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Rennes Emotion Map 2010-11
19 octobre 2011, par
Mis à jour : Juillet 2013
Langue : français
Type : Texte
Autres articles (82)
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Use, discuss, criticize
13 avril 2011, parTalk to people directly involved in MediaSPIP’s development, or to people around you who could use MediaSPIP to share, enhance or develop their creative projects.
The bigger the community, the more MediaSPIP’s potential will be explored and the faster the software will evolve.
A discussion list is available for all exchanges between users. -
Installation en mode ferme
4 février 2011, parLe mode ferme permet d’héberger plusieurs sites de type MediaSPIP en n’installant qu’une seule fois son noyau fonctionnel.
C’est la méthode que nous utilisons sur cette même plateforme.
L’utilisation en mode ferme nécessite de connaïtre un peu le mécanisme de SPIP contrairement à la version standalone qui ne nécessite pas réellement de connaissances spécifique puisque l’espace privé habituel de SPIP n’est plus utilisé.
Dans un premier temps, vous devez avoir installé les mêmes fichiers que l’installation (...) -
MediaSPIP en mode privé (Intranet)
17 septembre 2013, parÀ partir de la version 0.3, un canal de MediaSPIP peut devenir privé, bloqué à toute personne non identifiée grâce au plugin "Intranet/extranet".
Le plugin Intranet/extranet, lorsqu’il est activé, permet de bloquer l’accès au canal à tout visiteur non identifié, l’empêchant d’accéder au contenu en le redirigeant systématiquement vers le formulaire d’identification.
Ce système peut être particulièrement utile pour certaines utilisations comme : Atelier de travail avec des enfants dont le contenu ne doit pas (...)
Sur d’autres sites (14556)
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Getting small file size from ffmpeg [duplicate]
20 février 2020, par sukachI am not an ffmpeg expert. I am trying to get some movies converted to a smaller DIVX file for a cheap portable DVD player for a family trip. The movies are for my kids so I’m not too concerned about quality.
The DVD player is a 10.1", 1024x600 screen. It says it supports DIVX/MPEG2 files. It took me a lot of experimentation to get the right ffmpeg settings to even get it to work, but I found another answer that provided a very complex set of parameters that ultimately worked.
I have converted about 20 movies with this setting and every one results in a file size of 1.1GB. I have tried different file sizes and crf settings and it is the same every time.
Here is an example. First, the original file :
General
Complete name : Charlotte's Web.m4v
Format : MPEG-4
Format profile : Base Media / Version 2
Codec ID : mp42 (isom/iso2/avc1/mp41)
File size : 4.17 GiB
Duration : 1 h 36 min
Overall bit rate mode : Variable
Overall bit rate : 6 161 kb/s
Movie name : Charlotte's Web
Performer : Julia Roberts, Steve Buscemi, John Cleese, Oprah Winfrey, Cedric the Entertainer, Reba McEntire, Kathy Bates, Robert Redford, Thomas Haden Church, André Benjamin, Dominic Scott Kay, Sam Shepard, Abraham Benrubi, Dakota Fanning, Kevin Anderson, Essie Davis, Siobhan Fallon, Louis Corbett, Robyn Arthur, Julian O'Donnell, Gary Basaraba, Nate Mooney, Nicholas Bell, Beau Bridges, Teague Rook, Julia Zemiro, Denise Kirby, Robert Plazek, Joseph Lotesto, Michael Roland, Don Bridges, Ian Watkin, Joel McCrary, Brian Stepanek, Fred Tatasciore, Bradley White, Maia Kirkpatrick, Jennessa Rose, Briana Hodge, Dale Azzopardi, Geoff Burgess, Ella Scott Lynch, Greg Marian, Stefano Mazzeo, Elizabeth Saunders
Director : Gary Winick
Actor : Julia Roberts / Steve Buscemi / John Cleese / Oprah Winfrey / Cedric the Entertainer / Reba McEntire / Kathy Bates / Robert Redford / Thomas Haden Church / André Benjamin / Dominic Scott Kay / Sam Shepard / Abraham Benrubi / Dakota Fanning / Kevin Anderson / Essie Davis / Siobhan Fallon / Louis Corbett / Robyn Arthur / Julian O'Donnell / Gary Basaraba / Nate Mooney / Nicholas Bell / Beau Bridges / Teague Rook / Julia Zemiro / Denise Kirby / Robert Plazek / Joseph Lotesto / Michael Roland / Don Bridges / Ian Watkin / Joel McCrary / Brian Stepanek / Fred Tatasciore / Bradley White / Maia Kirkpatrick / Jennessa Rose / Briana Hodge / Dale Azzopardi / Geoff Burgess / Ella Scott Lynch / Greg Marian / Stefano Mazzeo / Elizabeth Saunders
Screenplay by : Karey Kirkpatrick / Susannah Grant / Earl Hamner / Jr. / E.B. White
Producer : Julia Pistor / Jordan Kerner / Paul Neesan / Edgar M. Bronfman / Bernard Williams / Tony Winley
Genre : Comedy
ContentType : Short Film
Description : Wilbur the pig is scared of the end of the season, because he knows that come that time, he will end up on the dinner table. He hatches a plan with Charlotte, a spider that lives in his pen, to ensure that this will never happen.
Recorded date : UTC 2006-12-15 11:00:00
Encoded date : UTC 2017-01-23 02:37:54
Tagged date : UTC 2017-01-24 01:19:52
Writing application : HandBrake 1.0.1 2016122900
Cover : Yes
LongDescription : Wilbur the pig is scared of the end of the season, because he knows that come that time, he will end up on the dinner table. He hatches a plan with Charlotte, a spider that lives in his pen, to ensure that this will never happen.
ContentRating : mpaa|G|100|
Video
ID : 1
Format : AVC
Format/Info : Advanced Video Codec
Format profile : High@L4
Format settings : CABAC / 4 Ref Frames
Format settings, CABAC : Yes
Format settings, ReFrames : 4 frames
Codec ID : avc1
Codec ID/Info : Advanced Video Coding
Duration : 1 h 36 min
Bit rate : 5 691 kb/s
Width : 1 920 pixels
Height : 1 080 pixels
Display aspect ratio : 16:9
Frame rate mode : Variable
Frame rate : 23.976 (24000/1001) FPS
Minimum frame rate : 23.974 FPS
Maximum frame rate : 23.981 FPS
Color space : YUV
Chroma subsampling : 4:2:0
Bit depth : 8 bits
Scan type : Progressive
Bits/(Pixel*Frame) : 0.114
Stream size : 3.86 GiB (92%)
Writing library : x264 core 148 r2708 86b7198
Encoding settings : cabac=1 / ref=3 / deblock=1:-1:-1 / analyse=0x3:0x113 / me=hex / subme=7 / psy=1 / psy_rd=1.00:0.15 / mixed_ref=1 / me_range=16 / chroma_me=1 / trellis=1 / 8x8dct=1 / cqm=0 / deadzone=21,11 / fast_pskip=1 / chroma_qp_offset=-3 / threads=6 / lookahead_threads=1 / sliced_threads=0 / nr=0 / decimate=1 / interlaced=0 / bluray_compat=0 / constrained_intra=0 / bframes=3 / b_pyramid=2 / b_adapt=1 / b_bias=0 / direct=1 / weightb=1 / open_gop=0 / weightp=2 / keyint=240 / keyint_min=24 / scenecut=40 / intra_refresh=0 / rc_lookahead=40 / rc=crf / mbtree=1 / crf=22.0 / qcomp=0.60 / qpmin=0 / qpmax=69 / qpstep=4 / vbv_maxrate=25000 / vbv_bufsize=31250 / crf_max=0.0 / nal_hrd=none / filler=0 / ip_ratio=1.40 / aq=1:1.00
Encoded date : UTC 2017-01-23 02:37:54
Tagged date : UTC 2017-01-23 02:37:54
Color range : Limited
Color primaries : BT.709
Transfer characteristics : BT.709
Matrix coefficients : BT.709
Menus : 4Here is the first encode settings :
ffmpeg -i "$1" -sn -c:a libmp3lame -ar 48000 -ab 128k -ac 2 -c:v mpeg4 -crf 24 -vtag DIVX -vf scale=1024x600:force_original_aspect_ratio=decrease -mbd rd -flags +mv4+aic -trellis 2 -cmp 2 -subcmp 2 -g 30 -vb 1500k "$2"
And the resulting mediainfo :
General
Complete name : Charlotte's Web (2006) - DIVX.avi
Format : AVI
Format/Info : Audio Video Interleave
Format profile : OpenDML
File size : 1.11 GiB
Duration : 1 h 36 min
Overall bit rate : 1 644 kb/s
Movie name : Charlotte's Web
Director : Julia Roberts, Steve Buscemi, John Cleese, Oprah Winfrey, Cedric the Entertainer, Reba McEntire, Kathy Bates, Robert Redford, Thomas Haden Church, André Benjamin, Dominic Scott Kay, Sam Shepard, Abraham Benrubi, Dakota Fanning, Kevin Anderson, Essie Davis, Siobhan Fallon, Louis Corbett, Robyn Arthur, Julian O'Donnell, Gary Basaraba, Nate Mooney, Nicholas Bell, Beau Bridges, Teague Rook, Julia Zemiro, Denise Kirby, Robert Plazek, Joseph Lotesto, Michael Roland, Don Bridges, Ian Watkin, Joel McCrary, Brian Stepanek, Fred Tatasciore, Bradley White, Maia Kirkpatrick, Jennessa Rose, Briana Hodge, Dale Azzopardi, Geoff Burgess, Ella Scott Lynch, Greg Marian, Stefano Mazzeo, Elizabeth Saunders
Genre : Comedy
Recorded date : UTC 2006-12-15 11:00:00
Writing application : Lavf57.56.100
Video
ID : 0
Format : MPEG-4 Visual
Format profile : Simple@L1
Format settings, BVOP : No
Format settings, QPel : No
Format settings, GMC : No warppoints
Format settings, Matrix : Default (H.263)
Codec ID : DIVX
Codec ID/Info : Project Mayo
Codec ID/Hint : DivX 4
Duration : 1 h 36 min
Bit rate : 1 500 kb/s
Width : 1 024 pixels
Height : 576 pixels
Display aspect ratio : 16:9
Frame rate : 23.976 (24000/1001) FPS
Color space : YUV
Chroma subsampling : 4:2:0
Bit depth : 8 bits
Scan type : Progressive
Compression mode : Lossy
Bits/(Pixel*Frame) : 0.106
Stream size : 1.02 GiB (91%)
Writing library : Lavc57.64.100Here was my attempt at a smaller file size (lower crf and smaller scale setting) :
ffmpeg -i "Charlotte's Web.m4v" -sn -c:a libmp3lame -ar 48000 -ab 128k -ac 2 -c:v mpeg4 -crf 30 -vtag DIVX -vf scale=800:480 -mbd rd -flags +mv4+aic -trellis 2 -cmp 2 -subcmp 2 -g 30 -vb 1500k "Charlotte's Web (2006) - DIVX 2.avi"
And the resulting mediainfo :
General
Complete name : Charlotte's Web (2006) - DIVX 2.avi
Format : AVI
Format/Info : Audio Video Interleave
Format profile : OpenDML
File size : 1.11 GiB
Duration : 1 h 36 min
Overall bit rate : 1 643 kb/s
Movie name : Charlotte's Web
Director : Julia Roberts, Steve Buscemi, John Cleese, Oprah Winfrey, Cedric the Entertainer, Reba McEntire, Kathy Bates, Robert Redford, Thomas Haden Church, André Benjamin, Dominic Scott Kay, Sam Shepard, Abraham Benrubi, Dakota Fanning, Kevin Anderson, Essie Davis, Siobhan Fallon, Louis Corbett, Robyn Arthur, Julian O'Donnell, Gary Basaraba, Nate Mooney, Nicholas Bell, Beau Bridges, Teague Rook, Julia Zemiro, Denise Kirby, Robert Plazek, Joseph Lotesto, Michael Roland, Don Bridges, Ian Watkin, Joel McCrary, Brian Stepanek, Fred Tatasciore, Bradley White, Maia Kirkpatrick, Jennessa Rose, Briana Hodge, Dale Azzopardi, Geoff Burgess, Ella Scott Lynch, Greg Marian, Stefano Mazzeo, Elizabeth Saunders
Genre : Comedy
Recorded date : UTC 2006-12-15 11:00:00
Writing application : Lavf57.56.100
Video
ID : 0
Format : MPEG-4 Visual
Format profile : Simple@L1
Format settings, BVOP : No
Format settings, QPel : No
Format settings, GMC : No warppoints
Format settings, Matrix : Default (H.263)
Codec ID : DIVX
Codec ID/Info : Project Mayo
Codec ID/Hint : DivX 4
Duration : 1 h 36 min
Bit rate : 1 499 kb/s
Width : 800 pixels
Height : 480 pixels
Display aspect ratio : 16:9
Frame rate : 23.976 (24000/1001) FPS
Color space : YUV
Chroma subsampling : 4:2:0
Bit depth : 8 bits
Scan type : Progressive
Compression mode : Lossy
Bits/(Pixel*Frame) : 0.163
Stream size : 1.02 GiB (91%)
Writing library : Lavc57.64.100Same file size but lower resolution.
Any ideas on what the best settings to achieve my goal ?
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Maintain PTS on .ts file resize
5 février 2020, par PRManLet’s say I have a .ts file from an existing HLS and I simply want to resize it. For example, to create a second lower-resolution stream that can be switched when bandwidth is poor.
ffmpeg -i video1080_1.ts -vf "scale=1280:720" video720_1.ts
How do I ensure that video720_1.ts starts at the exact same PTS as video1080_1.ts ? I haven’t changed the rate, so it will play fine as long as it starts at the exact same PTS.
I have tried a lot of things (vsync, copyts, etc.) but none of them give me the exact same number.
Also, I tried adding
-copyts -vsync 2 -muxdelay 0 -muxpreload 0
and that got it closer, but still off by 1100 (4422778 vs 4423680). -
does av_read_frame add FF_INPUT_BUFFER_PADDING_SIZE ?
3 juillet 2015, par eladm26I’m using libav to read an MPEG stream.
I’m using the functionav_read_frame()
to read some frames into packets :av_read_frame(pFormatCtx, &packet)
I then use the function
avcodec_decode_video2
to decode the packet into frame.
the documentation of the functionavcodec_decode_video2
contains the following warning :The input buffer must be FF_INPUT_BUFFER_PADDING_SIZE larger than the
actual read bytes because some optimized bitstream readers read 32 or
64 bits at once and could read over the end. The end of the input
buffer buf should be set to 0 to ensure that no overreading happens
for damaged MPEG streams.I wanted to know if the function
av_read_frame
doesn’t already allocate the additional FF_INPUT_BUFFER_PADDING_SIZE ?Thank you.