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The pirate bay depuis la Belgique
1er avril 2013, par
Mis à jour : Avril 2013
Langue : français
Type : Image
Autres articles (33)
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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 -
Les formats acceptés
28 janvier 2010, parLes commandes suivantes permettent d’avoir des informations sur les formats et codecs gérés par l’installation local de ffmpeg :
ffmpeg -codecs ffmpeg -formats
Les format videos acceptés en entrée
Cette liste est non exhaustive, elle met en exergue les principaux formats utilisés : h264 : H.264 / AVC / MPEG-4 AVC / MPEG-4 part 10 m4v : raw MPEG-4 video format flv : Flash Video (FLV) / Sorenson Spark / Sorenson H.263 Theora wmv :
Les formats vidéos de sortie possibles
Dans un premier temps on (...) -
List of compatible distributions
26 avril 2011, parThe table below is the list of Linux distributions compatible with the automated installation script of MediaSPIP. Distribution nameVersion nameVersion number Debian Squeeze 6.x.x Debian Weezy 7.x.x Debian Jessie 8.x.x Ubuntu The Precise Pangolin 12.04 LTS Ubuntu The Trusty Tahr 14.04
If you want to help us improve this list, you can provide us access to a machine whose distribution is not mentioned above or send the necessary fixes to add (...)
Sur d’autres sites (3800)
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Downloading Youtube videos frames with FFMPEG without downloading the entire videos [closed]
11 mars 2023, par zulle99I'm wondering if it is possible to download youtube videos frames using FFMPEG and not opencv without downloading the entire videos first. I'm asking this since it is known that opencv is very slow doing this and takes a huge amount of time if the sequence of videos is big like in my use case.


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Parallelize Youtube video frame download using yt-dlp and cv2
4 mars 2023, par zulle99My task is to download multiple sequences of successive low resolution frames of Youtube videos.


I summarize the main parts of the process :


- 

- Each bag of shots have a dimension of half a second (depending on the current fps)
- In order to grab useful frames I've decided to remove the initial and final 10% of each video since it is common to have an intro and outro. Moreover
- I've made an array of pair of initial and final frame to distribute the load on multiple processes using
ProcessPoolExecutor(max_workers=multiprocessing.cpu_count())
- In case of failure/exception I completly remove the relative directory










The point is that it do not scale up, since while running I noticesd that all CPUs had always a load lower that the 20% more or less. In addition since with these shots I have to run multiple CNNs, to prevent overfitting it is suggested to have a big dataset and not a bounch of shots.


Here it is the code :


import yt_dlp
import os
from tqdm import tqdm
import cv2
import shutil
import time
import random
from concurrent.futures import ProcessPoolExecutor
import multiprocessing
import pandas as pd
import numpy as np
from pathlib import Path
import zipfile


# PARAMETERS
percentage_train_test = 50
percentage_bag_shots = 20
percentage_to_ignore = 10

zip_f_name = f'VideoClassificationDataset_{percentage_train_test}_{percentage_bag_shots}_{percentage_to_ignore}'
dataset_path = Path('/content/VideoClassificationDataset')

# DOWNOAD ZIP FILES
!wget --no-verbose https://github.com/gtoderici/sports-1m-dataset/archive/refs/heads/master.zip

# EXTRACT AND DELETE THEM
!unzip -qq -o '/content/master.zip' 
!rm '/content/master.zip'

DATA = {'train_partition.txt': {},
 'test_partition.txt': {}}

LABELS = []

train_dict = {}
test_dict = {}

path = '/content/sports-1m-dataset-master/original'

for f in os.listdir(path):
 with open(path + '/' + f) as f_txt:
 lines = f_txt.readlines()
 for line in lines:
 splitted_line = line.split(' ')
 label_indices = splitted_line[1].rstrip('\n').split(',') 
 DATA[f][splitted_line[0]] = list(map(int, label_indices))

with open('/content/sports-1m-dataset-master/labels.txt') as f_labels:
 LABELS = f_labels.read().splitlines()


TRAIN = DATA['train_partition.txt']
TEST = DATA['test_partition.txt']
print('Original Train Test length: ', len(TRAIN), len(TEST))

# sample a subset percentage_train_test
TRAIN = dict(random.sample(TRAIN.items(), (len(TRAIN)*percentage_train_test)//100))
TEST = dict(random.sample(TEST.items(), (len(TEST)*percentage_train_test)//100))

print(f'Sampled {percentage_train_test} Percentage Train Test length: ', len(TRAIN), len(TEST))


if not os.path.exists(dataset_path): os.makedirs(dataset_path)
if not os.path.exists(f'{dataset_path}/train'): os.makedirs(f'{dataset_path}/train')
if not os.path.exists(f'{dataset_path}/test'): os.makedirs(f'{dataset_path}/test')



Function to extract a sequence of continuous frames :


def extract_frames(directory, url, idx_bag, start_frame, end_frame):
 capture = cv2.VideoCapture(url)
 count = start_frame

 capture.set(cv2.CAP_PROP_POS_FRAMES, count)
 os.makedirs(f'{directory}/bag_of_shots{str(idx_bag)}')

 while count < end_frame:

 ret, frame = capture.read()

 if not ret: 
 shutil.rmtree(f'{directory}/bag_of_shots{str(idx_bag)}')
 return False

 filename = f'{directory}/bag_of_shots{str(idx_bag)}/shot{str(count - start_frame)}.png'

 cv2.imwrite(filename, frame)
 count += 1

 capture.release()
 return True



Function to spread the load along multiple processors :


def video_to_frames(video_url, labels_list, directory, dic, percentage_of_bags):
 url_id = video_url.split('=')[1]
 path_until_url_id = f'{dataset_path}/{directory}/{url_id}'
 try: 

 ydl_opts = {
 'ignoreerrors': True,
 'quiet': True,
 'nowarnings': True,
 'simulate': True,
 'ignorenoformatserror': True,
 'verbose':False,
 'cookies': '/content/all_cookies.txt',
 #https://stackoverflow.com/questions/63329412/how-can-i-solve-this-youtube-dl-429
 }
 ydl = yt_dlp.YoutubeDL(ydl_opts)
 info_dict = ydl.extract_info(video_url, download=False)

 if(info_dict is not None and info_dict['fps'] >= 20):
 # I must have a least 20 frames per seconds since I take half of second bag of shots for every video

 formats = info_dict.get('formats', None)

 # excluding the initial and final 10% of each video to avoid noise
 video_length = info_dict['duration'] * info_dict['fps']

 shots = info_dict['fps'] // 2

 to_ignore = (video_length * percentage_to_ignore) // 100
 new_len = video_length - (to_ignore * 2)
 tot_stored_bags = ((new_len // shots) * percentage_of_bags) // 100 # ((total_possbile_bags // shots) * percentage_of_bags) // 100
 if tot_stored_bags == 0: tot_stored_bags = 1 # minimum 1 bag of shots

 skip_rate_between_bags = (new_len - (tot_stored_bags * shots)) // (tot_stored_bags-1) if tot_stored_bags > 1 else 0

 chunks = [[to_ignore+(bag*(skip_rate_between_bags+shots)), to_ignore+(bag*(skip_rate_between_bags+shots))+shots] for bag in range(tot_stored_bags)]
 # sequence of [[start_frame, end_frame], [start_frame, end_frame], [start_frame, end_frame], ...]


 # ----------- For the moment I download only shots form video that has 144p resolution -----------

 res = {
 '160': '144p',
 '133': '240p',
 '134': '360p',
 '135': '360p',
 '136': '720p'
 }

 format_id = {}
 for f in formats: format_id[f['format_id']] = f
 #for res in resolution_id:
 if list(res.keys())[0] in list(format_id.keys()):
 video = format_id[list(res.keys())[0]]
 url = video.get('url', None)
 if(video.get('url', None) != video.get('manifest_url', None)):

 if not os.path.exists(path_until_url_id): os.makedirs(path_until_url_id)

 with ProcessPoolExecutor(max_workers=multiprocessing.cpu_count()) as executor:
 for idx_bag, f in enumerate(chunks): 
 res = executor.submit(
 extract_frames, directory = path_until_url_id, url = url, idx_bag = idx_bag, start_frame = f[0], end_frame = f[1])
 
 if res.result() is True: 
 l = np.zeros(len(LABELS), dtype=int) 
 for label in labels_list: l[label] = 1
 l = np.append(l, [shots]) # appending the number of shots taken in the list before adding it on the dictionary

 dic[f'{directory}/{url_id}/bag_of_shots{str(idx_bag)}'] = l.tolist()


 except Exception as e:
 shutil.rmtree(path_until_url_id)
 pass



Download of TRAIN bag of shots :


start_time = time.time()
pbar = tqdm(enumerate(TRAIN.items()), total = len(TRAIN.items()), leave=False)

for _, (url, labels_list) in pbar: video_to_frames(
 video_url = url, labels_list = labels_list, directory = 'train', dic = train_dict, percentage_of_bags = percentage_bag_shots)

print("--- %s seconds ---" % (time.time() - start_time))



Download of TEST bag of shots :


start_time = time.time()
pbar = tqdm(enumerate(TEST.items()), total = len(TEST.items()), leave=False)

for _, (url, labels_list) in pbar: video_to_frames(
 video_url = url, labels_list = labels_list, directory = 'test', dic = test_dict, percentage_of_bags = percentage_bag_shots)

print("--- %s seconds ---" % (time.time() - start_time))



Save the .csv files


train_df = pd.DataFrame.from_dict(train_dict, orient='index', dtype=int).reset_index(level=0)
train_df = train_df.rename(columns={train_df.columns[-1]: 'shots'})
train_df.to_csv('/content/VideoClassificationDataset/train.csv', index=True)

test_df = pd.DataFrame.from_dict(test_dict, orient='index', dtype=int).reset_index(level=0)
test_df = test_df.rename(columns={test_df.columns[-1]: 'shots'})
test_df.to_csv('/content/VideoClassificationDataset/test.csv', index=True)



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ffmpeg youtube livestream not working
21 avril 2017, par SelectToday i tried using ffmpeg on my debian 8.3 server to livestream 24/7 hours. However it doesnt work.
#! /bin/bash
INRES="1280x1024" # input resolution (The resolution of the program you want to stream!)
OUTRES="1024x790" # Output resolution (The resolution you want your stream to be at)
FPS="60" # target FPS
QUAL="ultrafast"
# one of the many FFMPEG presets that can be used
# If you have low bandwidth, put the qual preset on 'ultrafast' (upload bandwidth)
# If you have medium bandwitch put it on normal to medium or fast
STREAM_KEY="hidden" # this is your streamkey
ffmpeg -f "file.avi" -s "$INRES" -r "$FPS" -i :0.0 \
-f alsa -ac 2 -i pulse -vcodec libx264 -s "$OUTRES" \
-acodec libmp3lame -ab 128k -ar 44100 -threads 0 \
-f flv "rtmp://a.rtmp.youtube.com/live2"it gives me the output
Unknown input format : ’file.avi’