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Organiser par catégorie
17 mai 2013, parDans MédiaSPIP, une rubrique a 2 noms : catégorie et rubrique.
Les différents documents stockés dans MédiaSPIP peuvent être rangés dans différentes catégories. On peut créer une catégorie en cliquant sur "publier une catégorie" dans le menu publier en haut à droite ( après authentification ). Une catégorie peut être rangée dans une autre catégorie aussi ce qui fait qu’on peut construire une arborescence de catégories.
Lors de la publication prochaine d’un document, la nouvelle catégorie créée sera proposée (...) -
Récupération d’informations sur le site maître à l’installation d’une instance
26 novembre 2010, parUtilité
Sur le site principal, une instance de mutualisation est définie par plusieurs choses : Les données dans la table spip_mutus ; Son logo ; Son auteur principal (id_admin dans la table spip_mutus correspondant à un id_auteur de la table spip_auteurs)qui sera le seul à pouvoir créer définitivement l’instance de mutualisation ;
Il peut donc être tout à fait judicieux de vouloir récupérer certaines de ces informations afin de compléter l’installation d’une instance pour, par exemple : récupérer le (...) -
Le plugin : Podcasts.
14 juillet 2010, parLe problème du podcasting est à nouveau un problème révélateur de la normalisation des transports de données sur Internet.
Deux formats intéressants existent : Celui développé par Apple, très axé sur l’utilisation d’iTunes dont la SPEC est ici ; Le format "Media RSS Module" qui est plus "libre" notamment soutenu par Yahoo et le logiciel Miro ;
Types de fichiers supportés dans les flux
Le format d’Apple n’autorise que les formats suivants dans ses flux : .mp3 audio/mpeg .m4a audio/x-m4a .mp4 (...)
Sur d’autres sites (3258)
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Ffmpeg video time not selectable in VLC and other players
22 avril 2020, par ExpressingxWe are using ffmpeg with C# (doxygen ?) to record video from a camera. The problem is that the video start time, or frame timestamps or I don't know honestly what is wrong but results to not 'selectable' time in some players. WebPlayer and VLC, Windows Media Player is fine.



The output of
ffprobe -show_format -show_streams myMp4File.mp4



index=0
codec_name=h264
codec_long_name=H.264 / AVC / MPEG-4 AVC / MPEG-4 part 10
profile=High
codec_type=video
codec_time_base=715183/42501120
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=yuv420p
level=42
color_range=N/A
color_space=unknown
color_transfer=unknown
color_primaries=unknown
chroma_location=left
field_order=unknown
timecode=N/A
refs=1
is_avc=true
nal_length_size=4
id=N/A
r_frame_rate=30/1
avg_frame_rate=21250560/715183
time_base=1/15360
start_pts=903093780
start_time=58795.167969
duration_ts=904524149
duration=58888.290951
bit_rate=14900396
max_bit_rate=N/A
bits_per_raw_sample=8
nb_frames=2767
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]
[FORMAT]
filename=C:\myMp4File.mp4
nb_streams=1
nb_programs=0
format_name=mov,mp4,m4a,3gp,3g2,mj2
format_long_name=QuickTime / MOV
start_time=58795.167969
duration=93.123000
size=173478228
bit_rate=14903147
probe_score=100
TAG:major_brand=isom
TAG:minor_version=512
TAG:compatible_brands=isomiso2avc1mp41
TAG:encoder=Lavf57.47.101










Not a guru in ffmpeg and video streams, but if someone can point to what could be wrong ? I believe the problem is
start_time
but..

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Streaming video .mp4 H.264 baseline not working on some videos [duplicate]
8 janvier 2019, par D. B.This question already has an answer here :
I use server to stream recorder videos on Android phones and play them in Android app later. However I noticed that I am not able to play all videos, I used ffmpeg to see if there is any difference in recorded videos and where the issue might be.
That is an example of loading and playing video :Input #0, mov,mp4,m4a,3gp,3g2,mj2, from 'w1.mp4':
Metadata:
major_brand : mp42
minor_version : 0
compatible_brands: isommp42
creation_time : 2019-01-07T15:38:52.000000Z
com.android.version: 8.1.0
Duration: 00:00:04.94, start: 0.000000, bitrate: 5003 kb/s
Stream #0:0(eng): Video: h264 (Baseline) (avc1 / 0x31637661), yuv420p(tv, smpte170m/bt470bg/smpte170m), 720x480, 4951 kb/s, SAR 1:1 DAR 3:2, 27.71 fps, 30 tbr, 90k tbn, 180k tbc (default)
Metadata:
rotate : 90
creation_time : 2019-01-07T15:38:52.000000Z
handler_name : VideoHandle
Side data:
displaymatrix: rotation of -90.00 degrees
Stream #0:1(eng): Audio: aac (LC) (mp4a / 0x6134706D), 8000 Hz, mono, fltp, 48 kb/s (default)
Metadata:
creation_time : 2019-01-07T15:38:52.000000Z
handler_name : SoundHandle
"streams": [
{
"index": 0,
"codec_name": "h264",
"codec_long_name": "H.264 / AVC / MPEG-4 AVC / MPEG-4 part 10",
"profile": "Baseline",
"codec_type": "video",
"codec_time_base": "444929/24660000",
"codec_tag_string": "avc1",
"codec_tag": "0x31637661",
"width": 720,
"height": 480,
"coded_width": 720,
"coded_height": 480,
"has_b_frames": 0,
"sample_aspect_ratio": "1:1",
"display_aspect_ratio": "3:2",
"pix_fmt": "yuv420p",
"level": 30,
"color_range": "tv",
"color_space": "smpte170m",
"color_transfer": "smpte170m",
"color_primaries": "bt470bg",
"chroma_location": "left",
"refs": 1,
"is_avc": "true",
"nal_length_size": "4",
"r_frame_rate": "30/1",
"avg_frame_rate": "12330000/444929",
"time_base": "1/90000",
"start_pts": 0,
"start_time": "0.000000",
"duration_ts": 444929,
"duration": "4.943656",
"bit_rate": "4951506",
"bits_per_raw_sample": "8",
"nb_frames": "137",
"disposition": {
"default": 1,
"dub": 0,
"original": 0,
"comment": 0,
"lyrics": 0,
"karaoke": 0,
"forced": 0,
"hearing_impaired": 0,
"visual_impaired": 0,
"clean_effects": 0,
"attached_pic": 0,
"timed_thumbnails": 0
},
"tags": {
"rotate": "90",
"creation_time": "2019-01-07T15:38:52.000000Z",
"language": "eng",
"handler_name": "VideoHandle"
},
"side_data_list": [
{
"side_data_type": "Display Matrix",
"displaymatrix": "\n00000000: 0 65536 0\n00000001: -65536 0 0\n00000002: 0 0 1073741824\n",
"rotation": -90
}
]
}
]
}Next is the example of not working video :
[mov,mp4,m4a,3gp,3g2,mj2 @ 000001ea0adcd700] sample aspect ratio already set to 1:1, ignoring 'pasp' atom (65536:65536)
Input #0, mov,mp4,m4a,3gp,3g2,mj2, from 'notworking.mp4':
Metadata:
major_brand : mp42
minor_version : 0
compatible_brands: isommp42
creation_time : 2018-12-30T14:20:23.000000Z
com.android.version: 7.0
Duration: 00:00:10.16, start: 0.000000, bitrate: 5240 kb/s
Stream #0:0(eng): Video: h264 (Baseline) (avc1 / 0x31637661), yuv420p(tv, smpte170m/bt470bg/smpte170m), 720x480, 5223 kb/s, SAR 1:1 DAR 3:2, 29.30 fps, 59.94 tbr, 90k tbn, 180k tbc (default)
Metadata:
rotate : 90
creation_time : 2018-12-30T14:20:23.000000Z
handler_name : VideoHandle
Side data:
displaymatrix: rotation of -90.00 degrees
Stream #0:1(eng): Audio: aac (LC) (mp4a / 0x6134706D), 8000 Hz, mono, fltp, 12 kb/s (default)
Metadata:
creation_time : 2018-12-30T14:20:23.000000Z
handler_name : SoundHandle
"streams": [
{
"index": 0,
"codec_name": "h264",
"codec_long_name": "H.264 / AVC / MPEG-4 AVC / MPEG-4 part 10",
"profile": "Baseline",
"codec_type": "video",
"codec_time_base": "20751/1216000",
"codec_tag_string": "avc1",
"codec_tag": "0x31637661",
"width": 720,
"height": 480,
"coded_width": 720,
"coded_height": 480,
"has_b_frames": 0,
"sample_aspect_ratio": "1:1",
"display_aspect_ratio": "3:2",
"pix_fmt": "yuv420p",
"level": 30,
"color_range": "tv",
"color_space": "smpte170m",
"color_transfer": "smpte170m",
"color_primaries": "bt470bg",
"chroma_location": "left",
"refs": 1,
"is_avc": "true",
"nal_length_size": "4",
"r_frame_rate": "60000/1001",
"avg_frame_rate": "608000/20751",
"time_base": "1/90000",
"start_pts": 0,
"start_time": "0.000000",
"duration_ts": 914271,
"duration": "10.158567",
"bit_rate": "5223363",
"bits_per_raw_sample": "8",
"nb_frames": "304",
"disposition": {
"default": 1,
"dub": 0,
"original": 0,
"comment": 0,
"lyrics": 0,
"karaoke": 0,
"forced": 0,
"hearing_impaired": 0,
"visual_impaired": 0,
"clean_effects": 0,
"attached_pic": 0,
"timed_thumbnails": 0
},
"tags": {
"rotate": "90",
"creation_time": "2018-12-30T14:20:23.000000Z",
"language": "eng",
"handler_name": "VideoHandle"
},
"side_data_list": [
{
"side_data_type": "Display Matrix",
"displaymatrix": "\n00000000: 0 65536 0\n00000001: -65536 0 0\n00000002: 0 0 1073741824\n",
"rotation": -90
}
]
}
]
}I cannot see any difference in the videos characteristics. Both are baseline H.264.
Both videos are playing in chrome when I access them via direct links, the problem is on android versions 6, 7, 8.
There is strange thing because when I downloaded that not loading video directly and put in the android app to raw folder and played it directly everything worked perfectly.
I checked if the problem was bandwidth, so I uploaded bigger video about 12Mbs, mp4 as well H.264 Main and then streamed it to the app and it worked like a charm. So I suspect that the issue might be with recording bigger files within my android app.
To stream video I only use MediaPlayer.That is an example of the video I uploaded and later streamed :
Input #0, mov,mp4,m4a,3gp,3g2,mj2, from '123456.mp4':
Metadata:
major_brand : mp42
minor_version : 0
compatible_brands: isommp42
creation_time : 2018-01-30T06:50:54.000000Z
Duration: 00:02:29.16, start: 0.000000, bitrate: 700 kb/s
Stream #0:0(und): Video: h264 (Main) (avc1 / 0x31637661), yuv420p(tv, bt709), 1280x720 [SAR 1:1 DAR 16:9], 571 kb/s, 25 fps, 25 tbr, 90k tbn, 50 tbc (default)
Metadata:
creation_time : 2018-01-30T06:50:54.000000Z
handler_name : ISO Media file. Created on: 01/29/2018.
Stream #0:1(und): Audio: aac (LC) (mp4a / 0x6134706D), 44100 Hz, stereo, fltp, 125 kb/s (default)
Metadata:
creation_time : 2018-01-30T06:50:54.000000Z
handler_name : ISO Media file. Created on: 01/29/2018.
"streams": [
{
"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": "1/50",
"codec_tag_string": "avc1",
"codec_tag": "0x31637661",
"width": 1280,
"height": 720,
"coded_width": 1280,
"coded_height": 720,
"has_b_frames": 1,
"sample_aspect_ratio": "1:1",
"display_aspect_ratio": "16:9",
"pix_fmt": "yuv420p",
"level": 31,
"color_range": "tv",
"color_space": "bt709",
"color_transfer": "bt709",
"color_primaries": "bt709",
"chroma_location": "left",
"refs": 1,
"is_avc": "true",
"nal_length_size": "4",
"r_frame_rate": "25/1",
"avg_frame_rate": "25/1",
"time_base": "1/90000",
"start_pts": 0,
"start_time": "0.000000",
"duration_ts": 13424400,
"duration": "149.160000",
"bit_rate": "571258",
"bits_per_raw_sample": "8",
"nb_frames": "3729",
"disposition": {
"default": 1,
"dub": 0,
"original": 0,
"comment": 0,
"lyrics": 0,
"karaoke": 0,
"forced": 0,
"hearing_impaired": 0,
"visual_impaired": 0,
"clean_effects": 0,
"attached_pic": 0,
"timed_thumbnails": 0
},
"tags": {
"creation_time": "2018-01-30T06:50:54.000000Z",
"language": "und",
"handler_name": "ISO Media file. Created on: 01/29/2018."
}
}
]
}
Is there any chance that my hosting provider uses some kind of software that can manipulate data that is on the server?I also check manually other videos from different websites by inserting links manually in the code to check if MediaPlayer works correctly and every video was playing.
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Basic "pass-through" use of FFmpegReader/FFmpegWriter in scikit-video
6 février 2021, par JonathanZ supports MonicaCI am starting to use scikit-video and am having trouble writing files. I have reduced the problem to the simplest possible example


vid_file = "6710185719062326259_stamp_25pct.mp4"
output_file = "out_temp3.mp4"
reader = skvideo.io.FFmpegReader(vid_file)
writer = skvideo.io.FFmpegWriter(output_file)
for frame in reader.nextFrame():
 writer.writeFrame(frame)
writer.close()



I'm playing the files in VLC, and the
vid_file
is valid but the output file, though playable, is mostly big green blocks (though I can discern some details from the original video in it).

My goal, or course, is to do "interesting" manipulations of the frame before I write it out, but I need to get the "no modifications" version working correctly first. I'm also going to be using this on large files, so the
vread/vwrite
functions that process an entire file at once are not appropriate.

I'm guessing I need to set the appropriate values in the
outputdict
parameter for the FFmpegWriter, but there are so many that I don't know where to start. I have tried

writer = skvideo.io.FFmpegWriter(output_file, outputdict={'-crf': '0', '-pix_fmt': 'rgb24'})



(
-crf 0
to suppress any compression,-pixfmt rgb24
as that's what FFmpegReader says it delivers by default, but these don't work either.

Any ideas on how to make this work ?


Here's the
skvideo.io.ffprobe
video information for the input file.

{
 "@index": "0",
 "@codec_name": "h264",
 "@codec_long_name": "H.264 / AVC / MPEG-4 AVC / MPEG-4 part 10",
 "@profile": "High",
 "@codec_type": "video",
 "@codec_time_base": "1/30",
 "@codec_tag_string": "avc1",
 "@codec_tag": "0x31637661",
 "@width": "480",
 "@height": "270",
 "@coded_width": "480",
 "@coded_height": "272",
 "@has_b_frames": "2",
 "@pix_fmt": "yuv420p",
 "@level": "21",
 "@chroma_location": "left",
 "@refs": "1",
 "@is_avc": "true",
 "@nal_length_size": "4",
 "@r_frame_rate": "15/1",
 "@avg_frame_rate": "15/1",
 "@time_base": "1/15360",
 "@start_pts": "0",
 "@start_time": "0.000000",
 "@duration_ts": "122880",
 "@duration": "8.000000",
 "@bit_rate": "183806",
 "@bits_per_raw_sample": "8",
 "@nb_frames": "120",
 "disposition": {
 "@default": "1",
 "@dub": "0",
 "@original": "0",
 "@comment": "0",
 "@lyrics": "0",
 "@karaoke": "0",
 "@forced": "0",
 "@hearing_impaired": "0",
 "@visual_impaired": "0",
 "@clean_effects": "0",
 "@attached_pic": "0",
 "@timed_thumbnails": "0"
 },
 "tag": [
 {
 "@key": "language",
 "@value": "und"
 },
 {
 "@key": "handler_name",
 "@value": "VideoHandler"
 }
 ]
}



I will mention that when I ffprobe the output file the only differences I see are 1) the timing data is different, which isn't surprising, and 2) the output file has


"@has_b_frames": "0",
 "@pix_fmt": "yuv444p",



I'm pretty confident the reader is working okay, because if I write out the data with


skimage.io.imsave('x.png', frame, check_contrast=False)



it looks good.