Recherche avancée

Sur d’autres sites (7597)

• ffmpeg how to do the "earrape" sound effect

  20 avril 2020, par Shalin Shah

  I was wondering how to do the earrape effect using ffmpeg where the audio just sounds completely destroyed. Here's an example :
https://www.youtube.com/watch?v=KiCmvQiAC8Q

  



  I've tried a bunch of combinations of different commands on ffmpeg and the closest I've gotten is the following (where I use the superequalizer and then make the volume super high) :

  



  import ffmpeg
(
    ffmpeg
    .input('shark.wav')
    .filter("superequalizer", 20, 20, 20, 20, 20, 20, 20, 20, 20, 20, 20, 20, 20, 20, 20, 20, 20, 20)
    .filter("volume", 10)
    .output('output_earrape.wav')
    .run()
)


  



  I'm using a python wrapper but here's the command line equivalent :

  



  ffmpeg -i shark.wav -af "superequalizer=1b=20:2b=20:3b=20:4b=20:5b=20:6b=20:7b=20:8b=20:9b=20:10b=20:11b=20:12b=20:13b=20:14b=20:15b=20:16b=20:17b=20:18b=20,volume=10" output_earrape.wav


  



  The problem with the above is that it doesn't do anything for files that aren't already super loud (such as recorded audio) and most of the time the audio actually just ends up clipping and then being super soft.

  



  Does anyone have suggestions on how to do this effect ? Thanks !

  


• Java sound vs C sound api in sound result

  18 août 2019, par Ahmed

  i finish developing a conference chat app using java, and i used mp3 as encoder and javacv ( ffmpeg ) as a library, but the sound i get not sonorous like Paltalk app

  i used java sound api to capture the sound then store the sound in a buffer , send it to the encoder and get the compressed bytes and send it via socket then decode it and play it in speaker.
  the sound format was like 44100 sample rate when i capture the sound in java and in encoder it generate 11025 sound.
  here how i get sound from java api

   AudioFormat format = new AudioFormat(44100.0f, 16 , 1, true, false);        
  
   // target dataline  (Mic)
  
  DataLine.Info info = new DataLine.Info(TargetDataLine.class, format);
  
  targetDataLine = (TargetDataLine) AudioSystem.getLine(info);
  
  targetDataLine.open();

  i want to know what the thing making sound sonorous ?

• How to capture sound from microphone with FFmpeg and then stream it in C/C++ ?

  9 octobre 2019, par Emad Kebriaei

  I’m trying to implementing the following line in C++ :

  fmpeg -ac 1 -f alsa -i hw:0,0 -acodec mp2 -ab 32k -ac 1 -re -f rtp rtp://localhost:1234

  The abovementioned line capture audio from the mic device and after some processing, stream it in RTP packet over UDP.
  I tried available resources but could not find such (or similar) implementation in C++.
  This is my code : (It was first developed by Lei Xiaouha to stream .flv file over RTMP. I changed in a way to capture audio from the microphone and store it in receive.mp2.)

  int main(int argc, char* argv[])
  
  {
  
      avdevice_register_all();
  
      av_register_all();
  
      //Network
  
      avformat_network_init();
  
  
  
      AVOutputFormat *ofmt = NULL;
  
      //Input AVFormatContext and Output AVFormatContext
  
      AVFormatContext *ifmt_ctx = NULL, *ofmt_ctx = NULL;
  
      AVPacket pkt;
  
      const char *in_filename, *out_filename;
  
      int ret, i;
  
      int videoindex=-1;
  
      int frame_index=0;
  
      AVInputFormat *fmt = nullptr;
  
  
  
      out_filename = "./receive.mp2";
  
      fmt = av_find_input_format("alsa");
  
      in_filename = "hw:0,0";
  
      int cnt=0;
  
      //Input
  
      if ((ret = avformat_open_input(&ifmt_ctx, in_filename, fmt, nullptr)) < 0) {
  
          printf( "Could not open input file.");
  
          goto end;
  
      }
  
      if ((ret = avformat_find_stream_info(ifmt_ctx, nullptr)) < 0) {
  
          printf( "Failed to retrieve input stream information");
  
          goto end;
  
      }
  
  
  
      for(i=0; inb_streams; i++)
  
          if(ifmt_ctx->streams[i]->codecpar->codec_type==AVMEDIA_TYPE_VIDEO){
  
              videoindex=i;
  
              break;
  
          }
  
  
  
      av_dump_format(ifmt_ctx, 0, in_filename, 0);
  
  
  
      //Output
  
      avformat_alloc_output_context2(&ofmt_ctx, nullptr, "mp2", out_filename); //
  
  
  
      if (!ofmt_ctx) {
  
          printf( "Could not create output context\n");
  
          ret = AVERROR_UNKNOWN;
  
          goto end;
  
      }
  
      ofmt = ofmt_ctx->oformat;
  
      for (i = 0; i < ifmt_ctx->nb_streams; i++) {
  
          //Create output AVStream according to input AVStream
  
          AVStream *in_stream = ifmt_ctx->streams[i];
  
          AVStream *out_stream = avformat_new_stream(ofmt_ctx, in_stream->codec->codec);
  
          if (!out_stream) {
  
              printf( "Failed allocating output stream\n");
  
              ret = AVERROR_UNKNOWN;
  
              goto end;
  
          }
  
          //Copy the settings of AVCodecContext
  
          ret = avcodec_copy_context(out_stream->codec, in_stream->codec);
  
          if (ret < 0) {
  
              printf( "Failed to copy context from input to output stream codec context\n");
  
              goto end;
  
          }
  
          out_stream->codec->codec_tag = 0;
  
          if (ofmt_ctx->oformat->flags & AVFMT_GLOBALHEADER)
  
              out_stream->codec->flags |= CODEC_FLAG_GLOBAL_HEADER;
  
      }
  
      //Dump Format------------------
  
      av_dump_format(ofmt_ctx, 0, out_filename, 1);
  
      //Open output URL
  
      if (!(ofmt->flags & AVFMT_NOFILE)) {
  
          ret = avio_open(&ofmt_ctx->pb, out_filename, AVIO_FLAG_WRITE);
  
          if (ret < 0) {
  
              printf( "Could not open output URL '%s'", out_filename);
  
              goto end;
  
          }
  
      }
  
      //Write file header
  
      ret = avformat_write_header(ofmt_ctx, nullptr);
  
      if (ret < 0) {
  
          printf( "Error occurred when opening output URL\n");
  
          goto end;
  
      }
  
  
  
  #if USE_H264BSF
  
      AVBitStreamFilterContext* h264bsfc =  av_bitstream_filter_init("h264_mp4toannexb");
  
  #endif
  
  
  
      while (1) {
  
          cnt++;
  
          AVStream *in_stream, *out_stream;
  
          //Get an AVPacket
  
          ret = av_read_frame(ifmt_ctx, &pkt);
  
          if (ret < 0)
  
              break;
  
  
  
          in_stream  = ifmt_ctx->streams[pkt.stream_index];
  
          out_stream = ofmt_ctx->streams[pkt.stream_index];
  
          /* copy packet */
  
          //Convert PTS/DTS
  
          pkt.pts = av_rescale_q_rnd(pkt.pts, in_stream->time_base, out_stream->time_base, (AVRounding)(AV_ROUND_NEAR_INF|AV_ROUND_PASS_MINMAX));
  
          pkt.dts = av_rescale_q_rnd(pkt.dts, in_stream->time_base, out_stream->time_base, (AVRounding)(AV_ROUND_NEAR_INF|AV_ROUND_PASS_MINMAX));
  
          pkt.duration = av_rescale_q(pkt.duration, in_stream->time_base, out_stream->time_base);
  
          pkt.pos = -1;
  
          //Print to Screen
  
          if(pkt.stream_index==videoindex){
  
              printf("Receive %8d video frames from input URL\n",frame_index);
  
              frame_index++;
  
  
  
  #if USE_H264BSF
  
              av_bitstream_filter_filter(h264bsfc, in_stream->codec, NULL, &pkt.data, &pkt.size, pkt.data, pkt.size, 0);
  
  #endif
  
          }
  
          ret = av_write_frame(ofmt_ctx, &pkt);
  
  //        ret = av_interleaved_write_frame(ofmt_ctx, &pkt);
  
  
  
          if (ret < 0) {
  
              printf( "Error muxing packet\n");
  
              break;
  
          }
  
  
  
          av_free_packet(&pkt);
  
      if (cnt > 1000)
  
          break;
  
      }
  
  
  
  #if USE_H264BSF
  
      av_bitstream_filter_close(h264bsfc);
  
  #endif
  
  
  
      //Write file trailer
  
      printf("suse");
  
      av_write_trailer(ofmt_ctx);
  
  end:
  
      avformat_close_input(&ifmt_ctx);
  
      /* close output */
  
      if (ofmt_ctx && !(ofmt->flags & AVFMT_NOFILE))
  
          avio_close(ofmt_ctx->pb);
  
      avformat_free_context(ofmt_ctx);
  
      if (ret < 0 && ret != AVERROR_EOF) {
  
          printf( "Error occurred.\n");
  
          return -1;
  
      }
  
      return 0;
  
  }

  Can anyone help me with this ?