Since updating from 7.3.0 to 7.3.1 I'm finding that Quicktime won't play the video on .mp4 files, it plays the audio just fine, but shows a blank screen. The strangest part is that it's fine on two other computers, only one, a G4 iMac (800MHz, 512mb). Is it simply the low spec of the computer?
Open one of the files and then open the Movie Inspector window to view the codecs used in it.
7.3.1 has dropped support for Flash Media and they display as a black window.
Something odd about your QuickTime install and I wouldn't have noticed it without seeing your screen shot.
Version 7.3.1 uses a new window format for the Movie Inspector window:
Yours is the older window display (black and white) and I suspect something went wrong with your 7.3.1 install. This may have corrupted the MPEG-4 decoder used by QuickTime.
See if you can install 7.3.1 again.
Hmm, tried that and it didn't seem to make a difference. The old-style window is also on the working computers, could it be to do with the fact that I'm still running 10.4, not Leopard?
I would venture to guess that you are using an unsupported machine and there is no Core Image support on your graphics card and possibly the one lacks quartz extreme as well. So it is the low spec on the graphics card. Going back to an earlier version of QT may resolve the issue. If you don't have a CoreImage supported GC you will never get the transparent window or the video settings in the A/V controls.
I am having problems with .mp4 as well. All my .mp4 files will not open correctly in QT. Movie Inspector shows that all the files dimensions have been altered to display "0" height in pixels. Have tried correcting dimensions and saving/exporting, to no avail. Sound is fine.
Files open in VLC and MPlayer OSX. Tried re-installing QT and Flip4Mac. Nothing. Ideas?
I am going though the exact same problem, I've spent 2 hrs wit tech support and there unable to address the issue. They say its problem with the content, Please help
I just noticed this same problem. The movies open fine in iTunes but not with QuickTime Pro version 7.4. Audio plays but not video. I've been converting files from YouTube to use with my chemistry classes all semester. I'm a teacher. I use iSquint and save them as mp4 files. This has worked fine until the last QuickTime update.
Same problem here after installing the latest version version of QuickTime, 7.4 on my PowerMac G5 running the latest version of Leopard. Some of my videos play fine others only play audio.
It's a problem with QuickTime, if you search this forum you'll see this is a wide spread problem with 7.4.
Hope Apple is aware of this and is able to fix it soon.
I'm having the same problem after downloading the Quicktime 7.4 update. (I'm on in iMac G5 running 10.3.9).
I had asked about this problem in the Using Mac OSX folder and a very nice and helpful poster, littleshoulders, offered a solution that has apparently worked for some:
"Go to HD/Library/Internet Plugins folder and drag the QuickTime Plugin.webplugin folder to your desktop. Try again and see if this fixes your problem. If it does just drag the problematic folder to somewhere on your HD to store it such as your Documents folder."
It didn't work for me, but I thought I'd post it here in case it helps someone else.
Can anyone tell me how to uninstall Quicktime and install an earlier version (or let me know if this is not advisable?) Ah, for the days when you'd just drag an app into the trash...
This really ticks me off. This is a BIG problem, so you'd think Apple would come out with a fix, or at least acknowledge the problem and let us know that they are working on a fix.