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Autres articles (94)
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MediaSPIP 0.1 Beta version
25 avril 2011, parMediaSPIP 0.1 beta is the first version of MediaSPIP proclaimed as "usable".
The zip file provided here only contains the sources of MediaSPIP in its standalone version.
To get a working installation, you must manually install all-software dependencies on the server.
If you want to use this archive for an installation in "farm mode", you will also need to proceed to other manual (...) -
Multilang : améliorer l’interface pour les blocs multilingues
18 février 2011, parMultilang est un plugin supplémentaire qui n’est pas activé par défaut lors de l’initialisation de MediaSPIP.
Après son activation, une préconfiguration est mise en place automatiquement par MediaSPIP init permettant à la nouvelle fonctionnalité d’être automatiquement opérationnelle. Il n’est donc pas obligatoire de passer par une étape de configuration pour cela. -
Gestion générale des documents
13 mai 2011, parMédiaSPIP ne modifie jamais le document original mis en ligne.
Pour chaque document mis en ligne il effectue deux opérations successives : la création d’une version supplémentaire qui peut être facilement consultée en ligne tout en laissant l’original téléchargeable dans le cas où le document original ne peut être lu dans un navigateur Internet ; la récupération des métadonnées du document original pour illustrer textuellement le fichier ;
Les tableaux ci-dessous expliquent ce que peut faire MédiaSPIP (...)
Sur d’autres sites (10231)
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avcodec/nvenc : add rate control option
25 mai 2016, par Andrey Turkin -
Revision a721e5cb0f : Merge "Build / make problem" into experimental
5 novembre 2012, par Yaowu XuMerge "Build / make problem" into experimental
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problem with changing the frames in an video with opencv
5 septembre 2023, par AvizipiI have a code that runs in the last few months without any problem. The code shows an image from a video with extra data from the relevant db. using the keyboard you can jump around some frames and get better insights. However, in the last week changing the frame of the video stopped working.


I built a small script that show the problem.


import cv2

vid_cap_reader_path = "vid_230830_122746_C.avi"
cap_rgb = cv2.VideoCapture(vid_cap_reader_path)

k = 0
while 1:
 if k == ord("q"):
 break
 if k == ord("b"):
 before = cap_rgb.get(cv2.CAP_PROP_POS_FRAMES)
 cap_rgb.set(cv2.CAP_PROP_POS_FRAMES, before + 30.0)
 after = cap_rgb.get(cv2.CAP_PROP_POS_FRAMES)
 print(f"before = {before} after = {after}")
 ret, img = cap_rgb.read()
 if ret:
 cv2.imshow("bla", img)
 k = cv2.waitKey(0)
 else:
 break


This is what is printed to the terminal :


[mpeg4 @ 0x1d87400] warning: first frame is no keyframe
before = 36.0 after = 0.0
before = 67.0 after = 0.0
[mpeg4 @ 0x1d87400] warning: first frame is no keyframe
before = 40.0 after = 0.0
[mpeg4 @ 0x1d87400] warning: first frame is no keyframe


The video itself doesn't "jump" for the next frame as expected and also most of the properties that opencv have return 0. I tested also
CAP_PROP_FRAME_COUNT, andCAP_PROP_POS_MSECwithout any lack, although the msec flag did give non-zero results which make no sense.

It is also important to mention that I am building this application in a docker file and I am not using a specific version for my requirements. The tests here are with
opencv-python==4.7.0.68. Also, the videos are working fine while playing them on VLC.

I was looking around the net for a similar problem from the recent time and didn't find much except this github issue that may be similar. I started to downgrade opencv one by one without any luck.


Maybe someone here can help with this issue, or give me a lead to doing something different.


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