Create ml_sampler.md

Author: marcel-licence

extras/ml_sampler.md

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+# Sampler
+This synthesizer module is made to playback samples from RAM or FLASH memory.
+It allows to manipulate the playback by changing the pitch, volume and tweak parameters like ADSR (attack, decay, sustain, release).
+In addition to that it is possible to loop samples.
+
+To use the **sampler** you need to include ml_sampler.h into your project:
+```cpp
+#include <ml_sampler.h>
+
+```
+
+The sampler requires an initialization by calling its init routine for example from the setup():
+```cpp
+#include <ml_sampler.h>
+
+#define SAMPLE_RATE 44100
+
+void setup(void)
+{
+  Sampler_Init(SAMPLE_RATE);
+  /*
+   * some other setup routines might be called here
+   */
+}
+```
+
+
+## playing samples from FLASH
+### preparing samples
+Samples can be played directly from FLASH when they are compiled into the program code.
+It is possible to convert wav-files into c files into a data array.
+For example prepare a 16bit mono wav-file and store it as test.wav.
+[Audacity](https://www.audacity.de/) can be used for this conversation
+![image](https://github.com/user-attachments/assets/7cbfe52e-24f7-45c9-a8a6-a54b0d1aa272)
+
+Then you can use [Bin2c](https://www.segger.com/free-utilities/bin2c/) to convert it to a c-file.
+You will find an array in the c-file:
+```cpp
+static const unsigned char _actest[55164UL + 1] = {
+```
+which can be used as a sample in the sampler by loading it:
+```cpp
+#include <ml_sampler.h>
+
+#define SAMPLE_RATE 44100
+
+void setup(void)
+{
+  Sampler_Init(SAMPLE_RATE);
+  Sampler_NewSampleStatic(_actest, sizeof(_actest));
+  /*
+   * some other setup routines might be called here
+   */
+}
+```
+Now the sampler is ready to playback the loaded sample.