FreeCalypso > hg > gsm-codec-lib
view libtwamr/basic_op.h @ 581:e2d5cad04cbf
libgsmhr1 RxFE: store CN R0+LPC separately from speech
In the original GSM 06.06 code the ECU for speech mode is entirely
separate from the CN generator, maintaining separate state. (The
main intertie between them is the speech vs CN state variable,
distinguishing between speech and CN BFIs, in addition to the
CN-specific function of distinguishing between initial and update
SIDs.)
In the present RxFE implementation I initially thought that we could
use the same saved_frame buffer for both ECU and CN, overwriting
just the first 4 params (R0 and LPC) when a valid SID comes in.
However, I now realize it was a bad idea: the original code has a
corner case (long sequence of speech-mode BFIs to put the ECU in
state 6, then SID and CN-mode BFIs, then a good speech frame) that
would be broken by that buffer reuse approach. We could eliminate
this corner case by resetting the ECU state when passing through
a CN insertion period, but doing so would needlessly increase
the behavioral diffs between GSM 06.06 and our version.
Solution: use a separate CN-specific buffer for CN R0+LPC parameters,
and match the behavior of GSM 06.06 code in this regard.
author | Mychaela Falconia <falcon@freecalypso.org> |
---|---|
date | Thu, 13 Feb 2025 10:02:45 +0000 |
parents | 57b4053559ff |
children |
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/*___________________________________________________________________________ | | | Constants and Globals | |___________________________________________________________________________| */ extern __thread Flag Overflow; extern __thread Flag Carry; #define MAX_32 (Word32)0x7fffffffL #define MIN_32 (Word32)0x80000000L #define MAX_16 (Word16)0x7fff #define MIN_16 (Word16)0x8000 /*___________________________________________________________________________ | | | Prototypes for basic arithmetic operators | |___________________________________________________________________________| */ Word16 add (Word16 var1, Word16 var2); /* Short add, 1 */ Word16 sub (Word16 var1, Word16 var2); /* Short sub, 1 */ Word16 abs_s (Word16 var1); /* Short abs, 1 */ Word16 shl (Word16 var1, Word16 var2); /* Short shift left, 1 */ Word16 shr (Word16 var1, Word16 var2); /* Short shift right, 1 */ Word16 mult (Word16 var1, Word16 var2); /* Short mult, 1 */ Word32 L_mult (Word16 var1, Word16 var2); /* Long mult, 1 */ Word16 negate (Word16 var1); /* Short negate, 1 */ Word16 extract_h (Word32 L_var1); /* Extract high, 1 */ Word16 extract_l (Word32 L_var1); /* Extract low, 1 */ Word16 round (Word32 L_var1); /* Round, 1 */ Word32 L_mac (Word32 L_var3, Word16 var1, Word16 var2); /* Mac, 1 */ Word32 L_msu (Word32 L_var3, Word16 var1, Word16 var2); /* Msu, 1 */ Word32 L_macNs (Word32 L_var3, Word16 var1, Word16 var2); /* Mac without sat, 1 */ Word32 L_msuNs (Word32 L_var3, Word16 var1, Word16 var2); /* Msu without sat, 1 */ Word32 L_add (Word32 L_var1, Word32 L_var2); /* Long add, 2 */ Word32 L_sub (Word32 L_var1, Word32 L_var2); /* Long sub, 2 */ Word32 L_add_c (Word32 L_var1, Word32 L_var2); /* Long add with c, 2 */ Word32 L_sub_c (Word32 L_var1, Word32 L_var2); /* Long sub with c, 2 */ Word32 L_negate (Word32 L_var1); /* Long negate, 2 */ Word16 mult_r (Word16 var1, Word16 var2); /* Mult with round, 2 */ Word32 L_shl (Word32 L_var1, Word16 var2); /* Long shift left, 2 */ Word32 L_shr (Word32 L_var1, Word16 var2); /* Long shift right, 2*/ Word16 shr_r (Word16 var1, Word16 var2); /* Shift right with round, 2 */ Word16 mac_r (Word32 L_var3, Word16 var1, Word16 var2); /* Mac with rounding,2 */ Word16 msu_r (Word32 L_var3, Word16 var1, Word16 var2); /* Msu with rounding,2 */ Word32 L_deposit_h (Word16 var1); /* 16 bit var1 -> MSB, 2 */ Word32 L_deposit_l (Word16 var1); /* 16 bit var1 -> LSB, 2 */ Word32 L_shr_r (Word32 L_var1, Word16 var2); /* Long shift right with round, 3 */ Word32 L_abs (Word32 L_var1); /* Long abs, 3 */ Word32 L_sat (Word32 L_var1); /* Long saturation, 4 */ Word16 norm_s (Word16 var1); /* Short norm, 15 */ Word16 div_s (Word16 var1, Word16 var2); /* Short division, 18 */ Word16 norm_l (Word32 L_var1); /* Long norm, 30 */