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Médias (2)
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Granite de l’Aber Ildut
9 septembre 2011, par
Mis à jour : Septembre 2011
Langue : français
Type : Texte
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Géodiversité
9 septembre 2011, par ,
Mis à jour : Août 2018
Langue : français
Type : Texte
Autres articles (77)
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Personnaliser en ajoutant son logo, sa bannière ou son image de fond
5 septembre 2013, parCertains thèmes prennent en compte trois éléments de personnalisation : l’ajout d’un logo ; l’ajout d’une bannière l’ajout d’une image de fond ;
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Ecrire une actualité
21 juin 2013, parPrésentez les changements dans votre MédiaSPIP ou les actualités de vos projets sur votre MédiaSPIP grâce à la rubrique actualités.
Dans le thème par défaut spipeo de MédiaSPIP, les actualités sont affichées en bas de la page principale sous les éditoriaux.
Vous pouvez personnaliser le formulaire de création d’une actualité.
Formulaire de création d’une actualité Dans le cas d’un document de type actualité, les champs proposés par défaut sont : Date de publication ( personnaliser la date de publication ) (...) -
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
Sur d’autres sites (5849)
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Availability of WebM (VP8) Video Hardware IP Designs
10 janvier 2011, par noreply@blogger.com (John Luther)Hello from the frigid city of Oulu, in the far north of Finland. Our WebM hardware development team, formerly part of On2 Technologies, is now up-to-speed and working hard on a number of video efforts for WebM.
- VP8 (the video codec used in WebM) hardware decoder IP is available from Google for semiconductor companies who want to support high-quality WebM playback in their chipsets.
- The Oulu team will release the first VP8 video hardware encoder IP in the first quarter of 2011. We have the IP running in an FPGA environment, and rigorous testing is underway. Once all features have been tested and implemented, the encoder will be launched as well.
WebM video hardware IPs are implemented and delivered as RTL (VHDL/Verilog) source code, which is a register-level hardware description language for creating digital circuit designs. The code is based on the Hantro brand video IP from On2, which has been successfully deployed by numerous chipset companies around the world. Our designs support VP8 up to 1080p resolution and can run 30 or 60fps, depending on the foundry process and hardware clock frequency.
The WebM/VP8 hardware decoder implementation has already been licensed to over twenty partners and is proven in silicon. We expect the first commercial chips to integrate our VP8 decoder IP to be available in the first quarter of 2011. For example, Chinese semiconductor maker Rockchip last week demonstrated full WebM hardware playback on their new RK29xx series processor at CES in Las Vegas (video below).
Note : To view the video in WebM format, ensure that you’ve enrolled in the YouTube HTML5 trial and are using a WebM-compatible browser. You can also view the video on YouTube.Hardware implementations of the VP8 encoder also bring exciting possibilities for WebM in portable devices. Not only can hardware-accelerated devices play high-quality WebM content, but hardware encoding also enables high-resolution, real-time video communications apps on the same devices. For example, when VP8 video encoding is fully off-loaded to a hardware accelerator, you can run 720p or even 1080p video conferencing at full framerate on a portable device with minimal battery use.
The WebM hardware video IP team will be focusing on further developing the VP8 hardware designs while also helping our semiconductor partners to implement WebM video compression in their chipsets. If you have any questions, please visit our Hardware page.
Happy New Year to the WebM community !
Jani Huoponen, Product Manager
Aki Kuusela, Engineering Manager -
Change AVI creation date with ffmpeg ?
1er novembre 2016, par brockAs far as I can tell the following ffmpeg command should copy all existing metadata in the input file to the output file and modify the specified field in the output file :
ffmpeg -i VID_20130502_220104.avi -metadata creation_time="2013-05-02 22:01:04" -codec copy VID_20130502_220104-2.avi
Instead, it seems to strip all metadata from the output file. Here is the output of a few commands. I am going nuts. I think this should work, but why is it not ?
Command to edit the creation time :
ffmpeg -i VID_20130502_220104.avi -metadata creation_time="2013-05-02 22:01:04" -codec copy VID_20130502_220104-2.avi
ffmpeg version 3.1.5 Copyright (c) 2000-2016 the FFmpeg developers
built with gcc 5.4.0 (GCC)
configuration: --enable-gpl --enable-version3 --disable-w32threads --enable-dxva2 --enable-libmfx --enable-nvenc --enable-avisynth --enable-bzlib --enable-libebur128 --enable-fontconfig --enable-frei0r --enable-gnutls --enable-iconv --enable-libass --enable-libbluray --enable-libbs2b --enable-libcaca --enable-libfreetype --enable-libgme --enable-libgsm --enable-libilbc --enable-libmodplug --enable-libmp3lame --enable-libopencore-amrnb --enable-libopencore-amrwb --enable-libopenh264 --enable-libopenjpeg --enable-libopus --enable-librtmp --enable-libschroedinger --enable-libsnappy --enable-libsoxr --enable-libspeex --enable-libtheora --enable-libtwolame --enable-libvidstab --enable-libvo-amrwbenc --enable-libvorbis --enable-libvpx --enable-libwavpack --enable-libwebp --enable-libx264 --enable-libx265 --enable-libxavs --enable-libxvid --enable-libzimg --enable-lzma --enable-decklink --enable-zlib
libavutil 55. 28.100 / 55. 28.100
libavcodec 57. 48.101 / 57. 48.101
libavformat 57. 41.100 / 57. 41.100
libavdevice 57. 0.101 / 57. 0.101
libavfilter 6. 47.100 / 6. 47.100
libswscale 4. 1.100 / 4. 1.100
libswresample 2. 1.100 / 2. 1.100
libpostproc 54. 0.100 / 54. 0.100
Guessed Channel Layout for Input Stream #0.1 : mono
Input #0, avi, from 'VID_20130502_220104.avi':
Metadata:
encoder :
maker : NIKON
model : COOLPIX S4300
creation_time : 2011-01-01 00:00:00
Duration: 00:01:30.50, start: 0.000000, bitrate: 32135 kb/s
Stream #0:0: Video: mjpeg (MJPG / 0x47504A4D), yuvj422p(pc, bt470bg/unknown/unknown), 1280x720, 31782 kb/s, 30 fps, 30 tbr, 30 tbn, 30 tbc
Stream #0:1: Audio: pcm_s16le ([1][0][0][0] / 0x0001), 22050 Hz, 1 channels, s16, 352 kb/s
[avi @ 000000000032ad40] Using AVStream.codec to pass codec parameters to muxers is deprecated, use AVStream.codecpar instead.
Last message repeated 1 times
Output #0, avi, to 'VID_20130502_220104-2.avi':
Metadata:
creation_time : 2013-05-02 22:01:04
maker : NIKON
model : COOLPIX S4300
ISFT : Lavf57.41.100
Stream #0:0: Video: mjpeg (MJPG / 0x47504A4D), yuvj422p(pc, bt470bg/unknown/unknown), 1280x720, q=2-31, 31782 kb/s, 30 fps, 30 tbr, 30 tbn, 30 tbc
Stream #0:1: Audio: pcm_s16le ([1][0][0][0] / 0x0001), 22050 Hz, mono, 352 kb/s
Stream mapping:
Stream #0:0 -> #0:0 (copy)
Stream #0:1 -> #0:1 (copy)
Press [q] to stop, [?] for help
frame= 891 fps=0.0 q=-1.0 size= 116171kB time=00:00:29.69 bitrate=32043.1kbits/s speed=59.4x
frame= 1739 fps=1739 q=-1.0 size= 227191kB time=00:00:57.96 bitrate=32107.5kbits/s speed= 58x
frame= 2609 fps=1739 q=-1.0 size= 340940kB time=00:01:26.96 bitrate=32115.9kbits/s speed= 58x
frame= 2715 fps=1734 q=-1.0 Lsize= 355018kB time=00:01:30.49 bitrate=32136.3kbits/s speed=57.8x
video:350984kB audio:3897kB subtitle:0kB other streams:0kB global headers:0kB muxing overhead: 0.038597%Command to inspect the output file metadata with ffmpeg :
ffmpeg -i VID_20130502_220104-2.avi
ffmpeg version 3.1.5 Copyright (c) 2000-2016 the FFmpeg developers
built with gcc 5.4.0 (GCC)
configuration: --enable-gpl --enable-version3 --disable-w32threads --enable-dxva2 --enable-libmfx --enable-nvenc --enable-avisynth --enable-bzlib --enable-libebur128 --enable-fontconfig --enable-frei0r --enable-gnutls --enable-iconv --enable-libass --enable-libbluray --enable-libbs2b --enable-libcaca --enable-libfreetype --enable-libgme --enable-libgsm --enable-libilbc --enable-libmodplug --enable-libmp3lame --enable-libopencore-amrnb --enable-libopencore-amrwb --enable-libopenh264 --enable-libopenjpeg --enable-libopus --enable-librtmp --enable-libschroedinger --enable-libsnappy --enable-libsoxr --enable-libspeex --enable-libtheora --enable-libtwolame --enable-libvidstab --enable-libvo-amrwbenc --enable-libvorbis --enable-libvpx --enable-libwavpack --enable-libwebp --enable-libx264 --enable-libx265 --enable-libxavs --enable-libxvid --enable-libzimg --enable-lzma --enable-decklink --enable-zlib
libavutil 55. 28.100 / 55. 28.100
libavcodec 57. 48.101 / 57. 48.101
libavformat 57. 41.100 / 57. 41.100
libavdevice 57. 0.101 / 57. 0.101
libavfilter 6. 47.100 / 6. 47.100
libswscale 4. 1.100 / 4. 1.100
libswresample 2. 1.100 / 2. 1.100
libpostproc 54. 0.100 / 54. 0.100
Guessed Channel Layout for Input Stream #0.1 : mono
Input #0, avi, from 'VID_20130502_220104-2.avi':
Metadata:
encoder : Lavf57.41.100
Duration: 00:01:30.50, start: 0.000000, bitrate: 32136 kb/s
Stream #0:0: Video: mjpeg (MJPG / 0x47504A4D), yuvj422p(pc, bt470bg/unknown/unknown), 1280x720, 31782 kb/s, 30 fps, 30 tbr, 30 tbn, 30 tbc
Stream #0:1: Audio: pcm_s16le ([1][0][0][0] / 0x0001), 22050 Hz, 1 channels, s16, 352 kb/s
At least one output file must be specifiedCommand to inspect the input file metadata with exiftool :
exiftool.exe VID_20130502_220104.avi
ExifTool Version Number : 10.30
File Name : VID_20130502_220104.avi
Directory : .
File Size : 347 MB
File Modification Date/Time : 2013:05:13 16:33:52-04:00
File Access Date/Time : 2015:11:10 23:08:25-05:00
File Creation Date/Time : 2015:11:10 23:08:25-05:00
File Permissions : rw-rw-rw-
File Type : AVI
File Type Extension : avi
MIME Type : video/x-msvideo
Frame Rate : 30
Max Data Rate : 488.3 kB/s
Frame Count : 2715
Stream Count : 2
Stream Type : Video
Video Codec : mjpg
Video Frame Rate : 30
Video Frame Count : 2715
Quality : 10000
Sample Size : Variable
Image Width : 1280
Image Height : 720
Planes : 1
Bit Depth : 24
Compression : MJPG
Image Length : 2764800
Pixels Per Meter X : 0
Pixels Per Meter Y : 0
Num Colors : Use BitDepth
Num Important Colors : All
Audio Codec :
Audio Sample Rate : 22050
Audio Sample Count : 1995256
Encoding : Microsoft PCM
Num Channels : 1
Sample Rate : 22050
Avg Bytes Per Sec : 44100
Bits Per Sample : 16
Maker Note Type : NIKON
Maker Note Version : 0.1.0.0
Make : NIKON
Model : COOLPIX S4300
Software : V1.0
Equipment : NIKON DIGITAL CAMERA
Orientation : Horizontal (normal)
Exposure Time : 1/15
F Number : 3.5
Exposure Compensation : 0
Max Aperture Value : 3.2
Metering Mode : Multi-segment
Focal Length : 4.6 mm
X Resolution : 72
Y Resolution : 72
Resolution Unit : inches
Date/Time Original : 2011:01:01 00:00:00
Create Date : 2011:01:01 00:00:00
Focus Mode : AF-S
Digital Zoom : 1
Color Mode : COLOR
Sharpness : AUTO
White Balance : NORMAL
Noise Reduction : OFF
Thumbnail Image : (Binary data 3082 bytes, use -b option to extract)
Aperture : 3.5
Duration : 0:01:30
Image Size : 1280x720
Megapixels : 0.922
Shutter Speed : 1/15
Focal Length : 4.6 mmCommand to inspect the output file metadata with exiftool :
exiftool.exe VID_20130502_220104-2.avi
ExifTool Version Number : 10.30
File Name : VID_20130502_220104-2.avi
Directory : .
File Size : 347 MB
File Modification Date/Time : 2016:11:01 00:17:38-04:00
File Access Date/Time : 2016:11:01 00:17:36-04:00
File Creation Date/Time : 2016:11:01 00:15:18-04:00
File Permissions : rw-rw-rw-
File Type : AVI
File Type Extension : avi
MIME Type : video/x-msvideo
Frame Rate : 30
Max Data Rate : 3923 kB/s
Frame Count : 2715
Stream Count : 2
Stream Type : Video
Video Codec : MJPG
Video Frame Rate : 30
Video Frame Count : 2715
Quality : Default
Sample Size : Variable
Image Width : 1280
Image Height : 720
Planes : 1
Bit Depth : 24
Compression : MJPG
Image Length : 2764800
Pixels Per Meter X : 0
Pixels Per Meter Y : 0
Num Colors : Use BitDepth
Num Important Colors : All
Audio Codec : .
Audio Sample Rate : 22050
Audio Sample Count : 1995256
Encoding : Microsoft PCM
Num Channels : 1
Sample Rate : 22050
Avg Bytes Per Sec : 44100
Bits Per Sample : 16
Software : Lavf57.41.100
Duration : 0:01:30
Image Size : 1280x720
Megapixels : 0.922 -
How to obtain time markers for video splitting using python/OpenCV
30 mars 2016, par Bleddyn Raw-ReesHi I’m new to the world of programming and computer vision so please bare with me.
I’m working on my MSc project which is researching automated deletion of low value content in digital file stores. I’m specifically looking at the sort of long shots that often occur in natural history filming whereby a static camera is left rolling in order to capture the rare snow leopard or whatever. These shots may only have some 60s of useful content with perhaps several hours of worthless content either side.
As a first step I have a simple motion detection program from Adrian Rosebrock’s tutorial [http://www.pyimagesearch.com/2015/05/25/basic-motion-detection-and-tracking-with-python-and-opencv/#comment-393376]. Next I intend to use FFMPEG to split the video.
What I would like help with is how to get in and out points based on the first and last points that motion is detected in the video.
Here is the code should you wish to see it...
# import the necessary packages
import argparse
import datetime
import imutils
import time
import cv2
# construct the argument parser and parse the arguments
ap = argparse.ArgumentParser()
ap.add_argument("-v", "--video", help="path to the video file")
ap.add_argument("-a", "--min-area", type=int, default=500, help="minimum area size")
args = vars(ap.parse_args())
# if the video argument is None, then we are reading from webcam
if args.get("video", None) is None:
camera = cv2.VideoCapture(0)
time.sleep(0.25)
# otherwise, we are reading from a video file
else:
camera = cv2.VideoCapture(args["video"])
# initialize the first frame in the video stream
firstFrame = None
# loop over the frames of the video
while True:
# grab the current frame and initialize the occupied/unoccupied
# text
(grabbed, frame) = camera.read()
text = "Unoccupied"
# if the frame could not be grabbed, then we have reached the end
# of the video
if not grabbed:
break
# resize the frame, convert it to grayscale, and blur it
frame = imutils.resize(frame, width=500)
gray = cv2.cvtColor(frame, cv2.COLOR_BGR2GRAY)
gray = cv2.GaussianBlur(gray, (21, 21), 0)
# if the first frame is None, initialize it
if firstFrame is None:
firstFrame = gray
continue
# compute the absolute difference between the current frame and
# first frame
frameDelta = cv2.absdiff(firstFrame, gray)
thresh = cv2.threshold(frameDelta, 25, 255, cv2.THRESH_BINARY)[1]
# dilate the thresholded image to fill in holes, then find contours
# on thresholded image
thresh = cv2.dilate(thresh, None, iterations=2)
(_, cnts, _) = cv2.findContours(thresh.copy(), cv2.RETR_EXTERNAL, cv2.CHAIN_APPROX_SIMPLE)
# loop over the contours
for c in cnts:
# if the contour is too small, ignore it
if cv2.contourArea(c) < args["min_area"]:
continue
# compute the bounding box for the contour, draw it on the frame,
# and update the text
(x, y, w, h) = cv2.boundingRect(c)
cv2.rectangle(frame, (x, y), (x + w, y + h), (0, 255, 0), 2)
text = "Occupied"
# draw the text and timestamp on the frame
cv2.putText(frame, "Room Status: {}".format(text), (10, 20),
cv2.FONT_HERSHEY_SIMPLEX, 0.5, (0, 0, 255), 2)
cv2.putText(frame, datetime.datetime.now().strftime("%A %d %B %Y %I:%M:%S%p"),
(10, frame.shape[0] - 10), cv2.FONT_HERSHEY_SIMPLEX, 0.35, (0, 0, 255), 1)
# show the frame and record if the user presses a key
cv2.imshow("Security Feed", frame)
cv2.imshow("Thresh", thresh)
cv2.imshow("Frame Delta", frameDelta)
key = cv2.waitKey(1) & 0xFF
# if the `q` key is pressed, break from the lop
if key == ord("q"):
break
# cleanup the camera and close any open windows
camera.release()
cv2.destroyAllWindows()Thanks !