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Autres articles (53)
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Mise à jour de la version 0.1 vers 0.2
24 juin 2013, parExplications des différents changements notables lors du passage de la version 0.1 de MediaSPIP à la version 0.3. Quelles sont les nouveautés
Au niveau des dépendances logicielles Utilisation des dernières versions de FFMpeg (>= v1.2.1) ; Installation des dépendances pour Smush ; Installation de MediaInfo et FFprobe pour la récupération des métadonnées ; On n’utilise plus ffmpeg2theora ; On n’installe plus flvtool2 au profit de flvtool++ ; On n’installe plus ffmpeg-php qui n’est plus maintenu au (...) -
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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La sauvegarde automatique de canaux SPIP
1er avril 2010, parDans le cadre de la mise en place d’une plateforme ouverte, il est important pour les hébergeurs de pouvoir disposer de sauvegardes assez régulières pour parer à tout problème éventuel.
Pour réaliser cette tâche on se base sur deux plugins SPIP : Saveauto qui permet une sauvegarde régulière de la base de donnée sous la forme d’un dump mysql (utilisable dans phpmyadmin) mes_fichiers_2 qui permet de réaliser une archive au format zip des données importantes du site (les documents, les éléments (...)
Sur d’autres sites (10242)
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How does ffprobe determine duration ?
10 janvier 2019, par jasongullicksonI’m using
ffprobeto analyze media files stored on a remote server. This seems to work well, but for some files the duration is missing or incorrect (usually longer than it should be). Other times it returns this information accurately, and it doesn’t seem to be related to the media type (codec, etc.).Here’s an example of a command that works :
ffprobe -v quiet -print_format json -show_streams -show_format http://host.com/file.aiff{
"streams": [
{
"index": 0,
"codec_name": "pcm_s16be",
"codec_long_name": "PCM signed 16-bit big-endian",
"codec_type": "audio",
"codec_time_base": "1/44100",
"codec_tag_string": "[0][0][0][0]",
"codec_tag": "0x0000",
"sample_fmt": "s16",
"sample_rate": "44100",
"channels": 2,
"bits_per_sample": 16,
"r_frame_rate": "0/0",
"avg_frame_rate": "0/0",
"time_base": "1/44100",
"start_pts": 0,
"start_time": "0.000000",
"duration_ts": 8494248,
"duration": "192.613333",
"bit_rate": "1411200",
"nb_frames": "8494248",
"disposition": {
"default": 0,
"dub": 0,
"original": 0,
"comment": 0,
"lyrics": 0,
"karaoke": 0,
"forced": 0,
"hearing_impaired": 0,
"visual_impaired": 0,
"clean_effects": 0,
"attached_pic": 0
}
}
],
"format": {
"filename": "http://host.com/file.aiff",
"nb_streams": 1,
"nb_programs": 0,
"format_name": "aiff",
"format_long_name": "Audio IFF",
"start_time": "0.000000",
"duration": "192.613333",
"probe_score": 100
}
}Here’s an example of one that doesn’t :
ffprobe -v quiet -print_format json -show_streams -show_format "http://host.com/file.wav"Which generates this result :
{
"streams": [
{
"index": 0,
"codec_name": "pcm_s16le",
"codec_long_name": "PCM signed 16-bit little-endian",
"codec_type": "audio",
"codec_time_base": "1/44100",
"codec_tag_string": "[1][0][0][0]",
"codec_tag": "0x0001",
"sample_fmt": "s16",
"sample_rate": "44100",
"channels": 2,
"bits_per_sample": 16,
"r_frame_rate": "0/0",
"avg_frame_rate": "0/0",
"time_base": "1/44100",
"bit_rate": "1411200",
"disposition": {
"default": 0,
"dub": 0,
"original": 0,
"comment": 0,
"lyrics": 0,
"karaoke": 0,
"forced": 0,
"hearing_impaired": 0,
"visual_impaired": 0,
"clean_effects": 0,
"attached_pic": 0
}
}
],
"format": {
"filename": "http://host.com/file.wav",
"nb_streams": 1,
"nb_programs": 0,
"format_name": "wav",
"format_long_name": "WAV / WAVE (Waveform Audio)",
"bit_rate": "1411200",
"probe_score": 99
}
}These two examples are different formats, but I’ve seen it work and not work when the format is the same, I just don’t have an example handy.
What I’d like to know is if there is something I can change about the parameters I’m using with
ffprobeto allow the duration to be determined consistently and accurate, or any information I can find as to how ffprobe works so I figure out how I might change the input files, etc. so they work correctly.Alternatively, if there is a different tool that works more reliably (it would need to be an open-source Linux tool) any suggestions or recommendations are welcome.
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How to determine how much of a video stream buffer is filled ?
17 août 2018, par jjulianfOn my Ubuntu machine, I am encoding a video with the x265 codec using
ffmpeg.
Then I want to stream the video from a server to a client.Since the available bandwidth is limited in specific scenarios, I want to observe the moment when the transmission is starting to stutter.
Therefore I want to compare the amount of data being sent at this scenario with the amount of data which is already stored in the buffer (and which was sent a few frames earlier) at the client’s side.
Is there any way to determine how much data is stored in the buffer of the decoding client ? Maybe some
ffmpegcommand for it ?Since I am playing the stream with the VLC player at the client side, is there a
vlc-CLI-command to check the buffer status ?It would be perfect if I could get the current fill of the buffer for every second so that I can graph it like this :
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ffmpeg - Determine what parameters
27 juin 2018, par AdmiralJonBI’ve got a video file that I’m trying to determine what parameters I can use to reproduce the encoding with ffmpeg.
Here’s the ffprobe of the particular stream in question.
Input #0, mov,mp4,m4a,3gp,3g2,mj2, from 'video.mp4': Metadata:
major_brand : isom
minor_version : 512
compatible_brands: isomiso2avc1mp41
encoder : Lavf57.51.107
Duration: 00:05:02.84, start: 0.000000, bitrate: 4324 kb/s
Stream #0:0(und): Video: h264 (Main) (avc1 / 0x31637661), yuvj420p(pc, bt709), 1920x1080 [SAR 1:1 DAR 16:9], 4323 kb/s, 25 fps, 25 tbr, 1200k tbn, 2400k tbc (default)
Metadata:
handler_name : VideoHandlerThe key part is that I’m noticing that the bitrate is quite low at 4324 kb/s, but this is actually an incredibly high quality video. To approach this sort of quality, I’ve only been able to make videos at 40000 kb/s (which is a huge increase in filesize). I also notice that it mentions yuvj420p which is an image format, but I have no idea what parameters with ffmpeg could produce that image format (if this at all would make a difference).
Would appreciate any help I can get.
Edit :
Here’s the output based on the comment below :
[STREAM]
index=0
codec_name=h264
codec_long_name=H.264 / AVC / MPEG-4 AVC / MPEG-4 part 10
profile=Main
codec_type=video
codec_time_base=123187/3701760
codec_tag_string=avc1
codec_tag=0x31637661
width=1920
height=1080
coded_width=1920
coded_height=1080
has_b_frames=0
sample_aspect_ratio=1:1
display_aspect_ratio=16:9
pix_fmt=yuvj420p
level=41
color_range=pc
color_space=bt709
color_transfer=bt709
color_primaries=bt709
chroma_location=center
field_order=unknown
timecode=N/A
refs=1
is_avc=true
nal_length_size=4
id=N/A
r_frame_rate=15/1
avg_frame_rate=1850880/123187
time_base=1/15360
start_pts=0
start_time=0.000000
duration_ts=246374
duration=16.039974
bit_rate=13795677
max_bit_rate=N/A
bits_per_raw_sample=8
nb_frames=241
nb_read_frames=N/A
nb_read_packets=N/A
DISPOSITION:default=1
DISPOSITION:dub=0
DISPOSITION:original=0
DISPOSITION:comment=0
DISPOSITION:lyrics=0
DISPOSITION:karaoke=0
DISPOSITION:forced=0
DISPOSITION:hearing_impaired=0
DISPOSITION:visual_impaired=0
DISPOSITION:clean_effects=0
DISPOSITION:attached_pic=0
DISPOSITION:timed_thumbnails=0
TAG:language=und
TAG:handler_name=VideoHandler
[/STREAM]Edit 2 :
Here’s information from mediainfo
Video
ID : 1
Format : AVC
Format/Info : Advanced Video Codec
Format profile : Main@L4.1
Format settings, CABAC : Yes
Format settings, RefFrames : 1 frame
Format settings, GOP : M=1, N=32
Codec ID : avc1
Codec ID/Info : Advanced Video Coding
Duration : 5 min 2 s
Bit rate : 4 323 kb/s
Width : 1 920 pixels
Height : 1 080 pixels
Display aspect ratio : 16:9
Frame rate mode : Constant
Frame rate : 25.000 FPS
Color space : YUV
Chroma subsampling : 4:2:0
Bit depth : 8 bits
Scan type : Progressive
Bits/(Pixel*Frame) : 0.083
Stream size : 156 MiB (100%)
Color range : Full
Color primaries : BT.709
Transfer characteristics : BT.709
Matrix coefficients : BT.709
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