Recherche avancée

Médias (0)

Mot : - Tags -/interaction

Aucun média correspondant à vos critères n’est disponible sur le site.

Autres articles (112)

  • Personnaliser en ajoutant son logo, sa bannière ou son image de fond

    5 septembre 2013, par

    Certains thèmes prennent en compte trois éléments de personnalisation : l’ajout d’un logo ; l’ajout d’une bannière l’ajout d’une image de fond ;

  • Websites made ​​with MediaSPIP

    2 mai 2011, par

    This page lists some websites based on MediaSPIP.

  • Creating farms of unique websites

    13 avril 2011, par

    MediaSPIP platforms can be installed as a farm, with a single "core" hosted on a dedicated server and used by multiple websites.
    This allows (among other things) : implementation costs to be shared between several different projects / individuals rapid deployment of multiple unique sites creation of groups of like-minded sites, making it possible to browse media in a more controlled and selective environment than the major "open" (...)

Sur d’autres sites (14984)

  • Converting uint8_t data to AVFrame with FFmpeg

    30 octobre 2017, par J.Lefebvre

    I am currently working in C++ with the Autodesk 3DStudio Max 2014 SDK (toolset 100) and the Ffmpeg library in Visual Studio 2015 and trying to convert a DIB (Device Independent Bitmap) to uint8_t pointer array and then convert these data to an AVFrame.

    I don’t have any errors, but my video is still black and without meta data.
    (no time display, etc)

    I made approximatively the same with a Visual Studio Console application to convert jpeg image sequence from disk and this is working fine.
    (The only difference is that instead of converting jpeg to AVFrame with the Ffmpeg library, I try to convert raw data to an AVFrame.)

    So I think the problem could be either on the DIB conversion to the uint8_t data or the uint8_t data to the AVFrame.
    (The second is more plausible, because I used the SFML library to display a window with my rgb uint8_t* data for debuging and it is working fine.)

    I first initialize the ffmpeg library :

    This function is called once at the beginning.

    int Converter::Initialize(AVCodecID codec_id, int width, int height, int fps, const char *filename)
    {
       avcodec_register_all();
       av_register_all();

       AVCodec *codec;
       inputFrame = NULL;
       codecContext = NULL;
       pkt = NULL;
       file = NULL;
       outputFilename = new char[strlen(filename)]();
       *outputFilename = '\0';
       strcpy(outputFilename, filename);

       int ret;

       //Initializing AVCodecContext and getting PixelFormat supported by encoder
       codec = avcodec_find_encoder(codec_id);
       if (!codec)
           return 1;

       AVPixelFormat pixFormat = codec->pix_fmts[0];
       codecContext = avcodec_alloc_context3(codec);
       if (!codecContext)
           return 1;

       codecContext->bit_rate = 400000;
       codecContext->width = width;
       codecContext->height = height;
       codecContext->time_base.num = 1;
       codecContext->time_base.den = fps;
       codecContext->gop_size = 10;
       codecContext->max_b_frames = 1;
       codecContext->pix_fmt = pixFormat;

       if (codec_id == AV_CODEC_ID_H264)
           av_opt_set(codecContext->priv_data, "preset", "slow", 0);

       //Actually opening the encoder
       if (avcodec_open2(codecContext, codec, NULL) < 0)
           return 1;

       file = fopen(outputFilename, "wb");
       if (!file)
           return 1;

       inputFrame = av_frame_alloc();
       inputFrame->format = codecContext->pix_fmt;
       inputFrame->width = codecContext->width;
       inputFrame->height = codecContext->height;

       ret = av_image_alloc(inputFrame->data, inputFrame->linesize, codecContext->width, codecContext->height, codecContext->pix_fmt, 32);

       if (ret < 0)
           return 1;

       return 0;
    }

    Then for each frame, I get the DIB and convert to a uint8_t* it with this function :

    uint8_t* Util::ToUint8_t(RGBQUAD *data, int width, int height)
    {
       uint8_t* buf = (uint8_t*)data;

       int imageSize = width * height;
       size_t rgbquad_size = sizeof(RGBQUAD);
       size_t total_bytes = imageSize * rgbquad_size;
       uint8_t * pCopyBuffer = new uint8_t[total_bytes];

       for (int x = 0; x < width; x++)
       {
           for (int y = 0; y < height; y++)
           {
               int index = (x + width * y) * rgbquad_size;
               int invertIndex = (x + width* (height - y - 1)) * rgbquad_size;

               //BGRA to RGBA
               pCopyBuffer[index] = buf[invertIndex + 2];
               pCopyBuffer[index + 1] = buf[invertIndex + 1];
               pCopyBuffer[index + 2] = buf[invertIndex];
               pCopyBuffer[index + 3] = 0xFF;
           }
       }

       return pCopyBuffer;
    }

    void GetDIBBuffer(Interface* ip, BITMAPINFO *bmi, uint8_t** outBuffer)
    {
       int size;

       ViewExp& view = ip->GetActiveViewExp();

       view.getGW()->getDIB(NULL, &size);

       bmi = (BITMAPINFO *)malloc(size);
       BITMAPINFOHEADER *bmih = (BITMAPINFOHEADER *)bmi;
       view.getGW()->getDIB(bmi, &size);

       uint8_t * pCopyBuffer = Util::ToUint8_t(bmi->bmiColors, bmih->biWidth, bmih->biHeight);

       *outBuffer = pCopyBuffer;
    }

    This function is used to get the DIB :

    void GetViewportDIB(Interface* ip, BITMAPINFO *bmi, BITMAPINFOHEADER *bmih, BitmapInfo biFile, Bitmap *map)
    {
       int size;

       if (!biFile.Name()[0])
           return;

       ViewExp& view = ip->GetActiveViewExp();

       view.getGW()->getDIB(NULL, &size);

       bmi = (BITMAPINFO *)malloc(size);
       bmih = (BITMAPINFOHEADER *)bmi;

       view.getGW()->getDIB(bmi, &size);

       biFile.SetWidth((WORD)bmih->biWidth);
       biFile.SetHeight((WORD)bmih->biHeight);
       biFile.SetType(BMM_TRUE_32);

       map = TheManager->Create(&biFile);
       map->OpenOutput(&biFile);
       map->FromDib(bmi);
       map->Write(&biFile);
       map->Close(&biFile);
    }

    And after the conversion to AVFrame and video encoding :

    The EncodeFromMem function is call each frame.

    int Converter::EncodeFromMem(const char *outputDir, int frameNumber, uint8_t* data)
    {
       int ret;

       inputFrame->pts = frameNumber;
       EncodeFrame(data, codecContext, inputFrame, &pkt, file);

       return 0;
    }

    static void RgbToYuv(uint8_t *rgb, AVCodecContext *c, AVFrame *frame)
    {
       struct SwsContext *swsCtx = NULL;
       const int in_linesize[1] = { 3 * c->width };// RGB stride
       swsCtx = sws_getCachedContext(swsCtx, c->width, c->height, AV_PIX_FMT_RGB24, c->width, c->height, AV_PIX_FMT_YUV420P, 0, 0, 0, 0);
       sws_scale(swsCtx, (const uint8_t * const *)&rgb, in_linesize, 0, c->height, frame->data, frame->linesize);
    }

    static void EncodeFrame(uint8_t *rgb, AVCodecContext *c, AVFrame *frame, AVPacket **pkt, FILE *file)
    {
       int ret, got_output;

       RgbToYuv(rgb, c, frame);

       *pkt = av_packet_alloc();
       av_init_packet(*pkt);
       (*pkt)->data = NULL;
       (*pkt)->size = 0;

       ret = avcodec_encode_video2(c, *pkt, frame, &got_output);
       if (ret < 0)
       {
           fprintf(stderr, "Error encoding frame/n");
           exit(1);
       }
       if (got_output)
       {
           fwrite((*pkt)->data, 1, (*pkt)->size, file);
           av_packet_unref(*pkt);
       }
    }

    To finish I have a function that write the packets and free the memory :
    This function is called once at the end of the time range.

    int Converter::Finalize()
    {
       int ret, got_output;
       uint8_t endcode[] = { 0, 0, 1, 0xb7 };

       /* get the delayed frames */
       do
       {
           fflush(stdout);
           ret = avcodec_encode_video2(codecContext, pkt, NULL, &got_output);
           if (ret < 0)
           {
               fprintf(stderr, "Error encoding frame/n");
               return 1;
           }
           if (got_output)
           {
               fwrite(pkt->data, 1, pkt->size, file);
               av_packet_unref(pkt);
           }
       } while (got_output);

       fwrite(endcode, 1, sizeof(endcode), file);
       fclose(file);

       avcodec_close(codecContext);
       av_free(codecContext);

       av_frame_unref(inputFrame);
       av_frame_free(&inputFrame);
       //av_freep(&inputFrame->data[0]); //Crash

       delete outputFilename;
       outputFilename = 0;

       return 0;
    }

    EDIT :

    I modify my RgbToYuv function and create another one to convert back the yuv frame to an rgb one.

    This not really solve the problem, but maybe focus the problem on the conversion from YuvToRgb.

    This is the result of the conversion from YUV to RGB :

     ![YuvToRgb result] : https://img42.com/kHqpt+

    static void YuvToRgb(AVCodecContext *c, AVFrame *frame)
    {
       struct SwsContext *img_convert_ctx = sws_getContext(c->width, c->height, AV_PIX_FMT_YUV420P, c->width, c->height, AV_PIX_FMT_RGB24, SWS_BICUBIC, NULL, NULL, NULL);
       AVFrame * rgbPictInfo = av_frame_alloc();
       avpicture_fill((AVPicture*)rgbPictInfo, *(frame)->data, AV_PIX_FMT_RGB24, c->width, c->height);
       sws_scale(img_convert_ctx, frame->data, frame->linesize, 0, c->height, rgbPictInfo->data, rgbPictInfo->linesize);

       Util::DebugWindow(c->width, c->height, rgbPictInfo->data[0]);
    }
    static void RgbToYuv(uint8_t *rgb, AVCodecContext *c, AVFrame *frame)
    {
       AVFrame * rgbPictInfo = av_frame_alloc();
       avpicture_fill((AVPicture*)rgbPictInfo, rgb, AV_PIX_FMT_RGBA, c->width, c->height);

       struct SwsContext *swsCtx = sws_getContext(c->width, c->height, AV_PIX_FMT_RGBA, c->width, c->height, AV_PIX_FMT_YUV420P, SWS_BICUBIC, NULL, NULL, NULL);
       avpicture_fill((AVPicture*)frame, rgb, AV_PIX_FMT_YUV420P, c->width, c->height);    
       sws_scale(swsCtx, rgbPictInfo->data, rgbPictInfo->linesize, 0, c->height, frame->data, frame->linesize);

       YuvToRgb(c, frame);
    }
  • ffmpeg encoder streaming issues

    8 août 2017, par bobsingh1

    I am trying to build ffmpeg encoder on linux. I started with a custom built server Dual 1366 2.6 Ghz Xeon CPUs (6 cores) with 16 GB RAM with Ubuntu 16.04 minimal install. Built ffmpeg with h264 and aac. I am taking live source OTA channels and encoding/streaming them with following parameters

    -vcodec libx264 -preset superfast -crf 25 -x264opts keyint=60:min-keyint=60:scenecut=-1 -bufsize 7000k -b:v 6000k -maxrate 6300k -muxrate 6000k -s 1920x1080 -format yuv420p -g 60 -sn -c:a aac -b:a 384k -ar 44100

    And I am able to successfully udp out using mpegts. My problem starts with 5th stream. The server can handle four streams and as soon as I introduce 5th stream I start seeing hiccups in output. Looking at my cpu usage using top I still see only 65% to 75% usage with occasional 80% hit. Memory usage is well within acceptable parameters. So I am wondering either top is not giving me accurate cpu usage or something is not right with ffmpeg. The server is isolated for udp in/out on a 1 Gbps network.

    I decided to up the cpu power and installed two 3.5 Ghz CPUs (6 cores) thinking it was perhaps the cpu clock. To my surprise the results were no different. So now I am wondering is there some built in limit I am hitting when I process at 1080p. If I change the resolution to 720p it is able to process 8 streams but 720 is not acceptable.
    My target is 10 1080p streams per server.
    So my questions are
    1. If I use a quad motherboard and up the cpu count to 4 (6 or 8 cores) will I get 10 1080p streams ? Is there any theoretical max I can go with ffmpeg per machine ?
    2. Do cores matter more or does clock matter more ?
    3. Any suggestions in improvement with my options. I have tried ultrafast preset but the output quality is unacceptable.

    Thanks in advance

  • Plex DVR File Rename on FFMPEG Encoding

    11 juillet 2021, par Brent Johnson

    I'm currently using a bash shell script to encode all of my Plex DVR recordings to H.264 using FFMPEG. I'm using this little for loop I found online to encode all of the files in a single directory :

    


    for i in *.ts;
    do echo "$i" && ffmpeg -i "$i" -vf yadif -c:v libx264 -preset veryslow -crf 22 -y "/mnt/d/Video/DVR Stash/Seinfeld/${i%.*}.mp4";
done


    


    This has served its purposes well but in the process I would like to rename the file to my preferred naming convention so that the original filename Seinfeld (1989) - S01E01 - Pilot.ts is renamed to Seinfeld S01 E01 Pilot.mp4 in the encoded file. While I am already using a regular expression to change the .ts extension to .mp4, but I'm no expert with regex, especially in the bash shell so any help would be appreciated.

    


    For anyone that's interested in my Plex setup, I'm using an old machine running Linux Mint as my dedicated DVR and actually accessing it over the network with my daily driver which is a gaming machine, so more processing power for video encodes. While that one is a Windows machine, I'm using the Ubuntu bash under WSL2 to run my script, as I prefer it over the Windows command prompt or Powershell (my day job is a web developer on a company issued Mac). So here's a sample of my code for anyone that might consider doing something similar.

    


    if [[ -d "/mnt/sambashare/Seinfeld (1989)" ]]
then
    cd "/mnt/sambashare/Seinfeld (1989)"
    echo "Seinfeld"
    for dir in */; do
        echo "$dir/"
        cd "$dir"
        for i in *.ts;
            do echo "$i" && ffmpeg -i "$i" -vf yadif -c:v libx264 -preset veryslow -crf 22 -y "/mnt/d/Video/DVR Stash/Seinfeld/${i%.*}.mp4";
        done
        cd ..
    done
fi


    


    While I've considered doing a for loop for all shows, for now I am doing each show like this individually as there are a few shows I have custom encoding settings for