[FFmpeg-user] Three questions about quicktime: The encoder ID and the timecode flag

[Hadmut Danisch]

Hi,


I'm currently trying to solve this problem: I have a Blackmagic Design 
Hyperdeck Studio Mini device, which is both a recorder and player for 
professional video (TV studio). But impolite, as the device is, it is 
playing only those videos it has recorded itself, and completely 
ignoring other videos I've put on the memory cards in order to have them 
played. Other owners of these devices do have the same problems, there's 
currently no solution found in the Blackmagic forum.

Therefore I am trying to mimic the videos made by this device as close 
as possible with ffmpeg. The device produces Quicktime Videos, and most 
of the settings I am able to generate with ffmpeg, but there's still 
differences I haven't found solutions for.

The device records Quicktime videos, and I'm currently using ffmpeg options

-r 50:1 -vf scale=1920:1080  -pix_fmt yuv420p -c:v prores_ks -profile:v 
2 -c:a pcm_s24le


Three of them are:


1. mediainfo reveals a difference in the Container ID.

For the video recorded with the device it reports in the General section

Format                                   : MPEG-4
Format profile                           : QuickTime
Codec ID                                 : qt   2005.03 (qt  )

while for the ffmpeg-generated it says

Format                                   : MPEG-4
Format profile                           : QuickTime
Codec ID                                 : qt   0000.02 (qt  )

Note the difference  2005.03 vs. 0000.02

Which options would change this ID?


2. qtinfo (tool from quicktime libraries) reveals a difference in the 
frame rate:


Blackmagic:

rate 50.000000 [50:1] constant

ffmpeg:

rate 50.000000 [12800:256] constant



3. qtinfo finds another difference, it's in the time code:


Blackmagic:

     Timecodes available (flags: 00000002, rate: 50)

ffmpeg:

     Timecodes available (flags: 00000000, rate: 50)


How can I set this flag? (And what's its meaning?)



Hints highly appreciated.


Thanks and regards

Hadmut