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author | brunzelchen <brunzelchen@b956fd51-792f-4845-bead-9b4dfca2ff2c> | 2009-12-09 18:35:28 +0000 |
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committer | brunzelchen <brunzelchen@b956fd51-792f-4845-bead-9b4dfca2ff2c> | 2009-12-09 18:35:28 +0000 |
commit | e4f413fdcf003ac0ad20d145f61dd370994e79db (patch) | |
tree | 692f725464654d0a82cdb0888c28e4dd21d68517 /Medley/src/lib/samplerate | |
parent | d267ce95e1743fad0d383d1d7fe51e9b8bf5b66f (diff) | |
download | usdx-e4f413fdcf003ac0ad20d145f61dd370994e79db.tar.gz usdx-e4f413fdcf003ac0ad20d145f61dd370994e79db.tar.xz usdx-e4f413fdcf003ac0ad20d145f61dd370994e79db.zip |
just a first experimental version
git-svn-id: svn://svn.code.sf.net/p/ultrastardx/svn/branches/experimental@2011 b956fd51-792f-4845-bead-9b4dfca2ff2c
Diffstat (limited to 'Medley/src/lib/samplerate')
-rw-r--r-- | Medley/src/lib/samplerate/samplerate.pas | 199 |
1 files changed, 199 insertions, 0 deletions
diff --git a/Medley/src/lib/samplerate/samplerate.pas b/Medley/src/lib/samplerate/samplerate.pas new file mode 100644 index 00000000..784b87da --- /dev/null +++ b/Medley/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. |