ref: 9acd599496f6e8013cc2ccd18d105de17f49fca8
parent: b56d23c78ede1dc4f74b32bc0f6092d87e79553e
author: Sigrid Haflínudóttir <[email protected]>
date: Tue Jan 21 12:05:09 EST 2020
add daw/sample command, which converts raw "data" into a finite sample file
--- /dev/null
+++ b/sample/mkfile
@@ -1,0 +1,12 @@
+</$objtype/mkfile
+
+TARG=\
+ sample\
+
+BIN=/$objtype/bin/daw
+CFLAGS=$CFLAGS
+OFILES=sample.$O
+
+default:V: all
+
+</sys/src/cmd/mkone
--- /dev/null
+++ b/sample/sample.c
@@ -1,0 +1,72 @@
+#include <u.h>
+#include <libc.h>
+
+static void
+usage(void)
+{+ print("usage: %s [-b buf_frames] [-c channels]\n", argv0);+ exits("usage");+}
+
+void
+main(int argc, char **argv)
+{+ int bufsz, bufframes, framesz, chan, n, r, end, i;
+ float f;
+ u8int *b;
+
+ bufframes = 2048;
+ chan = 1;
+
+ ARGBEGIN{+ case 'b':
+ bufframes = atoi(EARGF(usage()));
+ break;
+ case 'c':
+ chan = atoi(EARGF(usage()));
+ break;
+ default:
+ usage();
+ }ARGEND
+
+ if (bufframes < 1)
+ sysfatal("invalid buffer size: %d frames", bufframes);+ if (chan < 1)
+ sysfatal("invalid number of channels: %d", chan);+
+ framesz = chan * 4;
+ bufsz = bufframes * framesz;
+ b = malloc(bufsz);
+
+ n = 0;
+ for (;;) {+ r = read(0, b+n, bufsz-n);
+ if (r < 0)
+ exits("read failed");+ else if (r == 0)
+ break;
+ n += r;
+
+ end = n & ~(framesz-1);
+ if (end < 1)
+ continue;
+
+ for (; end > 0; end -= framesz) {+ for (i = 0; i < chan; i++) {+ f = *(float*)(b + end - framesz - i*4);
+ if (f != 0)
+ goto out;
+ }
+ }
+out:
+ if (end == 0)
+ break;
+
+ if (write(1, b, end) != end)
+ exits("write failed");+ n -= end;
+ memmove(b, b+end, n);
+ }
+
+ exits(nil);
+}