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component/bt: remove SBC frame scramling

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This commit is contained in:
baohongde 2019-03-25 20:28:55 +08:00
parent fd70355d5d
commit f15323b453
5 changed files with 1 additions and 285 deletions
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3
components/bt/bluedroid/btc/profile/std/a2dp/btc_a2dp_source.c
View file

@ -1375,8 +1375,7 @@ static void btc_media_aa_prep_sbc_2_send(UINT8 nb_frame)
if (btc_media_aa_read_feeding()) {
/* SBC encode and descramble frame */
SBC_Encoder(&(btc_sbc_encoder));
A2D_SbcChkFrInit(btc_sbc_encoder.pu8Packet);
A2D_SbcDescramble(btc_sbc_encoder.pu8Packet, btc_sbc_encoder.u16PacketLength);
/* Update SBC frame length */
p_buf->len += btc_sbc_encoder.u16PacketLength;
nb_frame--;

97
components/bt/bluedroid/external/sbc/encoder/srce/sbc_encoder.c vendored
View file

@ -31,84 +31,6 @@
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)
SINT32 s32LRDiff[SBC_MAX_NUM_OF_BLOCKS] = {0};
SINT32 s32LRSum[SBC_MAX_NUM_OF_BLOCKS] = {0};
@ -130,9 +52,6 @@ void SBC_Encoder(SBC_ENC_PARAMS *pstrEncParams)
UINT32 u32CountSum, u32CountDiff;
SINT32 *pSum, *pDiff;
#endif
UINT8 *pu8;
tSBC_FR_CB *p_cur, *p_last;
UINT32 idx, tmp, tmp2;
register SINT32 s32NumOfSubBands = pstrEncParams->s16NumOfSubBands;
pstrEncParams->pu8NextPacket = pstrEncParams->pu8Packet;
@ -263,22 +182,9 @@ void SBC_Encoder(SBC_ENC_PARAMS *pstrEncParams)
sbc_enc_bit_alloc_mono(pstrEncParams);
}
/* save the beginning of the frame. pu8NextPacket is modified in EncPacking() */
pu8 = pstrEncParams->pu8NextPacket;
/* Quantize the encoded audio */
EncPacking(pstrEncParams);
/* scramble the code */
SBC_PRTC_CHK_INIT(pu8);
SBC_PRTC_CHK_CRC(pu8);
#if 0
if (pstrEncParams->u16PacketLength > ((sbc_prtc_cb.fr[sbc_prtc_cb.index].idx * 2) + sbc_prtc_cb.base)) {
printf("len: %d, idx: %d\n", pstrEncParams->u16PacketLength, sbc_prtc_cb.fr[sbc_prtc_cb.index].idx);
} else {
printf("len: %d, idx: %d!!!!\n", pstrEncParams->u16PacketLength, sbc_prtc_cb.fr[sbc_prtc_cb.index].idx);
}
#endif
SBC_PRTC_SCRMB((&pu8[sbc_prtc_cb.base]));
} while (--(pstrEncParams->u8NumPacketToEncode));
pstrEncParams->u8NumPacketToEncode = 1; /* default is one for retrocompatibility purpose */
@ -395,9 +301,6 @@ void SBC_Encoder_Init(SBC_ENC_PARAMS *pstrEncParams)
pstrEncParams->u16BitRate, pstrEncParams->s16BitPool);
SbcAnalysisInit();
memset(&sbc_prtc_cb, 0, sizeof(tSBC_PRTC_CB));
sbc_prtc_cb.base = 6 + pstrEncParams->s16NumOfChannels * pstrEncParams->s16NumOfSubBands / 2;
}
#endif /* #if (defined(SBC_ENC_INCLUDED) && SBC_ENC_INCLUDED == TRUE) */

165
components/bt/bluedroid/stack/a2dp/a2d_sbc.c
View file

@ -33,171 +33,6 @@
#if (defined(A2D_INCLUDED) && A2D_INCLUDED == TRUE)
/*************************************************************************************************
* SBC descramble 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] >> 3) + (p[index] << 5);
* p[index] = tmp;
* }
* }
* //else index is 0. The frame stays unaltered
*
*/
#define A2D_SBC_SYNC_WORD 0x9C
#define A2D_SBC_CRC_IDX 3
#define A2D_SBC_USE_MASK 0x64
#define A2D_SBC_SYNC_MASK 0x10
#define A2D_SBC_CIDX 0
#define A2D_SBC_LIDX 1
#define A2D_SBC_CH_M_BITS 0xC /* channel mode bits: 0: mono; 1 ch */
#define A2D_SBC_SUBBAND_BIT 0x1 /* num of subband bit: 0:4; 1: 8 */
#define A2D_SBC_GET_IDX(sc) (((sc) & 0x3) + (((sc) & 0x30) >> 2))
typedef struct {
UINT8 use;
UINT8 idx;
} tA2D_SBC_FR_CB;
typedef struct {
tA2D_SBC_FR_CB fr[2];
UINT8 index;
UINT8 base;
} tA2D_SBC_DS_CB;
static tA2D_SBC_DS_CB a2d_sbc_ds_cb;
/*int a2d_count = 0;*/
/******************************************************************************
**
** Function A2D_SbcChkFrInit
**
** Description check if need to init the descramble control block.
**
** Returns nothing.
******************************************************************************/
void A2D_SbcChkFrInit(UINT8 *p_pkt)
{
UINT8 fmt;
UINT8 num_chnl = 1;
UINT8 num_subband = 4;
if ((p_pkt[0] & A2D_SBC_SYNC_MASK) == 0) {
a2d_cb.use_desc = TRUE;
fmt = p_pkt[1];
p_pkt[0] |= A2D_SBC_SYNC_MASK;
memset(&a2d_sbc_ds_cb, 0, sizeof(tA2D_SBC_DS_CB));
if (fmt & A2D_SBC_CH_M_BITS) {
num_chnl = 2;
}
if (fmt & A2D_SBC_SUBBAND_BIT) {
num_subband = 8;
}
a2d_sbc_ds_cb.base = 6 + num_chnl * num_subband / 2;
/*printf("base: %d\n", a2d_sbc_ds_cb.base);
a2d_count = 0;*/
}
}
/******************************************************************************
**
** Function A2D_SbcDescramble
**
** Description descramble the packet.
**
** Returns nothing.
******************************************************************************/
void A2D_SbcDescramble(UINT8 *p_pkt, UINT16 len)
{
tA2D_SBC_FR_CB *p_cur, *p_last;
UINT32 idx, tmp, tmp2;
if (a2d_cb.use_desc) {
/* c2l */
p_last = &a2d_sbc_ds_cb.fr[A2D_SBC_LIDX];
p_cur = &a2d_sbc_ds_cb.fr[A2D_SBC_CIDX];
p_last->idx = p_cur->idx;
p_last->use = p_cur->use;
/* getc */
p_cur->use = p_pkt[A2D_SBC_CRC_IDX] & A2D_SBC_USE_MASK;
p_cur->idx = A2D_SBC_GET_IDX(p_pkt[A2D_SBC_CRC_IDX]);
a2d_sbc_ds_cb.index = (p_cur->use) ? A2D_SBC_CIDX : A2D_SBC_LIDX;
/*
printf("%05d: ar[%02d]: x%02x, msk: x%02x, use: %s, idx: %02d, ",
a2d_count++,
A2D_SBC_CRC_IDX, p_pkt[A2D_SBC_CRC_IDX], A2D_SBC_USE_MASK,
(p_cur->use)?"cur":"lst", p_cur->idx);
*/
/* descramble */
idx = a2d_sbc_ds_cb.fr[a2d_sbc_ds_cb.index].idx;
if (idx > 0) {
p_pkt = &p_pkt[a2d_sbc_ds_cb.base];
if ((idx & 1) && (len > (a2d_sbc_ds_cb.base + (idx << 1)))) {
tmp2 = (idx << 1);
tmp = p_pkt[idx];
p_pkt[idx] = p_pkt[tmp2];
p_pkt[tmp2] = tmp;
/*
printf("tmp2: %02d, len: %d, idx: %d\n",
tmp2, len, a2d_sbc_ds_cb.fr[a2d_sbc_ds_cb.index].idx);
*/
} else {
tmp2 = p_pkt[idx];
tmp = (tmp2 >> 3) + (tmp2 << 5);
p_pkt[idx] = (UINT8)tmp;
/*
printf("tmp: x%02x, len: %d, idx: %d(cmp:%d)\n",
(UINT8)tmp2, len, a2d_sbc_ds_cb.fr[a2d_sbc_ds_cb.index].idx,
(a2d_sbc_ds_cb.base+(idx<<1)));
*/
}
}
/*
else
{
printf("!!!!\n");
}
*/
}
}
/******************************************************************************
**
** Function A2D_BldSbcInfo

1
components/bt/bluedroid/stack/a2dp/include/a2d_int.h
View file

@ -51,7 +51,6 @@ typedef struct {
typedef struct {
tA2D_FIND_CB find; /* find service control block */
UINT8 trace_level;
BOOLEAN use_desc;
UINT16 avdt_sdp_ver; /* AVDTP version */
} tA2D_CB;

20
components/bt/bluedroid/stack/include/stack/a2d_sbc.h
View file

@ -92,26 +92,6 @@ typedef struct {
extern "C"
{
#endif
/******************************************************************************
**
** Function A2D_SbcChkFrInit
**
** Description check if need to init the descramble control block.
**
** Returns nothing.
******************************************************************************/
extern void A2D_SbcChkFrInit(UINT8 *p_pkt);
/******************************************************************************
**
** Function A2D_SbcDescramble
**
** Description descramble the packet.
**
** Returns nothing.
******************************************************************************/
extern void A2D_SbcDescramble(UINT8 *p_pkt, UINT16 len);
/******************************************************************************
**
** Function A2D_BldSbcInfo