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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 -
Encoding and processing into web-friendly formats
13 avril 2011, parMediaSPIP automatically converts uploaded files to internet-compatible formats.
Video files are encoded in MP4, Ogv and WebM (supported by HTML5) and MP4 (supported by Flash).
Audio files are encoded in MP3 and Ogg (supported by HTML5) and MP3 (supported by Flash).
Where possible, text is analyzed in order to retrieve the data needed for search engine detection, and then exported as a series of image files.
All uploaded files are stored online in their original format, so you can (...) -
Keeping control of your media in your hands
13 avril 2011, parThe vocabulary used on this site and around MediaSPIP in general, aims to avoid reference to Web 2.0 and the companies that profit from media-sharing.
While using MediaSPIP, you are invited to avoid using words like "Brand", "Cloud" and "Market".
MediaSPIP is designed to facilitate the sharing of creative media online, while allowing authors to retain complete control of their work.
MediaSPIP aims to be accessible to as many people as possible and development is based on expanding the (...)
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ffmpeg takes too long to start
17 octobre 2020, par SuspendedI have this command in python script, in a loop :


ffmpeg -i somefile.mp4 -ss 00:03:12 -t 00:00:35 piece.mp4 -loglevel error -stats


It cuts out pieces of input file (-i). Input filename, as well as start time (-ss) and length of the piece I cut out (-t) varies, so it reads number of mp4 files and cuts out number of pieces from each one. During execution of the script it might be called around 100 times. My problem is that each time before it starts, there is a delay of 6-15 seconds and it adds up to significant time. How can I get it to start immediately ?


Initially I thought it was process priority problem, but I noticed that even during the "pause", all processors work at 100%, so apparently some work is being done.


The script (process_videos.py) :


import subprocess
import sys
import math
import time

class TF:
 """TimeFormatter class (TF).
This class' reason for being is to convert time in short
form, e.g. 1:33, 0:32, or 23 into long form accepted by
mp4cut function in bash, e.g. 00:01:22, 00:00:32, etc"""

def toLong(self, shrt):
 """Converts time to its long form"""
 sx = '00:00:00'
 ladd = 8 - len(shrt)
 n = sx[:ladd] + shrt
 return n

def toShort(self, lng):
 """Converts time to short form"""
 if lng[0] == '0' or lng[0] == ':':
 return self.toShort(lng[1:])
 else:
 return lng

def toSeconds(self, any_time):
 """Converts time to seconds"""
 if len(any_time) < 3:
 return int(any_time)
 tt = any_time.split(':')
 if len(any_time) < 6: 
 return int(tt[0])*60 + int(tt[1])
 return int(tt[0])*3600 + int(tt[1])*60 + int(tt[2])

def toTime(self, secsInt):
 """"""
 tStr = ''
 hrs, mins, secs = 0, 0, 0
 if secsInt >= 3600:
 hrs = math.floor(secsInt / 3600)
 secsInt = secsInt % 3600
 if secsInt >= 60:
 mins = math.floor(secsInt / 60)
 secsInt = secsInt % 60
 secs = secsInt
 return str(hrs).zfill(2) + ':' + str(mins).zfill(2) + ':' + str(secs).zfill(2)

def minus(self, t_start, t_end):
 """"""
 t_e = self.toSeconds(t_end)
 t_s = self.toSeconds(t_start)
 t_r = t_e - t_s
 hrs, mins, secs = 0, 0, 0
 if t_r >= 3600:
 hrs = math.floor(t_r / 3600)
 t_r = t_r - (hrs * 3600)
 if t_r >= 60:
 mins = math.floor(t_r / 60)
 t_r = t_r - (mins * 60)
 secs = t_r
 hrsf = str(hrs).zfill(2)
 minsf = str(mins).zfill(2)
 secsf = str(secs).zfill(2)
 t_fnl = hrsf + ':' + minsf + ':' + secsf
 return t_fnl

def go_main():
 tf = TF()
 vid_n = 0
 arglen = len(sys.argv)
 if arglen == 2:
 with open(sys.argv[1], 'r') as f_in:
 lines = f_in.readlines()
 start = None
 end = None
 cnt = 0
 for line in lines:
 if line[:5] == 'BEGIN':
 start = cnt
 if line[:3] == 'END':
 end = cnt
 cnt += 1
 if start == None or end == None:
 print('Invalid file format. start = {}, end = {}'.format(start,end))
 return
 else:
 lines_r = lines[start+1:end]
 del lines
 print('videos to process: {}'.format(len(lines_r)))
 f_out_prefix = ""
 for vid in lines_r:
 vid_n += 1
 print('\nProcessing video {}/{}'.format(vid_n, len(lines_r)))
 f_out_prefix = 'v' + str(vid_n) + '-'
 dat = vid.split('!')[1:3]
 title = dat[0]
 dat_t = dat[1].split(',')
 v_pieces = len(dat_t)
 piece_n = 0
 video_pieces = []
 cmd1 = "echo -n \"\" > tmpfile"
 subprocess.run(cmd1, shell=True) 
 print(' new tmpfile created')
 for v_times in dat_t:
 piece_n += 1
 f_out = f_out_prefix + str(piece_n) + '.mp4'
 video_pieces.append(f_out)
 print(' piece filename {} added to video_pieces list'.format(f_out))
 v_times_spl = v_times.split('-')
 v_times_start = v_times_spl[0]
 v_times_end = v_times_spl[1]
 t_st = tf.toLong(v_times_start)
 t_dur = tf.toTime(tf.toSeconds(v_times_end) - tf.toSeconds(v_times_start))
 cmd3 = ["ffmpeg", "-i", title, "-ss", t_st, "-t", t_dur, f_out, "-loglevel", "error", "-stats"]
 print(' cutting out piece {}/{} - {}'.format(piece_n, len(dat_t), t_dur))
 subprocess.run(cmd3)
 for video_piece_name in video_pieces:
 cmd4 = "echo \"file " + video_piece_name + "\" >> tmpfile"
 subprocess.run(cmd4, shell=True)
 print(' filename {} added to tmpfile'.format(video_piece_name))
 vname = f_out_prefix[:-1] + ".mp4"
 print(' name of joined file: {}'.format(vname))
 cmd5 = "ffmpeg -f concat -safe 0 -i tmpfile -c copy joined.mp4 -loglevel error -stats"
 to_be_joined = " ".join(video_pieces)
 print(' joining...')
 join_cmd = subprocess.Popen(cmd5, shell=True)
 join_cmd.wait()
 print(' joined!')
 cmd6 = "mv joined.mp4 " + vname
 rename_cmd = subprocess.Popen(cmd6, shell=True)
 rename_cmd.wait()
 print(' File joined.mp4 renamed to {}'.format(vname))
 cmd7 = "rm " + to_be_joined
 rm_cmd = subprocess.Popen(cmd7, shell=True)
 rm_cmd.wait()
 print('rm command completed - pieces removed')
 cmd8 = "rm tmpfile"
 subprocess.run(cmd8, shell=True)
 print('tmpfile removed')
 print('All done')
 else:
 print('Incorrect number of arguments')

############################
if __name__ == '__main__':
 go_main()


process_videos.py is called from bash terminal like this :


$ python process_videos.py video_data 


video_data file has the following format :


BEGIN
!first_video.mp4!3-23,55-1:34,2:01-3:15,3:34-3:44!
!second_video.mp4!2-7,12-44,1:03-1:33!
END


My system details :


System: Host: snowflake Kernel: 5.4.0-52-generic x86_64 bits: 64 Desktop: Gnome 3.28.4
 Distro: Ubuntu 18.04.5 LTS
Machine: Device: desktop System: Gigabyte product: N/A serial: N/A
Mobo: Gigabyte model: Z77-D3H v: x.x serial: N/A BIOS: American Megatrends v: F14 date: 05/31/2012
CPU: Quad core Intel Core i5-3570 (-MCP-) cache: 6144 KB 
 clock speeds: max: 3800 MHz 1: 1601 MHz 2: 1601 MHz 3: 1601 MHz 4: 1602 MHz
Drives: HDD Total Size: 1060.2GB (55.2% used)
 ID-1: /dev/sda model: ST31000524AS size: 1000.2GB
 ID-2: /dev/sdb model: Corsair_Force_GT size: 60.0GB
Partition: ID-1: / size: 366G used: 282G (82%) fs: ext4 dev: /dev/sda1
 ID-2: swap-1 size: 0.70GB used: 0.00GB (0%) fs: swap dev: /dev/sda5
Info: Processes: 313 Uptime: 16:37 Memory: 3421.4/15906.9MB Client: Shell (bash) inxi: 2.3.56



UPDATE :


Following Charles' advice, I used performance sampling :


# perf record -a -g sleep 180


...and here's the report :


Samples: 74K of event 'cycles', Event count (approx.): 1043554519767
 Children Self Command Shared Object
- 50.56% 45.86% ffmpeg libavcodec.so.57.107.100 
 - 3.10% 0x4489480000002825 
 0.64% 0x7ffaf24b92f0 
 - 2.12% 0x5f7369007265646f 
 av_default_item_name 
 1.39% 0 
- 44.48% 40.59% ffmpeg libx264.so.152 
 5.78% x264_add8x8_idct_avx2.skip_prologue 
 3.13% x264_add8x8_idct_avx2.skip_prologue 
 2.91% x264_add8x8_idct_avx2.skip_prologue 
 2.31% x264_add8x8_idct_avx.skip_prologue 
 2.03% 0 
 1.78% 0x1 
 1.26% x264_add8x8_idct_avx2.skip_prologue 
 1.09% x264_add8x8_idct_avx.skip_prologue 
 1.06% x264_me_search_ref 
 0.97% x264_add8x8_idct_avx.skip_prologue 
 0.60% x264_me_search_ref 
- 38.01% 0.00% ffmpeg [unknown] 
 4.10% 0 
 - 3.49% 0x4489480000002825 
 0.70% 0x7ffaf24b92f0 
 0.56% 0x7f273ae822f0 
 0.50% 0x7f0c4768b2f0 
 - 2.29% 0x5f7369007265646f 
 av_default_item_name 
 1.99% 0x1 
 10.13% 10.12% ffmpeg [kernel.kallsyms] 
- 3.14% 0.73% ffmpeg libavutil.so.55.78.100 
 2.34% av_default_item_name 
- 1.73% 0.21% ffmpeg libpthread-2.27.so 
 - 0.70% pthread_cond_wait@@GLIBC_2.3.2 
 - 0.62% entry_SYSCALL_64_after_hwframe 
 - 0.62% do_syscall_64 
 - 0.57% __x64_sys_futex 
 0.52% do_futex 
 0.93% 0.89% ffmpeg libc-2.27.so 
- 0.64% 0.64% swapper [kernel.kallsyms] 
 0.63% secondary_startup_64 
 0.21% 0.18% ffmpeg libavfilter.so.6.107.100 
 0.20% 0.11% ffmpeg libavformat.so.57.83.100 
 0.12% 0.11% ffmpeg ffmpeg 
 0.11% 0.00% gnome-terminal- [unknown] 
 0.09% 0.07% ffmpeg libm-2.27.so 
 0.08% 0.07% ffmpeg ld-2.27.so 
 0.04% 0.04% gnome-terminal- libglib-2.0.so.0.5600.4




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FFSERVER - streaming an ASF video as Webm output
30 mai 2014, par Emmanuel BrunetI’m trying to stream an IP webcam ASF live stream to a ffserver to output a webm video format. The server starts successfully but the ffserver commands used to feed the ffserver fails and generates a core dump.
Input stream
$ ffprobe http://account:password@webcam/videostream.asf
Input #0, asf, from 'http://admin:alpha1237@webcam/videostream.asf':
Duration: N/A, start: 0.000000, bitrate: 32 kb/s
Stream #0:0: Video: mjpeg (MJPG / 0x47504A4D), yuvj422p(pc), 640x480, 25 tbr, 1k tbn, 1k tbc
Stream #0:1: Audio: adpcm_ima_wav ([17][0][0][0] / 0x0011), 8000 Hz, 1 channels, s16p, 32 kb/sffserver configuration
my ffserver configuration is :
Port 8091
RTSPPort 554
BindAddress 192.168.1.62
MaxHTTPConnections 1000
MaxClients 100
MaxBandwidth 1000
CustomLog -
<feed>
File /tmp/webcam.ffm
FileMaxSize 500M
ACL allow localhost
ACL allow 192.168.0.0 192.168.255.255
</feed>
<stream> # Output stream URL definition
Feed webcam.ffm # Feed from which to receive video
Format webm
# Audio settings
AudioCodec vorbis
AudioBitRate 64 # Audio bitrate
# Video settings
VideoCodec libvpx
VideoSize 640x480 # Video resolution
VideoFrameRate 25 # Video FPS
AVOptionVideo flags +global_header # Parameters passed to encoder
# (same as ffmpeg command-line parameters)
AVOptionVideo cpu-used 0
AVOptionVideo qmin 10
AVOptionVideo qmax 42
AVOptionVideo quality good
AVOptionAudio flags +global_header
PreRoll 15
StartSendOnKey
# VideoBitRate 32 # Video bitrate
</stream>
<stream>
Format status
# Only allow local people to get the status
ACL allow localhost
ACL allow 192.168.0.0 192.168.255.255
</stream>ffmpeg feed
I run the following command that fails
$ ffmpeg -i http://account:password@webcam/videostream.asf http://192.168.1.62:8091/webcam.ffm
http://192.168.1.62:8091/webcam.ffm
Input #0, asf, from 'http://account:password@webcam/videostream.asf':
Duration: N/A, start: 0.000000, bitrate: 32 kb/s
Stream #0:0: Video: mjpeg (MJPG / 0x47504A4D), yuvj422p(pc), 640x480, 25 tbr, 1k tbn, 1k tbc
Stream #0:1: Audio: adpcm_ima_wav ([17][0][0][0] / 0x0011), 8000 Hz, mono, s16p, 32 kb/s
[swscaler @ 0x36a80c0] deprecated pixel format used, make sure you did set range correctly
Segmentation faultI tryed
$ ffmpeg -i http://account:password@webcam/videostream.asf -pix_fmt yuv420p http://192.168.1.62:8091/webcam.ffmBut it raises the same error.
Thanks for your help
Edit
For an easy testing (I thought), I tried to publish the whole ASF stream as is, meaning connecting the ASF webcam output stream to the ffserver that outputs ASF format too.
And thus with mirrored encoding so I changed the ffserver configuration to...
<stream>
Feed webcam.ffm
Format asf
VideoFrameRate 25
VideoSize 640X480
VideoBitRate 256
VideoBufferSize 1000
VideoGopSize 30
AudioBitRate 32
StartSendOnKey
</stream>
...And the output is now :
Input #0, asf, from 'http://admin:alpha1237@webcam/videostream.asf':
Duration: N/A, start: 0.000000, bitrate: 32 kb/s
Stream #0:0: Video: mjpeg (MJPG / 0x47504A4D), yuvj422p(pc), 640x480, 1k tbr, 1k tbn, 1k tbc
Stream #0:1: Audio: adpcm_ima_wav ([17][0][0][0] / 0x0011), 8000 Hz, mono, s16p, 32 kb/s
[swscaler @ 0x3d620c0] deprecated pixel format used, make sure you did set range correctly
Output #0, ffm, to 'http://192.168.1.62:8091/webcam.ffm':
Metadata:
creation_time : now
encoder : Lavf55.40.100
Stream #0:0: Audio: wmav2, 22050 Hz, mono, fltp, 32 kb/s
Metadata:
encoder : Lavc55.64.100 wmav2
Stream #0:1: Video: msmpeg4v3 (msmpeg4), yuv420p, 640x480, q=2-31, 256 kb/s, 1k fps, 1000k tbn, 1k tbc
Metadata:
Stream mapping:
Stream #0:1 -> #0:0 (adpcm_ima_wav -> wmav2)
Stream #0:0 -> #0:1 (mjpeg -> msmpeg4)
Press [q] to stop, [?] for help
Segmentation faultI can’t even forward the stream.
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Revision ccba289f8d : Fast computation path for forward transform and quantization This commit enable
30 mai 2014, par Jingning HanChanged Paths :
Modify /vp9/common/vp9_rtcd_defs.pl
Modify /vp9/encoder/vp9_block.h
Modify /vp9/encoder/vp9_context_tree.h
Modify /vp9/encoder/vp9_dct.c
Modify /vp9/encoder/vp9_encodeframe.c
Modify /vp9/encoder/vp9_encodemb.c
Modify /vp9/encoder/vp9_encodemb.h
Modify /vp9/encoder/vp9_pickmode.c
Modify /vp9/encoder/vp9_quantize.c
Modify /vp9/encoder/vp9_quantize.h
Modify /vp9/encoder/x86/vp9_dct_sse2.c
Fast computation path for forward transform and quantizationThis commit enables a fast path computational flow for forward
transformation. It checks the sse and variance of prediction
residuals and decides if the quantized coefficients are all
zero, dc only, or more. It then selects the corresponding coding
path in the forward transformation and quantization stage.It is currently enabled in rtc coding mode. Will do it for rd
coding mode next.In speed -6, the runtime for pedestrian_area 1080p at 1000 kbps
goes down from 14234 ms to 13704 ms, i.e., about 4% speed-up.
Overall coding performance for rtc set is changed by -0.18%.Change-Id : I0452da1786d59bc8bcbe0a35fdae9f623d1d44e1
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