Wave file handling 2 (#4)

* force libsndfile to flush wav data to file after write. converted all `printf`s to `fprint`s to stderr opening the possibility of streaming data via stdout

* indentation

* added option to enable flushing wave file; it is now disabled by default

* added option to pipe raw pcm to stdout. removed redundant file open. updated help text.

Author: peads

include/dsd.h

@@ -104,7 +104,7 @@ typedef struct
   int audio_out;
   char wav_out_file[1024];
   SNDFILE *wav_out_f;
-  //int wav_out_fd;
+  int wav_out_major_type;
   int serial_baud;
   char serial_dev[1024];
   int serial_fd;
@@ -281,7 +281,7 @@ int readAmbe2450Data (dsd_opts * opts, dsd_state * state, char *ambe_d);
 void openMbeInFile (dsd_opts * opts, dsd_state * state);
 void closeMbeOutFile (dsd_opts * opts, dsd_state * state);
 void openMbeOutFile (dsd_opts * opts, dsd_state * state);
-void openWavOutFile (dsd_opts * opts, dsd_state * state);
+void openWavOutFile (dsd_opts * opts, __attribute__((unused)) dsd_state * state);
 void closeWavOutFile (dsd_opts * opts, dsd_state * state);
 void printFrameInfo (dsd_opts * opts, dsd_state * state);
 void processFrame (dsd_opts * opts, dsd_state * state);

src/dsd_file.c

@@ -316,14 +316,16 @@ openMbeOutFile (dsd_opts * opts, dsd_state * state)
     fflush (opts->mbe_out_f);
 }
 
-void openWavOutFile (dsd_opts *opts, dsd_state *state) {
+void openWavOutFile(dsd_opts *opts, __attribute__((unused)) dsd_state *state) {
+
     SF_INFO info;
     info.samplerate = 8000;
     info.channels = 1;
-    info.format = SF_FORMAT_WAV | SF_FORMAT_PCM_16 | SF_ENDIAN_LITTLE;
+    info.format = opts->wav_out_major_type | SF_FORMAT_PCM_16 | SF_ENDIAN_LITTLE;
     opts->wav_out_f = sf_open(opts->wav_out_file, SFM_WRITE, &info);
 
     if (!opts->wav_out_f) {
+        perror(NULL);
         fprintf(stderr, "Error - could not open wav output file %s\n", opts->wav_out_file);
         return;
     }

src/dsd_main.c

@@ -118,7 +118,7 @@ initOpts (dsd_opts * opts)
     opts->audio_out = 1;
     opts->wav_out_file[0] = 0;
     opts->wav_out_f = NULL;
-    //opts->wav_out_fd = -1;
+    opts->wav_out_major_type = SF_FORMAT_WAV;
     opts->serial_baud = 115200;
     sprintf (opts->serial_dev, "/dev/ttyUSB0");
     opts->resume = 0;
@@ -276,7 +276,7 @@ usage ()
     fprintf(stderr, "  -r <files>    Read/Play saved mbe data from file(s)\n");
     fprintf(stderr, "  -g <num>      Audio output gain (default = 0 = auto, disable = -1)\n");
     fprintf(stderr, "  -n            Do not send synthesized speech to audio output device\n");
-    fprintf(stderr, "  -w <file>     Output synthesized speech to a .wav file\n");
+    fprintf(stderr, "  -w - | <file> Output synthesized speech to a .wav file, or pipe raw PCM to stdout; both are mono, 8kHz, 16-bit, signed-int\n");
     fprintf(stderr, "  -a            Display port audio devices\n");
     fprintf(stderr, "\n");
     fprintf(stderr, "Scanner control options:\n");
@@ -576,10 +576,17 @@ main (int argc, char **argv)
                 fprintf(stderr, "Disabling audio output to soundcard.\n");
                 break;
             case 'w':
+                // TODO consider: should piping to stdout imply '-q' as well?
+                if (!strcmp("-", optarg)) {
+                    checkFileError(freopen(NULL, "wb", stdout));
+                    opts.audio_out = 0;
+                    opts.wav_out_major_type = SF_FORMAT_RAW;
+//                    opts.errorbars = 0;
+//                    opts.verbose = 0;
+                }
                 strncpy(opts.wav_out_file, optarg, 1023);
                 opts.wav_out_file[1023] = '\0';
                 fprintf(stderr, "Writing audio to file %s\n", opts.wav_out_file);
-                openWavOutFile (&opts, &state);
                 break;
             case 'B':
                 sscanf (optarg, "%d", &opts.serial_baud);