convert: Add sc12-sc16 converters

Create missing sc12-sc16 and sc16-sc12 type converters. To avoid
replicating the full sc12 converter class object, overload the
converter calls with C++11 std::enable_if metafunctions. When
used with std::is_floating and std::is_integral templates, this
allow a single template interface with compile time function
selection and static type checking.

Note the below std::enable_if interface is confusing, but quite
effective in this case.

  typename enable_if<is_floating_point<type>::value>::type* = NULL

Fixes: #966
Related: #967, #1721

1 files changed, 28 insertions, 3 deletions

diff --git a/host/tests/convert_test.cpp b/host/tests/convert_test.cpp
index af2828a17..982007d4e 100644
--- a/host/tests/convert_test.cpp
+++ b/host/tests/convert_test.cpp
@@ -70,13 +70,13 @@ template <typename Range> static void loopback(
  * Test short conversion
  **********************************************************************/
 static void test_convert_types_sc16(
-    size_t nsamps, convert::id_type &id, const int extra_div = 1
+    size_t nsamps, convert::id_type &id, const int extra_div = 1, int mask = 0xffff
 ){
     //fill the input samples
     std::vector<sc16_t> input(nsamps), output(nsamps);
     for(sc16_t &in:  input) in = sc16_t(
-        short((float((std::rand())/(double(RAND_MAX)/2)) - 1)*32767/extra_div),
-        short((float((std::rand())/(double(RAND_MAX)/2)) - 1)*32767/extra_div)
+        short((float((std::rand())/(double(RAND_MAX)/2)) - 1)*32767/extra_div) & mask,
+        short((float((std::rand())/(double(RAND_MAX)/2)) - 1)*32767/extra_div) & mask
     );
 
     //run the loopback and test
@@ -235,6 +235,31 @@ BOOST_AUTO_TEST_CASE(test_convert_types_be_sc12_with_fc32){
     }
 }
 
+BOOST_AUTO_TEST_CASE(test_convert_types_le_sc16_and_sc12){
+    convert::id_type id;
+    id.input_format = "sc16";
+    id.num_inputs = 1;
+    id.num_outputs = 1;
+
+    //try various lengths to test edge cases
+    id.output_format = "sc12_item32_le";
+    for (size_t nsamps = 1; nsamps < 16; nsamps++){
+        test_convert_types_sc16(nsamps, id, 1, 0xfff0);
+    }
+}
+
+BOOST_AUTO_TEST_CASE(test_convert_types_be_sc16_and_sc12){
+    convert::id_type id;
+    id.input_format = "sc16";
+    id.num_inputs = 1;
+    id.num_outputs = 1;
+
+    id.output_format = "sc12_item32_be";
+    for (size_t nsamps = 1; nsamps < 16; nsamps++){
+        test_convert_types_sc16(nsamps, id, 1, 0xfff0);
+    }
+}
+
 /***********************************************************************
  * Test float to/from fc32 conversion loopback
  **********************************************************************/