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Publier sur MédiaSpip
13 juin 2013Puis-je poster des contenus à partir d’une tablette Ipad ?
Oui, si votre Médiaspip installé est à la version 0.2 ou supérieure. Contacter au besoin l’administrateur de votre MédiaSpip pour le savoir -
Création définitive du canal
12 mars 2010, parLorsque votre demande est validée, vous pouvez alors procéder à la création proprement dite du canal. Chaque canal est un site à part entière placé sous votre responsabilité. Les administrateurs de la plateforme n’y ont aucun accès.
A la validation, vous recevez un email vous invitant donc à créer votre canal.
Pour ce faire il vous suffit de vous rendre à son adresse, dans notre exemple "http://votre_sous_domaine.mediaspip.net".
A ce moment là un mot de passe vous est demandé, il vous suffit d’y (...) -
Les tâches Cron régulières de la ferme
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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