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  • Des sites réalisés avec MediaSPIP

    2 mai 2011, par

    Cette page présente quelques-uns des sites fonctionnant sous MediaSPIP.
    Vous pouvez bien entendu ajouter le votre grâce au formulaire en bas de page.

  • Librairies et binaires spécifiques au traitement vidéo et sonore

    31 janvier 2010, par

    Les logiciels et librairies suivantes sont utilisées par SPIPmotion d’une manière ou d’une autre.
    Binaires obligatoires FFMpeg : encodeur principal, permet de transcoder presque tous les types de fichiers vidéo et sonores dans les formats lisibles sur Internet. CF ce tutoriel pour son installation ; Oggz-tools : outils d’inspection de fichiers ogg ; Mediainfo : récupération d’informations depuis la plupart des formats vidéos et sonores ;
    Binaires complémentaires et facultatifs flvtool2 : (...)

  • Changer son thème graphique

    22 février 2011, par

    Le thème graphique ne touche pas à la disposition à proprement dite des éléments dans la page. Il ne fait que modifier l’apparence des éléments.
    Le placement peut être modifié effectivement, mais cette modification n’est que visuelle et non pas au niveau de la représentation sémantique de la page.
    Modifier le thème graphique utilisé
    Pour modifier le thème graphique utilisé, il est nécessaire que le plugin zen-garden soit activé sur le site.
    Il suffit ensuite de se rendre dans l’espace de configuration du (...)

Sur d’autres sites (5601)

  • ffmpeg-python crossfade transition for unknown number of photos

    28 septembre 2020, par Saya

    I want to convert a bunch of photos into a video with crossfade between them. The number of photos I am converting is variable
I am using the code from HERE to apply the crossfade :

    


    Since the number of photos are variable I looped over all the photos in the directory and generated the -loop and also the second part ([0:v]fade=t=out:st=4:d=1[v0] ;) :

    


    for i in range(os.listdir('photos')):
    if i == 0:
        text += f'\n-loop 1 -t 60 -i photos/Image{i+1}.jpg \\\n'
        text2 = '\n[0:v]fade=t=out:st=4:d=1[v0]; \\\n'
    else:
        text += f'-loop 1 -t 60 -i photos/Image{i+1}.jpg \\\n'
        text2 += f' [{i}:v]fade=t=in:st=0:d=1,fade=t=out:st=4:d=1[v{i}]; \\\n'

#And the Subprocess part  

command = f'ffmpeg \
    {text} \
    -filter-complex \
    {text2} -map "[v]" video/out.mp4'
p = subprocess.call(command, shell=True) 


    


    But this thing didn't create any video but said this :

    


    Use -h to get full help or, even better, run 'man ffmpeg'


    


    The full output :

    


    ffmpeg version git-2019-11-11-20c5f4d Copyright (c) 2000-2019 the FFmpeg developers
  built with gcc 9.2.1 (GCC) 20191010
  configuration: --enable-gpl --enable-version3 --enable-sdl2 --enable-fontconfig --enable-gnutls --enable-iconv --enable-libass --enable-libdav1d --enable-libbluray --enable-libfreetype --enable-libmp3lame --enable-libopencore-amrnb --enable-libopencore-amrwb --enable-libopenjpeg --enable-libopus --enable-libshine --enable-libsnappy --enable-libsoxr --enable-libtheora --enable-libtwolame --enable-libvpx --enable-libwavpack --enable-libwebp --enable-libx264 --enable-libx265 --enable-libxml2 --enable-libzimg --enable-lzma --enable-zlib --enable-gmp --enable-libvidstab --enable-libvorbis --enable-libvo-amrwbenc --enable-libmysofa --enable-libspeex --enable-libxvid --enable-libaom --enable-libmfx --enable-ffnvcodec --enable-cuvid --enable-d3d11va --enable-nvenc --enable-nvdec --enable-dxva2 --enable-avisynth --enable-libopenmpt --enable-amf
  libavutil      56. 35.101 / 56. 35.101
  libavcodec     58. 61.100 / 58. 61.100
  libavformat    58. 34.101 / 58. 34.101
  libavdevice    58.  9.100 / 58.  9.100
  libavfilter     7. 66.100 /  7. 66.100
  libswscale      5.  6.100 /  5.  6.100
  libswresample   3.  6.100 /  3.  6.100
  libpostproc    55.  6.100 / 55.  6.100
Hyper fast Audio and Video encoder
usage: ffmpeg [options] [[infile options] -i infile]... {[outfile options] outfile}...

Use -h to get full help or, even better, run 'man ffmpeg'


    


  • How to Read DJI FPV Feed as OpenCV Object ?

    24 mai 2019, par Walter Morawa

    I’ve officially spent a lot of time looking for a solution to reading DJI’s FPV feed as an OpenCV Mat object. I am probably overlooking something simple, since I am not too familiar with Image Encoding/Decoding.

    I apologize if I am missing something very basic, but I know I’m not the first person to have issues getting DJI’s FPV feed, and answering this question, especially if option 1 is possible, would be extremely valuable to many developers. Please consider upvoting this question, as I’ve thoroughly researched this issue and future developers who come across it will likely run into a bunch of the same issues I had.

    I’m willing to use ffmpeg or Javacv if necessary, but that’s quite the hurdle for most Android developers as we’re going to have to use cpp, ndk, terminal for testing, etc. That seems like overkill.

    I believe the issue lies in the fact that we need to decode both the byte array of length 6 (info array) and the byte array with current frame info simultaneously. Thanks in advance for your time.

    Basically, DJI’s FPV feed comes in a number of formats.

    1. Raw H264 (MPEG4) in VideoFeeder.VideoDataListener
        // The callback for receiving the raw H264 video data for camera live view
    
    mReceivedVideoDataListener = new VideoFeeder.VideoDataListener() {
    
        @Override
    
        public void onReceive(byte[] videoBuffer, int size) {
    
            //Log.d("BytesReceived", Integer.toString(videoStreamFrameNumber));
    
            if (videoStreamFrameNumber++%30 == 0){
    
                //convert video buffer to opencv array
    
                OpenCvAndModelAsync openCvAndModelAsync = new OpenCvAndModelAsync();
    
                openCvAndModelAsync.execute(videoBuffer);
    
            }
    
            if (mCodecManager != null) {
    
                mCodecManager.sendDataToDecoder(videoBuffer, size);
    
            }
    
        }
    
    };
    1. DJI also has it’s own Android decoder sample with FFMPEG to convert to YUV format.
        @Override
    
    public void onYuvDataReceived(final ByteBuffer yuvFrame, int dataSize, final int width, final int height) {
    
        //In this demo, we test the YUV data by saving it into JPG files.
    
        //DJILog.d(TAG, "onYuvDataReceived " + dataSize);
    
        if (count++ % 30 == 0 && yuvFrame != null) {
    
            final byte[] bytes = new byte[dataSize];
    
            yuvFrame.get(bytes);
    
            AsyncTask.execute(new Runnable() {
    
                @Override
    
                public void run() {
    
                    if (bytes.length >= width * height) {
    
                        Log.d("MatWidth", "Made it");
    
                        YuvImage yuvImage = saveYuvDataToJPEG(bytes, width, height);
    
                        Bitmap rgbYuvConvert = convertYuvImageToRgb(yuvImage, width, height);
    

    
                        Mat yuvMat = new Mat(height, width, CvType.CV_8UC1);
    
                        yuvMat.put(0, 0, bytes);
    
                        //OpenCv Stuff
    
                    }
    
                }
    
            });
    
        }
    
    }
    1. DJI also appears to have a "getRgbaData" function, but there is literally not a single example online or by DJI. Go ahead and Google "DJI getRgbaData"... There’s only the reference to the api documentation that explains the self explanatory parameters and return values but nothing else. I couldn’t figure out where to call this and there doesn’t appear to be a callback function as there is with YUV. You can’t call it from the h264b byte array directly, but perhaps you can get it from the yuv data.

    Option 1 is much more preferable to option 2, since YUV format has quality issues. Option 3 would also likely involve a decoder.

    Here’s a screenshot that DJI’s own YUV conversion produces. WalletPhoneYuv

    I’ve looked at a bunch of things about how to improve the YUV, remove green and yellow colors and whatnot, but at this point if DJI can’t do it right, I don’t want to invest resources there.

    Regarding Option 1, I know there’s FFMPEG and JavaCV that seem like good options if I have to go the video decoding route. However, both options seem quite time consuming. This JavaCV H264 conversion seems unnecessarily complex. I found it from this relevant question.

    Moreover, from what I understand, OpenCV can’t handle reading and writing video files without FFMPEG, but I’m not trying to read a video file, I am trying to read an H264/MPEG4 byte[] array. The following code seems to get positive results.

        /* Async OpenCV Code */
    
    private class OpenCvAndModelAsync extends AsyncTask {
    
        @Override
    
        protected double[] doInBackground(byte[]... params) {//Background Code Executing. Don't touch any UI components
    
            //get fpv feed and convert bytes to mat array
    
            Mat videoBufMat = new Mat(4, params[0].length, CvType.CV_8UC4);
    
            videoBufMat.put(0,0, params[0]);
    
            //if I add this in it says the bytes are empty.
    
            //Mat videoBufMat = Imgcodecs.imdecode(encodeVideoBuf, Imgcodecs.IMREAD_ANYCOLOR);
    
            //encodeVideoBuf.release();
    
            Log.d("MatRgba", videoBufMat.toString());
    
            for (int i = 0; i< videoBufMat.rows(); i++){
    
                for (int j=0; j< videoBufMat.cols(); j++){
    
                    double[] rgb = videoBufMat.get(i, j);
    
                    Log.i("Matrix", "red: "+rgb[0]+" green: "+rgb[1]+" blue: "+rgb[2]+" alpha: "
    
                            + rgb[3] + " Length: " + rgb.length + " Rows: "
    
                            + videoBufMat.rows() + " Columns: " + videoBufMat.cols());
    
                }
    
            }
    
            double[] center = openCVThingy(videoBufMat);
    
            return center;
    
        }
    
        protected void onPostExecute(double[] center) {
    
            //handle ui or another async task if necessary
    
        }
    
    }

    Rows = 4, Columns > 30k. I get lots of RGB values that seem valid, such as red = 113, green=75, blue=90, alpha=220 as a made up example ; however, I get a ton of 0,0,0,0 values. That should be somewhat okay, since Black is 0,0,0 (although I would have thought the alpha would be higher) and I have a black object in my image.

    However, when I try to compute the contours from this image, I almost always get that the moments (center x, y) are exactly in the center of the image. This error has nothing to do with my color filter or contours algorithm, as I wrote a script in python and tested that I implemented it correctly in Android by reading a still image and getting the exact same number of contours, position, etc in both Python and Android.

    I noticed it has something to do with the videoBuffer byte size (bonus points if you can explain why every other length is 6 !)

    2019-05-23 21:14:29.601 21431-22086/com.dji.simulatorDemo D/VideoBufferSize: 2425
    
2019-05-23 21:14:29.802 21431-22086/com.dji.simulatorDemo D/VideoBufferSize: 2659
    
2019-05-23 21:14:30.004 21431-22086/com.dji.simulatorDemo D/VideoBufferSize: 6
    
2019-05-23 21:14:30.263 21431-22086/com.dji.simulatorDemo D/VideoBufferSize: 6015
    
2019-05-23 21:14:30.507 21431-22086/com.dji.simulatorDemo D/VideoBufferSize: 6
    
2019-05-23 21:14:30.766 21431-22086/com.dji.simulatorDemo D/VideoBufferSize: 4682
    
2019-05-23 21:14:31.005 21431-22086/com.dji.simulatorDemo D/VideoBufferSize: 6
    
2019-05-23 21:14:31.234 21431-22086/com.dji.simulatorDemo D/VideoBufferSize: 2840
    
2019-05-23 21:14:31.433 21431-22086/com.dji.simulatorDemo D/VideoBufferSize: 4482
    
2019-05-23 21:14:31.664 21431-22086/com.dji.simulatorDemo D/VideoBufferSize: 6
    
2019-05-23 21:14:31.927 21431-22086/com.dji.simulatorDemo D/VideoBufferSize: 4768
    
2019-05-23 21:14:32.174 21431-22086/com.dji.simulatorDemo D/VideoBufferSize: 6
    
2019-05-23 21:14:32.433 21431-22086/com.dji.simulatorDemo D/VideoBufferSize: 4700
    
2019-05-23 21:14:32.668 21431-22086/com.dji.simulatorDemo D/VideoBufferSize: 6
    
2019-05-23 21:14:32.864 21431-22086/com.dji.simulatorDemo D/VideoBufferSize: 4740
    
2019-05-23 21:14:33.102 21431-22086/com.dji.simulatorDemo D/VideoBufferSize: 6
    
2019-05-23 21:14:33.365 21431-22086/com.dji.simulatorDemo D/VideoBufferSize: 4640

    My questions :

    I. Is this the correct format way to read an h264 byte as mat ?
    Assuming the format is RGBA, that means row = 4 and columns = byte[].length, and CvType.CV_8UC4. Do I have height and width correct ? Something tells me YUV height and width is off. I was getting some meaningful results, but the contours were exactly in the center, just like with the H264.

    II. Does OpenCV handle MP4 in android like this ? If not, do I need to use FFMPEG or JavaCV ?

    III. Does the int size have something to do with it ? Why is the int size occassionally 6, and other times 2400 to 6000 ? I’ve heard about the difference between this frames information and information about the next frame, but I’m simply not knowledgeable enough to know how to apply that here.
    I’m starting to think this is where the issue lies. Since I need to get the 6 byte array for info about next frame, perhaps my modulo 30 is incorrect. So should I pass the 29th or 31st frame as a format byte for each frame ? How is that done in opencv or are we doomed to use to the the complicated ffmpeg.

    IV. Can I fix this using Imcodecs ? I was hoping opencv would natively handle whether a frame was color from this frame or info about next frame. I added the below code, but I am getting an empty array :

    Mat videoBufMat = Imgcodecs.imdecode(new MatOfByte(params[0]), Imgcodecs.IMREAD_UNCHANGED);

    This also is empty :

    Mat encodeVideoBuf = new Mat(4, params[0].length, CvType.CV_8UC4);
    
encodeVideoBuf.put(0,0, params[0]);
    
Mat videoBufMat = Imgcodecs.imdecode(encodeVideoBuf, Imgcodecs.IMREAD_UNCHANGED);

    V. Should I try converting the bytes into Android jpeg and then import it ? Why is djis yuv decoder so complicated looking ? It makes me cautious from wanting to try ffmpeg or Javacv and just stick to Android decoder or opencv decoder.

    VI. At what stage should I resize the frames to speed up calculations ?

  • Are there differences between the parameters of different versions of ffmpeg ?

    13 octobre 2019, par Mauro Alejandro Pereira

    I want to obtain a different raw video for each frame of an MP4 file.
    My instruction works in an old version of ffmpeg but not in the new one.

    In the mp4 file there are 137 frames. It is checked. The versions are installed on different machines.

    Versions 2.8.15 :

    $ ffmpeg -i ./video.mp4 -vf fps=30 -vframes 137 -vcodec rawvideo -s '1920x1080' -pix_fmt gray -threads 0 frame%08d.raw
    
ffmpeg version 2.8.15-0ubuntu0.16.04.1 Copyright (c) 2000-2018 the FFmpeg developers
    
  built with gcc 5.4.0 (Ubuntu 5.4.0-6ubuntu1~16.04.10) 20160609
    
  configuration: --prefix=/usr --extra-version=0ubuntu0.16.04.1 --build-suffix=-ffmpeg --toolchain=hardened --libdir=/usr/lib/x86_64-linux-gnu --incdir=/usr/include/x86_64-linux-gnu --cc=cc --cxx=g++ --enable-gpl --enable-shared --disable-stripping --disable-decoder=libopenjpeg --disable-decoder=libschroedinger --enable-avresample --enable-avisynth --enable-gnutls --enable-ladspa --enable-libass --enable-libbluray --enable-libbs2b --enable-libcaca --enable-libcdio --enable-libflite --enable-libfontconfig --enable-libfreetype --enable-libfribidi --enable-libgme --enable-libgsm --enable-libmodplug --enable-libmp3lame --enable-libopenjpeg --enable-libopus --enable-libpulse --enable-librtmp --enable-libschroedinger --enable-libshine --enable-libsnappy --enable-libsoxr --enable-libspeex --enable-libssh --enable-libtheora --enable-libtwolame --enable-libvorbis --enable-libvpx --enable-libwavpack --enable-libwebp --enable-libx265 --enable-libxvid --enable-libzvbi --enable-openal --enable-opengl --enable-x11grab --enable-libdc1394 --enable-libiec61883 --enable-libzmq --enable-frei0r --enable-libx264 --enable-libopencv
    
  libavutil      54. 31.100 / 54. 31.100
    
  libavcodec     56. 60.100 / 56. 60.100
    
  libavformat    56. 40.101 / 56. 40.101
    
  libavdevice    56.  4.100 / 56.  4.100
    
  libavfilter     5. 40.101 /  5. 40.101
    
  libavresample   2.  1.  0 /  2.  1.  0
    
  libswscale      3.  1.101 /  3.  1.101
    
  libswresample   1.  2.101 /  1.  2.101
    
  libpostproc    53.  3.100 / 53.  3.100
    
Input #0, mov,mp4,m4a,3gp,3g2,mj2, from './video.mp4':
    
   Metadata:
    
    major_brand     : isom
    
    minor_version   : 512
    
    compatible_brands: mp41mp42
    
    creation_time   : 2019-03-11 16:16:54
    
  Duration: 00:00:04.57, start: 0.000000, bitrate: 14014 kb/s
    
    Stream #0:0(eng): Video: h264 (High) (avc1 / 0x31637661), yuv420p(tv, bt709), 1920x1080 [SAR 1:1 DAR 16:9], 13816 kb/s, 30 fps, 30 tbr, 30k tbn, 60 tbc (default)
    
    Metadata:
    
      creation_time   : 2019-03-11 16:16:54
    
      encoder         : AVC Coding
    
    Stream #0:1(eng): Audio: aac (LC) (mp4a / 0x6134706D), 48000 Hz, stereo, fltp, 192 kb/s (default)
    
    Metadata:
    
      creation_time   : 2019-03-11 16:16:54
    
Output #0, image2, to 'frame%08d.raw':
    
  Metadata:
    
    major_brand     : isom
    
    minor_version   : 512
    
    compatible_brands: mp41mp42
    
    encoder         : Lavf56.40.101
    
    Stream #0:0(eng): Video: rawvideo (Y800 / 0x30303859), gray, 1920x1080 [SAR 1:1 DAR 16:9], q=2-31, 200 kb/s, 30 fps, 30 tbn, 30 tbc (default)
    
    Metadata:
    
      creation_time   : 2019-03-11 16:16:54
    
      encoder         : Lavc56.60.100 rawvideo
    
Stream mapping:
    
  Stream #0:0 -> #0:0 (h264 (native) -> rawvideo (native))
    
Press [q] to stop, [?] for help
    
frame=  137 fps= 73 q=-0.0 Lsize=N/A time=00:00:04.56 bitrate=N/A dup=1 drop=0    
    
video:277425kB audio:0kB subtitle:0kB other streams:0kB global headers:0kB muxing overhead: unknown

    Version 4.1.4 :

    $ ffmpeg -i ./video.mp4 -vf fps=30 -vframes 137 -vcodec rawvideo -s '1920x1080' -pix_fmt gray -threads 0 frame%08d.raw
    
ffmpeg version 4.1.4-1~deb10u1 Copyright (c) 2000-2019 the FFmpeg developers
    
  built with gcc 8 (Debian 8.3.0-6)
    
  configuration: --prefix=/usr --extra-version='1~deb10u1' --toolchain=hardened --libdir=/usr/lib/x86_64-linux-gnu --incdir=/usr/include/x86_64-linux-gnu --arch=amd64 --enable-gpl --disable-stripping --enable-avresample --disable-filter=resample --enable-avisynth --enable-gnutls --enable-ladspa --enable-libaom --enable-libass --enable-libbluray --enable-libbs2b --enable-libcaca --enable-libcdio --enable-libcodec2 --enable-libflite --enable-libfontconfig --enable-libfreetype --enable-libfribidi --enable-libgme --enable-libgsm --enable-libjack --enable-libmp3lame --enable-libmysofa --enable-libopenjpeg --enable-libopenmpt --enable-libopus --enable-libpulse --enable-librsvg --enable-librubberband --enable-libshine --enable-libsnappy --enable-libsoxr --enable-libspeex --enable-libssh --enable-libtheora --enable-libtwolame --enable-libvidstab --enable-libvorbis --enable-libvpx --enable-libwavpack --enable-libwebp --enable-libx265 --enable-libxml2 --enable-libxvid --enable-libzmq --enable-libzvbi --enable-lv2 --enable-omx --enable-openal --enable-opengl --enable-sdl2 --enable-libdc1394 --enable-libdrm --enable-libiec61883 --enable-chromaprint --enable-frei0r --enable-libx264 --enable-shared
    
  libavutil      56. 22.100 / 56. 22.100
    
  libavcodec     58. 35.100 / 58. 35.100
    
  libavformat    58. 20.100 / 58. 20.100
    
  libavdevice    58.  5.100 / 58.  5.100
    
  libavfilter     7. 40.101 /  7. 40.101
    
  libavresample   4.  0.  0 /  4.  0.  0
    
  libswscale      5.  3.100 /  5.  3.100
    
  libswresample   3.  3.100 /  3.  3.100
    
  libpostproc    55.  3.100 / 55.  3.100
    
[mov,mp4,m4a,3gp,3g2,mj2 @ 0x558d1a5bb880] st: 0 edit list: 1 Missing key frame while searching for timestamp: 0
    
[mov,mp4,m4a,3gp,3g2,mj2 @ 0x558d1a5bb880] st: 0 edit list 1 Cannot find an index entry before timestamp: 0.
    
Input #0, mov,mp4,m4a,3gp,3g2,mj2, from './video.mp4':
    
  Metadata:
    
    major_brand     : isom
    
    minor_version   : 512
    
    compatible_brands: mp41mp42
    
    creation_time   : 2019-03-11T16:16:54.000000Z
    
  Duration: 00:00:04.57, start: 0.000000, bitrate: 14014 kb/s
    
    Stream #0:0(eng): Video: h264 (High) (avc1 / 0x31637661), yuv420p(tv, bt709), 1920x1080 [SAR 1:1 DAR 16:9], 13816 kb/s, 30 fps, 30 tbr, 30k tbn, 60 tbc (default)
    
    Metadata:
    
      creation_time   : 2019-03-11T16:16:54.000000Z
    
      encoder         : AVC Coding
    
    Stream #0:1(eng): Audio: aac (LC) (mp4a / 0x6134706D), 48000 Hz, stereo, fltp, 192 kb/s (default)
    
    Metadata:
    
      creation_time   : 2019-03-11T16:16:54.000000Z
    
Stream mapping:
    
  Stream #0:0 -> #0:0 (h264 (native) -> rawvideo (native))
    
Press [q] to stop, [?] for help
    
Output #0, image2, to 'frame%08d.raw':
    
  Metadata:
    
    major_brand     : isom
    
    minor_version   : 512
    
    compatible_brands: mp41mp42
    
    encoder         : Lavf58.20.100
    
    Stream #0:0(eng): Video: rawvideo (Y800 / 0x30303859), gray,     1920x1080 [SAR 1:1 DAR 16:9], q=2-31, 497664 kb/s, 30 fps, 30 tbn, 30 tbc (default)
    
    Metadata:
    
      creation_time   : 2019-03-11T16:16:54.000000Z
    
      encoder         : Lavc58.35.100 rawvideo
    
frame=  136 fps= 25 q=-0.0 Lsize=N/A time=00:00:04.53 bitrate=N/A speed=0.834x    
    
video:275400kB audio:0kB subtitle:0kB other streams:0kB global headers:0kB muxing overhead: unknown

    In the latest version, I expect 137 files but the amount is 136.

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