Recherche avancée

Sur d’autres sites (5622)

• Sending big packets gets Bad Address error

  30 mars 2012, par Roi

  Im writing a live webcam stream using ffmpeg and sdl on C.
  my platform is linux.

  my application is a client server based.
  The client is reading from the webcam, produce an AVPacket, then send to server.

  My problem is, that the AVPacket struct has a member named data which is approximately 600k.
  At first, i had not checked the send() return value,
  So, of course the packet had failed to send completely.

  But after I checked, the send() returns Bad Address error at the second iteration of the big packet.
  the length of the data packet must be correct because is supplied from the AVPacket struct.

  It sends 2 members of the AVPacket before, so the server is up and functional.

  The problematic section :

      int send_video_data(video_client_t *client, void* buf, int length)
  
      {
  
          int rc;
  
  
  
          while (length > 0)
  
          {
  
             if ((rc = send(client->sockfd, buf, length, 0)) == -1) {
  
                       perror("failed sending data to server");
  
                       exit(1);
  
              }
  
  
  
              length-=rc;
  
              buf+=rc;
  
          }
  
  
  
          return 0;
  
  
  
      }

  Any one got any ideas why it's not working ?
  Thanks in advanced !

• Decode audio using libavcodec and play using libAO ?

  21 mars 2012, par Ashika Umanga Umagiliya

  I use following code snippet to decode audio files (tested with MP3,WAV,WMV).

  But when it plays the audio , it just gives static sounds and crashes time to time.
  Any hints on what i am doing wrong here ?

  #include 
  
  #include 
  
  #include 
  
  #include 
  
  
  
  
  
  extern "C" {
  
  #include "libavutil/mathematics.h"
  
  #include "libavformat/avformat.h"
  
  #include "libswscale/swscale.h"
  
  #include <ao></ao>ao.h>
  
  
  
  }
  
  
  
  void die(const char *msg)
  
  {
  
      fprintf(stderr,"%s\n",msg);
  
      exit(1);
  
  }
  
  
  
  int main(int argc, char **argv)
  
  {
  
  
  
      const char* input_filename=argv[1];
  
  
  
      //avcodec_register_all();
  
      av_register_all();
  
      //av_ini
  
  
  
      AVFormatContext* container=avformat_alloc_context();
  
      if(avformat_open_input(&amp;container,input_filename,NULL,NULL)&lt;0){
  
          die("Could not open file");
  
      }
  
  
  
      if(av_find_stream_info(container)&lt;0){
  
          die("Could not find file info");
  
      }
  
      av_dump_format(container,0,input_filename,false);
  
  
  
      int stream_id=-1;
  
      int i;
  
      for(i=0;inb_streams;i++){
  
          if(container->streams[i]->codec->codec_type==AVMEDIA_TYPE_AUDIO){
  
              stream_id=i;
  
              break;
  
          }
  
      }
  
      if(stream_id==-1){
  
          die("Could not find Audio Stream");
  
      }
  
  
  
      AVDictionary *metadata=container->metadata;
  
  
  
      AVCodecContext *ctx=container->streams[stream_id]->codec;
  
      AVCodec *codec=avcodec_find_decoder(ctx->codec_id);
  
  
  
      if(codec==NULL){
  
          die("cannot find codec!");
  
      }
  
  
  
      if(avcodec_open(ctx,codec)&lt;0){
  
          die("Codec cannot be found");
  
      }
  
  
  
      //ctx=avcodec_alloc_context3(codec);
  
  
  
      //initialize AO lib
  
      ao_initialize();
  
  
  
      int driver=ao_default_driver_id();
  
  
  
      ao_sample_format sformat;
  
      sformat.bits=16;
  
      sformat.channels=2;
  
      sformat.rate=44100;
  
      sformat.byte_format=AO_FMT_NATIVE;
  
      sformat.matrix=0;
  
  
  
      ao_device *adevice=ao_open_live(driver,&amp;sformat,NULL);
  
      //end of init AO LIB
  
  
  
      AVPacket packet;
  
      av_init_packet(&amp;packet);
  
  
  
      AVFrame *frame=avcodec_alloc_frame();
  
  
  
      int buffer_size=AVCODEC_MAX_AUDIO_FRAME_SIZE;
  
      uint8_t buffer[buffer_size];
  
      packet.data=buffer;
  
      packet.size =buffer_size;
  
  
  
  
  
  
  
      int len;
  
      int frameFinished=0;
  
      while(av_read_frame(container,&amp;packet)>=0)
  
      {
  
  
  
          if(packet.stream_index==stream_id){
  
              //printf("Audio Frame read  \n");
  
              int len=avcodec_decode_audio4(ctx,frame,&amp;frameFinished,&amp;packet);
  
              //frame->
  
              if(frameFinished){
  
                  //printf("Finished reading Frame %d %d\n",packet.size,len);
  
                  ao_play(adevice, (char*)frame->data, len);
  
              }
  
  
  
          }
  
  
  
  
  
      }
  
  
  
      av_close_input_file(container);
  
      ao_shutdown();
  
      return 0;
  
  }

• PHP ffmpeg exec returns null

  19 mars 2012, par benedict_w

  I'm trying to run ffmpeg through a PHP exec call, I've been debugging for a while and looked at lot of responses on here, but still not found any answers...

  My simplified call is :

  $cmd = 'ffmpeg 2>&1';
  
  
  
  exec(escapeshellcmd($cmd), $stdout, $stderr);
  
  
  
  var_dump($stderr);
  
  var_dump($stdout);
  
  var_dump($cmd);
  
  exit;

  My output is $stderr = int(1) and $stdout = array(0)

  Also I tried shell_exec($cmd) which returns NULL.

  cmd.exe has permissions set for the IUSR account - e.g. I can run $cmd = 'dir' and see a directory listing output.

  PHP is not running in safe mode.

  The ffmpeg.exe is in the same directory as my php file, but I have the same response giving an absolute path to the ffmpeg.exe file in $cmd.

  ffmpeg is executing fine from the command line.

  I'm running Windows XP, IIS and PHP 5.3.

  EDIT :

  If I run 'ffmpeg -h' I get the help commands, which must indicated that ffmpeg is recognised

  I've increased the PHP memory limit to 1024 - no luck.