Why won't .mp4 file open in QT 10.0 (or iMovie'09) and OS 10.6.8?

Question

I'm trying to edit some .mp4 movie files, but I can't open them in Quicktime (10.0 or 7.6.6), or iMovie '09 (8.0.6) or Final Cut Express (4.0.1).  I've got a MacBook Pro running OS X 10.6.8 (Snow Leopard).  When I try to open the file in QT 10, it says "The document “name.mp4” could not be opened"; whereas in QT 7 it says "The file could not be opened.  An invalid sample description was found in the movie."  In iMovie, the file is greyed out when I try to import it.
The file will open and play fine in VLC, but I can't do the editing I want there.  The Media Information pane in VLC says: the codec is "H264 - MPEG-4 AVC (part 10)(avc1)", it is HD resolution (1920 x 1080), it has a frame rate of 59.940060, and the Decoded format is "Planar 4:2:0 YUV".  It also has an audio track (MPEG audio) and a subtitle track.  I also tried opening these .mp4 files on two Mac laptops that a friend of mine has.  Interestingly, they would not open on one (I think running Lion with QT 10.0), but they DID open on the other newer laptop (running Mountain Lion with QT 10.2). 
I first assumed it was just a case of not having the right codec.  So I tried copying all the codecs from the Mac laptop that *could* open them, but that didn't work.  Then I searched for and downloaded codecs that I might be missing, such as "avc1Decoder.dmg" from MyCometG3 and http://www.macupdate.com/app/mac/23875/avc1decoder, and x264Encoder 1.2.27 also from MyCometG3, and I put them in my Library/Quicktime folder and restarted Quicktime, but neither solved the problem.  I also tried opening the .mp4 files in MPEG Streamclip (1.9.2), but it says "File open error: unrecognized file type".  When I tell it to "open anyway" it tries and then says "File open error: can't find video or audio tracks".
I tried opening one of these .mp4 files in Handbrake (0.9.8) and it was able to open and convert the file to an .mp4 that is then openable in QT 10 with a format of H.264, AAC, and a reduced frame rate of 29.84.  However, this doesn't seem like a good solution because it takes about 2 hours to convert a file with 30 minutes of video.  I just want to be able to trim these big files down to some short video clips that are in an accessible format.
Any help would be MUCH appreciated.  Am I missing the right codec?  Or, as I'm beginning to wonder, is this format one that is too demanding for OS 10.6.8 and QT 10 and they just cannot handle it no matter what codecs I have on my computer (because of the 60 fps frame rate?  Or is it the subtitle track?).  Or is the solution to upgrade my operating system to Mountain Lion (10.8) and QT 10.2?  My 15" MacBook Pro is about 2 years old with a 2.66 GHz Intel Core i7 and 4 GB of RAM (1067 MHz DDR3).  Thanks.

Answer 1

Wow! A lot of ifs, ands, and maybes here.
I'm trying to edit some .mp4 movie files, but I can't open them in Quicktime (10.0 or 7.6.6), or iMovie '09 (8.0.6) or Final Cut Express (4.0.1).  I've got a MacBook Pro running OS X 10.6.8 (Snow Leopard).  When I try to open the file in QT 10, it says "The document “name.mp4” could not be opened"; whereas in QT 7 it says "The file could not be opened.  An invalid sample description was found in the movie."  In iMovie, the file is greyed out when I try to import it.
To start off with, these messages and/or inability to opent/import files could stem from either security updates that see something in the file that it interprets as a possible breach of file integrity or the inclusion of data not expected in the associated file type while missing codecs are either identified and load but do not display or refuse to load but issue a message to that effect and possibly asking if you want to visit a web page containing codes you may want to add.
The file will open and play fine in VLC, but I can't do the editing I want there.  The Media Information pane in VLC says: the codec is "H264 - MPEG-4 AVC (part 10)(avc1)", it is HD resolution (1920 x 1080), it has a frame rate of 59.940060, and the Decoded format is "Planar 4:2:0 YUV".  It also has an audio track (MPEG audio) and a subtitle track.  I also tried opening these .mp4 files on two Mac laptops that a friend of mine has.  Interestingly, they would not open on one (I think running Lion with QT 10.0), but they DID open on the other newer laptop (running Mountain Lion with QT 10.2).
In the future, could you be more specific when describing the file contents. For the moment, I will assume the video is H.264 (MPEG-4/AVC) and the audio is AAC (MPEG-4) audio and not MPEG-1 layered audio. (I.e., while the former is to be expected with the MP4 file extension, some apps can "stuff" incompatible data into an MP4 container or users can manually change the file extemsion.) It also important to know if the "subtitle" track is embedded within the file or is contained in a separate file. (I.e., a screen capture of the media "info", "inspector", or "properties" window is usually the least ambiguous way to track content information.) It would also be nice to know if the VLC frame rate is for progressive or interlaced video if possible.
Basically, some apps are very touchy about file extensions and track content. iMovie '08, for instance, will not open a file containing extraneous tracks like 'tween, text, chapter, etc. embedded within the file. I assume this may also be true for "subtitle" tracks as far as your Snow Leopard players are concerned. In any case, if your version of the QT 7 player is keyed for "pro" use, I would perform a simple test here by deleting the "subtitle" track, saving the file, and then re-trying to load, open, play, and/or import the file in the various applications currently giving you problems. If this fixes the problem, then you will know the source and solution of your problem
I first assumed it was just a case of not having the right codec.  So I tried copying all the codecs from the Mac laptop that *could* open them, but that didn't work.  Then I searched for and downloaded codecs that I might be missing, such as "avc1Decoder.dmg" from MyCometG3 and http://www.macupdate.com/app/mac/23875/avc1decoder, and x264Encoder 1.2.27 also from MyCometG3, and I put them in my Library/Quicktime folder and restarted Quicktime, but neither solved the problem.  I also tried opening the .mp4 files in MPEG Streamclip (1.9.2), but it says "File open error: unrecognized file type".  When I tell it to "open anyway" it tries and then says "File open error: can't find video or audio tracks".
The indiscriminant installation of additional codecs often creates more problems than it solves owing to the logrithmic increased potential for the introduction of QT codec component conflicts. The normal "rule of thumb" here is to identify a missing codec and to then install only that specific codec component. Even then, there is a possibility that there may be a conflict but at least it is more easily identified so you can better evaluate which of the conflicting codecs to leave installed and which to swap only when needed/required. As to the use of MPEG Streamclip, it basically uses your system's QT component configuration of access of most codecs as opposed to VLC and HandBrake which contain their own, built-in codec support. So if QT is having a problem, it is often likely that MPEG Streamclip will also have problems.
I tried opening one of these .mp4 files in Handbrake (0.9.8) and it was able to open and convert the file to an .mp4 that is then openable in QT 10 with a format of H.264, AAC, and a reduced frame rate of 29.84.  However, this doesn't seem like a good solution because it takes about 2 hours to convert a file with 30 minutes of video.  I just want to be able to trim these big files down to some short video clips that are in an accessible format.
The HandBrake workflow forces a recompressing of the file data which is why it takse so long. That is why I suggested you try deleting any extraneous data tracks found in the source MP4 file container using QT 7 Pro and then use the "Save" or "Save As..." option to re-write the original audio and video data to a new MOV file container which takes much less time.
Am I missing the right codec?  Or, as I'm beginning to wonder, is this format one that is too demanding for OS 10.6.8 and QT 10 and they just cannot handle it no matter what codecs I have on my computer (because of the 60 fps frame rate?  Or is it the subtitle track?).  Or is the solution to upgrade my operating system to Mountain Lion (10.8) and QT 10.2?  My 15" MacBook Pro is about 2 years old with a 2.66 GHz Intel Core i7 and 4 GB of RAM (1067 MHz DDR3).
Probably not. The VLC reported data rate may either indicate the MP4 content is AVCHD/BD sourced or it is reading interlaced content as progressive which I have noted it can do on occasion when I compare the media info as read by various different apps and/or utilities. Since you indicate the file opens in Mountain Lion, my guess would be that your MP4 content is actually AVCHD/BD sourced since such support was only recently added to Mac OS X v10.8 software. As to moving up to Mountain Lion, as always, that is something you would have to evaluate for yourself. For instance, do you require PNG compression for video content? By default you would lose it under Mountain Lion and have to re-enable it manually if needed. Are there other pros and cons that you need to consider before upgrading to Mountain Lion? These are the types of questions and compatibility issues that only you can answer for yourself.