Windows 7 supports a ton of video codecs by default, but I've found that some of the videos I have will play video but no audio.
Using the MediaInfo application, It looks like the culprit is the DTS-only audio on these video files:
General Complete name : C:\Users\Jeff\Videos\video1.mkv Format : Matroska File size : 7.95 GiB Duration : 2h 13mn Overall bit rate : 8 517 Kbps Encoded date : UTC 2010-10-09 19:46:55 Writing application : mkvmerge v2.9.8 ('C'est le bon') built on Aug 13 2009 12:49:06 Writing library : libebml v0.7.7 + libmatroska v0.8.1 Audio ID : 2 Format : DTS Format/Info : Digital Theater Systems Codec ID : A_DTS Duration : 2h 13mn Bit rate mode : Constant Bit rate : 1 510 Kbps Channel(s) : 6 channels Channel positions : Front: L C R, Side: L R, LFE Sampling rate : 48.0 KHz Bit depth : 24 bits Stream size : 1.41 GiB (18%) Title : English DTS Language : English
(I removed the video section as it isn't relevant)
There is no other audio stream in this file -- only the DTS. Clearly it is the culprit for my "video but no audio" problem. So I have two questions:
- Why can't Windows 7 play back DTS audio out of the box?
- How do you add DTS audio support to Windows 7 without installing a whole bunch of crazy new codecs I don't want or need?