
Recherche avancée
Autres articles (98)
-
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 (...) -
Installation en mode standalone
4 février 2011, parL’installation de la distribution MediaSPIP se fait en plusieurs étapes : la récupération des fichiers nécessaires. À ce moment là deux méthodes sont possibles : en installant l’archive ZIP contenant l’ensemble de la distribution ; via SVN en récupérant les sources de chaque modules séparément ; la préconfiguration ; l’installation définitive ;
[mediaspip_zip]Installation de l’archive ZIP de MediaSPIP
Ce mode d’installation est la méthode la plus simple afin d’installer l’ensemble de la distribution (...) -
Possibilité de déploiement en ferme
12 avril 2011, parMediaSPIP peut être installé comme une ferme, avec un seul "noyau" hébergé sur un serveur dédié et utilisé par une multitude de sites différents.
Cela permet, par exemple : de pouvoir partager les frais de mise en œuvre entre plusieurs projets / individus ; de pouvoir déployer rapidement une multitude de sites uniques ; d’éviter d’avoir à mettre l’ensemble des créations dans un fourre-tout numérique comme c’est le cas pour les grandes plate-formes tout public disséminées sur le (...)
Sur d’autres sites (7643)
-
moviepy black border around png when compositing into an MP4
27 août 2022, par OneWorldcompositing a png into an MP4 video creates a black border around the edge.


This is using moviepy 1.0.0


Code below reproduces the MP4 with the attached red text png.




import numpy as np
import moviepy.editor as mped
def composite_txtpng_on_colour():
 bg_color = mped.ColorClip(size=[400, 300], color=np.array([0, 255, 0]).astype(np.uint8),
 duration=2).set_position((0, 0))
 text_png_postition = [5, 5]
 text_png = mped.ImageClip("./txtpng.png", duration=3).set_position((text_png_postition))

 canvas_size = bg_color.size
 stacked_clips = mped.CompositeVideoClip([bg_color, text_png], size=canvas_size).set_duration(2)
 stacked_clips.write_videofile('text_with_black_border_video.mp4', fps=24)

composite_txtpng_on_colour()



The result is an MP4 that can be played in VLC player. A screenshot of the black edge can be seen below :-




Any suggestions to remove the black borders would be much appreciated.


Update : It looks like moviepy does a blit instead of alpha compositing.


def blit(im1, im2, pos=None, mask=None, ismask=False):
 """ Blit an image over another. Blits ``im1`` on ``im2`` as position ``pos=(x,y)``, using the
 ``mask`` if provided. If ``im1`` and ``im2`` are mask pictures
 (2D float arrays) then ``ismask`` must be ``True``.
 """
 if pos is None:
 pos = [0, 0]

 # xp1,yp1,xp2,yp2 = blit area on im2
 # x1,y1,x2,y2 = area of im1 to blit on im2
 xp, yp = pos
 x1 = max(0, -xp)
 y1 = max(0, -yp)
 h1, w1 = im1.shape[:2]
 h2, w2 = im2.shape[:2]
 xp2 = min(w2, xp + w1)
 yp2 = min(h2, yp + h1)
 x2 = min(w1, w2 - xp)
 y2 = min(h1, h2 - yp)
 xp1 = max(0, xp)
 yp1 = max(0, yp)

 if (xp1 >= xp2) or (yp1 >= yp2):
 return im2

 blitted = im1[y1:y2, x1:x2]

 new_im2 = +im2

 if mask is None:
 new_im2[yp1:yp2, xp1:xp2] = blitted
 else:
 mask = mask[y1:y2, x1:x2]
 if len(im1.shape) == 3:
 mask = np.dstack(3 * [mask])
 blit_region = new_im2[yp1:yp2, xp1:xp2]
 new_im2[yp1:yp2, xp1:xp2] = (1.0 * mask * blitted + (1.0 - mask) * blit_region)
 
 return new_im2.astype('uint8') if (not ismask) else new_im2



and so, Rotem is right.


new_im2[yp1:yp2, xp1:xp2] = (1.0 * mask * blitted + (1.0 - mask) * blit_region)



is


(alpha * img_rgb + (1.0 - alpha) * bg)



and this is how moviepy composites. And this is why we see black at the edges.


-
FFmpeg / Avconv video playback problems - black or green tint
21 octobre 2014, par scottpatersonI am using FFmpeg / Avconv to convert a raw video file to a MP4 or AVI. Both FFmpeg and Avconv have the same problem.
-
The output video, both MP4 or AVI, play 100% percent perfect on Linux Mint in the default video player.
-
On Windows in WMP the MP4 plays, but the video is black, and the AVI plays and shows video but it has a green tint. On Windows in Quicktime both formats video is black.
Here is the command I am using :
avconv -i /home/scott/Desktop/out.wav -f rawvideo -pix_fmt rgb32 -s:v 540x240 -i
/home/scott/Desktop/out.raw -c:v libx264 -strict -2 -preset ultrafast -b:v 160k
/home/scott/Dropbox/code/out.avi-
I have spent a lot of time messing with the -pix_fmt and trying different pixel format, so far rgb32 returns the best results.
-
I have also tried -sws_flags options such as lanczos+accurate_rnd - but this did not help.
How can I get this to play the same in all video players ?
Thanks !
-
-
I get black screen when i record the headless selenium driver with xvfb and ffmpeg [closed]
28 juillet 2022, par Saran Rajxvfb-run —listen-tcp —server-num 44 -s "-ac -screen 0 1920x1080x24" mvn clean test &

export DISPLAY=:44

ffmpeg -f x11grab -video_size 1920x1080 -i :44 -codec:v libx264 -r 12 video.mp4

This is the bash script i am using to run the selenium test cases(in headless mode) with maven as the build tool in port 44 and capture it.
But when i execute it i only get a black screen. What to do ?