Move library tree where it belongs

lib-src/libscorealign/audiomixerreader.cpp

@@ -0,0 +1,78 @@
+/* audiomixerreader.cpp -- implements a class to read samples from Audacity
+*
+* 17-Jun-08  RBD created based on audiofilereader.cpp
+*/
+#include "assert.h"
+#include "stdlib.h"
+#include "audioreader.h"
+#include "allegro.h"
+#include "scorealign-glue.h"
+#include "audiomixerreader.h"
+
+double Audio_mixer_reader::get_sample_rate()
+{
+    return sample_rate;
+}
+
+
+Audio_mixer_reader::Audio_mixer_reader(void *mixer_, 
+        mixer_process_fn fn_ptr, int chans, 
+        double srate, double end_time)
+{
+    mixer = mixer_; // store in member variable
+    mixer_process = fn_ptr;
+    buffer = NULL;
+    buffer_len = 0;
+    index = 0;
+    channels = chans;
+    sample_rate = srate;
+    total_frames = end_time * srate + 0.5 /* for rounding */;
+}
+
+
+long Audio_mixer_reader::get_frames()
+{
+    // precondition: mixer is valid and no samples have been read
+    return total_frames;
+}
+
+
+long Audio_mixer_reader::read(float *data, long n)
+{
+    for (int i = 0; i < n; i++) { // fill data
+        float sum = 0;
+        // note: assume mixer returns stereo (interleaved)
+        for (int chan = 0; chan < channels; chan++) {
+            // sum over channels within a frame
+            if (index >= buffer_len * channels) {
+                buffer_len = 
+                   (*mixer_process) (mixer, &buffer, AMR_BUFFER_FRAMES);
+                // frame_count = mixer->Process(AMR_BUFFER_FRAMES);
+                // buffer = (float *) mixer->GetBuffer();
+                index = 0;
+                if (buffer_len == 0) { // no more samples to read
+                    // but we processed i
+                    return i;
+                }
+            }
+            sum += buffer[index++];
+        }
+        data[i] = sum;
+    }
+    return n; // when end is reached, n will be 0, but the caller shouldn't
+              // be asking for samples beyond the end because the caller knows
+              // how many samples to ask for.
+}
+
+void Audio_mixer_reader::close()
+{
+    // mixer is deleted by the creator of this object, so don't delete here
+    buffer = NULL; 
+}
+
+void Audio_mixer_reader::print_info()
+{
+    printf("   Audacity mixer at @ %p\n", mixer);
+    printf("   sample rate %g\n", get_sample_rate());
+    printf("   total frames %d\n", get_frames());
+}