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Médias (10)
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Demon Seed
26 septembre 2011, par
Mis à jour : Septembre 2011
Langue : English
Type : Audio
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Demon seed (wav version)
26 septembre 2011, par
Mis à jour : Avril 2013
Langue : English
Type : Audio
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The four of us are dying (wav version)
26 septembre 2011, par
Mis à jour : Avril 2013
Langue : English
Type : Audio
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Corona radiata (wav version)
26 septembre 2011, par
Mis à jour : Avril 2013
Langue : English
Type : Audio
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Lights in the sky (wav version)
26 septembre 2011, par
Mis à jour : Avril 2013
Langue : English
Type : Audio
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Head down (wav version)
26 septembre 2011, par
Mis à jour : Avril 2013
Langue : English
Type : Audio
Autres articles (38)
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Support audio et vidéo HTML5
10 avril 2011MediaSPIP utilise les balises HTML5 video et audio pour la lecture de documents multimedia en profitant des dernières innovations du W3C supportées par les navigateurs modernes.
Pour les navigateurs plus anciens, le lecteur flash Flowplayer est utilisé.
Le lecteur HTML5 utilisé a été spécifiquement créé pour MediaSPIP : il est complètement modifiable graphiquement pour correspondre à un thème choisi.
Ces technologies permettent de distribuer vidéo et son à la fois sur des ordinateurs conventionnels (...) -
HTML5 audio and video support
13 avril 2011, parMediaSPIP uses HTML5 video and audio tags to play multimedia files, taking advantage of the latest W3C innovations supported by modern browsers.
The MediaSPIP player used has been created specifically for MediaSPIP and can be easily adapted to fit in with a specific theme.
For older browsers the Flowplayer flash fallback is used.
MediaSPIP allows for media playback on major mobile platforms with the above (...) -
De l’upload à la vidéo finale [version standalone]
31 janvier 2010, parLe chemin d’un document audio ou vidéo dans SPIPMotion est divisé en trois étapes distinctes.
Upload et récupération d’informations de la vidéo source
Dans un premier temps, il est nécessaire de créer un article SPIP et de lui joindre le document vidéo "source".
Au moment où ce document est joint à l’article, deux actions supplémentaires au comportement normal sont exécutées : La récupération des informations techniques des flux audio et video du fichier ; La génération d’une vignette : extraction d’une (...)
Sur d’autres sites (4374)
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Why use sysconf(_SC_NPROCESSORS_CONF) to get the number of CPU cores in x264 ?
5 novembre 2017, par bknievenI find x264 use sysconf(_SC_NPROCESSORS_CONF) instead of sysconf(SC_NPROCESSORS_ONLN) to get the number of CPU cores.
Here is the code snippet in x264/common/cpu.c :
...
#ifdef __ANDROID__
// Android NDK does not expose sched_getaffinity
return sysconf( _SC_NPROCESSORS_CONF );
#else
...
....And I find the difference between _SC_NPROCESSORS_CONF and _SC_NPROCESSORS_ONLN in this manual :
sysconf (_SC_NPROCESSORS_CONF) which returns the number of processors
the operating system configured. But it might be possible for the
operating system to disable individual processors and so the call
sysconf (_SC_NPROCESSORS_ONLN) returns the number of processors which
are currently online (i.e., available).I have two questions :
- What is the difference between "the number of processors the operating system configured" and "the number of processors which are currently online" ?
- Why x264 use _SC_NPROCESSORS_CONF in Android to get the number of CPU cores ?
-
Changing video color to Black&White and Blue and RGB [on hold]
2 janvier 2016, par drorAlfasiI am using Dranger - ffmpeg and SDL Tutorial and I am trying to change video format to RGB, then when pressing W key transfer to BW and then on C to bring it back to colour.
After bringing it back to colour while pressing on B button the stream need to change to Blue colour.
I can’t success to convert it to RGB.
Any help ?I am using tutorial 07 of Dranger.
Link to Dranger C code -
FFMPEG segment creates black frame in the beginning - and key_frame looks offset [closed]
30 septembre 2022, par jackyrooI'm trying to split a video using ffmpeg segment :


ffmpeg -r 60 -accurate_seek -I input.mov -map 0:a? -map 0:v? -codec copy -reset_timestamps 1 -map_metadata 0 -avoid_negative_ts 1 -f segment output_%%03d.mov -y -loglevel debug


The problem with this approach is that the first split segment has 2 black frames at the beginning, while the consecutive ones are fine.


I cannot figure out why, and I'm genuinely lost in this process.


I've also tried specifying -force_key_frames but it makes no difference at all.


Then I found something interesting by comparing keyframes of the original video and the first split chunk using this command :


ffprobe -select_streams v -skip_frame nokey -show_frames -v quiet input.mov


Original Video KeyFrames
The first keyframe of the original video looks fine :


[FRAME]
media_type=video
stream_index=0
key_frame=1
pts=0
pts_time=0.000000
pkt_dts=127488
pkt_dts_time=8.300000
best_effort_timestamp=0
best_effort_timestamp_time=0.000000
pkt_duration=256
pkt_duration_time=0.016667
duration=256
duration_time=0.016667
pkt_pos=40
pkt_size=128838
width=1420
height=2000
pix_fmt=yuv420p
sample_aspect_ratio=N/A
pict_type=I
coded_picture_number=0
display_picture_number=0
interlaced_frame=0
top_field_first=0
repeat_pict=0
color_range=unknown
color_space=unknown
color_primaries=unknown
color_transfer=unknown
chroma_location=left
[SIDE_DATA]
side_data_type=H.26[45] User Data Unregistered SEI message
[/SIDE_DATA]
[/FRAME]



Split Video - First Chunk Keyframes


On the other hand, it seems like the first keyframe of the chunk (the one with the two added black frames in the beginning) gets shifted !


[FRAME]
media_type=video
stream_index=1
key_frame=1
pts=507
pts_time=0.033008
pkt_dts=N/A
pkt_dts_time=N/A
best_effort_timestamp=507
best_effort_timestamp_time=0.033008
pkt_duration=256
pkt_duration_time=0.016667
duration=256
duration_time=0.016667
pkt_pos=40
pkt_size=128838
width=1420
height=2000
pix_fmt=yuv420p
sample_aspect_ratio=N/A
pict_type=I
coded_picture_number=0
display_picture_number=0
interlaced_frame=0
top_field_first=0
repeat_pict=0
color_range=unknown
color_space=unknown
color_primaries=unknown
color_transfer=unknown
chroma_location=left
[SIDE_DATA]
side_data_type=H.26[45] User Data Unregistered SEI message
[/SIDE_DATA]
[/FRAME]



Might this be the cause of the two black frames at the beginning ?


The following is the first (and only) keyframe of the second chunk, and it looks fine :


[FRAME]
media_type=video
stream_index=1
key_frame=1
pts=0
pts_time=0.000000
pkt_dts=N/A
pkt_dts_time=N/A
best_effort_timestamp=0
best_effort_timestamp_time=0.000000
pkt_duration=256
pkt_duration_time=0.016667
duration=256
duration_time=0.016667
pkt_pos=40
pkt_size=158598
width=1420
height=2000
pix_fmt=yuv420p
sample_aspect_ratio=N/A
pict_type=I
coded_picture_number=0
display_picture_number=0
interlaced_frame=0
top_field_first=0
repeat_pict=0
color_range=unknown
color_space=unknown
color_primaries=unknown
color_transfer=unknown
chroma_location=left
[/FRAME]



Please help me spreading some light over this...


Thanks !