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bluedroid/encoder: delete commented sbc scramble code

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Matthias Ringwald 2023-11-27 17:25:01 +01:00
parent 2936a8054e
commit ced70f9bfe
1 changed files with 0 additions and 88 deletions
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88
3rd-party/bluedroid/encoder/srce/sbc_encoder.c vendored
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@ -28,86 +28,6 @@
SINT16 EncMaxShiftCounter; SINT16 EncMaxShiftCounter;
/*************************************************************************************************
* SBC encoder scramble code
* Purpose: to tie the SBC code with BTE/mobile stack code,
* especially for the case when the SBC is ported into a third-party Multimedia chip
*
* Algorithm:
* init process: all counters reset to 0,
* calculate base_index: (6 + s16NumOfChannels*s16NumOfSubBands/2)
* scramble side: the init process happens every time SBC_Encoder_Init() is called.
* descramble side: it would be nice to know if he "init" process has happened.
* alter the SBC SYNC word 0x9C (1001 1100) to 0x8C (1000 1100).
*
* scramble process:
* The CRC byte:
* Every SBC frame has a frame header.
* The 1st byte is the sync word and the following 2 bytes are about the stream format.
* They are supposed to be "constant" within a "song"
* The 4th byte is the CRC byte. The CRC byte is bound to be random.
* Derive 2 items from the CRC byte; one is the "use" bit, the other is the "index".
*
* SBC keeps 2 sets of "use" & "index"; derived the current and the previous frame.
*
* The "use" bit is any bit in SBC_PRTC_USE_MASK is set.
* If set, SBC uses the "index" from the current frame.
* If not set, SBC uses the "index" from the previous frame or 0.
*
* index = (CRC & 0x3) + ((CRC & 0x30) >> 2) // 8 is the max index
*
* if(index > 0)
* {
* p = &u8frame[base_index];
* if((index&1)&&(u16PacketLength > (base_index+index*2)))
* {
* // odd index: swap 2 bytes
* tmp = p[index];
* p[index] = p[index*2];
* p[index*2] = tmp;
* }
* else
* {
* // even index: shift by 3
* tmp = (p[index] >> 5) + (p[index] << 3);
* p[index] = tmp;
* }
* }
* //else index is 0. The frame stays unaltered
*
*/
#define SBC_PRTC_CRC_IDX 3
#define SBC_PRTC_USE_MASK 0x64
#define SBC_PRTC_SYNC_MASK 0x10
#define SBC_PRTC_CIDX 0
#define SBC_PRTC_LIDX 1
typedef struct
{
UINT8 use;
UINT8 idx;
} tSBC_FR_CB;
typedef struct
{
tSBC_FR_CB fr[2];
UINT8 init;
UINT8 index;
UINT8 base;
} tSBC_PRTC_CB;
tSBC_PRTC_CB sbc_prtc_cb;
#define SBC_PRTC_IDX(sc) (((sc) & 0x3) + (((sc) & 0x30) >> 2))
#define SBC_PRTC_CHK_INIT(ar) {if(sbc_prtc_cb.init == 0){sbc_prtc_cb.init=1; ar[0] &= ~SBC_PRTC_SYNC_MASK;}}
#define SBC_PRTC_C2L() {p_last=&sbc_prtc_cb.fr[SBC_PRTC_LIDX]; p_cur=&sbc_prtc_cb.fr[SBC_PRTC_CIDX]; \
p_last->idx = p_cur->idx; p_last->use = p_cur->use;}
#define SBC_PRTC_GETC(ar) {p_cur->use = ar[SBC_PRTC_CRC_IDX] & SBC_PRTC_USE_MASK; \
p_cur->idx = SBC_PRTC_IDX(ar[SBC_PRTC_CRC_IDX]);}
#define SBC_PRTC_CHK_CRC(ar) {SBC_PRTC_C2L();SBC_PRTC_GETC(ar);sbc_prtc_cb.index = (p_cur->use)?SBC_PRTC_CIDX:SBC_PRTC_LIDX;}
#define SBC_PRTC_SCRMB(ar) {idx = sbc_prtc_cb.fr[sbc_prtc_cb.index].idx; \
if(idx > 0){if((idx&1)&&(pstrEncParams->u16PacketLength > (sbc_prtc_cb.base+(idx<<1)))) {tmp2=idx<<1; tmp=ar[idx];ar[idx]=ar[tmp2];ar[tmp2]=tmp;} \
else{tmp2=ar[idx]; tmp=(tmp2>>5)+(tmp2<<3);ar[idx]=(UINT8)tmp;}}}
#if (SBC_JOINT_STE_INCLUDED == TRUE) #if (SBC_JOINT_STE_INCLUDED == TRUE)
SINT32 s32LRDiff[SBC_MAX_NUM_OF_BLOCKS] = {0}; SINT32 s32LRDiff[SBC_MAX_NUM_OF_BLOCKS] = {0};
SINT32 s32LRSum[SBC_MAX_NUM_OF_BLOCKS] = {0}; SINT32 s32LRSum[SBC_MAX_NUM_OF_BLOCKS] = {0};
@ -129,11 +49,6 @@ void SBC_Encoder(SBC_ENC_PARAMS *pstrEncParams)
UINT32 u32CountSum,u32CountDiff; UINT32 u32CountSum,u32CountDiff;
SINT32 *pSum, *pDiff; SINT32 *pSum, *pDiff;
#endif #endif
/* BK4BTSTACK_CHANGE START */
// UINT8 *pu8;
// tSBC_FR_CB *p_cur, *p_last;
// UINT32 idx, tmp, tmp2;
/* BK4BTSTACK_CHANGE STOP */
register SINT32 s32NumOfSubBands = pstrEncParams->s16NumOfSubBands; register SINT32 s32NumOfSubBands = pstrEncParams->s16NumOfSubBands;
pstrEncParams->pu8NextPacket = pstrEncParams->pu8Packet; pstrEncParams->pu8NextPacket = pstrEncParams->pu8Packet;
@ -395,7 +310,4 @@ void SBC_Encoder_Init(SBC_ENC_PARAMS *pstrEncParams)
// pstrEncParams->u16BitRate, pstrEncParams->s16BitPool); // pstrEncParams->u16BitRate, pstrEncParams->s16BitPool);
SbcAnalysisInit(); SbcAnalysisInit();
memset(&sbc_prtc_cb, 0, sizeof(tSBC_PRTC_CB));
sbc_prtc_cb.base = 6 + (pstrEncParams->s16NumOfChannels*pstrEncParams->s16NumOfSubBands/2);
} }