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  • Publier sur MédiaSpip

    13 juin 2013

    Puis-je poster des contenus à partir d’une tablette Ipad ?
    Oui, si votre Médiaspip installé est à la version 0.2 ou supérieure. Contacter au besoin l’administrateur de votre MédiaSpip pour le savoir

  • 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 (...)

Sur d’autres sites (9270)

  • 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.

  • Screencasting with hardware-accelerated gnome-3 [closed]

    30 octobre 2012, par Jeroen

    I am running Ubuntu 12.04 with gnome 3 shell, and I would like to create a screencast. I have tried using recordMyDesktop, Kazam Screencaster, and ffmpeg but all suffer from the same problem, which I think has to do with hardware acceleration in Gnome 3. The recorded videos all get very glitchy with blue space for all operations that use some sort of effect. Here is an example recording : http://www.stat.ucla.edu/ jeroen/files/screencast.mkv.

    The only method that does not seem to suffer from this, is the (largely undocumented) CTRL+SHIFT+R shortcut in gnome 3 that will start a recording. However, this feature is very buggy otherwise and often crashes when I enable audio input.

    My machine has a GeForce GT 120 with Apple LED Cinema monitor. I am using the proprietary nvidia drivers that ship with Ubuntu 12.04. Is there any way I can record the video as it appears on my screen ? I know I can avoid the problem by switching to gnome2 or unity 2d or anything that does not use effects, but I would prefer to make the recordings in my regular gnome 3 environment.

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