Unable to load movies to Windows iTunes/iPad

Windows 7 running in a VirtualBox vm on a Fedora-20 Linux Intel x86-64 system.

On the Windows vm:

iTunes version 12.2.1.16

Quicktime 7.7.7

iPad-2 IOS 8.4 connected by USB

I have a few movies on this iPad added thorugh iTunes about three years ago using the then-current version of iTunes on a Windows-XP VM that no longer exists. I would like to add a few more Videos for entertainment on long flights. I have several videos that I would like to add, but the current version of iTunes silently refuses to do anything with the files. File->Add File, File->add folder, drag-n-drop from the file browser, none work. iTunes just silently ignores the attempted input.

I have checked the permissions as in another post on this forum and it appears that the permissions on iTunes are correct. iTunes and Quicktime were recently installed with no options or changes to the defaults.

The Videos play correctly in Quicktime.

The iPad is recognised and I can extract my old videos to a folder using File->Library->export Library.

The Videos are created on Linux using ffmpeg.

ffprobe on a representative video shows:

Input #0, mov,mp4,m4a,3gp,3g2,mj2, from 'x.mp4':

Metadata:

major_brand : isom

minor_version : 512

compatible_brands: isomiso2avc1mp41

encoder : Lavf53.32.100

Duration: 01:42:39.94, start: 0.000000, bitrate: 1198 kb/s

Stream #0:0(und): Video: h264 (High) (avc1 / 0x31637661), yuv420p, 720x480 [SAR 8:9 DAR 4:3], 1063 kb/s, 30 fps, 30 tbr, 30 tbn, 60 tbc (default)

Metadata:

handler_name : VideoHandler

Stream #0:1(und): Audio: aac (mp4a / 0x6134706D), 48000 Hz, stereo, fltp, 126 kb/s (default)

Metadata:

handler_name : SoundHandler

The h.264 codec seems to be right and the aac audio codec also seems to meet the required specs as I read the Apple desired formats.

Googling shows that lots of folks have this problem of iTunes ignoring a video addition. The problem is vaguely described as "Apple only wants specific mp4 formats" but the only solution given is "load this random video transcriber, transcribe the movie and everything will work." No one seems to have any information on what the actual problem is with the unusable .mp4s. I already have ffmpeg. I just am out of ideas on what to tell it for a proper transcription.

So.

Does anyone know what the actual flaw in the ffmpeg transcribed videos might be? Does iTunes or the iPad requires some special bit set somewhere?

Does anyone know how to enable more verbose errors messages or logging in iTunes to get a bit more information about why it silently ignores these files?

Can I provide any additional information that might help solve the problem.

Thanks,

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