reg the snd_pcm_hw_params_set_access function.

[Sakthi Subramanian <sakthi.subramaniang@xxxxxxxxx>]

Hi,

I have written a small application to record sample..

1. When i set snd_pcm_hw_params_set_access  to SND_PCM_ACCESS_RW_INTERLEAVED, and snd_pcm_hw_params_get_access i got snd_pcm_hw_params_get_access.

2. When i set the buffer size near it is always setting at 0. fails at    snd_pcm_hw_params (capture_handle, hw_params)) with  error -22.

Here is the code and output:

 

CODE :

-------------------

  if ((err = snd_pcm_open (&capture_handle, pcm_name, stream,open_mode)) < 0) {
   fprintf (stderr, "cannot open audio device %s  \n",
         snd_strerror (err));
   exit (1);
  }
  printf("\n snd_pcm_open DONE \n");
   err = snd_output_stdio_attach(&log, stderr, 0);  
  if ((err = snd_pcm_hw_params_malloc (&hw_params)) < 0) {
   fprintf (stderr, "cannot allocate hardware parameter structure (%s)\n",
     snd_strerror (err));
   exit (1);
  }

  printf("\n snd_pcm_hw_params_malloc DONE \n");  
    
  if ((err = snd_pcm_hw_params_any (capture_handle, hw_params)) < 0) {
   fprintf (stderr, "cannot initialize hardware parameter structure (%s)\n",
     snd_strerror (err));
   exit (1);
  }
  printf("\n snd_pcm_hw_params_any DONE \n"); 
  if ((err = snd_pcm_hw_params_set_format (capture_handle, hw_params, SND_PCM_FORMAT_S16_LE)) < 0) {
   fprintf (stderr, "cannot set sample format (%s)\n",
     snd_strerror (err));
   exit (1);
  }
   printf("\n snd_pcm_hw_params_set_format DONE \n"); 
  
  
  if ((err = snd_pcm_hw_params_set_access (capture_handle, hw_params, SND_PCM_ACCESS_RW_INTERLEAVED)) < 0) {
   fprintf (stderr, "cannot set access type (%s)\n",
     snd_strerror (err));
   exit (1);
  }
  printf("\n snd_pcm_hw_params_set_access DONE \n");  
        snd_pcm_hw_params_get_access(hw_params, (snd_pcm_access_t *) &val);
        printf("captureAudio access type = %s\n", snd_pcm_access_name((snd_pcm_access_t)val));
  

  if ((err = snd_pcm_hw_params_set_rate_near (capture_handle, hw_params, &hwparams.rate , 0)) < 0) {
   fprintf (stderr, "cannot set sample rate (%s)\n",
     snd_strerror (err));
   exit (1);
  }
  printf("\n snd_pcm_hw_params_set_rate_near DONE \n");      

  if ((err = snd_pcm_hw_params_set_channels (capture_handle, hw_params, 2)) < 0) {
   fprintf (stderr, "cannot set channel count (%s)\n",
     snd_strerror (err));
   exit (1);
  }

  printf("\n snd_pcm_hw_params_set_channels DONE \n");  

  err = snd_pcm_hw_params_set_buffer_size_near(capture_handle, hw_params,
            &buffer_frames);
  if (err < 0)
  { 
   fprintf (stderr, "cannot set buffer_size  (%s)\n",
     snd_strerror (err));
   exit (1);
   
  }
    printf("\n snd_pcm_hw_params_set_buffer_size_near  %d DONE \n", (int)buffer_frames);  
  err = snd_pcm_hw_params_get_buffer_size(hw_params, &buffer_size);
         if (err < 0) {
                 printf("Unable to get buffer size  %s\n", snd_strerror(err));

         }    
  
  err =  snd_pcm_hw_params_set_period_size_near(capture_handle, hw_params, &period_size, &dir);
  if (err < 0) {
                 printf("Unable to set buffer size  %s\n", snd_strerror(err));

         }   

   printf(" Ln %d : get buffer size  %d \n", __LINE__, (int) buffer_size);
   // FOR DEBUGGING SHOULD BE REMOVED LATER : GSS
  
 

        //display captureAudio card parameters
        printf(" handler name = %s\n", snd_pcm_name(capture_handle));
        printf("captureAudio pcm state = %s\n",
            snd_pcm_state_name(snd_pcm_state(capture_handle)));

        snd_pcm_hw_params_get_access(hw_params, (snd_pcm_access_t *) &val);
        printf("captureAudio access type = %s\n", snd_pcm_access_name((snd_pcm_access_t)val));

        snd_pcm_hw_params_get_format(hw_params,(snd_pcm_format_t *) &val);
        printf("captureAudio format = %s (%s)\n", snd_pcm_format_name((snd_pcm_format_t) val),
            snd_pcm_format_description((snd_pcm_format_t) val));

        snd_pcm_hw_params_get_format(hw_params, (snd_pcm_format_t *)&val);
         printf("format = '%s' (%s)\n", snd_pcm_format_name((snd_pcm_format_t)val),
        snd_pcm_format_description((snd_pcm_format_t)val));

  snd_pcm_hw_params_get_channels(hw_params, &val);
         printf("channels = %d\n", val);

         snd_pcm_hw_params_get_rate(hw_params,  &val1, &dir);
         printf("rate = %d bps\n", val);

         snd_pcm_hw_params_get_period_time(hw_params, & val1, &dir);
         printf("period time = %d us\n", val);

         snd_pcm_hw_params_get_period_size(hw_params, (snd_pcm_uframes_t *)&frames, &dir);
  
    printf("period size = %d frames\n", (int)frames);

         snd_pcm_hw_params_get_buffer_time(hw_params, &val1, &dir);
         printf("buffer time = %d us\n", val);

         snd_pcm_hw_params_get_buffer_size(hw_params,(snd_pcm_uframes_t *) &val);
         printf("buffer size = %d frames\n", val);

         snd_pcm_hw_params_get_periods(hw_params, &val1, &dir);
         printf("periods per buffer = %d frames\n", val);
 
  
  if ((err = snd_pcm_hw_params (capture_handle, hw_params)) < 0) {
   fprintf (stderr, "cannot set parameters (%s)\n",
   snd_strerror (err));
   printf("\n snd_pcm_hw_params FAILED :err :%d  \n", err); 
   exit (1);
  }
  printf("\n snd_pcm_hw_params DONE \n"); 
  

 bits_per_sample = snd_pcm_format_physical_width(hwparams.format);

 snd_pcm_hw_params_get_period_size(hw_params, &chunk_size, 0);
 snd_pcm_hw_params_get_buffer_size(hw_params, &buffer_size);
 
 bits_per_frame = bits_per_sample * hwparams.channels;
 chunk_bytes = chunk_size * bits_per_frame / 8;
 
 printf("\nchunk_size : %d \n", (int)chunk_size);
 printf("\n chunk_bytes :%d bits_per_frame :%dbits_per_sample :%d   \n", chunk_bytes, bits_per_frame, bits_per_sample);

 
  snd_pcm_hw_params_free (hw_params);
  printf("\n snd_SW and HW parameted set DONE \n");

 

OUTPUT:

snd_pcm_open DONE

 snd_pcm_hw_params_malloc DONE

 snd_pcm_hw_params_any DONE

 snd_pcm_hw_params_set_format DONE

 snd_pcm_hw_params_set_access DONE

 snd_pcm_hw_params_set_rate_near DONE

 snd_pcm_hw_params_set_channels DONE

 snd_pcm_hw_params_set_buffer_size_near  0 DONE
 Ln 177 : get buffer size  0
 handler name = default
captureAudio pcm state = OPEN
captureAudio access type = MMAP_COMPLEX
captureAudio format = S16_LE (Signed 16 bit Little Endian)
format = 'S16_LE' (Signed 16 bit Little Endian)
channels = 2
rate = 2 bps
period time = 2 us
period size = 0 frames
buffer time = 2 us
buffer size = 2 frames
periods per buffer = 2 frames

cannot set parameters ((null))
 printf Error = ffffffea
 snd_pcm_hw_params FAILED :err :-22

--------------------------------------------------

What is the issue here?

need ur inputs on this issue.

 

 

------------------------------------------------------------------------------
Special Offer-- Download ArcSight Logger for FREE (a $49 USD value)!
Finally, a world-class log management solution at an even better price-free!
Download using promo code Free_Logger_4_Dev2Dev. Offer expires 
February 28th, so secure your free ArcSight Logger TODAY! 
http://p.sf.net/sfu/arcsight-sfd2d

_______________________________________________
Alsa-user mailing list
Alsa-user@xxxxxxxxxxxxxxxxxxxxx
https://lists.sourceforge.net/lists/listinfo/alsa-user