Bug 374453

First, digiKam do not use Exiftool to extract metadata. It use Exiv2 instead.

Second, Exiv2 0.26 support better video metadata. We include this version of library (not yet released), in universal Linux AppImage bundle. Please try with this digiKam 5.4.0 pre-release available here :

https://drive.google.com/drive/folders/0BzeiVr-byqt5Y0tIRWVWelRJenM

Gilles Caulier

Hello Gilles,

First, thanks for your quick answer.

I haven't the required knowledge to judge which is the better API to process metadata: exiftool example was just to identify which component is responsible of this display.

I'll give you a feedback with the 5.4 version.

Regards

Confirmed on 5.4.0. For all mp4 files digiKam used a file modification date instead of any content create date from metadata. Looks like exiv2 does not read any metadata from mp4 files yet.

I am wondering if this might help:
https://discuss.pixls.us/t/organize-images-videos-in-folders-by-month-date-taken/3156/10?u=andrius
There is a link to a piece of code of Rapid Photo Downloader responsible for reading video files' creation date in the post. I tested it on my machine and it worked well, all video files went to correct date folders

Mediainfo reads the date well:

mediainfo FILE.mp4 | grep "Encoded date" | head -n 1

Example output:
Encoded date : UTC 2012-01-08 11:16:19

Hello Gilles,

This message also applicable to:
https://bugs.kde.org/show_bug.cgi?id=377072
https://bugs.kde.org/show_bug.cgi?id=377177

It turned out that ffmpeg is already able to read a lot of metadata we could use.

Here is an output of an ffmeg -i command on a sample file:
---
Input #0, mov,mp4,m4a,3gp,3g2,mj2, from '/mnt/data/FamilyPictures/2016/2016-10/20161008/20161007_190516.mp4':
  Metadata:
    major_brand     : mp42
    minor_version   : 0
    compatible_brands: isommp42
    creation_time   : 2016-10-08T01:10:04.000000Z
    location        : +50.8893-114.0159/
    location-eng    : +50.8893-114.0159/
    com.android.version: 6.0.1
  Duration: 00:00:43.20, start: 0.000000, bitrate: 16947 kb/s
    Stream #0:0(eng): Video: h264 (High) (avc1 / 0x31637661), yuv420p, 1920x1080, 16876 kb/s, 29.78 fps, 29.92 tbr, 90k tbn, 180k tbc (default)
    Metadata:
      rotate          : 90
      creation_time   : 2016-10-08T01:10:04.000000Z
      handler_name    : VideoHandle
    Side data:
      displaymatrix: rotation of -90.00 degrees
    Stream #0:1(eng): Audio: aac (LC) (mp4a / 0x6134706D), 48000 Hz, stereo, fltp, 256 kb/s (default)
    Metadata:
      creation_time   : 2016-10-08T01:10:04.000000Z
      handler_name    : SoundHandle
---

Reading just these three fields

creation_time   : 2016-10-08T01:10:04.000000Z
location        : +50.8893-114.0159/
rotate          : 90 (or displaymatrix: rotation of -90.00 degrees)

will allow digiKam to:

1. Import video files in correct folders, rename them correctly on import
2. Show video files in chronological order when sort by date
3. Show video files on the map, add GPS information to the database
4. Preview video correctly per the rotation tag, create correct video thumbnails

Is that possible to add the support of this on your roadmap? Let me know your thoughts.

https://github.com/wang-bin/QtAV/issues/820#issuecomment-287545695

yes, we can do it through QtAV.

Try to use stand alone QtAv Player. Load a video and go to Info pannel. These ffmpeg metadata are there. So i'm sure more and less that QtAV can provide all these kind of data to client application as digiKam, without to use directly ffmpeg (and add direct ffpmeg dependencies to digiKam.

Gilles Caulier

(In reply to caulier.gilles from comment #7)
> yes, we can do it through QtAV.
> 
> Try to use stand alone QtAv Player. Load a video and go to Info pannel.
> These ffmpeg metadata are there. So i'm sure more and less that QtAV can
> provide all these kind of data to client application as digiKam, without to
> use directly ffmpeg (and add direct ffpmeg dependencies to digiKam.
> 
> Gilles Caulier

It can write too. I just wrote GPS location into mp4 file using this command
ffmpeg -i inputfile -metadata location="+50.8893-114.0159/" outputfile

Very interesting. Do you know if there is already somewhere a c++ interface to ffmpeg to read/write metadata on video ?

(In reply to caulier.gilles from comment #9)
> Very interesting. Do you know if there is already somewhere a c++ interface
> to ffmpeg to read/write metadata on video ?

Is this close to what you are looking for?

https://ffmpeg.org/doxygen/2.0/doc_2examples_2metadata_8c-example.html

With 6.0.0, we have now a FFMpeg low level metadata parser based on libav C API
for video files database registration.

The Exiv2 video support is not used anymore as this code is buggous and nobody
sound motivated in Exiv2 to finalize the code.

The original post for this file must be fixed now and video metadata support
with ffmpeg must be enough to populate database entries.

Gilles Caulier