From 9f95ff5b6ba01db09552b84a0ab79607060a2666 Mon Sep 17 00:00:00 2001 From: Ali Labbene Date: Wed, 11 Dec 2019 08:59:21 +0100 Subject: Official ARM version: v5.4.0 Add CMSIS V5.4.0, please refer to index.html available under \docs folder. Note: content of \CMSIS\Core\Include has been copied under \Include to keep the same structure used in existing projects, and thus avoid projects mass update Note: the following components have been removed from ARM original delivery (as not used in ST packages) - CMSIS_EW2018.pdf - .gitattributes - .gitignore - \Device - \CMSIS - \CoreValidation - \DAP - \Documentation - \DoxyGen - \Driver - \Pack - \RTOS\CMSIS_RTOS_Tutorial.pdf - \RTOS\RTX - \RTOS\Template - \RTOS2\RTX - \Utilities - All ARM/GCC projects files are deleted from \DSP, \RTOS and \RTOS2 Change-Id: Ia026c3f0f0d016627a4fb5a9032852c33d24b4d3 --- docs/DSP/html/group__ComplexFFT.html | 1006 ++++++++++++++++++++++++++++++++++ 1 file changed, 1006 insertions(+) create mode 100644 docs/DSP/html/group__ComplexFFT.html (limited to 'docs/DSP/html/group__ComplexFFT.html') diff --git a/docs/DSP/html/group__ComplexFFT.html b/docs/DSP/html/group__ComplexFFT.html new file mode 100644 index 0000000..6cd2383 --- /dev/null +++ b/docs/DSP/html/group__ComplexFFT.html @@ -0,0 +1,1006 @@ + + + + + +Complex FFT Functions +CMSIS-DSP: Complex FFT Functions + + + + + + + + + + + + + + +
+
+ + + + + + + +
+
CMSIS-DSP +  Version 1.5.2 +
+
CMSIS DSP Software Library
+
+
+ +
+
    + +
+
+ + + +
+
+ +
+
+
+ +
+ + + + +
+ +
+ +
+
+Content | +Functions
+
+
Complex FFT Functions
Transform Functions
+
+
+ + + + +

+Content

 Complex FFT Tables
 
+ + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + +

+Functions

void arm_cfft_f32 (const arm_cfft_instance_f32 *S, float32_t *p1, uint8_t ifftFlag, uint8_t bitReverseFlag)
 Processing function for the floating-point complex FFT. More...
 
void arm_cfft_q15 (const arm_cfft_instance_q15 *S, q15_t *p1, uint8_t ifftFlag, uint8_t bitReverseFlag)
 Processing function for the Q15 complex FFT. More...
 
void arm_cfft_q31 (const arm_cfft_instance_q31 *S, q31_t *p1, uint8_t ifftFlag, uint8_t bitReverseFlag)
 Processing function for the fixed-point complex FFT in Q31 format. More...
 
void arm_cfft_radix2_f32 (const arm_cfft_radix2_instance_f32 *S, float32_t *pSrc)
 Radix-2 CFFT/CIFFT. More...
 
arm_status arm_cfft_radix2_init_f32 (arm_cfft_radix2_instance_f32 *S, uint16_t fftLen, uint8_t ifftFlag, uint8_t bitReverseFlag)
 Initialization function for the floating-point CFFT/CIFFT. More...
 
arm_status arm_cfft_radix2_init_q15 (arm_cfft_radix2_instance_q15 *S, uint16_t fftLen, uint8_t ifftFlag, uint8_t bitReverseFlag)
 Initialization function for the Q15 CFFT/CIFFT. More...
 
arm_status arm_cfft_radix2_init_q31 (arm_cfft_radix2_instance_q31 *S, uint16_t fftLen, uint8_t ifftFlag, uint8_t bitReverseFlag)
 Initialization function for the Q31 CFFT/CIFFT. More...
 
void arm_cfft_radix2_q15 (const arm_cfft_radix2_instance_q15 *S, q15_t *pSrc)
 Processing function for the fixed-point CFFT/CIFFT. More...
 
void arm_cfft_radix2_q31 (const arm_cfft_radix2_instance_q31 *S, q31_t *pSrc)
 Processing function for the fixed-point CFFT/CIFFT. More...
 
void arm_cfft_radix4_f32 (const arm_cfft_radix4_instance_f32 *S, float32_t *pSrc)
 Processing function for the floating-point Radix-4 CFFT/CIFFT. More...
 
arm_status arm_cfft_radix4_init_f32 (arm_cfft_radix4_instance_f32 *S, uint16_t fftLen, uint8_t ifftFlag, uint8_t bitReverseFlag)
 Initialization function for the floating-point CFFT/CIFFT. More...
 
arm_status arm_cfft_radix4_init_q15 (arm_cfft_radix4_instance_q15 *S, uint16_t fftLen, uint8_t ifftFlag, uint8_t bitReverseFlag)
 Initialization function for the Q15 CFFT/CIFFT. More...
 
arm_status arm_cfft_radix4_init_q31 (arm_cfft_radix4_instance_q31 *S, uint16_t fftLen, uint8_t ifftFlag, uint8_t bitReverseFlag)
 Initialization function for the Q31 CFFT/CIFFT. More...
 
void arm_cfft_radix4_q15 (const arm_cfft_radix4_instance_q15 *S, q15_t *pSrc)
 Processing function for the Q15 CFFT/CIFFT. More...
 
void arm_cfft_radix4_q31 (const arm_cfft_radix4_instance_q31 *S, q31_t *pSrc)
 Processing function for the Q31 CFFT/CIFFT. More...
 
+

Description

+
The Fast Fourier Transform (FFT) is an efficient algorithm for computing the Discrete Fourier Transform (DFT). The FFT can be orders of magnitude faster than the DFT, especially for long lengths. The algorithms described in this section operate on complex data. A separate set of functions is devoted to handling of real sequences.
+
There are separate algorithms for handling floating-point, Q15, and Q31 data types. The algorithms available for each data type are described next.
+
The FFT functions operate in-place. That is, the array holding the input data will also be used to hold the corresponding result. The input data is complex and contains 2*fftLen interleaved values as shown below. 
 {real[0], imag[0], real[1], imag[1],..}
The FFT result will be contained in the same array and the frequency domain values will have the same interleaving.
+
Floating-point
The floating-point complex FFT uses a mixed-radix algorithm. Multiple radix-8 stages are performed along with a single radix-2 or radix-4 stage, as needed. The algorithm supports lengths of [16, 32, 64, ..., 4096] and each length uses a different twiddle factor table.
+
The function uses the standard FFT definition and output values may grow by a factor of fftLen when computing the forward transform. The inverse transform includes a scale of 1/fftLen as part of the calculation and this matches the textbook definition of the inverse FFT.
+
Pre-initialized data structures containing twiddle factors and bit reversal tables are provided and defined in arm_const_structs.h. Include this header in your function and then pass one of the constant structures as an argument to arm_cfft_f32. For example:
+
arm_cfft_f32(arm_cfft_sR_f32_len64, pSrc, 1, 1)
+
computes a 64-point inverse complex FFT including bit reversal. The data structures are treated as constant data and not modified during the calculation. The same data structure can be reused for multiple transforms including mixing forward and inverse transforms.
+
Earlier releases of the library provided separate radix-2 and radix-4 algorithms that operated on floating-point data. These functions are still provided but are deprecated. The older functions are slower and less general than the new functions.
+
An example of initialization of the constants for the arm_cfft_f32 function follows:
const static arm_cfft_instance_f32 *S;
+
...
+
switch (length) {
+
case 16:
+
S = &arm_cfft_sR_f32_len16;
+
break;
+
case 32:
+
S = &arm_cfft_sR_f32_len32;
+
break;
+
case 64:
+
S = &arm_cfft_sR_f32_len64;
+
break;
+
case 128:
+
S = &arm_cfft_sR_f32_len128;
+
break;
+
case 256:
+
S = &arm_cfft_sR_f32_len256;
+
break;
+
case 512:
+
S = &arm_cfft_sR_f32_len512;
+
break;
+
case 1024:
+
S = &arm_cfft_sR_f32_len1024;
+
break;
+
case 2048:
+
S = &arm_cfft_sR_f32_len2048;
+
break;
+
case 4096:
+
S = &arm_cfft_sR_f32_len4096;
+
break;
+
}
+
+
Q15 and Q31
The floating-point complex FFT uses a mixed-radix algorithm. Multiple radix-4 stages are performed along with a single radix-2 stage, as needed. The algorithm supports lengths of [16, 32, 64, ..., 4096] and each length uses a different twiddle factor table.
+
The function uses the standard FFT definition and output values may grow by a factor of fftLen when computing the forward transform. The inverse transform includes a scale of 1/fftLen as part of the calculation and this matches the textbook definition of the inverse FFT.
+
Pre-initialized data structures containing twiddle factors and bit reversal tables are provided and defined in arm_const_structs.h. Include this header in your function and then pass one of the constant structures as an argument to arm_cfft_q31. For example:
+
arm_cfft_q31(arm_cfft_sR_q31_len64, pSrc, 1, 1)
+
computes a 64-point inverse complex FFT including bit reversal. The data structures are treated as constant data and not modified during the calculation. The same data structure can be reused for multiple transforms including mixing forward and inverse transforms.
+
Earlier releases of the library provided separate radix-2 and radix-4 algorithms that operated on floating-point data. These functions are still provided but are deprecated. The older functions are slower and less general than the new functions.
+
An example of initialization of the constants for the arm_cfft_q31 function follows:
const static arm_cfft_instance_q31 *S;
+
...
+
switch (length) {
+
case 16:
+
S = &arm_cfft_sR_q31_len16;
+
break;
+
case 32:
+
S = &arm_cfft_sR_q31_len32;
+
break;
+
case 64:
+
S = &arm_cfft_sR_q31_len64;
+
break;
+
case 128:
+
S = &arm_cfft_sR_q31_len128;
+
break;
+
case 256:
+
S = &arm_cfft_sR_q31_len256;
+
break;
+
case 512:
+
S = &arm_cfft_sR_q31_len512;
+
break;
+
case 1024:
+
S = &arm_cfft_sR_q31_len1024;
+
break;
+
case 2048:
+
S = &arm_cfft_sR_q31_len2048;
+
break;
+
case 4096:
+
S = &arm_cfft_sR_q31_len4096;
+
break;
+
}
+
+

Function Documentation

+ +
+
+ + + + + + + + + + + + + + + + + + + + + + + + + + + + + + +
void arm_cfft_f32 (const arm_cfft_instance_f32 * S,
float32_t * p1,
uint8_t ifftFlag,
uint8_t bitReverseFlag 
)
+
+
Parameters
+ + + + + +
[in]*Spoints to an instance of the floating-point CFFT structure.
[in,out]*p1points to the complex data buffer of size 2*fftLen. Processing occurs in-place.
[in]ifftFlagflag that selects forward (ifftFlag=0) or inverse (ifftFlag=1) transform.
[in]bitReverseFlagflag that enables (bitReverseFlag=1) or disables (bitReverseFlag=0) bit reversal of output.
+
+
+
Returns
none.
+ +

References arm_bitreversal_32(), arm_cfft_radix8by2_f32(), arm_cfft_radix8by4_f32(), arm_radix8_butterfly_f32(), arm_cfft_instance_f32::bitRevLength, arm_cfft_instance_f32::fftLen, arm_cfft_instance_f32::pBitRevTable, and arm_cfft_instance_f32::pTwiddle.

+ +

Referenced by arm_rfft_fast_f32(), and main().

+ +
+
+ +
+
+ + + + + + + + + + + + + + + + + + + + + + + + + + + + + + +
void arm_cfft_q15 (const arm_cfft_instance_q15 * S,
q15_t * p1,
uint8_t ifftFlag,
uint8_t bitReverseFlag 
)
+
+
Parameters
+ + + + + +
[in]*Spoints to an instance of the Q15 CFFT structure.
[in,out]*p1points to the complex data buffer of size 2*fftLen. Processing occurs in-place.
[in]ifftFlagflag that selects forward (ifftFlag=0) or inverse (ifftFlag=1) transform.
[in]bitReverseFlagflag that enables (bitReverseFlag=1) or disables (bitReverseFlag=0) bit reversal of output.
+
+
+
Returns
none.
+ +

References arm_bitreversal_16(), arm_cfft_radix4by2_inverse_q15(), arm_cfft_radix4by2_q15(), arm_radix4_butterfly_inverse_q15(), arm_radix4_butterfly_q15(), arm_cfft_instance_q15::bitRevLength, arm_cfft_instance_q15::fftLen, arm_cfft_instance_q15::pBitRevTable, and arm_cfft_instance_q15::pTwiddle.

+ +

Referenced by arm_rfft_q15().

+ +
+
+ +
+
+ + + + + + + + + + + + + + + + + + + + + + + + + + + + + + +
void arm_cfft_q31 (const arm_cfft_instance_q31 * S,
q31_t * p1,
uint8_t ifftFlag,
uint8_t bitReverseFlag 
)
+
+
Parameters
+ + + + + +
[in]*Spoints to an instance of the fixed-point CFFT structure.
[in,out]*p1points to the complex data buffer of size 2*fftLen. Processing occurs in-place.
[in]ifftFlagflag that selects forward (ifftFlag=0) or inverse (ifftFlag=1) transform.
[in]bitReverseFlagflag that enables (bitReverseFlag=1) or disables (bitReverseFlag=0) bit reversal of output.
+
+
+
Returns
none.
+ +

References arm_bitreversal_32(), arm_cfft_radix4by2_inverse_q31(), arm_cfft_radix4by2_q31(), arm_radix4_butterfly_inverse_q31(), arm_radix4_butterfly_q31(), arm_cfft_instance_q31::bitRevLength, arm_cfft_instance_q31::fftLen, arm_cfft_instance_q31::pBitRevTable, and arm_cfft_instance_q31::pTwiddle.

+ +

Referenced by arm_rfft_q31().

+ +
+
+ +
+
+ + + + + + + + + + + + + + + + + + +
void arm_cfft_radix2_f32 (const arm_cfft_radix2_instance_f32 * S,
float32_t * pSrc 
)
+
+
Deprecated:
Do not use this function. It has been superseded by arm_cfft_f32 and will be removed in the future.
Parameters
+ + + +
[in]*Spoints to an instance of the floating-point Radix-2 CFFT/CIFFT structure.
[in,out]*pSrcpoints to the complex data buffer of size 2*fftLen. Processing occurs in-place.
+
+
+
Returns
none.
+
+ +

References arm_bitreversal_f32(), arm_radix2_butterfly_f32(), arm_radix2_butterfly_inverse_f32(), arm_cfft_radix2_instance_f32::bitReverseFlag, arm_cfft_radix2_instance_f32::bitRevFactor, arm_cfft_radix2_instance_f32::fftLen, arm_cfft_radix2_instance_f32::ifftFlag, arm_cfft_radix2_instance_f32::onebyfftLen, arm_cfft_radix2_instance_f32::pBitRevTable, arm_cfft_radix2_instance_f32::pTwiddle, and arm_cfft_radix2_instance_f32::twidCoefModifier.

+ +
+
+ +
+
+ + + + + + + + + + + + + + + + + + + + + + + + + + + + + + +
arm_status arm_cfft_radix2_init_f32 (arm_cfft_radix2_instance_f32 * S,
uint16_t fftLen,
uint8_t ifftFlag,
uint8_t bitReverseFlag 
)
+
+
Deprecated:
Do not use this function. It has been superseded by arm_cfft_f32 and will be removed in the future.
Parameters
+ + + + + +
[in,out]*Spoints to an instance of the floating-point CFFT/CIFFT structure.
[in]fftLenlength of the FFT.
[in]ifftFlagflag that selects forward (ifftFlag=0) or inverse (ifftFlag=1) transform.
[in]bitReverseFlagflag that enables (bitReverseFlag=1) or disables (bitReverseFlag=0) bit reversal of output.
+
+
+
Returns
The function returns ARM_MATH_SUCCESS if initialization is successful or ARM_MATH_ARGUMENT_ERROR if fftLen is not a supported value.
+
+
Description:
+
The parameter ifftFlag controls whether a forward or inverse transform is computed. Set(=1) ifftFlag for calculation of CIFFT otherwise CFFT is calculated
+
The parameter bitReverseFlag controls whether output is in normal order or bit reversed order. Set(=1) bitReverseFlag for output to be in normal order otherwise output is in bit reversed order.
+
The parameter fftLen Specifies length of CFFT/CIFFT process. Supported FFT Lengths are 16, 64, 256, 1024.
+
This Function also initializes Twiddle factor table pointer and Bit reversal table pointer.
+ +

References ARM_MATH_ARGUMENT_ERROR, ARM_MATH_SUCCESS, armBitRevTable, arm_cfft_radix2_instance_f32::bitReverseFlag, arm_cfft_radix2_instance_f32::bitRevFactor, arm_cfft_radix2_instance_f32::fftLen, ifftFlag, arm_cfft_radix2_instance_f32::ifftFlag, arm_cfft_radix2_instance_f32::onebyfftLen, arm_cfft_radix2_instance_f32::pBitRevTable, arm_cfft_radix2_instance_f32::pTwiddle, status, arm_cfft_radix2_instance_f32::twidCoefModifier, and twiddleCoef.

+ +
+
+ +
+
+ + + + + + + + + + + + + + + + + + + + + + + + + + + + + + +
arm_status arm_cfft_radix2_init_q15 (arm_cfft_radix2_instance_q15 * S,
uint16_t fftLen,
uint8_t ifftFlag,
uint8_t bitReverseFlag 
)
+
+
Deprecated:
Do not use this function. It has been superseded by arm_cfft_q15 and will be removed
Parameters
+ + + + + +
[in,out]*Spoints to an instance of the Q15 CFFT/CIFFT structure.
[in]fftLenlength of the FFT.
[in]ifftFlagflag that selects forward (ifftFlag=0) or inverse (ifftFlag=1) transform.
[in]bitReverseFlagflag that enables (bitReverseFlag=1) or disables (bitReverseFlag=0) bit reversal of output.
+
+
+
Returns
The function returns ARM_MATH_SUCCESS if initialization is successful or ARM_MATH_ARGUMENT_ERROR if fftLen is not a supported value.
+
+
Description:
+
The parameter ifftFlag controls whether a forward or inverse transform is computed. Set(=1) ifftFlag for calculation of CIFFT otherwise CFFT is calculated
+
The parameter bitReverseFlag controls whether output is in normal order or bit reversed order. Set(=1) bitReverseFlag for output to be in normal order otherwise output is in bit reversed order.
+
The parameter fftLen Specifies length of CFFT/CIFFT process. Supported FFT Lengths are 16, 64, 256, 1024.
+
This Function also initializes Twiddle factor table pointer and Bit reversal table pointer.
+ +

References ARM_MATH_ARGUMENT_ERROR, ARM_MATH_SUCCESS, armBitRevTable, arm_cfft_radix2_instance_q15::bitReverseFlag, arm_cfft_radix2_instance_q15::bitRevFactor, arm_cfft_radix2_instance_q15::fftLen, ifftFlag, arm_cfft_radix2_instance_q15::ifftFlag, arm_cfft_radix2_instance_q15::pBitRevTable, arm_cfft_radix2_instance_q15::pTwiddle, status, arm_cfft_radix2_instance_q15::twidCoefModifier, and twiddleCoef_4096_q15.

+ +
+
+ +
+
+ + + + + + + + + + + + + + + + + + + + + + + + + + + + + + +
arm_status arm_cfft_radix2_init_q31 (arm_cfft_radix2_instance_q31 * S,
uint16_t fftLen,
uint8_t ifftFlag,
uint8_t bitReverseFlag 
)
+
+
Deprecated:
Do not use this function. It has been superseded by arm_cfft_q31 and will be removed
Parameters
+ + + + + +
[in,out]*Spoints to an instance of the Q31 CFFT/CIFFT structure.
[in]fftLenlength of the FFT.
[in]ifftFlagflag that selects forward (ifftFlag=0) or inverse (ifftFlag=1) transform.
[in]bitReverseFlagflag that enables (bitReverseFlag=1) or disables (bitReverseFlag=0) bit reversal of output.
+
+
+
Returns
The function returns ARM_MATH_SUCCESS if initialization is successful or ARM_MATH_ARGUMENT_ERROR if fftLen is not a supported value.
+
+
Description:
+
The parameter ifftFlag controls whether a forward or inverse transform is computed. Set(=1) ifftFlag for calculation of CIFFT otherwise CFFT is calculated
+
The parameter bitReverseFlag controls whether output is in normal order or bit reversed order. Set(=1) bitReverseFlag for output to be in normal order otherwise output is in bit reversed order.
+
The parameter fftLen Specifies length of CFFT/CIFFT process. Supported FFT Lengths are 16, 64, 256, 1024.
+
This Function also initializes Twiddle factor table pointer and Bit reversal table pointer.
+ +

References ARM_MATH_ARGUMENT_ERROR, ARM_MATH_SUCCESS, armBitRevTable, arm_cfft_radix2_instance_q31::bitReverseFlag, arm_cfft_radix2_instance_q31::bitRevFactor, arm_cfft_radix2_instance_q31::fftLen, ifftFlag, arm_cfft_radix2_instance_q31::ifftFlag, arm_cfft_radix2_instance_q31::pBitRevTable, arm_cfft_radix2_instance_q31::pTwiddle, status, arm_cfft_radix2_instance_q31::twidCoefModifier, and twiddleCoef_4096_q31.

+ +
+
+ +
+
+ + + + + + + + + + + + + + + + + + +
void arm_cfft_radix2_q15 (const arm_cfft_radix2_instance_q15 * S,
q15_t * pSrc 
)
+
+
Deprecated:
Do not use this function. It has been superseded by arm_cfft_q15 and will be removed
Parameters
+ + + +
[in]*Spoints to an instance of the fixed-point CFFT/CIFFT structure.
[in,out]*pSrcpoints to the complex data buffer of size 2*fftLen. Processing occurs in-place.
+
+
+
Returns
none.
+
+ +

References arm_bitreversal_q15(), arm_radix2_butterfly_inverse_q15(), arm_radix2_butterfly_q15(), arm_cfft_radix2_instance_q15::bitRevFactor, arm_cfft_radix2_instance_q15::fftLen, arm_cfft_radix2_instance_q15::ifftFlag, arm_cfft_radix2_instance_q15::pBitRevTable, arm_cfft_radix2_instance_q15::pTwiddle, and arm_cfft_radix2_instance_q15::twidCoefModifier.

+ +
+
+ +
+
+ + + + + + + + + + + + + + + + + + +
void arm_cfft_radix2_q31 (const arm_cfft_radix2_instance_q31 * S,
q31_t * pSrc 
)
+
+
Deprecated:
Do not use this function. It has been superseded by arm_cfft_q31 and will be removed
Parameters
+ + + +
[in]*Spoints to an instance of the fixed-point CFFT/CIFFT structure.
[in,out]*pSrcpoints to the complex data buffer of size 2*fftLen. Processing occurs in-place.
+
+
+
Returns
none.
+
+ +

References arm_bitreversal_q31(), arm_radix2_butterfly_inverse_q31(), arm_radix2_butterfly_q31(), arm_cfft_radix2_instance_q31::bitRevFactor, arm_cfft_radix2_instance_q31::fftLen, arm_cfft_radix2_instance_q31::ifftFlag, arm_cfft_radix2_instance_q31::pBitRevTable, arm_cfft_radix2_instance_q31::pTwiddle, and arm_cfft_radix2_instance_q31::twidCoefModifier.

+ +
+
+ +
+
+ + + + + + + + + + + + + + + + + + +
void arm_cfft_radix4_f32 (const arm_cfft_radix4_instance_f32 * S,
float32_t * pSrc 
)
+
+
Deprecated:
Do not use this function. It has been superseded by arm_cfft_f32 and will be removed in the future.
Parameters
+ + + +
[in]*Spoints to an instance of the floating-point Radix-4 CFFT/CIFFT structure.
[in,out]*pSrcpoints to the complex data buffer of size 2*fftLen. Processing occurs in-place.
+
+
+
Returns
none.
+
+ +

References arm_bitreversal_f32(), arm_radix4_butterfly_f32(), arm_radix4_butterfly_inverse_f32(), arm_cfft_radix4_instance_f32::bitReverseFlag, arm_cfft_radix4_instance_f32::bitRevFactor, arm_cfft_radix4_instance_f32::fftLen, arm_cfft_radix4_instance_f32::ifftFlag, arm_cfft_radix4_instance_f32::onebyfftLen, arm_cfft_radix4_instance_f32::pBitRevTable, arm_cfft_radix4_instance_f32::pTwiddle, and arm_cfft_radix4_instance_f32::twidCoefModifier.

+ +

Referenced by main().

+ +
+
+ +
+
+ + + + + + + + + + + + + + + + + + + + + + + + + + + + + + +
arm_status arm_cfft_radix4_init_f32 (arm_cfft_radix4_instance_f32 * S,
uint16_t fftLen,
uint8_t ifftFlag,
uint8_t bitReverseFlag 
)
+
+
Deprecated:
Do not use this function. It has been superceded by arm_cfft_f32 and will be removed in the future.
Parameters
+ + + + + +
[in,out]*Spoints to an instance of the floating-point CFFT/CIFFT structure.
[in]fftLenlength of the FFT.
[in]ifftFlagflag that selects forward (ifftFlag=0) or inverse (ifftFlag=1) transform.
[in]bitReverseFlagflag that enables (bitReverseFlag=1) or disables (bitReverseFlag=0) bit reversal of output.
+
+
+
Returns
The function returns ARM_MATH_SUCCESS if initialization is successful or ARM_MATH_ARGUMENT_ERROR if fftLen is not a supported value.
+
+
Description:
+
The parameter ifftFlag controls whether a forward or inverse transform is computed. Set(=1) ifftFlag for calculation of CIFFT otherwise CFFT is calculated
+
The parameter bitReverseFlag controls whether output is in normal order or bit reversed order. Set(=1) bitReverseFlag for output to be in normal order otherwise output is in bit reversed order.
+
The parameter fftLen Specifies length of CFFT/CIFFT process. Supported FFT Lengths are 16, 64, 256, 1024.
+
This Function also initializes Twiddle factor table pointer and Bit reversal table pointer.
+ +

References ARM_MATH_ARGUMENT_ERROR, ARM_MATH_SUCCESS, armBitRevTable, arm_cfft_radix4_instance_f32::bitReverseFlag, arm_cfft_radix4_instance_f32::bitRevFactor, arm_cfft_radix4_instance_f32::fftLen, ifftFlag, arm_cfft_radix4_instance_f32::ifftFlag, arm_cfft_radix4_instance_f32::onebyfftLen, arm_cfft_radix4_instance_f32::pBitRevTable, arm_cfft_radix4_instance_f32::pTwiddle, status, arm_cfft_radix4_instance_f32::twidCoefModifier, and twiddleCoef.

+ +

Referenced by arm_rfft_init_f32(), and main().

+ +
+
+ +
+
+ + + + + + + + + + + + + + + + + + + + + + + + + + + + + + +
arm_status arm_cfft_radix4_init_q15 (arm_cfft_radix4_instance_q15 * S,
uint16_t fftLen,
uint8_t ifftFlag,
uint8_t bitReverseFlag 
)
+
+
Deprecated:
Do not use this function. It has been superseded by arm_cfft_q15 and will be removed
Parameters
+ + + + + +
[in,out]*Spoints to an instance of the Q15 CFFT/CIFFT structure.
[in]fftLenlength of the FFT.
[in]ifftFlagflag that selects forward (ifftFlag=0) or inverse (ifftFlag=1) transform.
[in]bitReverseFlagflag that enables (bitReverseFlag=1) or disables (bitReverseFlag=0) bit reversal of output.
+
+
+
Returns
The function returns ARM_MATH_SUCCESS if initialization is successful or ARM_MATH_ARGUMENT_ERROR if fftLen is not a supported value.
+
+
Description:
+
The parameter ifftFlag controls whether a forward or inverse transform is computed. Set(=1) ifftFlag for calculation of CIFFT otherwise CFFT is calculated
+
The parameter bitReverseFlag controls whether output is in normal order or bit reversed order. Set(=1) bitReverseFlag for output to be in normal order otherwise output is in bit reversed order.
+
The parameter fftLen Specifies length of CFFT/CIFFT process. Supported FFT Lengths are 16, 64, 256, 1024.
+
This Function also initializes Twiddle factor table pointer and Bit reversal table pointer.
+ +

References ARM_MATH_ARGUMENT_ERROR, ARM_MATH_SUCCESS, armBitRevTable, arm_cfft_radix4_instance_q15::bitReverseFlag, arm_cfft_radix4_instance_q15::bitRevFactor, arm_cfft_radix4_instance_q15::fftLen, ifftFlag, arm_cfft_radix4_instance_q15::ifftFlag, arm_cfft_radix4_instance_q15::pBitRevTable, arm_cfft_radix4_instance_q15::pTwiddle, status, arm_cfft_radix4_instance_q15::twidCoefModifier, and twiddleCoef_4096_q15.

+ +
+
+ +
+
+ + + + + + + + + + + + + + + + + + + + + + + + + + + + + + +
arm_status arm_cfft_radix4_init_q31 (arm_cfft_radix4_instance_q31 * S,
uint16_t fftLen,
uint8_t ifftFlag,
uint8_t bitReverseFlag 
)
+
+
Deprecated:
Do not use this function. It has been superseded by arm_cfft_q31 and will be removed
Parameters
+ + + + + +
[in,out]*Spoints to an instance of the Q31 CFFT/CIFFT structure.
[in]fftLenlength of the FFT.
[in]ifftFlagflag that selects forward (ifftFlag=0) or inverse (ifftFlag=1) transform.
[in]bitReverseFlagflag that enables (bitReverseFlag=1) or disables (bitReverseFlag=0) bit reversal of output.
+
+
+
Returns
The function returns ARM_MATH_SUCCESS if initialization is successful or ARM_MATH_ARGUMENT_ERROR if fftLen is not a supported value.
+
+
Description:
+
The parameter ifftFlag controls whether a forward or inverse transform is computed. Set(=1) ifftFlag for calculation of CIFFT otherwise CFFT is calculated
+
The parameter bitReverseFlag controls whether output is in normal order or bit reversed order. Set(=1) bitReverseFlag for output to be in normal order otherwise output is in bit reversed order.
+
The parameter fftLen Specifies length of CFFT/CIFFT process. Supported FFT Lengths are 16, 64, 256, 1024.
+
This Function also initializes Twiddle factor table pointer and Bit reversal table pointer.
+ +

References ARM_MATH_ARGUMENT_ERROR, ARM_MATH_SUCCESS, armBitRevTable, arm_cfft_radix4_instance_q31::bitReverseFlag, arm_cfft_radix4_instance_q31::bitRevFactor, arm_cfft_radix4_instance_q31::fftLen, ifftFlag, arm_cfft_radix4_instance_q31::ifftFlag, arm_cfft_radix4_instance_q31::pBitRevTable, arm_cfft_radix4_instance_q31::pTwiddle, status, arm_cfft_radix4_instance_q31::twidCoefModifier, and twiddleCoef_4096_q31.

+ +
+
+ +
+
+ + + + + + + + + + + + + + + + + + +
void arm_cfft_radix4_q15 (const arm_cfft_radix4_instance_q15 * S,
q15_t * pSrc 
)
+
+
Deprecated:
Do not use this function. It has been superseded by arm_cfft_q15 and will be removed
Parameters
+ + + +
[in]*Spoints to an instance of the Q15 CFFT/CIFFT structure.
[in,out]*pSrcpoints to the complex data buffer. Processing occurs in-place.
+
+
+
Returns
none.
+
+
Input and output formats:
+
Internally input is downscaled by 2 for every stage to avoid saturations inside CFFT/CIFFT process. Hence the output format is different for different FFT sizes. The input and output formats for different FFT sizes and number of bits to upscale are mentioned in the tables below for CFFT and CIFFT:
+
+CFFTQ15.gif +
+Input and Output Formats for Q15 CFFT
+
+CIFFTQ15.gif +
+Input and Output Formats for Q15 CIFFT
+
+ +

References arm_bitreversal_q15(), arm_radix4_butterfly_inverse_q15(), arm_radix4_butterfly_q15(), arm_cfft_radix4_instance_q15::bitReverseFlag, arm_cfft_radix4_instance_q15::bitRevFactor, arm_cfft_radix4_instance_q15::fftLen, arm_cfft_radix4_instance_q15::ifftFlag, arm_cfft_radix4_instance_q15::pBitRevTable, arm_cfft_radix4_instance_q15::pTwiddle, and arm_cfft_radix4_instance_q15::twidCoefModifier.

+ +
+
+ +
+
+ + + + + + + + + + + + + + + + + + +
void arm_cfft_radix4_q31 (const arm_cfft_radix4_instance_q31 * S,
q31_t * pSrc 
)
+
+
Deprecated:
Do not use this function. It has been superseded by arm_cfft_q31 and will be removed
Parameters
+ + + +
[in]*Spoints to an instance of the Q31 CFFT/CIFFT structure.
[in,out]*pSrcpoints to the complex data buffer of size 2*fftLen. Processing occurs in-place.
+
+
+
Returns
none.
+
+
Input and output formats:
+
Internally input is downscaled by 2 for every stage to avoid saturations inside CFFT/CIFFT process. Hence the output format is different for different FFT sizes. The input and output formats for different FFT sizes and number of bits to upscale are mentioned in the tables below for CFFT and CIFFT:
+
+CFFTQ31.gif +
+Input and Output Formats for Q31 CFFT
+
+CIFFTQ31.gif +
+Input and Output Formats for Q31 CIFFT
+
+ +

References arm_bitreversal_q31(), arm_radix4_butterfly_inverse_q31(), arm_radix4_butterfly_q31(), arm_cfft_radix4_instance_q31::bitReverseFlag, arm_cfft_radix4_instance_q31::bitRevFactor, arm_cfft_radix4_instance_q31::fftLen, arm_cfft_radix4_instance_q31::ifftFlag, arm_cfft_radix4_instance_q31::pBitRevTable, arm_cfft_radix4_instance_q31::pTwiddle, and arm_cfft_radix4_instance_q31::twidCoefModifier.

+ +
+
+
+
+ + + + -- cgit