Add spectrum analyzer demo app

This application is a demo which uses the QtMultimedia APIs to
capture and play back PCM audio.  While either recording or playback
is ongoing, the application performs real-time level and frequency
spectrum analysis.

Reviewed-by: Alessandro Portale

1 files changed, 37 insertions, 0 deletions

diff --git a/demos/spectrum/spectrum.pri b/demos/spectrum/spectrum.pri
new file mode 100644
index 0000000..c09aa0d
--- /dev/null
+++ b/demos/spectrum/spectrum.pri
@@ -0,0 +1,37 @@
+# The following macros allow certain features and debugging output
+# to be disabled / enabled at compile time.
+
+# Debug output from spectrum calculation
+DEFINES += LOG_SPECTRUMANALYSER
+
+# Debug output from waveform generation
+#DEFINES += LOG_WAVEFORM
+
+# Debug output from engine
+DEFINES += LOG_ENGINE
+
+# Dump input data to spectrum analyer, plus artefact data files
+#DEFINES += DUMP_SPECTRUMANALYSER
+
+# Dump captured audio data
+#DEFINES += DUMP_CAPTURED_AUDIO
+
+# Disable calculation of level
+#DEFINES += DISABLE_LEVEL
+
+# Disable calculation of frequency spectrum
+# If this macro is defined, the FFTReal DLL will not be built
+#DEFINES += DISABLE_FFT
+
+# Disables rendering of the waveform
+#DEFINES += DISABLE_WAVEFORM
+
+# If defined, superimpose the progress bar on the waveform
+DEFINES += SUPERIMPOSE_PROGRESS_ON_WAVEFORM
+
+# Perform spectrum analysis calculation in a separate thread
+DEFINES += SPECTRUM_ANALYSER_SEPARATE_THREAD
+
+# Suppress warnings about strncpy potentially being unsafe, emitted by MSVC
+win32: DEFINES += _CRT_SECURE_NO_WARNINGS
+