FFmpeg
|
#include <inttypes.h>
#include "libavutil/common.h"
#include "mathops.h"
#include "lsp.h"
#include "libavcodec/mips/lsp_mips.h"
#include "libavutil/avassert.h"
Go to the source code of this file.
Macros | |
#define | FRAC_BITS 14 |
Functions | |
void | ff_acelp_reorder_lsf (int16_t *lsfq, int lsfq_min_distance, int lsfq_min, int lsfq_max, int lp_order) |
(I.F) means fixed-point value with F fractional and I integer bits More... | |
void | ff_set_min_dist_lsf (float *lsf, double min_spacing, int size) |
Adjust the quantized LSFs so they are increasing and not too close. More... | |
static int16_t | ff_cos (uint16_t arg) |
void | ff_acelp_lsf2lsp (int16_t *lsp, const int16_t *lsf, int lp_order) |
Convert LSF to LSP. More... | |
void | ff_acelp_lsf2lspd (double *lsp, const float *lsf, int lp_order) |
Floating point version of ff_acelp_lsf2lsp() More... | |
static void | lsp2poly (int *f, const int16_t *lsp, int lp_half_order) |
decodes polynomial coefficients from LSP More... | |
void | ff_acelp_lsp2lpc (int16_t *lp, const int16_t *lsp, int lp_half_order) |
LSP to LP conversion (3.2.6 of G.729) More... | |
void | ff_amrwb_lsp2lpc (const double *lsp, float *lp, int lp_order) |
LSP to LP conversion (5.2.4 of AMR-WB) More... | |
void | ff_acelp_lp_decode (int16_t *lp_1st, int16_t *lp_2nd, const int16_t *lsp_2nd, const int16_t *lsp_prev, int lp_order) |
Interpolate LSP for the first subframe and convert LSP -> LP for both subframes (3.2.5 and 3.2.6 of G.729) More... | |
void | ff_lsp2polyf (const double *lsp, double *f, int lp_half_order) |
Compute the Pa / (1 + z(-1)) or Qa / (1 - z(-1)) coefficients needed for LSP to LPC conversion. More... | |
void | ff_acelp_lspd2lpc (const double *lsp, float *lpc, int lp_half_order) |
Reconstruct LPC coefficients from the line spectral pair frequencies. More... | |
void | ff_sort_nearly_sorted_floats (float *vals, int len) |
Sort values in ascending order. More... | |
Variables | |
static const int16_t | tab_cos [65] |
void ff_acelp_reorder_lsf | ( | int16_t * | lsfq, |
int | lsfq_min_distance, | ||
int | lsfq_min, | ||
int | lsfq_max, | ||
int | lp_order | ||
) |
(I.F) means fixed-point value with F fractional and I integer bits
ensure a minimum distance between LSFs
[in,out] | lsfq | LSF to check and adjust |
lsfq_min_distance | minimum distance between LSFs | |
lsfq_min | minimum allowed LSF value | |
lsfq_max | maximum allowed LSF value | |
lp_order | LP filter order |
Definition at line 33 of file lsp.c.
Referenced by lsf_decode().
void ff_set_min_dist_lsf | ( | float * | lsf, |
double | min_spacing, | ||
int | size | ||
) |
Adjust the quantized LSFs so they are increasing and not too close.
This step is not mentioned in the AMR spec but is in the reference C decoder. Omitting this step creates audible distortion on the sinusoidal sweep test vectors in 3GPP TS 26.074.
[in,out] | lsf | LSFs in Hertz |
min_spacing | minimum distance between two consecutive lsf values | |
size | size of the lsf vector |
Definition at line 51 of file lsp.c.
Referenced by amrwb_decode_frame(), ff_sipr_decode_frame_16k(), lsf2lsp_3(), lsf2lsp_for_mode12k2(), and lsf_decode_fp().
|
static |
Definition at line 73 of file lsp.c.
Referenced by ff_acelp_lsf2lsp().
void ff_acelp_lsf2lsp | ( | int16_t * | lsp, |
const int16_t * | lsf, | ||
int | lp_order | ||
) |
Convert LSF to LSP.
[out] | lsp | LSP coefficients (-0x8000 <= (0.15) < 0x8000) |
lsf | normalized LSF coefficients (0 <= (2.13) < 0x2000 * PI) | |
lp_order | LP filter order |
Definition at line 83 of file lsp.c.
Referenced by decode_frame().
void ff_acelp_lsf2lspd | ( | double * | lsp, |
const float * | lsf, | ||
int | lp_order | ||
) |
Floating point version of ff_acelp_lsf2lsp()
Definition at line 93 of file lsp.c.
Referenced by amrwb_decode_frame(), decode_predictor_coeffs(), hb_synthesis(), lsf2lsp_3(), and lsf2lsp_for_mode12k2().
decodes polynomial coefficients from LSP
[out] | f | decoded polynomial coefficients (-0x20000000 <= (3.22) <= 0x1fffffff) |
lsp | LSP coefficients (-0x8000 <= (0.15) <= 0x7fff) |
Definition at line 106 of file lsp.c.
Referenced by ff_acelp_lsp2lpc().
void ff_acelp_lsp2lpc | ( | int16_t * | lp, |
const int16_t * | lsp, | ||
int | lp_half_order | ||
) |
LSP to LP conversion (3.2.6 of G.729)
[out] | lp | decoded LP coefficients (-0x8000 <= (3.12) < 0x8000) |
lsp | LSP coefficients (-0x8000 <= (0.15) < 0x8000) | |
lp_half_order | LP filter order, divided by 2 |
Definition at line 123 of file lsp.c.
Referenced by ff_acelp_lp_decode().
void ff_amrwb_lsp2lpc | ( | const double * | lsp, |
float * | lp, | ||
int | lp_order | ||
) |
LSP to LP conversion (5.2.4 of AMR-WB)
Definition at line 145 of file lsp.c.
Referenced by amrwb_decode_frame(), hb_synthesis(), and sipr_decode_lp().
void ff_acelp_lp_decode | ( | int16_t * | lp_1st, |
int16_t * | lp_2nd, | ||
const int16_t * | lsp_2nd, | ||
const int16_t * | lsp_prev, | ||
int | lp_order | ||
) |
Interpolate LSP for the first subframe and convert LSP -> LP for both subframes (3.2.5 and 3.2.6 of G.729)
[out] | lp_1st | decoded LP coefficients for first subframe (-0x8000 <= (3.12) < 0x8000) |
[out] | lp_2nd | decoded LP coefficients for second subframe (-0x8000 <= (3.12) < 0x8000) |
lsp_2nd | LSP coefficients of the second subframe (-0x8000 <= (0.15) < 0x8000) | |
lsp_prev | LSP coefficients from the second subframe of the previous frame (-0x8000 <= (0.15) < 0x8000) | |
lp_order | LP filter order |
Definition at line 171 of file lsp.c.
Referenced by decode_frame().
void ff_lsp2polyf | ( | const double * | lsp, |
double * | f, | ||
int | lp_half_order | ||
) |
Compute the Pa / (1 + z(-1)) or Qa / (1 - z(-1)) coefficients needed for LSP to LPC conversion.
We only need to calculate the 6 first elements of the polynomial.
lsp | line spectral pairs in cosine domain | |
[out] | f | polynomial input/output as a vector |
TIA/EIA/IS-733 2.4.3.3.5-1/2
Definition at line 191 of file lsp.c.
Referenced by ff_acelp_lspd2lpc(), and ff_amrwb_lsp2lpc().
void ff_acelp_lspd2lpc | ( | const double * | lsp, |
float * | lpc, | ||
int | lp_half_order | ||
) |
Reconstruct LPC coefficients from the line spectral pair frequencies.
lsp | line spectral pairs in cosine domain |
lpc | linear predictive coding coefficients |
lp_half_order | half the number of the amount of LPCs to be reconstructed, need to be smaller or equal to MAX_LP_HALF_ORDER |
TIA/EIA/IS-733 2.4.3.3.5
Definition at line 209 of file lsp.c.
Referenced by acelp_lp_decodef(), amrnb_decode_frame(), lspf2lpc(), synth_block(), and synth_frame().
void ff_sort_nearly_sorted_floats | ( | float * | vals, |
int | len | ||
) |
Sort values in ascending order.
Definition at line 228 of file lsp.c.
Referenced by decode_lsp(), and lsf_decode_fp().
|
static |
Definition at line 61 of file lsp.c.
Referenced by ff_cos().