Some videos not playing in Quicktime but WILL play on VLC Player

Question

Hello,
All of a sudden, some of my video files will not play on Quicktime. OT reads the length of the movie but when I click play, all I get is a black screen and no sound even though the progress bar rolls per usual. When I open the videos in my VLC Player, the play just fine. This is not with all of my movies. Some movies play fine in Quicktime. Also, if this helps, Final Cut X will not recognize these movie files for import. Am using Quicktime 10.1.
Thoughts? Help? Anyone?
Thanks,
John

Answer 1

Jon Walker wrote:
The .dv videos that will NOT play:
I suspect you may have a number of problems here. The first is having elementary DV and PCM audio streams in a DV stream file container. (I.e. DV/DV audio and video stream data is normally stored in the DV file container while DV/PCM data is normally wrapped in the MOV file container.) The second problem is the fact that the DV video seems to be missing the aspect ratio "aware" information. As you can see from the playing file, the format line should read either
720 x 480 (640 x 480)
or
720 x 480 (853 x 480)
Based on this, I am wondering how old this file may be and/or how it was captured. (I.e., the playback problem may be due to file container not being compatible with the QT X player which, in fact, relies on an embedded aspect ratio parameter rather than the QT 7 embedded "Current Size" setting and is not expecting PCM audio to be contained in a DV stream file container.
These videos are older (almost 10 years old) and they were edited in iMovie HD.
In addition, there is a question (at least for me) as to whether the DV video streams are embedded sequentially or as alternative video tracks. (I.e., if you have QT 7 Pro installed, please post a copy of the "Properties" window.
Installed QT 7 and videos play fine. No issues. I don't have QT7 Pro.
Not sure if this will work, but if I had a copy of the non-playing file, the first thing I would try would be to open the file in MPEG Streamclip and re-save the data to a "real" MOV file container to see if it would then be playback compatible with the QT X player app.
Tried Streamclip and it will save as MOV but the size changes (from 640x480 to 720x480 and I get a stretched look. OT X will play it however. Tried to "export" using differrent formats but with mixed results. Sometimes I got sound but no video. I will continue to fiddle with settings but it doesn't seem like a reliable path to go down.
Could I be missing the codec component? Is there a way to check?
Not very likely if any files play have the same video compression format. Had the non-playing files been encoded with one of the HD DV codecs, then yes, that might have been a possibility whould could have been checked.
Would your answer be the same now that we know QT7 plays the videos without any issues?
Exported out to a .dv file. Format exact same as the working one above. Plays fine.
Of course. You exported the audio and video as a DV compressed data in DV stream file container. Thus, both the file format and compression format are now QT X compatible.
The container is a .dv. I did rename it to .mov at one point to see if that helped but got the same result.
Of course. Changing the file extension is like calling a cup of coffee a glass of coffee—i.e., the coffee is still in a cup. Basically, this only works if the data in the container is already compatible with the file container and the container is compatible with the player. For instance, H.264/AAC compressed data will play in either QT 7 or QT X players whether it is in an MOV, MP4, or M4V file container. On the other hand, "muxed" MPEG-2/AC3 data won't play in the QT X v10.2 player with a VOB file extension but will play if you change the extension to TS or MPG. On the other hand, the VOB or MPG file (with the QT MPEG-2 playback codec component installed) will play in both QT 7 (without audio) and MPEG Streamclip while the TS file won't open in the QT 7 player but plays fine with audio in MPEG Streamclip.
I THINK I understand! : )
I do have a DropBox folder.
If you also have an online DropBox account, then yes, that would be a good method for posting large files. You then only have to post or email the URL to the people you want to have access to the data.
True. One of the issues is that I want to re-edit some of these files which means I need to get them into FCP. I know there is a workaround, i.e. importing them into iMovie like I did and then spitting them out again so they will play but I feel like I am losing quality that way. Aren't I? This was before I started saving projects so I could always go back into them. Plus, I really want to preserve the original files for backup sake.
Jon, thanks again for taking your time with me. Really apprecite it.