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• Anomalie #4799 (Fermé) : Validité du RSS

  7 juillet 2021, par b b

  C’est intégré, je ferme car amha le point sur les multiples enclosures est négligeable, cf :

  According to the RSS Advisory Board’s Best Practices Profile, support for the enclosure element in RSS software varies significantly because of disagreement over whether the specification permits more than one enclosure per item. Although the author intended to permit no more than one enclosure in each item, this limit is not explicit in the specification.

  For best support in the widest number of aggregators, an item should not contain more than one enclosure.
  Meanwhile, be aware that multiple-enclosure support varies widely from tool tool to tool, and therefore should be avoided if at all possible.

• AWS EC2 and OpenCV with UDP consumer

  22 juillet 2021, par NoobZik

  I have two EC2

  


  

  • A That grabs the video feed from Amazon Kinesis Video to send it into via UDP to B

  


  • B the consumer which it will grab the UDP feed from the A

  


  


  While debugging my opencv not grabbing the UDP feed, I suspect something is wrong with ffpmeg, so I am going to make sure that ffplay can read packets sent from A.

  


  Now when I try to read udp packets with ffplay {adress-ip-with-port}I have the following error :

  


  Could not initialize SDL - No available video device
(Did you set the DISPLAY variable?)


  


  How do I fix this one since there is no display on EC2.

  


  Also if it can help, this is my code for the consumer part

  


   Create your views here.
from django.http import HttpResponse
from django.template import loader
from django.shortcuts import render
# from .models import Vehicule
import cv2
import threading
from django.views.decorators import gzip
from django.http import StreamingHttpResponse


@gzip.gzip_page
def webcam(request):
    try:
        cam = VideoCamera()
        return StreamingHttpResponse(gen(cam), content_type="multipart/x-mixed-replace;boundary=frame")
    except:
        pass
    return render(request, 'vebcam.html')

#capture video
class VideoCamera(object):
    def __init__(self):
        self.video = cv2.VideoCapture('udp://172.31.57.243:55055', cv2.CAP_FFMPEG)
        (self.grabbed, self.frame) = self.video.read()
        threading.Thread(target=self.update, args=()).start()

    def __del__(self):
        self.video.release()

    def get_frame(self):
        image = self.frame
        _, jpeg = cv2.imencode('.jpg', image)
        return jpeg.tobytes()

    def update(self):
        while True:
            (self.grabbed, self.frame) = self.video.read()

def gen(camera):
    while True:
        frame = camera.get_frame()
        yield (b'--frame\r\n'b'Content-Type: image/jpeg\r\n\r\n' + frame + b'\r\n\r\n')


  


  It runs fine on local but not on EC2

  


  This is the log that led me to check ffplay

  


  Traceback (most recent call last):
  File "/usr/lib/python3.8/wsgiref/handlers.py", line 138, in run
    self.finish_response()
  File "/usr/lib/python3.8/wsgiref/handlers.py", line 183, in finish_response
    for data in self.result:
  File "/home/ubuntu/.local/lib/python3.8/site-packages/django/utils/text.py", line 304, in compress_sequence
    for item in sequence:
  File "/home/ubuntu/site/mysite/mysite/views.py", line 42, in gen
    frame = camera.get_frame()
  File "/home/ubuntu/site/mysite/mysite/views.py", line 33, in get_frame
    _, jpeg = cv2.imencode('.jpg', image)
cv2.error: OpenCV(4.5.3) /tmp/pip-req-build-xw6jtoah/opencv/modules/imgcodecs/src/loadsave.cpp:978: error: (-215:Assertion failed) !image.empty() in function 'imencode'


  


• FFMPEG seems to not be reading files from .txt file [closed]

  15 août 2021, par user3266908

  I have the following command

  


  ffmpeg -f concat -safe 0 -i C:\location1\location2\01\video.txt  -f  concat  -safe 0 -i C:\lcation2\location2\01\image.txt -filter_complex_script C:\location1\location2\01\script.txt C:\PollyBot\audio\morning.mp4


  


  the video.txt , image.txt and the script.txt reads as follow. Side note the script.txt file applies a filter.

  


  video.txt
file 'c:\videos\video.mp4'


images.txt
file 'c:\images\image01.png'
file 'c:\images\image02.png'

script
[0:V]scale=1080:-1,pad=0:1920:0:(oh-ih)/2[vid];
[vid][1:0]overlay=enable='between(t,10,15)'[i1];
[i1][1:1]overlay=enable='between(t,20,35)'


  


  What happens is that the scale of the video is scaled but streams for the images only every displays 1 images and never returns a stream for the second image. I have tried different versions of ffmpeg, removing the overlay and just forcibly calling the second stream with out it being listed but nothing works. I also noticed that this issue is present in the other .txt files as well. It seems like ffmpeg only reads the first item in the .txt file and ignores everything else. this issue is repeatable in the other files as well. Just one video, the first is seen. I'm new to FFMPEG so any pointers is welcome. Keep in mind that I'm doing this all from the windows machine and if I run the command with just one image/overlay files it runs with out issue.

  


  

  


  To me it looks that something is wrong with my .txt file and that it is unable to read anything past the first line since if I'm just overlaying one item it works just fine.