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  • HTML5 audio and video support

    13 avril 2011, par

    MediaSPIP 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 (...)

  • Support audio et vidéo HTML5

    10 avril 2011

    MediaSPIP 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 (...)

  • De l’upload à la vidéo finale [version standalone]

    31 janvier 2010, par

    Le 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 (4562)

  • Linux Media Player Survey Circa 2001

    2 septembre 2010, par Multimedia Mike — General

    Here’s a document I scavenged from my archives. It was dated September 1, 2001 and I now publish it 9 years later. It serves as sort of a time capsule for the state of media player programs at the time. Looking back on this list, I can’t understand why I couldn’t find MPlayer while I was conducting this survey, especially since MPlayer is the project I eventually started to work for a few months after writing this piece.

    For a little context, I had been studying multimedia concepts and tech for a year and was itching to get my hands dirty with practical multimedia coding. But I wanted to tackle what I perceived as unsolved problems– like playback of proprietary codecs. I didn’t want to have to build a new media playback framework just to start working on my problems. So I surveyed the players available to see which ones I could plug into and use as a testbed for implementing new decoders.

    Regarding Real Player, I wrote : “We’re trying to move away from the proprietary, closed-source “solutions”. Heh. Was I really an insufferable open source idealist back in the day ?

    Anyway, here’s the text with some Where are they now ? commentary [in brackets] :

    Towards an All-Inclusive Media Playing Solution for Linux

    I don’t feel that the media playing solutions for Linux set their sights high enough, even though they do tend to be quite ambitious.

    I want to create a media player for Linux that can open a file, figure out what type of file it is (AVI, MOV, etc.), determine the compression algorithms used to encode the audio and video chunks inside (MPEG, Cinepak, Sorenson, etc.) and replay the file using the best audio, video, and CPU facilities available on the computer.

    Video and audio playback is a solved problem on Linux ; I don’t wish to solve that problem again. The problem that isn’t solved is reliance on proprietary multimedia solutions through some kind of WINE-like layer in order to decode compressed multimedia files.

    Survey of Linux solutions for decoding proprietary multimedia
    updated 2001-09-01

    AVI Player for XMMS
    This is based on Avifile. All the same advantages and limitations apply.
    [Top Google hit is a Freshmeat page that doesn’t indicate activity since 2001-2002.]

    Avifile
    This player does a great job at taking apart AVI and ASF files and then feeding the compressed chunks of multimedia data through to the binary Win32 decoders.

    The program is written in C++ and I’m not very good at interpreting that kind of code. But I’m learning all over again. Examining the object hierarchy, it appears that the designers had the foresight to include native support for decoders that are compiled into the program from source code. However, closer examination reveals that there is support for ONE source decoder and that’s the “decoder” for uncompressed data. Still, I tried to manipulate this routine to accept and decode data from other codecs but no dice. It’s really confounding. The program always crashes when I feed non-uncompressed data through the source decoder.
    [Lives at http://avifile.sourceforge.net/ ; not updated since 2006.]

    Real Player
    There’s not much to do with this since it is closed source and proprietary. Even though there is a plugin architecture, that’s not satisfactory. We’re trying to move away from the proprietary, closed-source “solutions”.
    [Still kickin’ with version 11.]

    XAnim
    This is a well-established Unix media player. To his credit, the author does as well as he can with the resources he has. In other words, he supports the non-proprietary video codecs well, and even has support for some proprietary video codecs through binary-only decoders.

    The source code is extremely difficult to work with as the author chose to use the X coding format which I’ve never seen used anywhere else except for X header files. The infrastructure for extending the program and supporting other codecs and file formats is there, I suppose, but I would have to wrap my head around the coding style. Maybe I can learn to work past that. The other thing that bothers me about this program is the decoding approach : It seems that each video decoder includes routines to decompress the multimedia data into every conceivable RGB and YUV output format. This seems backwards to me ; it seems better to have one decoder function that decodes the data into its native format it was compressed from (e.g., YV12 for MPEG data) and then pass that data to another layer of the program that’s in charge of presenting the data and possibly converting it if necessary. This layer would encompass highly-optimized software conversion routines including special CPU-specific instructions (e.g., MMX and SSE) and eliminate the need to place those routines in lots of other routines. But I’m getting ahead of myself.
    [This one was pretty much dead before I made this survey, the most recent update being in 1999. Still, we owe it much respect as the granddaddy of Unix multimedia playback programs.]

    Xine
    This seems like a promising program. It was originally designed to play MPEGs from DVDs. It can also play MPEG files on a hard drive and utilizes the Xv extensions for hardware YUV playback. It’s also supposed to play AVI files using the same technique as Avifile but I have never, ever gotten it to work. If an AVI file has both video and sound, the binary video decoder can’t decode any frames. If the AVI file has video and no sound, the program gets confused and crashes, as far as I can tell.

    Still, it’s promising, and I’ve been trying to work around these crashes. It doesn’t yet have the type of modularization I’d like to see. Right now, it tailored to suit MPEG playback and AVI playback is an afterthought. Still, it appears to have a generalized interface for dropping in new file demultiplexers.

    I tried to extend the program for supporting source decoders by rewriting w32codec.c from scratch. I’m not having a smooth time of it so far. I’m able to perform some manipulations on the output window. However, I can’t get the program to deal with an RGB image format. It has trouble allocating an RGB surface with XvShmCreateImage(). This isn’t suprising, per my limited knowledge of X which is that Xv applies to YUV images, but it could also apply to RGB images as well. Anyway, the program should be able to fall back on regular RGB pixmaps if that Xv call fails.

    Right now, this program is looking the most promising. It will take some work to extend the underlying infrastructure, but it seems doable since I know C quite well and can understand the flow of this program, as opposed to Avifile and its C++. The C code also compiles about 10 times faster.
    [My home project for many years after a brief flirtation with MPlayer. It is still alive ; its latest release was just a month ago.]

    XMovie
    This library is a Quicktime movie player. I haven’t looked at it too extensively yet, but I do remember looking at it at one point and reading the documentation that said it doesn’t support key frames. Still, I should examine it again since they released a new version recently.
    [Heroine Virtual still puts out some software but XMovie has not been updated since 2005.]

    XMPS
    This program compiles for me, but doesn’t do much else. It can play an MP3 file. I have been able to get MPEG movies to play through it, but it refuses to show the full video frame, constricting it to a small window (obviously a bug).
    [This project is hosted on SourceForge and is listed with a registration date of 2003, well after this survey was made. So the project obviously lived elsewhere in 2001. Meanwhile, it doesn’t look like any files ever made it to SF for hosting.]

    XTheater
    I can’t even get this program to compile. It’s supposed to be an MPEG player based on SMPEG. As such, it probably doesn’t hold much promise for being easily extended into a general media player.
    [Last updated in 2002.]

    GMerlin
    I can’t get this to compile yet. I have a bug report in to the dev group.
    [Updated consistently in the last 9 years. Last update was in February of this year. I can’t find any record of my bug report, though.]

  • How to Simply Remove Duplicate Frames from a Video using ffmpeg

    29 janvier 2017, par Skeeve

    First of all, I’d preface this by saying I’m NO EXPERT with video manipulation,
    although I’ve been fiddling with ffmpeg for years (in a fairly limited way). Hence, I’m not too flash with all the language folk often use... and how it affects what I’m trying to do in my manipulations... but I’ll have a go with this anyway...

    I’ve checked a few links here, for example :
    ffmpeg - remove sequentially duplicate frames

    ...but the content didn’t really help me.

    I have some hundreds of video clips that have been created under both Windows and Linux using both ffmpeg and other similar applications. However, they have some problems with times in the video where the display is ’motionless’.

    As an example, let’s say we have some web site that streams a live video into, say, a Flash video player/plugin in a web browser. In this case, we’re talking about a traffic camera video stream, for example.

    There’s an instance of ffmpeg running that is capturing a region of the (Windows) desktop into a video file, viz :-

    ffmpeg -hide_banner -y -f dshow ^
    
      -i video="screen-capture-recorder" ^
    
      -vf "setpts=1.00*PTS,crop=448:336:620:360" ^
    
      -an -r 25 -vcodec libx264 -crf 0 -qp 0 ^
    
      -preset ultrafast SAMPLE.flv

    Let’s say the actual ’display’ that is being captured looks like this :-

    123456789 XXXXX 1234567 XXXXXXXXXXX 123456789 XXXXXXX
    
^---a---^ ^-P-^ ^--b--^ ^----Q----^ ^---c---^ ^--R--^

    ...where each character position represents a (sequence of) frame(s). Owing to a poor internet connection, a "single frame" can be displayed for an extended period (the ’X’ characters being an (almost) exact copy of the immediately previous frame). So this means we have segments of the captured video where the image doesn’t change at all (to the naked eye, anyway).

    How can we deal with the duplicate frames ?... and how does our approach change if the ’duplicates’ are NOT the same to ffmpeg but LOOK more-or-less the same to the viewer ?

    If we simply remove the duplicate frames, the ’pacing’ of the video is lost, and what used to take, maybe, 5 seconds to display, now takes a fraction of a second, giving a very jerky, unnatural motion, although there are no duplicate images in the video. This seems to be achievable using ffmpeg with an ’mp_decimate’ option, viz :-

         ffmpeg -i SAMPLE.flv ^                      ... (i)
    
        -r 25 ^
    
        -vf mpdecimate,setpts=N/FRAME_RATE/TB DEC_SAMPLE.mp4

    That reference I quoted uses a command that shows which frames ’mp_decimate’ will remove when it considers them to be ’the same’, viz :-

         ffmpeg -i SAMPLE.flv ^                      ... (ii)
    
        -vf mpdecimate ^
    
        -loglevel debug -f null -

    ...but knowing that (complicated formatted) information, how can we re-organize the video without executing multiple runs of ffmpeg to extract ’slices’ of video for re-combining later ?

    In that case, I’m guessing we’d have to run something like :-

    • user specifies a ’threshold duration’ for the duplicates
      (maybe run for 1 sec only)
    • determine & save main video information (fps, etc - assuming
      constant frame rate)
    • map the (frame/time where duplicates start)->no. of
      frames/duration of duplicates
    • if the duration of duplicates is less than the user threshold,
      don’t consider this period as a ’series of duplicate frames’
      and move on
    • extract the ’non-duplicate’ video segments (a, b & c in the
      diagram above)
    • create ’new video’ (empty) with original video’s specs
    • for each video segment
      extract the last frame of the segment
      create a short video clip with repeated frames of the frame
      just extracted (duration = user spec. = 1 sec)
      append (current video segment+short clip) to ’new video’
      and repeat

    ...but in my case, a lot of the captured videos might be 30 minutes long and have hundreds of 10 sec long pauses, so the ’rebuilding’ of the videos will take a long time using this method.

    This is why I’m hoping there’s some "reliable" and "more intelligent" way to use
    ffmepg (with/without the ’mp_decimate’ filter) to do the ’decimate’ function in only a couple of passes or so... Maybe there’s a way that the required segments could even be specified (in a text file, for example) and as ffmpeg runs it will
    stop/restart it’s transcoding at specified times/frame numbers ?

    Short of this, is there another application (for use on Windows or Linux) that could do what I’m looking for, without having to manually set start/stop points,
    extracting/combining video segments manually...?

    I’ve been trying to do all this with ffmpeg N-79824-gcaee88d under Win7-SP1 and (a different version I don’t currently remember) under Puppy Linux Slacko 5.6.4.

    Thanks a heap for any clues.

  • Converting mp4 audio & video for HTML5

    10 janvier 2020, par Crayzzit

    So I have two files. frag_bunny.mp4 and raw.mp4 (you can download them in a tar on my Google drive). The frag_bunny.mp4 works perfectly when I use it with the MediaSource’s JavaScript API. But it’s not the case with raw.mp4, why is that ?

    Here’s the mediainfo of frag_bunny.mp4 :

    General
    
Complete name                            : frag_bunny.mp4
    
Format                                   : MPEG-4
    
Format profile                           : Base Media / Version 2
    
Codec ID                                 : mp42 (mp42/avc1/iso5)
    
File size                                : 5.27 MiB
    
Duration                                 : 1 min 0 s
    
Overall bit rate                         : 734 kb/s
    

    
Video
    
ID                                       : 2
    
Format                                   : AVC
    
Format/Info                              : Advanced Video Codec
    
Format profile                           : Baseline@L3
    
Format settings                          : 2 Ref Frames
    
Format settings, CABAC                   : No
    
Format settings, ReFrames                : 2 frames
    
Format settings, GOP                     : M=1, N=64
    
Codec ID                                 : avc1
    
Codec ID/Info                            : Advanced Video Coding
    
Duration                                 : 1 min 0 s
    
Bit rate                                 : 613 kb/s
    
Width                                    : 640 pixels
    
Height                                   : 360 pixels
    
Display aspect ratio                     : 16:9
    
Frame rate mode                          : Variable
    
Frame rate                               : 23.976 (23976/1000) FPS
    
Minimum frame rate                       : 7.317 FPS
    
Maximum frame rate                       : 24.000 FPS
    
Color space                              : YUV
    
Chroma subsampling                       : 4:2:0
    
Bit depth                                : 8 bits
    
Scan type                                : Progressive
    
Bits/(Pixel*Frame)                       : 0.111
    
Stream size                              : 4.39 MiB (83%)
    
Language                                 : English
    
Color range                              : Limited
    
Color primaries                          : BT.601 NTSC
    
Transfer characteristics                 : BT.709
    
Matrix coefficients                      : BT.601
    

    
Audio
    
ID                                       : 1
    
Format                                   : AAC
    
Format/Info                              : Advanced Audio Codec
    
Format profile                           : LC
    
Codec ID                                 : mp4a-40-2
    
Duration                                 : 1 min 0 s
    
Bit rate mode                            : Constant
    
Bit rate                                 : 64.0 kb/s
    
Channel(s)                               : 2 channels
    
Channel positions                        : Front: L R
    
Sampling rate                            : 22.05 kHz
    
Frame rate                               : 21.533 FPS (1024 SPF)
    
Compression mode                         : Lossy
    
Stream size                              : 478 KiB (9%)
    
Language                                 : English
    

    
Other #1
    
ID                                       : 3
    
Type                                     : Hint
    
Format                                   : RTP
    
Codec ID                                 : rtp
    
Duration                                 : 1 min 0 s
    
Language                                 : English
    

    
Other #2
    
ID                                       : 4
    
Type                                     : Hint
    
Format                                   : RTP
    
Codec ID                                 : rtp
    
Duration                                 : 1 min 0 s
    
Language                                 : English

    And same for raw.mp4 :

    General
    
Complete name                            : raw.mp4
    
Format                                   : MPEG-4
    
Format profile                           : Base Media / Version 2
    
Codec ID                                 : mp42 (isom/iso2/avc1/mp41)
    
File size                                : 16.9 MiB
    
Duration                                 : 3 min 32 s
    
Overall bit rate                         : 668 kb/s
    
Writing application                      : Lavf57.83.100
    

    
Video
    
ID                                       : 1
    
Format                                   : AVC
    
Format/Info                              : Advanced Video Codec
    
Format profile                           : High@L3
    
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                                 : 3 min 32 s
    
Bit rate                                 : 532 kb/s
    
Width                                    : 640 pixels
    
Height                                   : 360 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)                       : 0.092
    
Stream size                              : 13.4 MiB (80%)
    
Writing library                          : x264 core 152 r2854 e9a5903
    
Encoding settings                        : cabac=1 / ref=3 / deblock=1:0:0 / analyse=0x3:0x113 / me=hex / subme=7 / psy=1 / psy_rd=1.00:0.00 / mixed_ref=1 / me_range=16 / chroma_me=1 / trellis=1 / 8x8dct=1 / cqm=0 / deadzone=21,11 / fast_pskip=1 / chroma_qp_offset=-2 / 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=250 / keyint_min=25 / scenecut=40 / intra_refresh=0 / rc_lookahead=40 / rc=crf / mbtree=1 / crf=23.0 / qcomp=0.60 / qpmin=0 / qpmax=69 / qpstep=4 / ip_ratio=1.40 / aq=1:1.00
    

    
Audio
    
ID                                       : 2
    
Format                                   : AAC
    
Format/Info                              : Advanced Audio Codec
    
Format profile                           : LC
    
Codec ID                                 : mp4a-40-2
    
Duration                                 : 3 min 32 s
    
Bit rate mode                            : Constant
    
Bit rate                                 : 132 kb/s
    
Channel(s)                               : 2 channels
    
Channel positions                        : Front: L R
    
Sampling rate                            : 44.1 kHz
    
Frame rate                               : 43.066 FPS (1024 SPF)
    
Compression mode                         : Lossy
    
Stream size                              : 3.30 MiB (20%)
    
Default                                  : Yes
    
Alternate group                          : 1

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