6.0.0 video thumbnailer...

[Maik Qualmann]

Hi Gilles,

great, you are really fast. The QtAV widget does not rotate on its own. I 
added this feature a few days ago, as the orientation of the video in 
DMetadata with your new FFMpeg code was available.

Maik

Am Donnerstag, 8. März 2018, 15:57:48 CET schrieb Gilles Caulier:
> Else, i tested with the collection of video files from GDrive :
> 
> https://drive.google.com/drive/folders/10-SJNtJZZQd_LIchfav-YQ9a-pNsQStT
> 
> The thumbnailer work as expected and there is no problem as QtAv frame
> extractor generate.
> 
> Note : the thumbnails orientation don't need to be changed. Sound like
> ffmpeg autorotate the stream automatically. There are few video taken
> vertically in the collection and without to use exif rotation flag value,
> all is displayed in right direction as well.
> 
> Note2 : The video preview is also auto-rotated by QtAv widget. No need to
> double rotation of video while playing. Just test with video sample to
> reproduce the problem.
> 
> Gilles Caulier
> 
> 2018-03-08 15:51 GMT+01:00 Gilles Caulier <caulier.gilles at gmail.com>:
> > Maik,
> > 
> > The new video thumbnailer code based on ffmpeg is reviewed and optimized,
> > excepted the last deprecated warning messages.
> > 
> > These last one are relevant of change of FFMPEG API. It's not only some
> > method call changes (+arguments). The type of structures have also
> > changed.
> > Typically :
> > 
> > - AVPicture struct must be changed as AVFrame or a utils method from
> > libavutil must be used.
> > 
> > - AVCodecContext struct must be changed as AVCodecParameters.
> > 
> > This must be done before to change deprecated methods. A simple migration
> > of deprecated methods introduce more warnings due to use other internal
> > structures.
> > 
> > The most tedious method to port is avcodec_decode_video2() which must e
> > replaced by 2 calls :  avcodec_send_packet() and avcodec_receive_frame().
> > The last one must be pooled with a loop. It's not simple...
> > 
> > Gilles
> > 
> > 2018-03-06 22:06 GMT+01:00 Gilles Caulier <caulier.gilles at gmail.com>:
> >> No, i use last stable QtAv 1.12.0 from Mageia6...
> >> 
> >> Gilles
> >> 
> >> 2018-03-06 21:20 GMT+01:00 Maik Qualmann <metzpinguin at gmail.com>:
> >>> Gilles,
> >>> 
> >>> do you use QtAV from the git/master? If so, it may be due to a new
> >>> signal in
> >>> the video frame extractor compared to version 1.12. I could fix that.
> >>> 
> >>> Maik
> >>> 
> >>> Am Sonntag, 4. März 2018, 23:00:17 CET schrieb Gilles Caulier:
> >>> > And this line :
> >>> > https://cgit.kde.org/ffmpegthumbs.git/tree/CMakeLists.txt#n16
> >>> > 
> >>> > Gilles
> >>> > 
> >>> > 2018-03-04 22:58 GMT+01:00 Gilles Caulier <caulier.gilles at gmail.com>:
> >>> > > Look this line :
> >>> > > 
> >>> > > https://cgit.kde.org/ffmpegthumbs.git/tree/ffmpegthumbnailer.h#n21
> >>> > > 
> >>> > > Gilles
> >>> > > 
> >>> > > 2018-03-04 19:27 GMT+01:00 Maik Qualmann <metzpinguin at gmail.com>:
> >>> > >> Gilles,
> >>> > >> 
> >>> > >> libffmpegthumbnailer has no KIO dependencies, only C and FFMpeg. Or
> >>> 
> >>> I do
> >>> 
> >>> > >> not
> >>> > >> look right? Does the package exist in your Linux distribution?
> >>> > >> 
> >>> > >> https://github.com/dirkvdb/ffmpegthumbnailer/tree/master/lib
> >>> > >> ffmpegthumbnailer
> >>> > >> 
> >>> > >> Maik
> >>> > >> 
> >>> > >> Am Sonntag, 4. März 2018, 18:56:48 CET schrieb Gilles Caulier:
> >>> > >> > Another one : https://bugs.kde.org/show_bug.cgi?id=387892
> >>> > >> > 
> >>> > >> > not reproducible here, but with FFMPEG, this will kill the bug...
> >>> > >> > 
> >>> > >> > Gilles
> >>> > >> > 
> >>> > >> > 2018-03-04 18:55 GMT+01:00 Gilles Caulier <
> >>> 
> >>> caulier.gilles at gmail.com>:
> >>> > >> > > For me this entry is valid :
> >>> > >> > > 
> >>> > >> > > https://bugs.kde.org/show_bug.cgi?id=390443
> >>> > >> > > 
> >>> > >> > > and we can try to close this file if we use FFMPEG directly to
> >>> > >> 
> >>> > >> generate
> >>> > >> 
> >>> > >> > > thumbnailer...
> >>> > >> > > 
> >>> > >> > > Gilles
> >>> > >> > > 
> >>> > >> > > 2018-03-04 17:49 GMT+01:00 Gilles Caulier <
> >>> 
> >>> caulier.gilles at gmail.com>:
> >>> > >> > >> Hi all,
> >>> > >> > >> 
> >>> > >> > >> Since i written the FFMPEG video metadata parser in 6.0.0
> >>> 
> >>> branch,
> >>> 
> >>> > >> > >> i'm
> >>> > >> > >> trying to register a huge video collection from my host
> >>> 
> >>> computer.
> >>> 
> >>> > >> > >> Here, more than 2500 MKV files are present, plus a lots of
> >>> 
> >>> MP4, MOV,
> >>> 
> >>> > >> and
> >>> > >> 
> >>> > >> > >> another media taken with cellular and camera.
> >>> > >> > >> 
> >>> > >> > >> The registration have been very fast. 2500 file parsed in 2
> >>> 
> >>> minutes
> >>> 
> >>> > >> and
> >>> > >> 
> >>> > >> > >> ready to use. System has SSD, Sqlite, 8 cores, and 32Gb of
> >>> 
> >>> RAM. No
> >>> 
> >>> > >> crash
> >>> > >> 
> >>> > >> > >> all work fine... excepted... the video thumbnails.
> >>> > >> > >> 
> >>> > >> > >> I facing random dysfunctions with video files. Sometime thumbs
> >>> 
> >>> are
> >>> 
> >>> > >> there,
> >>> > >> 
> >>> > >> > >> sometime not. Using F5 always give a different results until i
> >>> 
> >>> try
> >>> 
> >>> > >> > >> to
> >>> > >> > >> insist and i can see the DB locked and revival...
> >>> > >> > >> 
> >>> > >> > >> The video thumbnailer is based on QtAV frame extractor. My
> >>> 
> >>> QtAV is
> >>> 
> >>> > >> last
> >>> > >> 
> >>> > >> > >> stable 1.12.0. I suspect a bug somewhere in QtAV, as i can see
> >>> > >> > >> thumbnailer
> >>> > >> > >> code including a lots of mutex to prevent concurrency.
> >>> > >> > >> 
> >>> > >> > >> This is typically abnormal. FFMPEG API is re-entrant as i
> >>> 
> >>> checked
> >>> 
> >>> > >> with
> >>> > >> 
> >>> > >> > >> the multi-threaded metadata parser unit test.
> >>> > >> > >> 
> >>> > >> > >> As we depend now directly of FFMPEG API, I propose to rewrite
> >>> 
> >>> the
> >>> 
> >>> > >> video
> >>> > >> 
> >>> > >> > >> thumbnailer with libav C function.
> >>> > >> > >> 
> >>> > >> > >> We have code ready to use with ffmpeg API here :
> >>> > >> > >> 
> >>> > >> > >> https://cgit.kde.org/ffmpegthumbs.git/tree/
> >>> > >> > >> 
> >>> > >> > >> Your viewpoint ?
> >>> > >> > >> 
> >>> > >> > >> Gilles