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  • Utilisation et configuration du script

    19 janvier 2011, par

    Informations spécifiques à la distribution Debian
    Si vous utilisez cette distribution, vous devrez activer les dépôts "debian-multimedia" comme expliqué ici :
    Depuis la version 0.3.1 du script, le dépôt peut être automatiquement activé à la suite d’une question.
    Récupération du script
    Le script d’installation peut être récupéré de deux manières différentes.
    Via svn en utilisant la commande pour récupérer le code source à jour :
    svn co (...)

  • Encoding and processing into web-friendly formats

    13 avril 2011, par

    MediaSPIP automatically converts uploaded files to internet-compatible formats.
    Video files are encoded in MP4, Ogv and WebM (supported by HTML5) and MP4 (supported by Flash).
    Audio files are encoded in MP3 and Ogg (supported by HTML5) and MP3 (supported by Flash).
    Where possible, text is analyzed in order to retrieve the data needed for search engine detection, and then exported as a series of image files.
    All uploaded files are stored online in their original format, so you can (...)

  • List of compatible distributions

    26 avril 2011, par

    The table below is the list of Linux distributions compatible with the automated installation script of MediaSPIP. Distribution nameVersion nameVersion number Debian Squeeze 6.x.x Debian Weezy 7.x.x Debian Jessie 8.x.x Ubuntu The Precise Pangolin 12.04 LTS Ubuntu The Trusty Tahr 14.04
    If you want to help us improve this list, you can provide us access to a machine whose distribution is not mentioned above or send the necessary fixes to add (...)

Sur d’autres sites (5660)

  • FFMPEG on android giving corrupted MP4 from captured photos.

    5 août 2015, par qstra

    im using this project :
    https://github.com/hiteshsondhi88/ffmpeg-android-java

    To convert set of images (1img.jpg, 2img.jpg etc.) to mp4 movie, from my test folder to emulated/0/

    I have app that taking pics every X seconds to that test folder, the output file has always sobie MBs so it isnt empty, tell my what part of code You want or what files i have to give You.

    Im beeging for help ! :)

    This is my command :

       public void onClick(View v) {
       switch (v.getId()) {
           case R.id.run_command:


               String cmd = "-y -framerate 1 -i /sdcard/test/%dimg.jpg /sdcard/a.mp4";

              // String cmd = commandEditText.getText().toString();
               String[] command = cmd.split(" ");
               if (command.length != 0) {
                   execFFmpegBinary(command);
               } else {
                   Toast.makeText(Home.this, getString(R.string.empty_command_toast), Toast.LENGTH_LONG).show();
               }
               break;
       }
    }

    I want to add, that if im get some images from google its working, but not working on capptured photos from phone.

  • Decode mp3 using FFMpeg, Android NDK - What is wrong with my AVFormatContext ?

    27 février 2020, par michpohl

    I am trying to decode am MP3 file to a raw PCM stream using FFMpeg via JNI on Android. I have compiled the latest FFMpeg version (4.2) and added it to my app. This did not make any problems.
    The goal is to be able to use mp3 files from the device’s storage for playback with oboe

    Since I am relatively inexperienced with both C++ and FFMpeg, my approach is based upon this :
    oboe’s RhythmGame example

    I have based my FFMpegExtractorclass on the one found in the example here. With the help of StackOverflow the AAssetManageruse was removed and instead a MediaSource helper class now serves as a wrapper for my stream (see here)

    But unfortunately, creating the AVFormatContext doesn’t work right - and I can’t seem to understand why. Since I have very limited understanding of correct pointer usage and C++ memory management, I suspect it’s most likely I’m doing something wrong in that area. But honestly, I have no idea.

    This is my FFMpegExtractor.h :

    #define MYAPP_FFMPEGEXTRACTOR_H

    extern "C" {
    #include <libavformat></libavformat>avformat.h>
    #include <libswresample></libswresample>swresample.h>
    #include <libavutil></libavutil>opt.h>
    }

    #include <cstdint>
    #include <android></android>asset_manager.h>
    #include
    #include <fstream>
    #include "MediaSource.cpp"


    class FFMpegExtractor {
    public:

       FFMpegExtractor();

       ~FFMpegExtractor();

       int64_t decode2(char *filepath, uint8_t *targetData, AudioProperties targetProperties);

    private:
       MediaSource *mSource;

       bool createAVFormatContext(AVIOContext *avioContext, AVFormatContext **avFormatContext);

       bool openAVFormatContext(AVFormatContext *avFormatContext);

       int32_t cleanup(AVIOContext *avioContext, AVFormatContext *avFormatContext);

       bool getStreamInfo(AVFormatContext *avFormatContext);

       AVStream *getBestAudioStream(AVFormatContext *avFormatContext);

       AVCodec *findCodec(AVCodecID id);

       void printCodecParameters(AVCodecParameters *params);

       bool createAVIOContext2(const std::string &amp;filePath, uint8_t *buffer, uint32_t bufferSize,
                               AVIOContext **avioContext);
    };


    #endif //MYAPP_FFMPEGEXTRACTOR_H
    </fstream></cstdint>

    This is FFMPegExtractor.cpp :

    #include <memory>
    #include <oboe></oboe>Definitions.h>
    #include "FFMpegExtractor.h"
    #include "logging.h"
    #include <fstream>

    FFMpegExtractor::FFMpegExtractor() {
       mSource = new MediaSource;
    }

    FFMpegExtractor::~FFMpegExtractor() {
       delete mSource;
    }

    constexpr int kInternalBufferSize = 1152; // Use MP3 block size. https://wiki.hydrogenaud.io/index.php?title=MP3

    /**
    * Reads from an IStream into FFmpeg.
    *
    * @param ptr       A pointer to the user-defined IO data structure.
    * @param buf       A buffer to read into.
    * @param buf_size  The size of the buffer buff.
    *
    * @return The number of bytes read into the buffer.
    */


    // If FFmpeg needs to read the file, it will call this function.
    // We need to fill the buffer with file's data.
    int read(void *opaque, uint8_t *buffer, int buf_size) {
       MediaSource *source = (MediaSource *) opaque;
       return source->read(buffer, buf_size);
    }

    // If FFmpeg needs to seek in the file, it will call this function.
    // We need to change the read pos.
    int64_t seek(void *opaque, int64_t offset, int whence) {
       MediaSource *source = (MediaSource *) opaque;
       return source->seek(offset, whence);
    }


    // Create and save a MediaSource instance.
    bool FFMpegExtractor::createAVIOContext2(const std::string &amp;filepath, uint8_t *buffer, uint32_t bufferSize,
                                            AVIOContext **avioContext) {

       mSource = new MediaSource;
       mSource->open(filepath);
       constexpr int isBufferWriteable = 0;

       *avioContext = avio_alloc_context(
               buffer, // internal buffer for FFmpeg to use
               bufferSize, // For optimal decoding speed this should be the protocol block size
               isBufferWriteable,
               mSource, // Will be passed to our callback functions as a (void *)
               read, // Read callback function
               nullptr, // Write callback function (not used)
               seek); // Seek callback function

       if (*avioContext == nullptr) {
           LOGE("Failed to create AVIO context");
           return false;
       } else {
           return true;
       }
    }

    bool
    FFMpegExtractor::createAVFormatContext(AVIOContext *avioContext,
                                          AVFormatContext **avFormatContext) {

       *avFormatContext = avformat_alloc_context();
       (*avFormatContext)->pb = avioContext;

       if (*avFormatContext == nullptr) {
           LOGE("Failed to create AVFormatContext");
           return false;
       } else {
           LOGD("Successfully created AVFormatContext");
           return true;
       }
    }

    bool FFMpegExtractor::openAVFormatContext(AVFormatContext *avFormatContext) {

       int result = avformat_open_input(&amp;avFormatContext,
                                        "", /* URL is left empty because we're providing our own I/O */
                                        nullptr /* AVInputFormat *fmt */,
                                        nullptr /* AVDictionary **options */
       );

       if (result == 0) {
           return true;
       } else {
           LOGE("Failed to open file. Error code %s", av_err2str(result));
           return false;
       }
    }

    bool FFMpegExtractor::getStreamInfo(AVFormatContext *avFormatContext) {

       int result = avformat_find_stream_info(avFormatContext, nullptr);
       if (result == 0) {
           return true;
       } else {
           LOGE("Failed to find stream info. Error code %s", av_err2str(result));
           return false;
       }
    }

    AVStream *FFMpegExtractor::getBestAudioStream(AVFormatContext *avFormatContext) {

       int streamIndex = av_find_best_stream(avFormatContext, AVMEDIA_TYPE_AUDIO, -1, -1, nullptr, 0);

       if (streamIndex &lt; 0) {
           LOGE("Could not find stream");
           return nullptr;
       } else {
           return avFormatContext->streams[streamIndex];
       }
    }

    int64_t FFMpegExtractor::decode2(
           char* filepath,
           uint8_t *targetData,
           AudioProperties targetProperties) {

       LOGD("Decode SETUP");
       int returnValue = -1; // -1 indicates error

       // Create a buffer for FFmpeg to use for decoding (freed in the custom deleter below)
       auto buffer = reinterpret_cast(av_malloc(kInternalBufferSize));


       // Create an AVIOContext with a custom deleter
       std::unique_ptr ioContext{
               nullptr,
               [](AVIOContext *c) {
                   av_free(c->buffer);
                   avio_context_free(&amp;c);
               }
       };
       {
           AVIOContext *tmp = nullptr;
           if (!createAVIOContext2(filepath, buffer, kInternalBufferSize, &amp;tmp)) {
               LOGE("Could not create an AVIOContext");
               return returnValue;
           }
           ioContext.reset(tmp);
       }
       // Create an AVFormatContext using the avformat_free_context as the deleter function
       std::unique_ptr formatContext{
               nullptr,
               &amp;avformat_free_context
       };

       {
           AVFormatContext *tmp;
           if (!createAVFormatContext(ioContext.get(), &amp;tmp)) return returnValue;
           formatContext.reset(tmp);
       }
       if (!openAVFormatContext(formatContext.get())) return returnValue;
       LOGD("172");

       if (!getStreamInfo(formatContext.get())) return returnValue;
       LOGD("175");

       // Obtain the best audio stream to decode
       AVStream *stream = getBestAudioStream(formatContext.get());
       if (stream == nullptr || stream->codecpar == nullptr) {
           LOGE("Could not find a suitable audio stream to decode");
           return returnValue;
       }
       LOGD("183");

       printCodecParameters(stream->codecpar);

       // Find the codec to decode this stream
       AVCodec *codec = avcodec_find_decoder(stream->codecpar->codec_id);
       if (!codec) {
           LOGE("Could not find codec with ID: %d", stream->codecpar->codec_id);
           return returnValue;
       }

       // Create the codec context, specifying the deleter function
       std::unique_ptr codecContext{
               nullptr,
               [](AVCodecContext *c) { avcodec_free_context(&amp;c); }
       };
       {
           AVCodecContext *tmp = avcodec_alloc_context3(codec);
           if (!tmp) {
               LOGE("Failed to allocate codec context");
               return returnValue;
           }
           codecContext.reset(tmp);
       }

       // Copy the codec parameters into the context
       if (avcodec_parameters_to_context(codecContext.get(), stream->codecpar) &lt; 0) {
           LOGE("Failed to copy codec parameters to codec context");
           return returnValue;
       }

       // Open the codec
       if (avcodec_open2(codecContext.get(), codec, nullptr) &lt; 0) {
           LOGE("Could not open codec");
           return returnValue;
       }

       // prepare resampler
       int32_t outChannelLayout = (1 &lt;&lt; targetProperties.channelCount) - 1;
       LOGD("Channel layout %d", outChannelLayout);

       SwrContext *swr = swr_alloc();
       av_opt_set_int(swr, "in_channel_count", stream->codecpar->channels, 0);
       av_opt_set_int(swr, "out_channel_count", targetProperties.channelCount, 0);
       av_opt_set_int(swr, "in_channel_layout", stream->codecpar->channel_layout, 0);
       av_opt_set_int(swr, "out_channel_layout", outChannelLayout, 0);
       av_opt_set_int(swr, "in_sample_rate", stream->codecpar->sample_rate, 0);
       av_opt_set_int(swr, "out_sample_rate", targetProperties.sampleRate, 0);
       av_opt_set_int(swr, "in_sample_fmt", stream->codecpar->format, 0);
       av_opt_set_sample_fmt(swr, "out_sample_fmt", AV_SAMPLE_FMT_FLT, 0);
       av_opt_set_int(swr, "force_resampling", 1, 0);

       // Check that resampler has been inited
       int result = swr_init(swr);
       if (result != 0) {
           LOGE("swr_init failed. Error: %s", av_err2str(result));
           return returnValue;
       };
       if (!swr_is_initialized(swr)) {
           LOGE("swr_is_initialized is false\n");
           return returnValue;
       }

       // Prepare to read data
       int bytesWritten = 0;
       AVPacket avPacket; // Stores compressed audio data
       av_init_packet(&amp;avPacket);
       AVFrame *decodedFrame = av_frame_alloc(); // Stores raw audio data
       int bytesPerSample = av_get_bytes_per_sample((AVSampleFormat) stream->codecpar->format);

       LOGD("Bytes per sample %d", bytesPerSample);

       // While there is more data to read, read it into the avPacket
       while (av_read_frame(formatContext.get(), &amp;avPacket) == 0) {

           if (avPacket.stream_index == stream->index) {

               while (avPacket.size > 0) {
                   // Pass our compressed data into the codec
                   result = avcodec_send_packet(codecContext.get(), &amp;avPacket);
                   if (result != 0) {
                       LOGE("avcodec_send_packet error: %s", av_err2str(result));
                       goto cleanup;
                   }

                   // Retrieve our raw data from the codec
                   result = avcodec_receive_frame(codecContext.get(), decodedFrame);
                   if (result != 0) {
                       LOGE("avcodec_receive_frame error: %s", av_err2str(result));
                       goto cleanup;
                   }

                   // DO RESAMPLING
                   auto dst_nb_samples = (int32_t) av_rescale_rnd(
                           swr_get_delay(swr, decodedFrame->sample_rate) + decodedFrame->nb_samples,
                           targetProperties.sampleRate,
                           decodedFrame->sample_rate,
                           AV_ROUND_UP);

                   short *buffer1;
                   av_samples_alloc(
                           (uint8_t **) &amp;buffer1,
                           nullptr,
                           targetProperties.channelCount,
                           dst_nb_samples,
                           AV_SAMPLE_FMT_FLT,
                           0);
                   int frame_count = swr_convert(
                           swr,
                           (uint8_t **) &amp;buffer1,
                           dst_nb_samples,
                           (const uint8_t **) decodedFrame->data,
                           decodedFrame->nb_samples);

                   int64_t bytesToWrite = frame_count * sizeof(float) * targetProperties.channelCount;
                   memcpy(targetData + bytesWritten, buffer1, (size_t) bytesToWrite);
                   bytesWritten += bytesToWrite;
                   av_freep(&amp;buffer1);

                   avPacket.size = 0;
                   avPacket.data = nullptr;
               }
           }
       }

       av_frame_free(&amp;decodedFrame);

       returnValue = bytesWritten;

       cleanup:
       return returnValue;
    }

    void FFMpegExtractor::printCodecParameters(AVCodecParameters *params) {

       LOGD("Stream properties");
       LOGD("Channels: %d", params->channels);
       LOGD("Channel layout: %"
                    PRId64, params->channel_layout);
       LOGD("Sample rate: %d", params->sample_rate);
       LOGD("Format: %s", av_get_sample_fmt_name((AVSampleFormat) params->format));
       LOGD("Frame size: %d", params->frame_size);
    }
    </fstream></memory>

    And this is the MediaSource.cpp :

    #ifndef MYAPP_MEDIASOURCE_CPP
    #define MYAPP_MEDIASOURCE_CPP

    extern "C" {
    #include <libavformat></libavformat>avformat.h>
    #include <libswresample></libswresample>swresample.h>
    #include <libavutil></libavutil>opt.h>
    }

    #include <cstdint>
    #include <android></android>asset_manager.h>
    #include
    #include <fstream>
    #include "logging.h"

    // wrapper class for file stream
    class MediaSource {
    public:

       MediaSource() {
       }

       ~MediaSource() {
           source.close();
       }

       void open(const std::string &amp;filePath) {
           const char *x = filePath.c_str();
           LOGD("Opened %s", x);
           source.open(filePath, std::ios::in | std::ios::binary);
       }

       int read(uint8_t *buffer, int buf_size) {
           // read data to buffer
           source.read((char *) buffer, buf_size);
           // return how many bytes were read
           return source.gcount();
       }

       int64_t seek(int64_t offset, int whence) {
           if (whence == AVSEEK_SIZE) {
               // FFmpeg needs file size.
               int oldPos = source.tellg();
               source.seekg(0, std::ios::end);
               int64_t length = source.tellg();
               // seek to old pos
               source.seekg(oldPos);
               return length;
           } else if (whence == SEEK_SET) {
               // set pos to offset
               source.seekg(offset);
           } else if (whence == SEEK_CUR) {
               // add offset to pos
               source.seekg(offset, std::ios::cur);
           } else {
               // do not support other flags, return -1
               return -1;
           }
           // return current pos
           return source.tellg();
       }

    private:
       std::ifstream source;
    };

    #endif //MYAPP_MEDIASOURCE_CPP
    </fstream></cstdint>

    When the code is executed, I can see that I submit the correct file path, so I assume the resource mp3 is there.
    When this code is executed the app crashes in line 103 of FFMpegExtractor.cpp, at formatContext.reset(tmp);

    This is what Android Studio logs when the app crashes :

    --------- beginning of crash
    2020-02-27 14:31:26.341 9852-9945/com.user.myapp A/libc: Fatal signal 11 (SIGSEGV), code 1 (SEGV_MAPERR), fault addr 0x7fffffff0 in tid 9945 (chaelpohl.loopy), pid 9852 (user.myapp)

    This is the (sadly very short) output I get with ndk-stack :

    ********** Crash dump: **********
    Build fingerprint: 'samsung/dreamltexx/dreamlte:9/PPR1.180610.011/G950FXXU6DSK9:user/release-keys'
    #00 0x0000000000016c50 /data/app/com.user.myapp-D7dBCgHF-vdQNNSald4lWA==/lib/arm64/libavformat.so (avformat_free_context+260)
                                                                                                            avformat_free_context
                                                                                                            ??:0:0
    Crash dump is completed

    I tested a bit around, and every call to my formatContext crashes the app. So I assume there is something wrong with the input I provide to build it but I have no clue how to debug this.

    Any help is appreciated ! (Happy to provide additional resources if something crucial is missing).

  • Real-time streaming of rawdata images to Android with FFMPEG

    29 juillet 2015, par Philies

    CONDITIONS

    I have an C++ server (Linux) and want to transmit rawdata images (RGB, 32bit) to an Android device in real-time.
    The server generates the rawdata images (with or without bitmap header) continuously every x miliseconds. Now, I want to put the rawdata images into a stream and transmit them without much delay to the Android client.

    I’ve chosen FFMPEG for this kind of job.

    The input for FFMPEG should be the rawdata images, which are generated just in time. The output should be an rtsp stream (h264 or is another format better ?).
    On client side I will play the stream with the Android MediaPlayer. That works for a RTSP url like rtsp ://184.72.239.149/vod/mp4:BigBuckBunny_115k.mov


    PREVIOUS APPROCH :

    I’ve installed FFMPEG on my server.

    Depending on this question : https://ffmpeg.org/pipermail/ffmpeg-user/2013-April/014617.html ... here is my FFMEG command :

    ffmpeg -an -f rawvideo -vcodec rawvideo -pix_fmt rgb32 -r 10 -i -vcodec libx264 -r 30 -tune zerolatency -preset ultrafast -bsf:v h264_mp4toannexb -f mpegts udp://192.168.1.20:1234

    Explanation of the parameters :

    • -an = ignore audio
    • -report = log file in current directory

    INPUT :

    • -f = rawvideo (video format)
    • -vcodec = rawvideo (video codec)
    • -pix_fmt = rgb32
    • -r = 10 (frame rate)

    OUTPUT :

    • -vcodec = libx264
    • -r = 30 (frame rate)
    • -bsf:v = h264_mp4toannexb
    • -f = mpegts udp ://192.168.1.20:1234

    C++ Server Code Snippet :

    /* -------  Get image rawdata from source ------- */
    ...
    /* -------  Create image header which fits to the image rawdata ------- */
    ...

    /* ------- Store the picture local (not necessary?) ------- */
    FILE *f;
    f = fopen("/home/philies/test.bmp","wb");

    //Write Bitmap Headers
    fwrite(&amp;imageFileHeader,1,sizeof(imageFileHeader),f);
    fwrite(imageInfoHeader,1, imageInfoHeader,f);

    //Write Bitmap Rawdata
    fwrite(lastImage.GetBitmapRawData(),1,imageSize,f);


    —> ffmpeg ???

    PROBLEMS/QUESTIONS :

    1. How can I specify the rawvideo of the ffmpeg command respectively how can I specify my bitmap rawdata (with or without header ?) as the input of the FFMPEG ?

    2. Is the FFMPEG command correct ?

    If I fire the FFMPEG command in the terminal I get this error :

    vcodec : no such file or directory

    EDIT :
    In the first step, I will open the udp stream with the VLC player on my Android device. After that I will set up a FFserver to create a RTSP stream