[FFmpeg-user] How to compress .MOV file compatible to Canon camera

[Ulf Zibis]

Am 16.03.20 um 01:43 schrieb Ulf Zibis:
>
> Am 14.03.20 um 21:08 schrieb Carl Eugen Hoyos:
>> Am Sa., 14. März 2020 um 20:39 Uhr schrieb Ted Park <kumowoon1025 at gmail.com>:
>>
>>>>>>> Did you already test the following?
>>>>>>> $ ffmpeg -i MVI_1324.MOV -acodec copy -vcodec copy out.mov
>>>>>> Then the codec time base remains
>>>>> Of course.
>>>>>
>>>>> The question is if the file is still playable after remuxing.
>>>> It is no more playable on the camera.
>>>> It's about 100 kB smaller then the original with 84 MB.
>>> Maybe you should consider the possibility that it isn’t a technical limitation of the decoder capability but something else introduced by proprietary metadata or implementation detail.
>>>
>>> There’s a huge user data box in the moov, upon a quick glance it has the camera model, firmware version, etc. I have to imagine it is used somehow.
>> Same question:
>> Is the (original) file still playable if you edit this atom?
>
> I now inserted the following:
> 1. "CEAP" to ftyp (0x18 instead 0x14 bytes)
> 2. moov atom with qt-faststart
> 2. udta atom from original at the start of moov atom (increases it from 0x1340E to 0x1344A)
> Result:
> Instead of a big "?" I now see a the preview picture on the camera. Unfortunately I still can't play the video because of "Not identified Picture".
> So we are a little step closer to the solution.
> Any additional ideas?
> Yes, it would be a great help of a good tool to show and edit other atoms.
> Which tool could be this?
> Which ffmpeg loglevel command would show the atoms, even with less nice format?
As I see from the qt-faststart output, I see, that there are some other atoms patched:
$ qt-faststart MVI_1324_copy_git.mov MVI_1324_copy_git.MOV
ftyp          0 20
wide         20 8
mdat         28 84830220
moov   84830248 13326
  patching stco atom...
  patching stco atom...
  writing ftyp atom...
  writing moov atom...
  copying rest of file...

So maybe I have to patch them again after inserting the udta atom, but how?

-Ulf