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Autres articles (105)

  • Ajouter des informations spécifiques aux utilisateurs et autres modifications de comportement liées aux auteurs

    12 avril 2011, par

    La manière la plus simple d’ajouter des informations aux auteurs est d’installer le plugin Inscription3. Il permet également de modifier certains comportements liés aux utilisateurs (référez-vous à sa documentation pour plus d’informations).
    Il est également possible d’ajouter des champs aux auteurs en installant les plugins champs extras 2 et Interface pour champs extras.

  • Les autorisations surchargées par les plugins

    27 avril 2010, par

    Mediaspip core
    autoriser_auteur_modifier() afin que les visiteurs soient capables de modifier leurs informations sur la page d’auteurs

  • Other interesting software

    13 avril 2011, par

    We don’t claim to be the only ones doing what we do ... and especially not to assert claims to be the best either ... What we do, we just try to do it well and getting better ...
    The following list represents softwares that tend to be more or less as MediaSPIP or that MediaSPIP tries more or less to do the same, whatever ...
    We don’t know them, we didn’t try them, but you can take a peek.
    Videopress
    Website : http://videopress.com/
    License : GNU/GPL v2
    Source code : (...)

Sur d’autres sites (10406)

  • How to encode with ffmpeg if number of images smaller than GOP size

    10 avril 2013, par theateist

    The code bellow creates mp4 video file from jpeg images. When number of images is greater than GOP size the encoding success and after 10th image gotPacket that returned by avcodec_encode_video2 is > 0.

    BUT when number of images is smaller than GOP size gotPacket is always = 0 and therefore no images written to the file.

    My guess is that avcodec_encode_video2 allocates buffer with length equals to GOP size and until it won't be full gotPacket will be 0.

    My question is how to force avcodec_encode_video2 to encode even if it's buffer is not full ?

    ...
    _outStream->codec.gop_size = 10;
    _outStream->codec.keyint_min = 10;
    ...

    AVFrame* frame = getFrame();


    AVPacket packet;
    av_init_packet(&packet);
    packet.data = NULL;
    packet.size = 0;

    int gotPacket = 0;
    if (avcodec_encode_video2(_outStream->codec, &packet, frame, &gotPacket) < 0)
       throw std::runtime_error("failed to encode frame");

    if (gotPacket)
    {
       ...
       if (av_write_frame(_outContainer.get(), &packet) < 0)
           throw std::runtime_error("failed to write frame");      
       av_free_packet(&packet);
    }
  • Injecting Metadata into an .mp4 file

    21 août 2019, par TrueCP5

    I’m working on a library that injects metadata into a .mp4 file to allow the video to be displayed correctly as a 360 video. The input file is a standard .mp4 file in the equirectangular format. I know what metadata needs to be injected I just do not know how to inject it.

    I spent some time looking around for libraries that can do this but could only find ones for extracting metadata not injecting/embedding/writing it. The alternative I found was to use Spatial Media as a command line application to inject the metadata more easily. The problem is I know zero python whatsoever so I’m leaning towards a library/nuget package/ffmpeg script.

    Does a good nuget package/library exist that can do this or should I go for the alternative option ?

    Edit 1

    I have tried just pasting in the metadata into the correct place in the file, just in case it might work, but it didn’t.

    Edit 2

    This is the metadata injected by Google’s Spatial Media Tool which is what I am trying to achieve :

    <?xml version="1.0"?>truetrueSpherical Metadata Toolequirectangular`

    Edit 3

    I’ve also tried to do it with ffmpeg like so : ffmpeg -i input.mp4 -movflags use_metadata_tags -metadata Spherical=true -metadata Stitched=true -metadata ProjectionType=equirectangular -metadata StitchingSoftware=StreetviewJourney -codec copy output.mp4

    I think the issue with the ffmpeg method is that it does not contain the rdf:SphericalVideo part which allows the spherical video tags to be used.

    Edit 4

    When I extract the metadata using ffmpeg it contains the spherical tag in the logs but not when I output it to a ffmetadata file. This was the command I used : ffmpeg -i injected.mp4 -map_metadata -1 -f ffmetadata data.txt

    This is the output of the log :

    fps, 60 tbr, 15360 tbn, 120 tbc (default)
       Metadata:
         handler_name    : VideoHandler
       Side data:
         spherical: equirectangular (0.000000/0.000000/0.000000)

    Edit 5

    I also tried to get the metadata using this command : ffprobe -v error -select_streams v:0 -show_streams -of default=noprint_wrappers=1 injected.mp4

    This was the logs it outputted :

    TAG:handler_name=VideoHandler
    side_data_type=Spherical Mapping
    projection=equirectangular
    yaw=0
    pitch=0
    roll=0

    I then tried to use this command but it didn’t work : ffmpeg -i chapmanspeak.mp4 -movflags use_metadata_tags -metadata side_metadata_type="Spherical Mapping" -metadata projection=equirectangular -metadata yaw=0 -metadata pitch=0 -metadata roll=0 -codec copy output.mp4

    Edit 6

    I tried @VC.One’s method but I must be doing something wrong because the output file is unplayable. Here is my code :

           public static void Metadata(string inputFile, string outputFile)
           {
               byte[] metadata = HexStringToByteArray("3C 3F 78 6D 6C 20 76 65 72 73 69 6F 6E 3D 22 31 2E 30 22 3F 3E 3C 72 64 66 3A 53 70 68 65 72 69 63 61 6C 56 69 64 65 6F 0A 78 6D 6C 6E 73 3A 72 64 66 3D 22 68 74 74 70 3A 2F 2F 77 77 77 2E 77 33 2E 6F 72 67 2F 31 39 39 39 2F 30 32 2F 32 32 2D 72 64 66 2D 73 79 6E 74 61 78 2D 6E 73 23 22 0A 78 6D 6C 6E 73 3A 47 53 70 68 65 72 69 63 61 6C 3D 22 68 74 74 70 3A 2F 2F 6E 73 2E 67 6F 6F 67 6C 65 2E 63 6F 6D 2F 76 69 64 65 6F 73 2F 31 2E 30 2F 73 70 68 65 72 69 63 61 6C 2F 22 3E 3C 47 53 70 68 65 72 69 63 61 6C 3A 53 70 68 65 72 69 63 61 6C 3E 74 72 75 65 3C 2F 47 53 70 68 65 72 69 63 61 6C 3A 53 70 68 65 72 69 63 61 6C 3E 3C 47 53 70 68 65 72 69 63 61 6C 3A 53 74 69 74 63 68 65 64 3E 74 72 75 65 3C 2F 47 53 70 68 65 72 69 63 61 6C 3A 53 74 69 74 63 68 65 64 3E 3C 47 53 70 68 65 72 69 63 61 6C 3A 53 74 69 74 63 68 69 6E 67 53 6F 66 74 77 61 72 65 3E 53 70 68 65 72 69 63 61 6C 20 4D 65 74 61 64 61 74 61 20 54 6F 6F 6C 3C 2F 47 53 70 68 65 72 69 63 61 6C 3A 53 74 69 74 63 68 69 6E 67 53 6F 66 74 77 61 72 65 3E 3C 47 53 70 68 65 72 69 63 61 6C 3A 50 72 6F 6A 65 63 74 69 6F 6E 54 79 70 65 3E 65 71 75 69 72 65 63 74 61 6E 67 75 6C 61 72 3C 2F 47 53 70 68 65 72 69 63 61 6C 3A 50 72 6F 6A 65 63 74 69 6F 6E 54 79 70 65 3E 3C 2F 72 64 66 3A 53 70 68 65 72 69 63 61 6C 56 69 64 65 6F 3E");
               byte[] stco = HexStringToByteArray("73 74 63 6F");
               byte[] moov = HexStringToByteArray("6D 6F 6F 76");
               byte[] trak = HexStringToByteArray("74 72 61 6B");

               byte[] file = File.ReadAllBytes(inputFile);

               //find trak
               int trakPosition = 0;
               for (int a = 0; a < file.Length - trak.Length; a++)
               {
                   for (int b = 0; b < trak.Length; b++)
                   {
                       if (file[a + b] != trak[b])
                           break;
                       if (b == trak.Length - 1)
                           trakPosition = a;
                   }
               }
               if (trakPosition == 0)
                   throw new FileLoadException();

               //add metadata
               int trakLength = BitConverter.ToInt32(new ArraySegment<byte>(file, trakPosition - 4, 4).Reverse().ToArray(), 0);
               var fileList = file.ToList();
               fileList.InsertRange(trakPosition - 4 + trakLength, metadata);
               file = fileList.ToArray();

               ////change length - tried this as well
               //byte[] trakBytes = BitConverter.GetBytes(trakLength + metadata.Length).Reverse().ToArray();
               //for (int i = 0; i &lt; 4; i++)
               //    file[trakPosition - 4 + i] = trakBytes[i];

               //find moov
               int moovPosition = 0;
               for (int a = 0; a &lt; file.Length - moov.Length; a++)
               {
                   for (int b = 0; b &lt; moov.Length; b++)
                   {
                       if (file[a + b] != moov[b])
                           break;
                       if (b == moov.Length - 1)
                           moovPosition = a;
                   }
               }
               if (moovPosition == 0)
                   throw new FileLoadException();

               //change length
               int moovLength = BitConverter.ToInt32(new ArraySegment<byte>(file, moovPosition - 4, 4).Reverse().ToArray(), 0);
               byte[] moovBytes = BitConverter.GetBytes(moovLength + metadata.Length).Reverse().ToArray();
               for (int i = 0; i &lt; 4; i++)
                   file[moovPosition - 4 + i] = moovBytes[i];

               //find stco
               int stcoPosition = 0;
               for (int a = 0; a &lt; file.Length - stco.Length; a++)
               {
                   for (int b = 0; b &lt; stco.Length; b++)
                   {
                       if (file[a + b] != stco[b])
                           break;
                       if (b == stco.Length - 1)
                           stcoPosition = a;
                   }
               }
               if (stcoPosition == 0)
                   throw new FileLoadException();

               //modify entries
               int stcoEntries = BitConverter.ToInt32(new ArraySegment<byte>(file, stcoPosition + 8, 4).Reverse().ToArray(), 0);
               for (int a = stcoPosition + 12; a &lt; stcoPosition + 12 + stcoEntries * 4; a += 4)
               {
                   int entryLength = BitConverter.ToInt32(new ArraySegment<byte>(file, a, 4).Reverse().ToArray(), 0);
                   byte[] newEntry = BitConverter.GetBytes(entryLength + metadata.Length).Reverse().ToArray();
                   for (int b = 0; b &lt; 4; b++)
                       file[a + b] = newEntry[b];
               }

               File.WriteAllBytes(outputFile, file);
           }

           private static byte[] HexStringToByteArray(string hex)
           {
               hex = hex.Replace(" ", "");
               return Enumerable.Range(0, hex.Length)
                                .Where(x => x % 2 == 0)
                                .Select(x => Convert.ToByte(hex.Substring(x, 2), 16))
                                .ToArray();
           }
    </byte></byte></byte></byte>

    The bytes are reversed because .mp4s seem to be Little Endian. I tried to also update the length of trak but that didn’t work either.

  • Play video using mse (media source extension) in google chrome

    23 août 2019, par liyuqihxc

    I’m working on a project that convert rtsp stream (ffmpeg) and play it on the web page (signalr + mse).

    So far it works pretty much as I expected on the latest version of edge and firefox, but not chrome.

    here’s the code

    public class WebmMediaStreamContext
    {
       private Process _ffProcess;
       private readonly string _cmd;
       private byte[] _initSegment;
       private Task _readMediaStreamTask;
       private CancellationTokenSource _cancellationTokenSource;

       private const string _CmdTemplate = "-i {0} -c:v libvpx -tile-columns 4 -frame-parallel 1 -keyint_min 90 -g 90 -f webm -dash 1 pipe:";

       public static readonly byte[] ClusterStart = { 0x1F, 0x43, 0xB6, 0x75, 0x01, 0x00, 0x00, 0x00 };

       public event EventHandler<clusterreadyeventargs> ClusterReadyEvent;

       public WebmMediaStreamContext(string rtspFeed)
       {
           _cmd = string.Format(_CmdTemplate, rtspFeed);
       }

       public async Task StartConverting()
       {
           if (_ffProcess != null)
               throw new InvalidOperationException();

           _ffProcess = new Process();
           _ffProcess.StartInfo = new ProcessStartInfo
           {
               FileName = "ffmpeg/ffmpeg.exe",
               Arguments = _cmd,
               UseShellExecute = false,
               CreateNoWindow = true,
               RedirectStandardOutput = true
           };
           _ffProcess.Start();

           _initSegment = await ParseInitSegmentAndStartReadMediaStream();
       }

       public byte[] GetInitSegment()
       {
           return _initSegment;
       }

       // Find the first cluster, and everything before it is the InitSegment
       private async Task ParseInitSegmentAndStartReadMediaStream()
       {
           Memory<byte> buffer = new byte[10 * 1024];
           int length = 0;
           while (length != buffer.Length)
           {
               length += await _ffProcess.StandardOutput.BaseStream.ReadAsync(buffer.Slice(length));
               int cluster = buffer.Span.IndexOf(ClusterStart);
               if (cluster >= 0)
               {
                   _cancellationTokenSource = new CancellationTokenSource();
                   _readMediaStreamTask = new Task(() => ReadMediaStreamProc(buffer.Slice(cluster, length - cluster).ToArray(), _cancellationTokenSource.Token), _cancellationTokenSource.Token, TaskCreationOptions.LongRunning);
                   _readMediaStreamTask.Start();
                   return buffer.Slice(0, cluster).ToArray();
               }
           }

           throw new InvalidOperationException();
       }

       private void ReadMoreBytes(Span<byte> buffer)
       {
           int size = buffer.Length;
           while (size > 0)
           {
               int len = _ffProcess.StandardOutput.BaseStream.Read(buffer.Slice(buffer.Length - size));
               size -= len;
           }
       }

       // Parse every single cluster and fire ClusterReadyEvent
       private void ReadMediaStreamProc(byte[] bytesRead, CancellationToken cancel)
       {
           Span<byte> buffer = new byte[5 * 1024 * 1024];
           bytesRead.CopyTo(buffer);
           int bufferEmptyIndex = bytesRead.Length;

           do
           {
               if (bufferEmptyIndex &lt; ClusterStart.Length + 4)
               {
                   ReadMoreBytes(buffer.Slice(bufferEmptyIndex, 1024));
                   bufferEmptyIndex += 1024;
               }

               int clusterDataSize = BitConverter.ToInt32(
                   buffer.Slice(ClusterStart.Length, 4)
                   .ToArray()
                   .Reverse()
                   .ToArray()
               );
               int clusterSize = ClusterStart.Length + 4 + clusterDataSize;
               if (clusterSize > buffer.Length)
               {
                   byte[] newBuffer = new byte[clusterSize];
                   buffer.Slice(0, bufferEmptyIndex).CopyTo(newBuffer);
                   buffer = newBuffer;
               }

               if (bufferEmptyIndex &lt; clusterSize)
               {
                   ReadMoreBytes(buffer.Slice(bufferEmptyIndex, clusterSize - bufferEmptyIndex));
                   bufferEmptyIndex = clusterSize;
               }

               ClusterReadyEvent?.Invoke(this, new ClusterReadyEventArgs(buffer.Slice(0, bufferEmptyIndex).ToArray()));

               bufferEmptyIndex = 0;
           } while (!cancel.IsCancellationRequested);
       }
    }
    </byte></byte></byte></clusterreadyeventargs>

    I use ffmpeg to convert the rtsp stream to vp8 WEBM byte stream and parse it to "Init Segment" (ebml head、info、tracks...) and "Media Segment" (cluster), then send it to browser via signalR

    $(function () {

       var mediaSource = new MediaSource();
       var mimeCodec = 'video/webm; codecs="vp8"';

       var video = document.getElementById('video');

       mediaSource.addEventListener('sourceopen', callback, false);
       function callback(e) {
           var sourceBuffer = mediaSource.addSourceBuffer(mimeCodec);
           var queue = [];

           sourceBuffer.addEventListener('updateend', function () {
               if (queue.length === 0) {
                   return;
               }

               var base64 = queue[0];
               if (base64.length === 0) {
                   mediaSource.endOfStream();
                   queue.shift();
                   return;
               } else {
                   var buffer = new Uint8Array(atob(base64).split("").map(function (c) {
                       return c.charCodeAt(0);
                   }));
                   sourceBuffer.appendBuffer(buffer);
                   queue.shift();
               }
           }, false);

           var connection = new signalR.HubConnectionBuilder()
               .withUrl("/signalr-video")
               .configureLogging(signalR.LogLevel.Information)
               .build();
           connection.start().then(function () {
               connection.stream("InitVideoReceive")
                   .subscribe({
                       next: function(item) {
                           if (queue.length === 0 &amp;&amp; !!!sourceBuffer.updating) {
                               var buffer = new Uint8Array(atob(item).split("").map(function (c) {
                                   return c.charCodeAt(0);
                               }));
                               sourceBuffer.appendBuffer(buffer);
                               console.log(blockindex++ + " : " + buffer.byteLength);
                           } else {
                               queue.push(item);
                           }
                       },
                       complete: function () {
                           queue.push('');
                       },
                       error: function (err) {
                           console.error(err);
                       }
                   });
           });
       }
       video.src = window.URL.createObjectURL(mediaSource);
    })

    chrome just play the video for 3 5 seconds and then stop for buffering, even though there are plenty of cluster transfered and inserted into SourceBuffer.

    here’s the information in chrome ://media-internals/

    Player Properties :

    render_id: 217
    player_id: 1
    origin_url: http://localhost:52531/
    frame_url: http://localhost:52531/
    frame_title: Home Page
    url: blob:http://localhost:52531/dcb25d89-9830-40a5-ba88-33c13b5c03eb
    info: Selected FFmpegVideoDecoder for video decoding, config: codec: vp8 format: 1 profile: vp8 coded size: [1280,720] visible rect: [0,0,1280,720] natural size: [1280,720] has extra data? false encryption scheme: Unencrypted rotation: 0°
    pipeline_state: kSuspended
    found_video_stream: true
    video_codec_name: vp8
    video_dds: false
    video_decoder: FFmpegVideoDecoder
    duration: unknown
    height: 720
    width: 1280
    video_buffering_state: BUFFERING_HAVE_NOTHING
    for_suspended_start: false
    pipeline_buffering_state: BUFFERING_HAVE_NOTHING
    event: PAUSE

    Log

    Timestamp       Property            Value
    00:00:00 00     origin_url          http://localhost:52531/
    00:00:00 00     frame_url           http://localhost:52531/
    00:00:00 00     frame_title         Home Page
    00:00:00 00     url                 blob:http://localhost:52531/dcb25d89-9830-40a5-ba88-33c13b5c03eb
    00:00:00 00     info                ChunkDemuxer: buffering by DTS
    00:00:00 35     pipeline_state      kStarting
    00:00:15 213    found_video_stream  true
    00:00:15 213    video_codec_name    vp8
    00:00:15 216    video_dds           false
    00:00:15 216    video_decoder       FFmpegVideoDecoder
    00:00:15 216    info                Selected FFmpegVideoDecoder for video decoding, config: codec: vp8 format: 1 profile: vp8 coded size: [1280,720] visible rect: [0,0,1280,720] natural size: [1280,720] has extra data? false encryption scheme: Unencrypted rotation: 0°
    00:00:15 216    pipeline_state      kPlaying
    00:00:15 213    duration            unknown
    00:00:16 661    height              720
    00:00:16 661    width               1280
    00:00:16 665    video_buffering_state       BUFFERING_HAVE_ENOUGH
    00:00:16 665    for_suspended_start         false
    00:00:16 665    pipeline_buffering_state    BUFFERING_HAVE_ENOUGH
    00:00:16 667    pipeline_state      kSuspending
    00:00:16 670    pipeline_state      kSuspended
    00:00:52 759    info                Effective playback rate changed from 0 to 1
    00:00:52 759    event               PLAY
    00:00:52 759    pipeline_state      kResuming
    00:00:52 760    video_dds           false
    00:00:52 760    video_decoder       FFmpegVideoDecoder
    00:00:52 760    info                Selected FFmpegVideoDecoder for video decoding, config: codec: vp8 format: 1 profile: vp8 coded size: [1280,720] visible rect: [0,0,1280,720] natural size: [1280,720] has extra data? false encryption scheme: Unencrypted rotation: 0°
    00:00:52 760    pipeline_state      kPlaying
    00:00:52 793    height              720
    00:00:52 793    width               1280
    00:00:52 798    video_buffering_state       BUFFERING_HAVE_ENOUGH
    00:00:52 798    for_suspended_start         false
    00:00:52 798    pipeline_buffering_state    BUFFERING_HAVE_ENOUGH
    00:00:56 278    video_buffering_state       BUFFERING_HAVE_NOTHING
    00:00:56 295    for_suspended_start         false
    00:00:56 295    pipeline_buffering_state    BUFFERING_HAVE_NOTHING
    00:01:20 717    event               PAUSE
    00:01:33 538    event               PLAY
    00:01:35 94     event               PAUSE
    00:01:55 561    pipeline_state      kSuspending
    00:01:55 563    pipeline_state      kSuspended

    Can someone tell me what’s wrong with my code, or dose chrome require some magic configuration to work ?

    Thanks 

    Please excuse my english :)