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  • Keeping control of your media in your hands

    13 April 2011, by

    The vocabulary used on this site and around MediaSPIP in general, aims to avoid reference to Web 2.0 and the companies that profit from media-sharing.
    While using MediaSPIP, you are invited to avoid using words like "Brand", "Cloud" and "Market".
    MediaSPIP is designed to facilitate the sharing of creative media online, while allowing authors to retain complete control of their work.
    MediaSPIP aims to be accessible to as many people as possible and development is based on expanding the (...)

  • Les images

    15 May 2013

  • Mediabox : ouvrir les images dans l’espace maximal pour l’utilisateur

    8 February 2011, by

    La visualisation des images est restreinte par la largeur accordée par le design du site (dépendant du thème utilisé). Elles sont donc visibles sous un format réduit. Afin de profiter de l’ensemble de la place disponible sur l’écran de l’utilisateur, il est possible d’ajouter une fonctionnalité d’affichage de l’image dans une boite multimedia apparaissant au dessus du reste du contenu.
    Pour ce faire il est nécessaire d’installer le plugin "Mediabox".
    Configuration de la boite multimédia
    Dès (...)

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  • How to send large x264 NAL over RTMP?

    17 September 2017, by samgak

    I’m trying to stream video over RTMP using x264 and rtmplib in C++ on Windows.

    So far I have managed to encode and stream a test video pattern consisting of animated multi-colored vertical lines that I generate in code. It’s possible to start and stop the stream, and start and stop the player, and it works every time. However, as soon as I modify it to send encoded camera frames instead of the test pattern, the streaming becomes very unreliable. It only starts <20% of the time, and stopping and restarting doesn’t work.

    After searching around for answers I concluded that it must be because the NAL size is too large (my test pattern is mostly flat color so it encodes to a very small size), and there is an Ethernet packet limit of around 1400 bytes that affects it. So, I tried to make x264 only output NALs under 1200 bytes, by setting i_slice_max_size in my x264 setup:

    if (x264_param_default_preset(&amp;param, "veryfast", "zerolatency") &lt; 0)
    
    return false;
    
param.i_csp = X264_CSP_I420;
    
param.i_threads = 1;
    
param.i_width = width;  //set frame width
    
param.i_height = height;  //set frame height
    
param.b_cabac = 0;
    
param.i_bframe = 0;
    
param.b_interlaced = 0;
    
param.rc.i_rc_method = X264_RC_ABR;
    
param.i_level_idc = 21;
    
param.rc.i_bitrate = 128;
    
param.b_intra_refresh = 1;
    
param.b_annexb = 1;
    
param.i_keyint_max = 25;
    
param.i_fps_num = 15;
    
param.i_fps_den = 1;
    

    
param.i_slice_max_size = 1200;
    

    
if (x264_param_apply_profile(&amp;param, "baseline") &lt; 0)
    
    return false;

    This reduces the NAL size, but it doesn’t seem to make any difference to the reliability issues.

    I’ve also tried fragmenting the NALs, using this Java code and RFC 3984 (RTP Payload Format for H.264 Video) as a reference, but it doesn’t work at all (code below), the server says "stream has stopped" immediately after it starts. I’ve tried including and excluding the NAL header (with the timestamp etc) in each fragment or just the first, but it doesn’t work for me either way.

    I’m pretty sure my issue has to be with the NAL size and not PPS/SPS or anything like that (as in this question) or with my network connection or test server, because everything works fine with the test pattern.

    I’m sending NAL_PPS and NAL_SPS (only once), and all NAL_SLICE_IDR and NAL_SLICE packets. I’m ignoring NAL_SEI and not sending it.

    One thing that is confusing me is that the source code that I can find on the internet that does similar things to what I want doesn’t match up with what the RFC specifies. For example, RFC 3984 section 5.3 defines the NAL octet, which should have the NAL type in the lower 5 bits and the NRI in bits 5 and 6 (bit 7 is zero). The types NAL_SLICE_IDR and NAL_SLICE have values of 5 and 1 respectively, which are the ones in table 7-1 of this document (PDF) referenced by the RFC and also the ones output by x264. But the code that actually works sets the NAL octet to 39 (0x27) and 23 (0x17), for reasons unknown to me. When implementing fragmented NALs, I’ve tried both following the spec and using the values copied over from the working code, but neither works.

    Any help appreciated.

    void sendNAL(unsigned char* buf, int len)
    
{
    
    Logging::LogNumber("sendNAL", len);
    
    RTMPPacket * packet;
    
    long timeoffset = GetTickCount() - startTime;
    

    
    if (buf[2] == 0x00) { //00 00 00 01
    
        buf += 4;
    
        len -= 4;
    
    }
    
    else if (buf[2] == 0x01) { //00 00 01
    
        buf += 3;
    
        len -= 3;
    
    }
    
    else
    
    {
    
        Logging::LogStdString("INVALID x264 FRAME!");
    
    }
    
    int type = buf[0] &amp; 0x1f;   
    
    int maxNALSize = 1200;
    

    
    if (len &lt;= maxNALSize)
    
    {
    
        packet = (RTMPPacket *)malloc(RTMP_HEAD_SIZE + len + 9);
    
        memset(packet, 0, RTMP_HEAD_SIZE);
    

    
        packet->m_body = (char *)packet + RTMP_HEAD_SIZE;
    
        packet->m_nBodySize = len + 9;
    

    
        unsigned char *body = (unsigned char *)packet->m_body;
    
        memset(body, 0, len + 9);
    

    
        body[0] = 0x27;
    
        if (type == NAL_SLICE_IDR) {
    
            body[0] = 0x17;
    
        }
    

    
        body[1] = 0x01;   //nal unit
    
        body[2] = 0x00;
    
        body[3] = 0x00;
    
        body[4] = 0x00;
    

    
        body[5] = (len >> 24) &amp; 0xff;
    
        body[6] = (len >> 16) &amp; 0xff;
    
        body[7] = (len >> 8) &amp; 0xff;
    
        body[8] = (len) &amp; 0xff;
    

    
        memcpy(&amp;body[9], buf, len);
    

    
        packet->m_hasAbsTimestamp = 0;
    
        packet->m_packetType = RTMP_PACKET_TYPE_VIDEO;
    
        if (rtmp != NULL) {
    
            packet->m_nInfoField2 = rtmp->m_stream_id;
    
        }
    
        packet->m_nChannel = 0x04;
    
        packet->m_headerType = RTMP_PACKET_SIZE_LARGE;
    
        packet->m_nTimeStamp = timeoffset;
    

    
        if (rtmp != NULL) {
    
            RTMP_SendPacket(rtmp, packet, QUEUE_RTMP);
    
        }
    
        free(packet);
    
    }
    
    else
    
    {
    
        packet = (RTMPPacket *)malloc(RTMP_HEAD_SIZE + maxNALSize + 90);
    
        memset(packet, 0, RTMP_HEAD_SIZE);      
    

    
        // split large NAL into multiple smaller ones:
    
        int sentBytes = 0;
    
        bool firstFragment = true;
    
        while (sentBytes &lt; len)
    
        {
    
            // decide how many bytes to send in this fragment:
    
            int fragmentSize = maxNALSize;
    
            if (sentBytes + fragmentSize > len)
    
                fragmentSize = len - sentBytes;
    
            bool lastFragment = (sentBytes + fragmentSize) >= len;
    

    
            packet->m_body = (char *)packet + RTMP_HEAD_SIZE;
    
            int headerBytes = firstFragment ? 10 : 2;
    
            packet->m_nBodySize = fragmentSize + headerBytes;
    

    
            unsigned char *body = (unsigned char *)packet->m_body;
    
            memset(body, 0, fragmentSize + headerBytes);
    

    
            //key frame
    
            int NALtype = 0x27;
    
            if (type == NAL_SLICE_IDR) {
    
                NALtype = 0x17;
    
            }
    

    
            // Set FU-A indicator
    
            body[0] = (byte)((NALtype &amp; 0x60) &amp; 0xFF); // FU indicator NRI
    
            body[0] += 28; // 28 = FU - A (fragmentation unit A) see RFC: https://tools.ietf.org/html/rfc3984
    

    
            // Set FU-A header
    
            body[1] = (byte)(NALtype &amp; 0x1F);  // FU header type
    
            body[1] += (firstFragment ? 0x80 : 0) + (lastFragment ? 0x40 : 0); // Start/End bits
    

    
            body[2] = 0x01;   //nal unit
    
            body[3] = 0x00;
    
            body[4] = 0x00;
    
            body[5] = 0x00;
    

    
            body[6] = (len >> 24) &amp; 0xff;
    
            body[7] = (len >> 16) &amp; 0xff;
    
            body[8] = (len >> 8) &amp; 0xff;
    
            body[9] = (len) &amp; 0xff;
    

    
            //copy data
    
            memcpy(&amp;body[headerBytes], buf + sentBytes, fragmentSize);
    

    
            packet->m_hasAbsTimestamp = 0;
    
            packet->m_packetType = RTMP_PACKET_TYPE_VIDEO;
    
            if (rtmp != NULL) {
    
                packet->m_nInfoField2 = rtmp->m_stream_id;
    
            }
    
            packet->m_nChannel = 0x04;
    
            packet->m_headerType = RTMP_PACKET_SIZE_LARGE;
    
            packet->m_nTimeStamp = timeoffset;
    

    
            if (rtmp != NULL) {
    
                RTMP_SendPacket(rtmp, packet, TRUE);
    
            }
    

    
            sentBytes += fragmentSize;
    
            firstFragment = false;
    
        }
    

    
        free(packet);
    
    }
    
}

  • php shell_exec() command pop out error and permission denied ffmpeg

    19 October 2016, by user3711175

    This is the main index.php file where I run my code to generate a video thumbnail with ffmpeg but it has no lucks at all I have been searching online for a lot of solution but nothing comes out i will be very appreciate if you guys can help me out. The shell_exec() keep giving me error

    <form action="index.php" method="POST" enctype="multipart/form-data">
    
<input type="file" /><input type="submit" value="upload" />
    

    
</form>
    

    
&lt;?php
    

    
if(isset($_POST['submit'])){
    

    

    
$ffmpeg = "/Users/mac/Documents/ffmpeg/3.1.4/bin/ffmpeg";
    
$videoFile = $_FILES["file"]["tmp_name"];
    
$imageFile = "1.jpg";
    
$size = "320x240";
    
$getFromSecond = 5;
    
$cmd = "$ffmpeg -i $videoFile -an -ss $getFromSecond -s $size $imageFile 2>&amp;1";
    

    
    echo shell_exec($cmd);
    

    

    
echo shell_exec('whoami');
    
if(!shell_exec($cmd)){
    

    

    
    echo "thumbnail created";
    
}else{
    
    echo "error creating thumbnail";
    
}
    

    

    

    

    

    

    
}
    

    
?>

  • php shell_exec() command pop out error and permission denied ffmpeg

    3 June 2023, by user3711175

    This is the main index.php file where I run my code to generate a video thumbnail with ffmpeg but it has no lucks at all I have been searching online for a lot of solution but nothing comes out i will be very appreciate if you guys can help me out. The shell_exec() keep giving me error

    &#xA;&#xA;

    &#xA;&#xA;&#xA;&#xA;<form action="index.php" method="POST" enctype="multipart/form-data">&#xA;<input type="file" /><input type="submit" value="upload" />&#xA;&#xA;</form>&#xA;&#xA;&lt;?php&#xA;&#xA;if(isset($_POST[&#x27;submit&#x27;])){&#xA;&#xA;&#xA;$ffmpeg = "/Users/mac/Documents/ffmpeg/3.1.4/bin/ffmpeg";&#xA;$videoFile = $_FILES["file"]["tmp_name"];&#xA;$imageFile = "1.jpg";&#xA;$size = "320x240";&#xA;$getFromSecond = 5;&#xA;$cmd = "$ffmpeg -i $videoFile -an -ss $getFromSecond -s $size $imageFile 2>&amp;1";&#xA;&#xA;    echo shell_exec($cmd);&#xA;&#xA;&#xA;echo shell_exec(&#x27;whoami&#x27;);&#xA;if(!shell_exec($cmd)){&#xA;&#xA;&#xA;    echo "thumbnail created";&#xA;}else{&#xA;    echo "error creating thumbnail";&#xA;}&#xA;&#xA;&#xA;&#xA;&#xA;&#xA;&#xA;}&#xA;&#xA;?>&#xA;&#xA;&#xA;&#xA;

    &#xA;

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