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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 (...) -
Qualité du média après traitement
21 juin 2013, parLe bon réglage du logiciel qui traite les média est important pour un équilibre entre les partis ( bande passante de l’hébergeur, qualité du média pour le rédacteur et le visiteur, accessibilité pour le visiteur ). Comment régler la qualité de son média ?
Plus la qualité du média est importante, plus la bande passante sera utilisée. Le visiteur avec une connexion internet à petit débit devra attendre plus longtemps. Inversement plus, la qualité du média est pauvre et donc le média devient dégradé voire (...) -
Ecrire une actualité
21 juin 2013, parPrésentez les changements dans votre MédiaSPIP ou les actualités de vos projets sur votre MédiaSPIP grâce à la rubrique actualités.
Dans le thème par défaut spipeo de MédiaSPIP, les actualités sont affichées en bas de la page principale sous les éditoriaux.
Vous pouvez personnaliser le formulaire de création d’une actualité.
Formulaire de création d’une actualité Dans le cas d’un document de type actualité, les champs proposés par défaut sont : Date de publication ( personnaliser la date de publication ) (...)
Sur d’autres sites (2698)
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Converting `webm` to `mov` format using ffmpeg loses transparency - how can I keep it ?
10 mars 2023, par M.A ShahbaziI am trying to convert a
webmvideo tomovformat without losing quality and transparency using the following command :

ffmpeg -c:v libvpx-vp9 -i input.webm ouput.mov


The video gets converted, but it loses transparency and the background of video is black.


I also tried the following command :


ffmpeg -c:v png -i input.webm output.mov


But it gives me the following error output :


libavutil 58. 3.100 / 58. 3.100
 libavcodec 60. 4.100 / 60. 4.100
 libavformat 60. 4.100 / 60. 4.100
 libavdevice 60. 2.100 / 60. 2.100
 libavfilter 9. 4.100 / 9. 4.100
 libswscale 7. 2.100 / 7. 2.100
 libswresample 4. 11.100 / 4. 11.100
 libpostproc 57. 2.100 / 57. 2.100
[png @ 0000028041ca7000] Invalid PNG signature 0x824983420031F031.
[matroska,webm @ 0000028041c91240] Could not find codec parameters for stream 0 (Video: png, none(pc, progressive), 800x800): unspecified pixel format
Consider increasing the value for the 'analyzeduration' (0) and 'probesize' (5000000) options
Input #0, matroska,webm, from 'hero.webm':
 Metadata:
 COMPATIBLE_BRANDS: qt
 creation_time : 2023-02-23T10:43:46.703800Z
 MAJOR_BRAND : qt
 MINOR_VERSION : 537199360
 ENCODER : Lavf59.35.100
 Duration: 00:00:09.00, start: 0.000000, bitrate: 1378 kb/s
 Stream #0:0: Video: png, none(pc, progressive), 800x800, SAR 1:1 DAR 1:1, 24 fps, 24 tbr, 1k tbn
 Metadata:
 alpha_mode : 1
 ENCODER : Lavc59.56.100 libvpx-vp9
 DURATION : 00:00:09.000000000
Stream mapping:
 Stream #0:0 -> #0:0 (png (native) -> h264 (libx264))
Press [q] to stop, [?] for help
[png @ 0000028041ca7680] Invalid PNG signature 0x824983420031F031.
Error while decoding stream #0:0: Invalid data found when processing input
Cannot determine format of input stream 0:0 after EOF
Error marking filters as finished
Conversion failed!


How can I maintain transparency when converting from
webmtomovformat ?

Here's the video info in case it can be helpful :


{
 "streams": [
 {
 "index": 0,
 "codec_name": "vp9",
 "codec_long_name": "Google VP9",
 "profile": "Profile 0",
 "codec_type": "video",
 "codec_tag_string": "[0][0][0][0]",
 "codec_tag": "0x0000",
 "width": 800,
 "height": 800,
 "coded_width": 800,
 "coded_height": 800,
 "closed_captions": 0,
 "film_grain": 0,
 "has_b_frames": 0,
 "sample_aspect_ratio": "1:1",
 "display_aspect_ratio": "1:1",
 "pix_fmt": "yuv420p",
 "level": -99,
 "color_range": "tv",
 "field_order": "progressive",
 "refs": 1,
 "r_frame_rate": "24/1",
 "avg_frame_rate": "24/1",
 "time_base": "1/1000",
 "start_pts": 0,
 "start_time": "0.000000",
 "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,
 "timed_thumbnails": 0,
 "captions": 0,
 "descriptions": 0,
 "metadata": 0,
 "dependent": 0,
 "still_image": 0
 },
 "tags": {
 "alpha_mode": "1",
 "ENCODER": "Lavc59.56.100 libvpx-vp9",
 "DURATION": "00:00:09.000000000"
 }
 }
 ],
 "format": {
 "filename": ".\\hero.webm",
 "nb_streams": 1,
 "nb_programs": 0,
 "format_name": "matroska,webm",
 "format_long_name": "Matroska / WebM",
 "start_time": "0.000000",
 "duration": "9.000000",
 "size": "1550466",
 "bit_rate": "1378192",
 "probe_score": 100,
 "tags": {
 "COMPATIBLE_BRANDS": "qt ",
 "creation_time": "2023-02-23T10:43:46.703800Z",
 "MAJOR_BRAND": "qt ",
 "MINOR_VERSION": "537199360",
 "ENCODER": "Lavf59.35.100"
 }
 }
}


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FFMPEG failing when calling with a offset
8 septembre 2020, par sarath chandraI am new to FFMPEG. Sorry if this question is too basic.


I want to cut a sample sample of 30 sec from time 30sec. But when i execute a below command it was failing with exception


cmd


ffmpeg -loglevel debug -ss 00:00:30.000 -t 30 -i source.flac -acodec libmp3lame -ab 64k -ac 2 -ar 22050 -y -vn target.mp3


Output


ur_dts is invalid st:0 (0) [init:0 i_done:0 finish:0] (this is harmless if it occurs once at the start per stream)
[flac @ 0x7f9603006200] blocksize 32768 > 4096
cur_dts is invalid st:0 (0) [init:0 i_done:0 finish:0] (this is harmless if it occurs once at the start per stream)
[flac @ 0x7f9603006200] decode_frame() failed
Error while decoding stream #0:0: Invalid data found when processing input
cur_dts is invalid st:0 (0) [init:0 i_done:0 finish:0] (this is harmless if it occurs once at the start per stream)
 Last message repeated 1 times
[graph_0_in_0_0 @ 0x7f960241ab00] Setting 'time_base' to value '1/0'
[abuffer @ 0x7f960241ac00] Value inf for parameter 'time_base' out of range [0 - 2.14748e+09]
 Last message repeated 1 times
[graph_0_in_0_0 @ 0x7f960241ab00] Setting 'sample_rate' to value '0'
[graph_0_in_0_0 @ 0x7f960241ab00] Setting 'sample_fmt' to value 's32'
[graph_0_in_0_0 @ 0x7f960241ab00] Setting 'channel_layout' to value '0x4'
[abuffer @ 0x7f960241ac00] Value inf for parameter 'time_base' out of range [0 - 2.14748e+09]
 Last message repeated 1 times



But when i changed the offset zero seconds it was successfully transcoding.


cmd


ffmpeg -loglevel debug -ss 00:00:00.000 -t 30 -i source.flac -acodec libmp3lame -ab 64k -ac 2 -ar 22050 -y -vn target.mp3 


Output


Output file #0 (target2.mp3):
 Output stream #0:0 (audio): 2680 frames encoded (1543500 samples); 2682 packets muxed (560483 bytes); 
 Total: 2682 packets (560483 bytes) muxed
756 frames successfully decoded, 0 decoding errors
[AVIOContext @ 0x7f9050d05980] Statistics: 2 seeks, 4 writeouts
[AVIOContext @ 0x7f9050e18b00] Statistics: 12320768 bytes read, 2 seeks


I check the mediainfo didn't find anything


{
 "index": "0",
 "codec_name": "flac",
 "codec_long_name": "FLAC (Free Lossless Audio Codec)",
 "profile": "unknown",
 "codec_type": "audio",
 "codec_time_base": "1/44100",
 "codec_tag_string": "[0][0][0][0]",
 "codec_tag": "0x0000",
 "sample_fmt": "s32",
 "sample_rate": "44100",
 "channels": "2",
 "channel_layout": "stereo",
 "bits_per_sample": "0",
 "id": "N/A",
 "r_frame_rate": "0/0",
 "avg_frame_rate": "0/0",
 "time_base": "1/44100",
 "start_pts": "0",
 "start_time": "0.000000",
 "duration_ts": "9784915",
 "duration": "221.880159",
 "bit_rate": "1347288",
 "max_bit_rate": "N/A",
 "bits_per_raw_sample": "24",
 "nb_frames": "N/A",
 "nb_read_frames": "N/A",
 "nb_read_packets": "N/A",
 "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",
 "timed_thumbnails": "0"
 },
 "filename": "source.flac",
 "nb_streams": "1",
 "nb_programs": "0",
 "format_name": "flac",
 "format_long_name": "raw FLAC",
 "size": "37367072",
 "probe_score": "100"
}


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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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