a bunch more streaming fiefdoms such as Google (both Play and YouTube, which are separate services), Sony, Xbox 360, Crackle, Redbox Instant, Vudu, Target Ticket, Epix, Sony, SnagFilms, and XFINITY StreamPix. And surely, these are probably just services available in the United States ; I know other geographical regions have their own fiefdoms.

  What happened ?

  When I got into multimedia hacking, there were all these disparate, competing ecosystems. As a consumer, I didn’t care where the media came from, I just wanted to play it. That’s what inspired me to work on open source multimedia projects. Now I realize that I have the same problem 10-15 years later : there are multiple competing ecosystems. I might subscribe to fiefdoms X and Y, but am frustrated to learn that something I’d like to watch is only available through fiefdom Z. Very few of these fiefdoms can be penetrated using open source technology.

  I’m not really sure about the point about this whole post. Multimedia technology seems really standardized these days. But that’s probably just my perspective because I have spent way too long focusing on a few areas of multimedia technology such as audio and video coding. It’s interesting that all these services probably leverage the same limited number of codecs. Their differentiation comes from the catalog of content that each is able to license for streaming. There are different problems to solve in the multimedia arena now.

• FFMPEG encode audio and forced subtitles at same time ?

  8 janvier 2017, par Nick Bell

  I’m using latest static build of ffmpeg windows.

  My input file (.mkv) is :

  [video] - 1080, V_MPEG4/ISO/AVC, 14.6 Mbps, ID#0
  
  [audio] - DTS 5.1, 1510 Kbps, ID#1
  
  [subtitles] - S_TEXT/ASS Lossless English, ID#14

  My problem is this : I convert the audio, so that my target player, a XB1 console (media support faq), is able to play audio/video. However sometimes its rather difficult to hear or parts may be in foreign language, so I want to force the english subtitles into the mix at the same time I convert the audio.

  Currently for the audio, I use the following command

  ffmpeg -i input.mkv -codec copy -acodec ac3 output.mkv

  Can I somehow tie in the forced subtitles (onto the video) in order to save an extra process of taking the output.mkv and trying to force subtitles on ?

  Edit : I’ve tried using the following command to extract subtitles to be able to edit them

  ffmpeg -i Movie.mkv -map 0:s:14 subs.srt

  However i get the error : Stream map '0:s:14' matches no streams

  Edit2 : attempted to extract subtitles and succeeded with

  ffmpeg -i input.mkv -map 0:14 -c copy subtitles.ass

  but still looking to force the subtitles, nonetheless !

  Also - a little bonus to this question - can I somehow extract the .ass file and edit it to only produce subtitles for foreign parts - so english audio doesn’t have subtitles during the movie but foreign audio does have subtitles ?

  Cheers

  Edit3 :

  When I try to use both of the commands at once (my earlier mentioned audio converter & one from the ffmpeg wiki)

  ffmpeg -i input.mkv -codec copy -acodec ac3 -vf "ass=subs.ass" output.mkv

  I get the following error from ffmpeg,

  Filtergraph 'ass=subs.ass' was defined for video output stream 0:0 but codec copy was selected.
  
  Filtering and streamcopy cannot be used together.