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Géodiversité
9 septembre 2011, par ,
Mis à jour : Août 2018
Langue : français
Type : Texte
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USGS Real-time Earthquakes
8 septembre 2011, par
Mis à jour : Septembre 2011
Langue : français
Type : Texte
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SWFUpload Process
6 septembre 2011, par
Mis à jour : Septembre 2011
Langue : français
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La conservation du net art au musée. Les stratégies à l’œuvre
26 mai 2011
Mis à jour : Juillet 2013
Langue : français
Type : Texte
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Podcasting Legal guide
16 mai 2011, par
Mis à jour : Mai 2011
Langue : English
Type : Texte
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Creativecommons informational flyer
16 mai 2011, par
Mis à jour : Juillet 2013
Langue : English
Type : Texte
Autres articles (74)
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Le profil des utilisateurs
12 avril 2011, parChaque utilisateur dispose d’une page de profil lui permettant de modifier ses informations personnelle. Dans le menu de haut de page par défaut, un élément de menu est automatiquement créé à l’initialisation de MediaSPIP, visible uniquement si le visiteur est identifié sur le site.
L’utilisateur a accès à la modification de profil depuis sa page auteur, un lien dans la navigation "Modifier votre profil" est (...) -
Configurer la prise en compte des langues
15 novembre 2010, parAccéder à la configuration et ajouter des langues prises en compte
Afin de configurer la prise en compte de nouvelles langues, il est nécessaire de se rendre dans la partie "Administrer" du site.
De là, dans le menu de navigation, vous pouvez accéder à une partie "Gestion des langues" permettant d’activer la prise en compte de nouvelles langues.
Chaque nouvelle langue ajoutée reste désactivable tant qu’aucun objet n’est créé dans cette langue. Dans ce cas, elle devient grisée dans la configuration et (...) -
Les autorisations surchargées par les plugins
27 avril 2010, parMediaspip core
autoriser_auteur_modifier() afin que les visiteurs soient capables de modifier leurs informations sur la page d’auteurs
Sur d’autres sites (12116)
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Can't playback huge video which was uploaded to google storage. I Get Error : Unable to retrieve manifest /stream.m3u8 -Error : Could not retrieve file
18 juillet 2022, par Dmytro PetskovychI upload file to google storage using "@ffmpeg-installer/ffmpeg" and @google-cloud/storage in my node.js App.
Step 1. file uploading to fs is in child processes - one process for each type of resolution (totaly six).
step 2. encription (converting to stream)
step 3. upload to google storage


This way is working fine only with small file. When i upload large file I Get server Error : Unable to retrieve manifest /stream.m3u8 or Unable to retrieve .


It seems that not all splits are uploaded to the cloud. but i checked they are there.


I am currently using "Upload a directory to a bucket" in order to send the video from the client to the Google Cloud Storage bucket.


when I upload video, actually I upload six videos, one for each type resolution


for example when I upload video with duration one hour it split on chunk and totally I get more three thousands files.


not all of this files are accessible when i try playback video. that's why I can't play video in all types of resolution and get error like


maybe someone had the similar problem and helps fix it
.
i have no idea why i get that behavior only with huge file


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Mixing audio stream into video stream using ffmpeg while retaining original audio from the video stream as background [duplicate]
18 mars 2020, par Core7sI have a live video stream and a live audio stream. The audio stream has to get mixed into the video stream and the resulting stream is pushed to YouTube. I have this working
ffmpeg -i videostream -i audiostream -map 0:1 -map 1:0 -shortest -c:a copy -c:v copy -f flv streamout-youtube;
However I am losing the original audio in thevideostream
. I want to have the original audio playing at maybe 20% of the original volume.
I looked around a lot and found maybe I can modify the above command to use-filter_complex
to getffmpeg -i videostream -i audiostream -filter_complex "volume=0.2" -map 0:1 -map 1:0 -shortest -c:a copy -c:v copy -f flv streamout-youtube;
However, when I add the
-filter_complex
option, the stream goes dead meaning it doesn’t get pushed to youtube anymore. I have verified the stream keys are correct. This seems to be a rather simple thing but I can’t put my finger on what’s wrong.I am using rtmp module of nginx to receive, mix and push out streams.
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OpenCV Encoding to H264 changing original RGB pixel values for gray images
13 janvier 2020, par CristoJVI have the following issue :
I’m creating a uniform gray color video (for testing) using OpenCV VideoWriter. The output video will reproduce a constant image where all the pixels must have the same value x (25, 51, 76,... and so on).
When I generate the video using MJPG Encoder :vw = cv2.VideoWriter('./videos/input/gray1.mp4',
cv2.VideoWriter_fourcc(*'MJPG'),
fps,(resolution[1],resolution[0]))and read the output using the VideoCapture class, everything just works fine. I got a frame array with all pixel values set to (25,51,76 and so on).
However when I generate the video using HEV1 (H.265) or also H264 :vw = cv2.VideoWriter('./videos/input/gray1.mp4',
cv2.VideoWriter_fourcc(*'HEV1'),
fps,(resolution[1],resolution[0]))I run into the following issue. The frame I got in BGR format follows the next configuration :
- The blue channel value is the expected value (x) minus 4 (25-4=21, 51-4=47, 76-4=72, and so on).
- The green channel is the expected value (x) minus 1 (25-1=24, 51-1=50, 76-1=75).
- The red channel is the expected value (x) minus 3 (25-3=22, 51-3=48, 76-3=73).
Notice that the value is reduced with a constant value of 4,1,3, independently of the pixel value (so there is a constant effect).
What I could explain is a pixel value dependable feature, instead of a fixed one.
What is worse is that if I choose to generate a video with frames consisting in every color (pixel values [255 0 0],[0 255 0] and [0 0 255]) I get the corresponding outputs values ([251 0 0],[0 254 0] and [0 0 252])
I though that this relation was related to the grayscale Y value, where :Y = 76/256 * RED + 150/256 * GREEN + 29/256 * BLUE
But this coefficients are not related with the output obtained. Maybe the problem is the reading with VideoCapture ?
EDIT :
In case that I want to have the same output value for the pixels (Ej : [10,10,10] experimentally I have to create a img where the red and blue channel has the green channel value plus 2 :value = 10
img = np.zeros((resolution[0],resolution[1],3),dtype=np.uint8)+value
img[:,:,2]=img[:,:,2]+2
img[:,:,1]=img[:,:,1]+0
img[:,:,0]=img[:,:,0]+2Anyone has experience this issue ? It is related to the encoding process or just that OpenCV treats the image differently, prior encoding, depending on the fourcc parameter value ?