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GetID3 - Bloc informations de fichiers
9 avril 2013, par
Mis à jour : Mai 2013
Langue : français
Type : Image
Autres articles (34)
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La file d’attente de SPIPmotion
28 novembre 2010, parUne file d’attente stockée dans la base de donnée
Lors de son installation, SPIPmotion crée une nouvelle table dans la base de donnée intitulée spip_spipmotion_attentes.
Cette nouvelle table est constituée des champs suivants : id_spipmotion_attente, l’identifiant numérique unique de la tâche à traiter ; id_document, l’identifiant numérique du document original à encoder ; id_objet l’identifiant unique de l’objet auquel le document encodé devra être attaché automatiquement ; objet, le type d’objet auquel (...) -
Websites made with MediaSPIP
2 mai 2011, parThis page lists some websites based on MediaSPIP.
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Des sites réalisés avec MediaSPIP
2 mai 2011, parCette page présente quelques-uns des sites fonctionnant sous MediaSPIP.
Vous pouvez bien entendu ajouter le votre grâce au formulaire en bas de page.
Sur d’autres sites (8343)
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FFMPEG : Use expression calculated from timestamp to drawtext [closed]
26 décembre 2020, par NicolasVUsing ffmpeg and draw text, I need write on the video something like that :


text=1+floor(BPM * mod(1000*t-StartCounter ;480000/BPM)/60000).


I don't know if I need use PTS or t.


StartCounter would be a variable in milliseconds, the text would appear at this point.


BPM is an integer variable between 100 and 180.


I would draw for instance with StartCounter = 3256 and BPM = 120.


Any help appreciated, thanks


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Best way to diagnose VideoCapture not opening the rtmp stream
8 janvier 2021, par Greg0ryI am pulling my hair off for a few days and I'm out of ideas.


I have two rtmp streams


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- first stream is transcoded directly by myself (I use ffmpeg to transcode) and then I attach to that stream with opencv - VideoCapture can open the stream with no problem
- second stream is transcoded by 3rd party system (this system captures video through WebRTC and then encodes to h264) - this stream cannot be opened by VideCapture no matter what I do






I can attach with pure ffmpeg to that dodgy stream and I can restream - but this is not ideal as introduces extra network traffic and latency.


I was playing with
OPENCV_FFMPEG_CAPTURE_OPTIONS
environmental variable (I was trying to remove audio stream, change the video codec, playing with rtmp options like thisOPENCV_FFMPEG_CAPTURE_OPTIONS="loglevel;debug" python my_script.py
) - no joy

So I figured I am trying to solve this problem from wrong end. I should somehow collect underlying ffmpeg logs that should be available when calling VideoCapture. So I tried to set
OPENCV_FFMPEG_CAPTURE_OPTIONS="v;debug"
but I can see no ffmpeg output when calling VideoCapture.

This is very simple python3 script I was using during tests :


import cv2 as cv
dodgy_cap = cv.VideoCapture()
dodgy_cap.open('rtmp://my_local_ip_address/rtmp/dodgy_stream_name')
print(dodgy_cap.isOpened()) # always returns False
healthy_cap = cv.VideoCapture()
healthy_cap.open('rtmp://my_local_ip_address/rtmp/healthy_stream_name')
print(healthy_cap.isOpened()) # always returns True



I collected information about both streams with ffprobe, but even though they look different I cannot see what would be the difference that prevents opencv from opening VideoCapture for dodgy stream..


This is a fragment from (very) verbose log for healthy stream :


RTMP_ClientPacket, received: notify 254 bytes 
(object begin) 
Property: 
Property: 
(object begin) 
Property: 
Property: 
Property: 
Property: 
Property: 
Property: 
Property: 
Property: 
Property: 
Property: 
(object end) 
(object end) 
Metadata:
 duration 0.00
 width 2048.00
 height 1536.00
 videodatarate 0.00
 framerate 6.00
 videocodecid 7.00
 title Session streamed by "preview"
 comment h264Preview_01_main
 encoder Lavf58.20.100
 filesize 0.00

(... raw network packets ...)

Input #0, flv, from 'rtmp://my_local_ip_address/rtmp/healthy_stream_name':
 Metadata:
 title : Session streamed by "preview"
 comment : h264Preview_01_main
 encoder : Lavf58.20.100
 Duration: 00:00:00.00, start: 159.743000, bitrate: N/A
 Stream #0:0, 41, 1/1000: Video: h264 (High), 1 reference frame, yuv420p(progressive), 2048x1536, 0/1, 6 fps, 6 tbr, 1k tbn




And this is the fragment for dodgy stream :


RTMP_ClientPacket, received: notify 205 bytes 
(object begin) 
Property: 
(object begin) 
Property: 
Property: 
Property: 
Property: 
Property: 
Property: 
Property: 
Property: 
Property: 
(object end) 
(object end) 
RTMP_ReadPacket: fd=3 

(... raw network packets ...)

Input #0, flv, from 'rtmp://my_local_ip_address/rtmp/dodgy_stream_name':
 Duration: N/A, start: 4511.449000, bitrate: N/A
 Stream #0:0, 41, 1/1000: Video: h264 (High), 1 reference frame, yuv420p(progressive, left), 640x480, 0/1, 15.17 fps, 15.08 tbr, 1k tbn, 30 tbc
 Stream #0:1, 124, 1/1000: Audio: aac (LC), 48000 Hz, mono, fltp




Both streams don't require any authentication (they are not exposed to the outside world)


Dodgy stream contains audio but I don't think it is source of problem as I was able to connect to other healthy rtmp streams that contained audio..


I have no more ideas how can I debug this problem, please help..



I found in VideoCap documentation that I can enable exception mode, however it did not help much (it says where it failed but it does not say why) :


>>> dodgy_stream = cv.VideoCapture()
>>> dodgy_stream.setExceptionMode(True)
>>> dodgy_stream.open("rtmp://my_local_ip_address/rtmp/dodgy_stream_name")
Traceback (most recent call last):
 File "<stdin>", line 1, in <module>
cv2.error: OpenCV(4.5.0) /tmp/pip-req-build-s_nildlw/opencv/modules/videoio/src/cap.cpp:177: error: (-2:Unspecified error) could not open 'rtmp://my_local_ip_address/rtmp/dodgy_stream_name' in function 'open'
</module></stdin>


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How to use web analytics to acquire new customers
2 septembre 2020, par Joselyn Khor — Analytics Tips, Marketing