changeset 659:536cfa209e7f

Sampling enhancements

Allow specification of a key with -k for doing sampling between a single
datum and the rest of the database.  (The implementation is slightly
icky, as mentioned in the previous commit message; hopefully this
situation will not remain for too long).

While we're at it, allow -r/--resultlength as a synonym for --nsamples
(if --nsamples is not given) in order better to reflect the analogy
between querying and sampling.

--- a/audioDB.cpp	Tue Jan 05 16:44:03 2010 +0000
+++ b/audioDB.cpp	Tue Jan 05 16:44:06 2010 +0000
@@ -332,7 +332,19 @@
     if(sequenceLength < 1 || sequenceLength > 1000) {
       error("seqlen out of range: 1 <= seqlen <= 1000");
     }
-    nsamples = args_info.nsamples_arg;
+    if(args_info.nsamples_given) {
+      nsamples = args_info.nsamples_arg;
+    } else if(args_info.resultlength_given) {
+      nsamples = args_info.resultlength_arg;
+    } else {
+      nsamples = args_info.nsamples_arg;
+    }
+    if(args_info.key_given) {
+      query_from_key = true;
+      key = args_info.key_arg;
+    }
+    
+
     return 0;
   }
 

--- a/sample.cpp	Tue Jan 05 16:44:03 2010 +0000
+++ b/sample.cpp	Tue Jan 05 16:44:06 2010 +0000
@@ -92,8 +92,23 @@
   double sumdist = 0;
   double sumlogdist = 0;
 
+  unsigned key_index = 0;
+  if(query_from_key) {
+    /* naughty use of internals here.  When this is part of the API,
+       it will be a legitimate use of internals.  -- CSR,
+       2010-01-05 */
+    key_index = (*adb->keymap)[key];
+    if(propTable[key_index] == 0) {
+      error("no samples of this length possible for key");
+    }
+  }
   for (unsigned int i = 0; i < nsamples;) {
-    unsigned track1 = random_track(propTable, total);
+    unsigned track1 = 0;
+    if(query_from_key) {
+      track1 = key_index;
+    } else {
+      track1 = random_track(propTable, total);
+    }
     unsigned track2 = random_track(propTable, total);
 
     if(track1 == track2)