1 files changed, 199 insertions, 0 deletions
diff --git a/src/lib/samplerate/samplerate.pas b/src/lib/samplerate/samplerate.pas
new file mode 100644
index 00000000..784b87da
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+++ b/src/lib/samplerate/samplerate.pas
@@ -0,0 +1,199 @@
+{*
+** Copyright (C) 2002-2004 Erik de Castro Lopo <erikd@mega-nerd.com>
+**
+** This program is free software; you can redistribute it and/or modify
+** it under the terms of the GNU General Public License as published by
+** the Free Software Foundation; either version 2 of the License, or
+** (at your option) any later version.
+**
+** This program is distributed in the hope that it will be useful,
+** but WITHOUT ANY WARRANTY; without even the implied warranty of
+** MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+** GNU General Public License for more details.
+**
+** You should have received a copy of the GNU General Public License
+** along with this program; if not, write to the Free Software
+** Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307, USA.
+*}
+
+{*
+** API documentation is available here:
+** http://www.mega-nerd.com/SRC/api.html
+*}
+
+unit samplerate;
+
+{$IFDEF FPC}
+  {$MODE DELPHI}
+  {$PACKENUM 4}    (* use 4-byte enums *)
+  {$PACKRECORDS C} (* GCC/Visual C/C++ compatible record packing *)
+{$ELSE}
+  {$MINENUMSIZE 4} (* use 4-byte enums *)
+{$ENDIF}
+
+
+interface
+
+uses
+  ctypes,
+  UConfig;
+
+const
+{$IFDEF MSWINDOWS}
+  LibName = 'libsamplerate-0.dll';
+{$ENDIF}
+{$IFDEF UNIX}
+  LibName = 'samplerate';
+  {$IFDEF DARWIN}
+    {$LINKLIB libsamplerate}
+  {$ENDIF}
+{$ENDIF}
+
+{ Opaque data type SRC_STATE. }
+type
+  PSRC_STATE = ^SRC_STATE;
+  SRC_STATE = record
+    // opaque
+  end;
+
+{ SRC_DATA is used to pass data to src_simple() and src_process().  }
+type
+  PSRC_DATA = ^SRC_DATA;
+  SRC_DATA = record
+    data_in, data_out: PCfloat;
+    input_frames, output_frames: clong;
+    input_frames_used, output_frames_gen: clong;
+    end_of_input: cint;
+    src_ratio: cdouble;
+  end;
+
+{ SRC_CB_DATA is used with callback based API.  }
+type
+  SRC_CB_DATA = record
+    frames: clong;
+    data_in: PCfloat;
+  end;
+
+{*
+** User supplied callback function type for use with src_callback_new()
+** and src_callback_read(). First parameter is the same pointer that was
+** passed into src_callback_new(). Second parameter is pointer to a
+** pointer. The user supplied callback function must modify *data to
+** point to the start of the user supplied float array. The user supplied
+** function must return the number of frames that **data points to.
+*}
+src_callback_t = function (cb_data: pointer; var data: PCfloat): clong; cdecl;
+
+{*
+** Standard initialisation function : return an anonymous pointer to the
+** internal state of the converter. Choose a converter from the enums below.
+** Error returned in *error.
+*}
+function src_new(converter_type: cint; channels: cint; error: PCint): PSRC_STATE; cdecl; external LibName;
+
+{*
+** Initilisation for callback based API : return an anonymous pointer to the
+** internal state of the converter. Choose a converter from the enums below.
+** The cb_data pointer can point to any data or be set to NULL. Whatever the
+** value, when processing, user supplied function "func" gets called with
+** cb_data as first parameter.
+*}
+function src_callback_new(func: src_callback_t; converter_type: cint; channels: cint;
+            error: Pinteger; cb_data: pointer): PSRC_STATE; cdecl; external LibName;
+
+{*
+** Cleanup all internal allocations.
+** Always returns NULL.
+*}
+function src_delete(state: PSRC_STATE): PSRC_STATE; cdecl; external LibName;
+
+{*
+** Standard processing function.
+** Returns non zero on error.
+*}
+function src_process(state: PSRC_STATE; data: PSRC_DATA): cint; cdecl; external LibName;
+
+{*
+** Callback based processing function. Read up to frames worth of data from
+** the converter int *data and return frames read or -1 on error.
+*}
+function src_callback_read(state: PSRC_STATE; src_ratio: cdouble;
+            frames: clong; data: PCfloat): clong; cdecl; external LibName;
+
+{*
+** Simple interface for performing a single conversion from input buffer to
+** output buffer at a fixed conversion ratio.
+** Simple interface does not require initialisation as it can only operate on
+** a single buffer worth of audio.
+*}
+function src_simple(data: PSRC_DATA; converter_type: cint; channels: cint): cint; cdecl; external LibName;
+
+{*
+** This library contains a number of different sample rate converters,
+** numbered 0 through N.
+**
+** Return a string giving either a name or a more full description of each
+** sample rate converter or NULL if no sample rate converter exists for
+** the given value. The converters are sequentially numbered from 0 to N.
+*}
+function src_get_name(converter_type: cint): {const} Pchar; cdecl; external LibName;
+function src_get_description(converter_type: cint): {const} Pchar; cdecl; external LibName;
+function src_get_version(): {const} Pchar; cdecl; external LibName;
+
+{*
+** Set a new SRC ratio. This allows step responses
+** in the conversion ratio.
+** Returns non zero on error.
+*}
+function src_set_ratio(state: PSRC_STATE; new_ratio: cdouble): cint; cdecl; external LibName;
+
+{*
+** Reset the internal SRC state.
+** Does not modify the quality settings.
+** Does not free any memory allocations.
+** Returns non zero on error.
+*}
+function src_reset(state: PSRC_STATE): cint; cdecl; external LibName;
+
+{*
+** Return TRUE if ratio is a valid conversion ratio, FALSE
+** otherwise.
+*}
+function src_is_valid_ratio(ratio: cdouble): cint; cdecl; external LibName;
+
+{*
+** Return an error number.
+*}
+function src_error(state: PSRC_STATE): cint; cdecl; external LibName;
+
+{*
+** Convert the error number into a string.
+*}
+function src_strerror(error: cint): {const} Pchar; cdecl; external LibName;
+
+{*
+** The following enums can be used to set the interpolator type
+** using the function src_set_converter().
+*}
+const
+  SRC_SINC_BEST_QUALITY   = 0;
+  SRC_SINC_MEDIUM_QUALITY = 1;
+  SRC_SINC_FASTEST        = 2;
+  SRC_ZERO_ORDER_HOLD     = 3;
+  SRC_LINEAR              = 4;
+
+{*
+** Extra helper functions for converting from short to float and
+** back again.
+*}
+procedure src_short_to_float_array(input: {const} PCshort; output: PCfloat; len: cint); cdecl; external LibName;
+procedure src_float_to_short_array(input: {const} PCfloat; output: PCshort; len: cint); cdecl; external LibName;
+
+{$IF LIBSAMPLERATE_VERSION >= 1003} // 0.1.3
+procedure src_int_to_float_array(input: {const} PCint; output: PCfloat; len: cint); cdecl; external LibName;
+procedure src_float_to_int_array(input: {const} PCfloat; output: PCint; len: cint); cdecl; external LibName;
+{$IFEND}
+
+implementation
+
+end.