Merge branch 'drop-the-bass'

CMakeLists.txt

@@ -111,23 +111,23 @@ set(BZC_PROJECT_INCLUDES ${BZC_PROJECT_INCLUDES}
 )
 
 ##############################################################################
-# BASS
-set(BZC_PROJECT_INCLUDES ${BZC_PROJECT_INCLUDES} ${CMAKE_SOURCE_DIR}/external/bass)
-if (APPLE)
-  set(BZC_PROJECT_LIBS ${BZC_PROJECT_LIBS} ${CMAKE_SOURCE_DIR}/external/bass/libbass.dylib)
-elseif (UNIX)
-  if (BONZOMATIC_64BIT)
-    set(BZC_PROJECT_LIBS ${BZC_PROJECT_LIBS} ${CMAKE_SOURCE_DIR}/external/bass/x64/libbass.so)
-  else ()
-    set(BZC_PROJECT_LIBS ${BZC_PROJECT_LIBS} ${CMAKE_SOURCE_DIR}/external/bass/x86/libbass.so)
-  endif ()
-elseif (WIN32)
-  if (BONZOMATIC_64BIT)
-    set(BZC_PROJECT_LIBS ${BZC_PROJECT_LIBS} ${CMAKE_SOURCE_DIR}/external/bass/x64/bass.lib)
-  else ()
-    set(BZC_PROJECT_LIBS ${BZC_PROJECT_LIBS} ${CMAKE_SOURCE_DIR}/external/bass/x86/bass.lib)
-  endif ()
+# mini_al
+set(BZC_PROJECT_INCLUDES ${BZC_PROJECT_INCLUDES} ${CMAKE_SOURCE_DIR}/external/mini_al)
+
+##############################################################################
+# kiss_fft
+set(KISSFFT_SRCS
+  ${CMAKE_SOURCE_DIR}/external/kiss_fft/kiss_fft.c
+  ${CMAKE_SOURCE_DIR}/external/kiss_fft/tools/kiss_fftr.c
+)
+add_library(bzc_kissfft STATIC ${KISSFFT_SRCS})
+target_include_directories(bzc_kissfft PUBLIC ${CMAKE_SOURCE_DIR}/external/kiss_fft ${CMAKE_SOURCE_DIR}/external/kiss_fft/tools)
+if (MSVC)
+  target_compile_options(bzc_kissfft PUBLIC "$<$<CONFIG:Release>:/MT>")
 endif ()
+set(BZC_PROJECT_INCLUDES ${BZC_PROJECT_INCLUDES} ${CMAKE_SOURCE_DIR}/external/kiss_fft)
+set(BZC_PROJECT_INCLUDES ${BZC_PROJECT_INCLUDES} ${CMAKE_SOURCE_DIR}/external/kiss_fft/tools)
+set(BZC_PROJECT_LIBS ${BZC_PROJECT_LIBS} bzc_kissfft)
 
 ##############################################################################
 # JSONXX
@@ -425,7 +425,6 @@ if (APPLE)
 
   set_source_files_properties(${BZC_RESOURCES_DATA} PROPERTIES MACOSX_PACKAGE_LOCATION Resources)
 
-  set(OSX_LIB_FILES ${CMAKE_SOURCE_DIR}/external/bass/libbass.dylib)
   set_source_files_properties(${OSX_LIB_FILES} PROPERTIES MACOSX_PACKAGE_LOCATION MacOS)
   set(BZC_PROJECT_SRCS ${BZC_PROJECT_SRCS} ${OSX_LIB_FILES})
 
@@ -482,12 +481,7 @@ endif ()
 target_include_directories(${BZC_EXE_NAME} PUBLIC ${BZC_PROJECT_INCLUDES})
 target_link_libraries(${BZC_EXE_NAME} ${BZC_PROJECT_LIBS})
 
-if (WIN32)
-  if (BONZOMATIC_64BIT)
-    add_custom_command(TARGET ${BZC_EXE_NAME} POST_BUILD COMMAND ${CMAKE_COMMAND} -E copy_if_different "${CMAKE_SOURCE_DIR}/external/bass/x64/bass.dll" $<TARGET_FILE_DIR:${BZC_EXE_NAME}>)
-  else ()
-    add_custom_command(TARGET ${BZC_EXE_NAME} POST_BUILD COMMAND ${CMAKE_COMMAND} -E copy_if_different "${CMAKE_SOURCE_DIR}/external/bass/x86/bass.dll" $<TARGET_FILE_DIR:${BZC_EXE_NAME}>)
-  endif ()
+if (MSVC)
   if (BONZOMATIC_NDI)
     if (BONZOMATIC_64BIT)
       add_custom_command(TARGET ${BZC_EXE_NAME} POST_BUILD COMMAND ${CMAKE_COMMAND} -E copy_if_different "${NDI_SDK_DIR}/Bin/x64/Processing.NDI.Lib.x64.dll" $<TARGET_FILE_DIR:${BZC_EXE_NAME}>)
@@ -499,11 +493,6 @@ endif ()
 
 ## install
 if (UNIX AND (NOT APPLE))
-  if (BONZOMATIC_64BIT)
-    install(FILES "${CMAKE_SOURCE_DIR}/external/bass/x64/libbass.so" DESTINATION lib)
-  else ()
-    install(FILES "${CMAKE_SOURCE_DIR}/external/bass/x86/libbass.so" DESTINATION lib)
-  endif ()
   install(TARGETS ${BZC_EXE_NAME} RUNTIME DESTINATION bin)
   install(FILES "${CMAKE_SOURCE_DIR}/data/unix/bonzomatic.desktop"
           DESTINATION "${CMAKE_INSTALL_PREFIX}/share/applications")

README.md

@@ -38,6 +38,7 @@ Create a `config.json` with e.g. the following contents: (all fields are optiona
   },
   "rendering":{
     "fftSmoothFactor": 0.9, // 0.0 means there's no smoothing at all, 1.0 means the FFT is completely smoothed flat
+    "fftAmplification": 1.0, // 1.0 means no change, larger values will result in brighter/stronger bands, smaller values in darker/weaker ones
   },
   "textures":{ // the keys below will become the shader variable names
     "texChecker":"textures/checker.png",
@@ -85,7 +86,8 @@ https://github.com/Gargaj/Bonzomatic/wiki/How-to-set-up-a-Live-Coding-compo
 ### Libraries and other included software
 - Scintilla editing component by the Scintilla Dev Team (http://www.scintilla.org/)
 - OpenGL Extension Wrangler Library by Nigel Stewart (http://glew.sourceforge.net/)
-- BASS.DLL by Ian Luck (http://www.un4seen.com/)
+- mini_al by David Reid (https://github.com/dr-soft/mini_al)
+- KISSFFT by Mark Borgerding (https://github.com/mborgerding/kissfft/)
 - STB Image and Truetype libraries by Sean Barrett (http://nothings.org/)
 - GLFW by whoever made GLFW (http://www.glfw.org/faq.html)
 - JSON++ by Hong Jiang (https://github.com/hjiang/jsonxx)

cmake_all.bat

@@ -61,7 +61,6 @@ cmake --build . --config Release
 mkdir ..\_package.%BNZ_OUT_DIR%\
 del ..\_package.%BNZ_OUT_DIR%\Bonzomatic_%BNZ_PLATFORM%_%BNZ_FLAVOR%.exe
 copy .\Release\Bonzomatic.exe ..\_package.%BNZ_OUT_DIR%\Bonzomatic_%BNZ_PLATFORM%_%BNZ_FLAVOR%.exe
-copy .\Release\bass.dll ..\_package.%BNZ_OUT_DIR%\
 copy .\Release\Processing.NDI.Lib.%BNZ_OUT_DIR%.dll ..\_package.%BNZ_OUT_DIR%\
 cd ..
 goto :eof

external/kiss_fft/.gitignore

+*.o
+*.swp
+*.so
+*.a
+*.dylib
+test/bm_fftw_double
+test/bm_fftw_float
+test/bm_fftw_int16_t
+test/bm_fftw_int32_t
+test/bm_fftw_simd
+test/bm_kiss_double
+test/bm_kiss_float
+test/bm_kiss_int16_t
+test/bm_kiss_int32_t
+test/bm_kiss_simd
+test/st_double
+test/st_float
+test/st_int16_t
+test/st_int32_t
+test/st_simd
+test/tkfc_double
+test/tkfc_float
+test/tkfc_int16_t
+test/tkfc_int32_t
+test/tkfc_simd
+test/tr_double
+test/tr_float
+test/tr_int16_t
+test/tr_int32_t
+test/tr_simd
+tools/fastconv_double
+tools/fastconv_float
+tools/fastconv_int16_t
+tools/fastconv_int32_t
+tools/fastconv_simd
+tools/fastconvr_double
+tools/fastconvr_float
+tools/fastconvr_int16_t
+tools/fastconvr_int32_t
+tools/fastconvr_simd
+tools/fft_double
+tools/fft_float
+tools/fft_int16_t
+tools/fft_int32_t
+tools/fft_simd

external/kiss_fft/.hgignore

+syntax:glob
+test/bm_*
+test/st_*
+test/tkfc_*
+test/tr_*
+tools/fastconv_*
+tools/fastconvr_*
+tools/fft_*
+*.swp
+*~

external/kiss_fft/CHANGELOG

+1.3.0 2012-07-18
+  removed non-standard malloc.h from kiss_fft.h
+
+  moved -lm to end of link line
+
+  checked various return values
+
+  converted python Numeric code to NumPy
+ 
+  fixed test of int32_t on 64 bit OS
+
+  added padding in a couple of places to allow SIMD alignment of structs
+
+1.2.9 2010-05-27
+  threadsafe ( including OpenMP )
+
+  first edition of kissfft.hh the C++ template fft engine
+ 
+1.2.8 
+  Changed memory.h to string.h -- apparently more standard
+  
+  Added openmp extensions.  This can have fairly linear speedups for larger FFT sizes.
+
+1.2.7 
+  Shrank the real-fft memory footprint. Thanks to Galen Seitz.
+
+1.2.6 (Nov 14, 2006) The "thanks to GenArts" release.
+  Added multi-dimensional real-optimized FFT, see tools/kiss_fftndr
+  Thanks go to GenArts, Inc. for sponsoring the development.
+
+1.2.5 (June 27, 2006) The "release for no good reason" release.
+   Changed some harmless code to make some compilers' warnings go away.
+   Added some more digits to pi -- why not.
+   Added kiss_fft_next_fast_size() function to help people decide how much to pad.
+   Changed multidimensional test from 8 dimensions to only 3 to avoid testing 
+   problems with fixed point (sorry Buckaroo Banzai).
+
+1.2.4 (Oct 27, 2005)   The "oops, inverse fixed point real fft was borked" release. 
+   Fixed scaling bug for inverse fixed point real fft -- also fixed test code that should've been failing.
+    Thanks to Jean-Marc Valin for bug report.
+
+   Use sys/types.h for more portable types than short,int,long => int16_t,int32_t,int64_t
+   If your system does not have these, you may need to define them -- but at least it breaks in a 
+   loud and easily fixable way -- unlike silently using the wrong size type.
+
+   Hopefully tools/psdpng.c is fixed -- thanks to Steve Kellog for pointing out the weirdness.
+
+1.2.3 (June 25, 2005)   The "you want to use WHAT as a sample" release.
+    Added ability to use 32 bit fixed point samples -- requires a 64 bit intermediate result, a la 'long long'
+
+    Added ability to do 4 FFTs in parallel by using SSE SIMD instructions. This is accomplished by
+    using the __m128 (vector of 4 floats) as kiss_fft_scalar.  Define USE_SIMD to use this.
+    
+    I know, I know ...  this is drifting a bit from the "kiss" principle, but the speed advantages 
+    make it worth it for some.  Also recent gcc makes it SOO easy to use vectors of 4 floats like a POD type.
+
+1.2.2 (May 6, 2005)   The Matthew release
+    Replaced fixed point division with multiply&shift.  Thanks to Jean-Marc Valin for 
+    discussions regarding.  Considerable speedup for fixed-point.
+
+    Corrected overflow protection in real fft routines  when using fixed point.
+    Finder's Credit goes to Robert Oschler of robodance for pointing me at the bug.
+    This also led to the CHECK_OVERFLOW_OP macro.
+
+1.2.1 (April 4, 2004) 
+    compiles cleanly with just about every -W warning flag under the sun
+
+    reorganized kiss_fft_state so it could be read-only/const. This may be useful for embedded systems
+    that are willing to predeclare twiddle factors, factorization.
+
+    Fixed C_MUL,S_MUL on 16-bit platforms.
+
+    tmpbuf will only be allocated if input & output buffers are same
+    scratchbuf will only be allocated for ffts that are not multiples of 2,3,5
+ 
+    NOTE: The tmpbuf,scratchbuf changes may require synchronization code for multi-threaded apps.
+
+
+1.2 (Feb 23, 2004)
+    interface change -- cfg object is forward declaration of struct instead of void*
+    This maintains type saftey and lets the compiler warn/error about stupid mistakes.
+            (prompted by suggestion from Erik de Castro Lopo)
+
+    small speed improvements
+
+    added psdpng.c -- sample utility that will create png spectrum "waterfalls" from an input file
+        ( not terribly useful yet)
+
+1.1.1 (Feb 1, 2004 )
+    minor bug fix -- only affects odd rank, in-place, multi-dimensional FFTs
+
+1.1 : (Jan 30,2004)
+    split sample_code/ into test/ and tools/
+
+    Removed 2-D fft and added N-D fft (arbitrary)
+
+    modified fftutil.c to allow multi-d FFTs
+
+    Modified core fft routine to allow an input stride via kiss_fft_stride()
+    (eased support of multi-D ffts)
+
+    Added fast convolution filtering (FIR filtering using overlap-scrap method, with tail scrap)
+
+    Add kfc.[ch]: the KISS FFT Cache. It takes care of allocs for you ( suggested by Oscar Lesta ).
+
+1.0.1 (Dec 15, 2003)
+    fixed bug that occurred when nfft==1. Thanks to Steven Johnson.
+    
+1.0 : (Dec 14, 2003)
+    changed kiss_fft function from using a single buffer, to two buffers.
+    If the same buffer pointer is supplied for both in and out, kiss will
+    manage the buffer copies.
+
+    added kiss_fft2d and kiss_fftr as separate source files (declarations in kiss_fft.h )
+
+0.4 :(Nov 4,2003) optimized for radix 2,3,4,5
+
+0.3 :(Oct 28, 2003) woops, version 2 didn't actually factor out any radices other than 2.
+        Thanks to Steven Johnson for finding this one.
+
+0.2 :(Oct 27, 2003) added mixed radix, only radix 2,4 optimized versions
+
+0.1 :(May 19 2003)  initial release, radix 2 only

external/kiss_fft/COPYING

+Copyright (c) 2003-2010 Mark Borgerding . All rights reserved.
+
+KISS FFT is provided under:
+
+  SPDX-License-Identifier: BSD-3-Clause
+
+Being under the terms of the BSD 3-clause "New" or "Revised" License,
+according with:
+
+  LICENSES/BSD-3-Clause
+

external/kiss_fft/LICENSES/BSD-3-Clause

+Valid-License-Identifier: BSD-3-Clause
+SPDX-URL: https://spdx.org/licenses/BSD-3-Clause.html
+Usage-Guide:
+  To use the BSD 3-clause "New" or "Revised" License put the following SPDX
+  tag/value pair into a comment according to the placement guidelines in
+  the licensing rules documentation:
+    SPDX-License-Identifier: BSD-3-Clause
+License-Text:
+
+Copyright (c) <year> <owner> . All rights reserved.
+
+Redistribution and use in source and binary forms, with or without modification,
+are permitted provided that the following conditions are met:
+
+1. Redistributions of source code must retain the above copyright notice,
+this list of conditions and the following disclaimer.
+
+2. Redistributions in binary form must reproduce the above copyright notice,
+this list of conditions and the following disclaimer in the documentation
+and/or other materials provided with the distribution.
+
+3. Neither the name of the copyright holder nor the names of its contributors
+may be used to endorse or promote products derived from this software without
+specific prior written permission.
+
+THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
+AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
+ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE
+LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
+DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
+SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER
+CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
+OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE
+USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.

external/kiss_fft/LICENSES/Unlicense

+Valid-License-Identifier: Unlicense
+SPDX-URL: https://spdx.org/licenses/Unlicense.html
+Usage-Guide:
+  To use the Unlicense put the following SPDX tag/value pair into a
+  comment according to the placement guidelines in the licensing rules
+  documentation:
+    SPDX-License-Identifier: Unlicense
+License-Text:
+
+This is free and unencumbered software released into the public domain.
+
+Anyone is free to copy, modify, publish, use, compile, sell, or distribute
+this software, either in source code form or as a compiled binary, for any
+purpose, commercial or non-commercial, and by any means.
+
+In jurisdictions that recognize copyright laws, the author or authors of this
+software dedicate any and all copyright interest in the software to the public
+domain. We make this dedication for the benefit of the public at large and
+to the detriment of our heirs and successors. We intend this dedication to be
+an overt act of relinquishment in perpetuity of all present and future rights
+to this software under copyright law.
+
+THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS
+FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS
+BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION
+OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH
+THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
+
+For more information, please refer to <http://unlicense.org/>

external/kiss_fft/Makefile

+KFVER=130
+
+ifeq ($(shell uname -s),Darwin)
+	SHARED := -Wl,-install_name,libkissfft.dylib -o libkissfft.dylib
+else
+	SHARED := -Wl,-soname,libkissfft.so -o libkissfft.so
+endif
+
+all:
+	gcc -Wall -fPIC -c *.c -Dkiss_fft_scalar=float -o kiss_fft.o
+	ar crus libkissfft.a kiss_fft.o
+	gcc -shared $(SHARED) kiss_fft.o
+
+install: all
+	cp libkissfft.so /usr/local/lib/
+
+doc:
+	@echo "Start by reading the README file.  If you want to build and test lots of stuff, do a 'make testall'"
+	@echo "but be aware that 'make testall' has dependencies that the basic kissfft software does not."
+	@echo "It is generally unneeded to run these tests yourself, unless you plan on changing the inner workings"
+	@echo "of kissfft and would like to make use of its regression tests."
+
+testall:
+	# The simd and int32_t types may or may not work on your machine 
+	make -C test DATATYPE=simd CFLAGADD="$(CFLAGADD)" test
+	make -C test DATATYPE=int32_t CFLAGADD="$(CFLAGADD)" test
+	make -C test DATATYPE=int16_t CFLAGADD="$(CFLAGADD)" test
+	make -C test DATATYPE=float CFLAGADD="$(CFLAGADD)" test
+	make -C test DATATYPE=double CFLAGADD="$(CFLAGADD)" test
+	echo "all tests passed"
+
+tarball: clean
+	hg archive -r v$(KFVER) -t tgz kiss_fft$(KFVER).tar.gz 
+	hg archive -r v$(KFVER) -t zip kiss_fft$(KFVER).zip
+
+clean:
+	cd test && make clean
+	cd tools && make clean
+	rm -f kiss_fft*.tar.gz *~ *.pyc kiss_fft*.zip 
+
+asm: kiss_fft.s
+
+kiss_fft.s: kiss_fft.c kiss_fft.h _kiss_fft_guts.h
+	[ -e kiss_fft.s ] && mv kiss_fft.s kiss_fft.s~ || true
+	gcc -S kiss_fft.c -O3 -mtune=native -ffast-math -fomit-frame-pointer -unroll-loops -dA -fverbose-asm 
+	gcc -o kiss_fft_short.s -S kiss_fft.c -O3 -mtune=native -ffast-math -fomit-frame-pointer -dA -fverbose-asm -DFIXED_POINT
+	[ -e kiss_fft.s~ ] && diff kiss_fft.s~ kiss_fft.s || true

external/kiss_fft/README

+KISS FFT - A mixed-radix Fast Fourier Transform based up on the principle, 
+"Keep It Simple, Stupid."
+
+    There are many great fft libraries already around.  Kiss FFT is not trying
+to be better than any of them.  It only attempts to be a reasonably efficient, 
+moderately useful FFT that can use fixed or floating data types and can be 
+incorporated into someone's C program in a few minutes with trivial licensing.
+
+USAGE:
+
+    The basic usage for 1-d complex FFT is:
+
+        #include "kiss_fft.h"
+
+        kiss_fft_cfg cfg = kiss_fft_alloc( nfft ,is_inverse_fft ,0,0 );
+
+        while ...
+        
+            ... // put kth sample in cx_in[k].r and cx_in[k].i
+            
+            kiss_fft( cfg , cx_in , cx_out );
+            
+            ... // transformed. DC is in cx_out[0].r and cx_out[0].i 
+            
+        kiss_fft_free(cfg);
+
+    Note: frequency-domain data is stored from dc up to 2pi.
+    so cx_out[0] is the dc bin of the FFT
+    and cx_out[nfft/2] is the Nyquist bin (if exists)
+
+    Declarations are in "kiss_fft.h", along with a brief description of the 
+functions you'll need to use. 
+
+Code definitions for 1d complex FFTs are in kiss_fft.c.
+
+You can do other cool stuff with the extras you'll find in tools/
+
+    * multi-dimensional FFTs 
+    * real-optimized FFTs  (returns the positive half-spectrum: (nfft/2+1) complex frequency bins)
+    * fast convolution FIR filtering (not available for fixed point)
+    * spectrum image creation
+
+The core fft and most tools/ code can be compiled to use float, double,
+ Q15 short or Q31 samples. The default is float.
+
+
+BACKGROUND:
+
+    I started coding this because I couldn't find a fixed point FFT that didn't 
+use assembly code.  I started with floating point numbers so I could get the 
+theory straight before working on fixed point issues.  In the end, I had a 
+little bit of code that could be recompiled easily to do ffts with short, float
+or double (other types should be easy too).  
+
+    Once I got my FFT working, I was curious about the speed compared to
+a well respected and highly optimized fft library.  I don't want to criticize 
+this great library, so let's call it FFT_BRANDX.
+During this process, I learned:
+
+    1. FFT_BRANDX has more than 100K lines of code. The core of kiss_fft is about 500 lines (cpx 1-d).
+    2. It took me an embarrassingly long time to get FFT_BRANDX working.
+    3. A simple program using FFT_BRANDX is 522KB. A similar program using kiss_fft is 18KB (without optimizing for size).
+    4. FFT_BRANDX is roughly twice as fast as KISS FFT in default mode.
+
+    It is wonderful that free, highly optimized libraries like FFT_BRANDX exist.
+But such libraries carry a huge burden of complexity necessary to extract every 
+last bit of performance.
+
+    Sometimes simpler is better, even if it's not better.
+
+FREQUENTLY ASKED QUESTIONS:
+	Q: Can I use kissfft in a project with a ___ license?
+	A: Yes.  See LICENSE below.
+
+	Q: Why don't I get the output I expect?
+	A: The two most common causes of this are 
+		1) scaling : is there a constant multiplier between what you got and what you want?
+		2) mixed build environment -- all code must be compiled with same preprocessor 
+		definitions for FIXED_POINT and kiss_fft_scalar
+
+	Q: Will you write/debug my code for me?
+	A: Probably not unless you pay me.  I am happy to answer pointed and topical questions, but 
+	I may refer you to a book, a forum, or some other resource.
+
+
+PERFORMANCE:
+    (on Athlon XP 2100+, with gcc 2.96, float data type)
+
+    Kiss performed 10000 1024-pt cpx ffts in .63 s of cpu time.
+    For comparison, it took md5sum twice as long to process the same amount of data.
+
+    Transforming 5 minutes of CD quality audio takes less than a second (nfft=1024). 
+
+DO NOT:
+    ... use Kiss if you need the Fastest Fourier Transform in the World
+    ... ask me to add features that will bloat the code
+
+UNDER THE HOOD:
+
+    Kiss FFT uses a time decimation, mixed-radix, out-of-place FFT. If you give it an input buffer  
+    and output buffer that are the same, a temporary buffer will be created to hold the data.
+
+    No static data is used.  The core routines of kiss_fft are thread-safe (but not all of the tools directory).
+
+    No scaling is done for the floating point version (for speed).  
+    Scaling is done both ways for the fixed-point version (for overflow prevention).
+
+    Optimized butterflies are used for factors 2,3,4, and 5. 
+
+    The real (i.e. not complex) optimization code only works for even length ffts.  It does two half-length
+    FFTs in parallel (packed into real&imag), and then combines them via twiddling.  The result is 
+    nfft/2+1 complex frequency bins from DC to Nyquist.  If you don't know what this means, search the web.
+
+    The fast convolution filtering uses the overlap-scrap method, slightly 
+    modified to put the scrap at the tail.
+
+LICENSE:
+    Revised BSD License, see COPYING for verbiage. 
+    Basically, "free to use&change, give credit where due, no guarantees"
+    Note this license is compatible with GPL at one end of the spectrum and closed, commercial software at 
+    the other end.  See http://www.fsf.org/licensing/licenses
+
+    A commercial license is available which removes the requirement for attribution.  Contact me for details.
+
+  
+TODO:
+    *) Add real optimization for odd length FFTs 
+    *) Document/revisit the input/output fft scaling
+    *) Make doc describing the overlap (tail) scrap fast convolution filtering in kiss_fastfir.c
+    *) Test all the ./tools/ code with fixed point (kiss_fastfir.c doesn't work, maybe others)
+
+AUTHOR:
+    Mark Borgerding
+    Mark@Borgerding.net

external/kiss_fft/README.simd

+If you are reading this, it means you think you may be interested in using the SIMD extensions in kissfft 
+to do 4 *separate* FFTs at once.
+
+Beware! Beyond here there be dragons!
+
+This API is not easy to use, is not well documented, and breaks the KISS principle.  
+
+
+Still reading? Okay, you may get rewarded for your patience with a considerable speedup 
+(2-3x) on intel x86 machines with SSE if you are willing to jump through some hoops.
+
+The basic idea is to use the packed 4 float __m128 data type as a scalar element.  
+This means that the format is pretty convoluted. It performs 4 FFTs per fft call on signals A,B,C,D.
+
+For complex data, the data is interlaced as follows:
+rA0,rB0,rC0,rD0,      iA0,iB0,iC0,iD0,   rA1,rB1,rC1,rD1, iA1,iB1,iC1,iD1 ...
+where "rA0" is the real part of the zeroth sample for signal A
+
+Real-only data is laid out:
+rA0,rB0,rC0,rD0,     rA1,rB1,rC1,rD1,      ... 
+
+Compile with gcc flags something like
+-O3 -mpreferred-stack-boundary=4  -DUSE_SIMD=1 -msse 
+
+Be aware of SIMD alignment.  This is the most likely cause of segfaults.  
+The code within kissfft uses scratch variables on the stack.  
+With SIMD, these must have addresses on 16 byte boundaries.  
+Search on "SIMD alignment" for more info.
+
+
+
+Robin at Divide Concept was kind enough to share his code for formatting to/from the SIMD kissfft.  
+I have not run it -- use it at your own risk.  It appears to do 4xN and Nx4 transpositions 
+(out of place).
+
+void SSETools::pack128(float* target, float* source, unsigned long size128)
+{
+   __m128* pDest = (__m128*)target;
+   __m128* pDestEnd = pDest+size128;
+   float* source0=source;
+   float* source1=source0+size128;
+   float* source2=source1+size128;
+   float* source3=source2+size128;
+
+   while(pDest<pDestEnd)
+   {
+       *pDest=_mm_set_ps(*source3,*source2,*source1,*source0);
+       source0++;
+       source1++;
+       source2++;
+       source3++;
+       pDest++;
+   }
+}
+
+void SSETools::unpack128(float* target, float* source, unsigned long size128)
+{
+
+   float* pSrc = source;
+   float* pSrcEnd = pSrc+size128*4;
+   float* target0=target;
+   float* target1=target0+size128;
+   float* target2=target1+size128;
+   float* target3=target2+size128;
+
+   while(pSrc<pSrcEnd)
+   {
+       *target0=pSrc[0];
+       *target1=pSrc[1];
+       *target2=pSrc[2];
+       *target3=pSrc[3];
+       target0++;
+       target1++;
+       target2++;
+       target3++;
+       pSrc+=4;
+   }
+}