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  • Participer à sa traduction

    10 avril 2011

    Vous pouvez nous aider à améliorer les locutions utilisées dans le logiciel ou à traduire celui-ci dans n’importe qu’elle nouvelle langue permettant sa diffusion à de nouvelles communautés linguistiques.
    Pour ce faire, on utilise l’interface de traduction de SPIP où l’ensemble des modules de langue de MediaSPIP sont à disposition. ll vous suffit de vous inscrire sur la liste de discussion des traducteurs pour demander plus d’informations.
    Actuellement MediaSPIP n’est disponible qu’en français et (...)

  • Websites made ​​with MediaSPIP

    2 mai 2011, par

    This page lists some websites based on MediaSPIP.

  • Possibilité de déploiement en ferme

    12 avril 2011, par

    MediaSPIP peut être installé comme une ferme, avec un seul "noyau" hébergé sur un serveur dédié et utilisé par une multitude de sites différents.
    Cela permet, par exemple : de pouvoir partager les frais de mise en œuvre entre plusieurs projets / individus ; de pouvoir déployer rapidement une multitude de sites uniques ; d’éviter d’avoir à mettre l’ensemble des créations dans un fourre-tout numérique comme c’est le cas pour les grandes plate-formes tout public disséminées sur le (...)

Sur d’autres sites (10742)

  • HLS folder is not getting created in NGINX-RTMP

    15 juin 2016, par Sai Krishna

    This is my nginx configuration file. I am using OBS to stream some media files to my nginx server. The /tmp/live/ folder is getting created but /tmp/live/1080/index.m3u8 is not getting created.

    https://gist.github.com/Eta-Meson/2f88a91ad57704247dcc5c9cf4a89e35

    I have kept my configuration file in this gist.

  • FFMPEG : How to reduce black sides in a vertical video

    2 juin 2016, par hari92114

    I’m using FFMPEG to rotate a vertical video using the below command

    ffmpeg -i input.mp4 -vf 'transpose=1,scale=-1:1080,pad=1920:1080:656:0,setsar=1' -metadata:s:v:0 rotate=0  output.mp4

    While doing the playback ,most of the screen is occupied by black sides which FFMPEG has added.

    Output image : roated-video

    Is there any provision to reduce them ?

  • H.264 muxing to MP4 from CCTV (HW) encoder using ffmpeg library in C / C++, how to fetch AVCodecContext::extradata

    26 mai 2016, par Dom

    I am trying to mux a video to mp4 file from packets received via SDK API of CCTV camera. The stream from CCTV seems to consist of packets of h264 I and P-frames only (no B-frames).

    The problem is, that the file is not playable in Daum PotPlayer when I leave the AVCodecContext::extradata empty, however, I can play the file in VLC. If I feed the extra data (probably not correctly - I just copy the first 50 bytes from the packet received from the HW encoder), the file is playable in PotPlayer, but not in VLC.

    I do not know, how to prepare the extradata properly.

    The code below shows the muxing.

    void WriteVideo()
    
{
    
    AVFormatContext* formatContext = nullptr;
    
    AVStream* stream = nullptr;
    

    
    int ret = 0;
    

    
    ret = avformat_alloc_output_context2(&formatContext, nullptr, "mp4", OUTPUT_V_FILE_NAME);
    
    if (ret < 0)
    
    {
    
        fprintf(stderr, "Error occurred when allocating output context: %d\n", ret);
    
        return;
    
    }
    

    
    stream = avformat_new_stream(formatContext, nullptr);
    
    if (!stream)
    
    {
    
        avformat_free_context(formatContext);
    
        formatContext = nullptr;
    
        fprintf(stderr, "Error occurred creating new stream");
    
        return;
    
    }
    

    
    stream->codec->codec_tag = 0;
    

    
    if (formatContext->oformat->flags & AVFMT_GLOBALHEADER)
    
    {
    
        stream->codec->flags |= CODEC_FLAG_GLOBAL_HEADER;
    
    }
    

    

    
    stream->codec->codec_type = AVMEDIA_TYPE_VIDEO;
    
    stream->codec->codec_id = AV_CODEC_ID_H264;
    
    stream->codec->pix_fmt = AV_PIX_FMT_YUV420P;
    
    stream->codec->bit_rate = 4096000; // 8192000; // 4096000; // 384000;
    
    stream->codec->width = 1920; // 352
    
    stream->codec->height = 1080; // 288
    
    stream->codec->gop_size = 50;
    

    
    AVRational tb;
    
    tb.num = 1;
    
    tb.den = 25;
    
    stream->codec->time_base = tb;
    
    //stream->codec->field_order = AVFieldOrder::AV_FIELD_UNKNOWN;
    
    //stream->codec->color_primaries = AVColorPrimaries::AVCOL_PRI_BT470BG;
    
    //stream->codec->color_trc = AVColorTransferCharacteristic::AVCOL_TRC_GAMMA22;
    
    //stream->codec->colorspace = AVColorSpace::AVCOL_SPC_BT470BG;
    
    //stream->codec->chroma_sample_location = AVChromaLocation::AVCHROMA_LOC_CENTER;
    
    AVRational aratio;
    
    aratio.num = 1;
    
    aratio.den = 1;
    
    stream->codec->sample_aspect_ratio = aratio;
    
    // stream->codec->delay = 0;
    
    // stream->codec->color_range = AVColorRange::AVCOL_RANGE_MPEG;
    

    
    av_dump_format(formatContext, 0, formatContext->filename, 1);
    

    
    if (!(formatContext->oformat->flags & AVFMT_NOFILE))
    
    {
    
        if (avio_open(&formatContext->pb, formatContext->filename, AVIO_FLAG_WRITE) < 0)
    
        {
    
            avformat_free_context(formatContext);
    
            formatContext = nullptr;
    
            fprintf(stderr, "Error occurred when opening output file.");
    
            return;
    

    
        }
    
    }
    

    
    avformat_write_header(formatContext, nullptr);
    

    
    int frameIdx = 0;
    
    int pts = 0;
    
    int dts = 0;
    
    int pkt_pos = 0;
    
    int size = static_cast<int>(tmpRawFrameBuffer.size());
    

    
    AVPacket pkt = { 0 };
    
    av_init_packet(&amp;pkt);
    

    
    while (frameIdx &lt; size)
    
    {
    
        pkt.data = tmpRawFrameBuffer[frameIdx];
    
        pkt.size = tmpRawFrameSizes[frameIdx];
    

    
        // debug purphose start
    
        FILE* f;
    
        char filename[MAX_PATH];
    
        sprintf_s(filename, MAX_PATH, OUTPUT_PACKET_FILE_PATTERN_NAME, frameIdx);
    
        auto err = fopen_s(&amp;f, filename, "wb");
    
        if (err != 0)
    
        {
    
            fprintf(stderr, "Could not open %s\n", OUTPUT_V_FILE_NAME);
    
            exit(1);
    
        }
    

    
        fflush(stdout);
    
        fwrite(pkt.data, 1, pkt.size, f);
    
        fclose(f);
    
        // debug purphose end
    

    
        if (tmpRawFrameTypes[frameIdx] == VIDEO_I_FRAME)
    
        {
    
            pkt.flags |= AV_PKT_FLAG_KEY;
    
            stream->codec->extradata_size = 50;
    
            stream->codec->extradata = (uint8_t*)av_malloc(stream->codec->extradata_size);
    
            memcpy(stream->codec->extradata, pkt.data, stream->codec->extradata_size);
    
        }
    
        pkt.pts = pts++;
    
        pkt.dts = dts++;
    
        /* rescale output packet timestamp values from codec to stream timebase */
    
        // av_packet_rescale_ts(&amp;pkt, stream->codec->time_base, stream->time_base);
    
        pkt.pts = av_rescale_q(pkt.pts, stream->codec->time_base, stream->time_base);
    
        pkt.dts = av_rescale_q(pkt.dts, stream->codec->time_base, stream->time_base);
    
        pkt.duration = 512; // should be calculated (derived from FPS 25, and 12800)
    
        pkt.pos = -1;
    
        pkt.stream_index = stream->index;
    

    
        auto ret = av_write_frame(formatContext, &amp;pkt);
    
        if (ret &lt; 0)
    
        {
    
            fprintf(stderr, "Error while writing video frame: %d\n", ret);
    
            break;
    
        }
    
        av_packet_unref(&amp;pkt);
    
        ++frameIdx;
    
    }
    

    
    if (formatContext)
    
    {
    
        av_write_trailer(formatContext);
    
        if (!(formatContext->oformat->flags &amp; AVFMT_NOFILE)) avio_close(formatContext->pb); // close the output file
    
        avformat_free_context(formatContext);
    
        formatContext = nullptr;
    
    }
    
}
    
</int>

    It seems, the packet from camera (buffered in tmpRawFrameBuffer vector) contains some headers, but I am not able to parse them, I do not understand the meaning of the header.

    The first bytes of the I-frame packet looks like the dump bellow :

    00 00 01 FC 02 19 F0 87 A0 23 73 41 B6 C0 01 00
    
00 00 00 01 67 4D 00 2A 95 A8 1E 00 89 F9 61 00
    
00 03 00 01 00 00 03 00 32 84 00 00 00 01 68 EE 
    
3C 80 00 00 00 01 06 E5 01 19 80 00 00 00 01 65 
    
B8 00 00 08 C7 B0 23 FF F7 80 EE FE 63 B6 FB F5
    
...

    The first bytes of the first P-frame :

    00 00 01 FD E5 24 00 00 00 00 00 01 61 E0 22 27 
    
FF D6 B0 D7 A4 2B 71 6B 19 C5 87 CA BB 8B BF 60 
    
14 59 B4 00 CC BC 0F C0 9E FD 84 B5 FB C4 83 DB 
    
5A 8B 80 FC EC D6 33 6D DE 10 96 6F 31 41 86 5C 
    
D4 22 F9 33 48 5B CE 77 38 17 0C D6 DD C7 6C E8
    
...

    first bytes of next P-frame :

    00 00 01 FD 5E 2F 00 00 00 00 00 01 61 E0 42 2F 
    
FF E7 06 DD 3C 66 26 15 94 93 7A F1 30 8A 6D B8 
    
AD DD 6B 0F 38 89 1D 1B 5C AC 44 6A D7 D1 21 3B 
    
E2 29 F8 14 BB 98 1C 06 4D B6 10 BB DB B9 CA 4F 
    
0B ED B1 A9 06 78 8C EC 06 6D 9F 4F 79 0C 35 5B
    
...

    ...

    begining of next I-frame :

    00 00 01 FC 02 19 F0 87 A2 23 73 41 75 89 01 00 
    
00 00 00 01 67 4D 00 2A 95 A8 1E 00 89 F9 61 00 
    
00 03 00 01 00 00 03 00 32 84 00 00 00 01 68 EE 
    
3C 80 00 00 00 01 06 E5 01 1B 80 00 00 00 01 65 
    
B8 00 00 0F 07 F0 7F F6 6C 69 43 0F F0 28 DF 97
    
...

    Does anybody know, how to fill correctly the extradata ? I just made a copy of first 50 bytes, but it seems, this is not correct.

    Probably the headers are (AUD)(SPS)(PPS)(I-Slice)(PPS)(P-Slice)(PPS)(P-Slice) ... (AUD)(SPS)(PPS)(I-Slice) (http://stackoverflow.com/a/20686267/1699328), however, I do not know, how to extract data for the

    stream->codec->extradata

    I tried to get some inspiration in this post H.264 muxed to MP4 using libavformat not playing back, but I am not able to figure out what are values of spsFrameLen, ppsFrameLen and spsFrame.

    The result of the muxer (first and last bytes of the mp4 file) :

    00 00 00 20 66 74 79 70 69 73 6F 6D 00 00 02 00 
    
69 73 6F 6D 69 73 6F 32 61 76 63 31 6D 70 34 31 
    
00 00 00 08 66 72 65 65 00 26 2E 6D 6D 64 61 74 
    
00 00 00 0D FC 02 19 F0 87 A0 23 73 41 B6 C0 01 
    
00 00 00 00 16 67 4D 00 2A 95 A8 1E 00 89 F9 61 
    
00 00 03 00 01 00 00 03 00 32 84 00 00 00 04 68 
    
EE 3C 80 00 00 00 05 06 E5 01 19 80 00 01 C0 87 
    
65 B8 00 00 08 C7 B0 23 FF F7 80 EE FE 63 B6 FB 
    
F5 97 A8 6B 48 39 61 99 FD 99 27 41 F2 78 54 EE 
    
D1 38 8E E8 18 DD 05 E4 BA F4 EB 69 CF 91 5C 34
    
...
    
...
    
...
    
95 B8 D8 D4 C3 AF A1 BA AC 28 F0 D4 D4 7C 48 9A 
    
0C A6 8C 4C 98 00 00 05 1E 6D 6F 6F 76 00 00 00 
    
6C 6D 76 68 64 00 00 00 00 00 00 00 00 00 00 00 
    
00 00 00 03 E8 00 00 13 B0 00 01 00 00 01 00 00 
    
00 00 00 00 00 00 00 00 00 00 01 00 00 00 00 00 
    
00 00 00 00 00 00 00 00 00 00 01 00 00 00 00 00 
    
00 00 00 00 00 00 00 00 00 40 00 00 00 00 00 00 
    
00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 
    
00 00 00 00 00 00 00 00 02 00 00 04 48 74 72 61 
    
6B 00 00 00 5C 74 6B 68 64 00 00 00 03 00 00 00 
    
00 00 00 00 00 00 00 00 01 00 00 00 00 00 00 13 
    
B0 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 
    
00 00 01 00 00 00 00 00 00 00 00 00 00 00 00 00 
    
00 00 01 00 00 00 00 00 00 00 00 00 00 00 00 00 
    
00 40 00 00 00 07 80 00 00 04 38 00 00 00 00 00 
    
24 65 64 74 73 00 00 00 1C 65 6C 73 74 00 00 00 
    
00 00 00 00 01 00 00 13 B0 00 00 00 00 00 01 00 
    
00 00 00 03 C0 6D 64 69 61 00 00 00 20 6D 64 68 
    
64 00 00 00 00 00 00 00 00 00 00 00 00 00 00 32 
    
00 00 00 FC 00 55 C4 00 00 00 00 00 2D 68 64 6C 
    
72 00 00 00 00 00 00 00 00 76 69 64 65 00 00 00 
    
00 00 00 00 00 00 00 00 00 56 69 64 65 6F 48 61 
    
6E 64 6C 65 72 00 00 00 03 6B 6D 69 6E 66 00 00 
    
00 14 76 6D 68 64 00 00 00 01 00 00 00 00 00 00 
    
00 00 00 00 00 24 64 69 6E 66 00 00 00 1C 64 72 
    
65 66 00 00 00 00 00 00 00 01 00 00 00 0C 75 72 
    
6C 20 00 00 00 01 00 00 03 2B 73 74 62 6C 00 00 
    
00 93 73 74 73 64 00 00 00 00 00 00 00 01 00 00 
    
00 83 61 76 63 31 00 00 00 00 00 00 00 01 00 00 
    
00 00 00 00 00 00 00 00 00 00 00 00 00 00 07 80 
    
04 38 00 48 00 00 00 48 00 00 00 00 00 00 00 01 
    
00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 
    
00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 
    
00 18 FF FF 00 00 00 2D 61 76 63 43 01 4D 00 2A 
    
FF E1 00 16 67 4D 00 2A 95 A8 1E 00 89 F9 61 00 
    
00 03 00 01 00 00 03 00 32 84 01 00 04 68 EE 3C 
    
80 00 00 00 18 73 74 74 73 00 00 00 00 00 00 00 
    
01 00 00 00 7E 00 00 02 00 00 00 00 1C 73 74 73 
    
73 00 00 00 00 00 00 00 03 00 00 00 01 00 00 00 
    
33 00 00 00 65 00 00 00 34 73 74 73 63 00 00 00 
    
00 00 00 00 03 00 00 00 01 00 00 00 3B 00 00 00 
    
01 00 00 00 02 00 00 00 37 00 00 00 01 00 00 00 
    
03 00 00 00 0C 00 00 00 01 00 00 02 0C 73 74 73 
    
7A 00 00 00 00 00 00 00 00 00 00 00 7E 00 01 C0 
    
C7 00 00 24 EE 00 00 2F 67 00 00 1D 83 00 00 2E 
    
8F 00 00 30 B6 00 00 2F 44 00 00 2F 50 00 00 34 
    
6B 00 00 30 BE 00 00 31 0C 00 00 31 E7 00 00 30 
    
EA 00 00 31 4E 00 00 31 A8 00 00 32 21 00 00 31 
    
E6 00 00 31 B5 00 00 31 14 00 00 31 AF 00 00 31 
    
9D 00 00 33 60 00 00 32 11 00 00 32 4C 00 00 31 
    
F0 00 00 32 91 00 00 43 43 00 00 44 29 00 00 44 
    
EC 00 00 44 20 00 00 44 86 00 00 45 AD 00 00 47 
    
47 00 00 46 9F 00 00 46 D9 00 00 47 BE 00 00 48 
    
CD 00 00 3E 50 00 00 40 98 00 00 41 0E 00 00 40 
    
43 00 00 41 07 00 00 41 BB 00 00 41 FF 00 00 30 
    
5E 00 00 33 C7 00 00 34 B7 00 00 33 F1 00 00 33 
    
0D 00 00 32 DB 00 01 89 86 00 00 3B E1 00 00 3C 
    
55 00 00 3C 64 00 00 3C B7 00 00 3C FD 00 00 3E 
    
54 00 00 3E C5 00 00 3E 1C 00 00 3E 94 00 00 3E 
    
44 00 00 3E D7 00 00 3F CC 00 00 3E D6 00 00 40 
    
00 00 00 40 4D 00 00 40 04 00 00 3F A9 00 00 40 
    
82 00 00 41 0F 00 00 41 64 00 00 41 E5 00 00 42 
    
1E 00 00 42 2C 00 00 42 80 00 00 42 4D 00 00 43 
    
9F 00 00 43 DA 00 00 44 45 00 00 44 21 00 00 44 
    
B7 00 00 45 22 00 00 45 E3 00 00 45 BF 00 00 46 
    
18 00 00 47 4B 00 00 45 05 00 00 47 34 00 00 46 
    
60 00 00 46 97 00 00 46 66 00 00 46 29 00 00 46 
    
38 00 00 47 1D 00 00 47 42 00 00 47 18 00 00 47 
    
13 00 00 46 52 00 00 47 48 00 00 46 F8 00 01 BE 
    
E3 00 00 3F 56 00 00 3B 32 00 00 38 F8 00 00 37 
    
56 00 00 36 2D 00 00 35 DA 00 00 34 6B 00 00 3E 
    
BE 00 00 3E B5 00 00 3F 33 00 00 3F AC 00 00 3F 
    
38 00 00 42 32 00 01 1B DC 00 01 80 50 00 01 14 
    
06 00 00 C2 BB 00 00 96 12 00 00 6D EC 00 00 54 
    
E6 00 00 3A AC 00 00 32 00 00 00 2F 0A 00 00 2D 
    
F1 00 00 1B 7F 00 00 00 1C 73 74 63 6F 00 00 00 
    
00 00 00 00 03 00 00 00 30 00 0F DD AB 00 1F 7D 
    
9E 00 00 00 62 75 64 74 61 00 00 00 5A 6D 65 74 
    
61 00 00 00 00 00 00 00 21 68 64 6C 72 00 00 00 
    
00 00 00 00 00 6D 64 69 72 61 70 70 6C 00 00 00 
    
00 00 00 00 00 00 00 00 00 2D 69 6C 73 74 00 00 
    
00 25 A9 74 6F 6F 00 00 00 1D 64 61 74 61 00 00 
    
00 01 00 00 00 00 4C 61 76 66 35 37 2E 32 33 2E 
    
31 30 30

    Thanks a lot for any advices.

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