diff options
Diffstat (limited to 'embdrv/sbc/encoder/srce/sbc_encoder.c')
| -rw-r--r-- | embdrv/sbc/encoder/srce/sbc_encoder.c | 401 |
1 files changed, 401 insertions, 0 deletions
diff --git a/embdrv/sbc/encoder/srce/sbc_encoder.c b/embdrv/sbc/encoder/srce/sbc_encoder.c new file mode 100644 index 0000000..f111ed0 --- /dev/null +++ b/embdrv/sbc/encoder/srce/sbc_encoder.c @@ -0,0 +1,401 @@ +/****************************************************************************** + * + * Copyright (C) 1999-2012 Broadcom Corporation + * + * Licensed under the Apache License, Version 2.0 (the "License"); + * you may not use this file except in compliance with the License. + * You may obtain a copy of the License at: + * + * http://www.apache.org/licenses/LICENSE-2.0 + * + * Unless required by applicable law or agreed to in writing, software + * distributed under the License is distributed on an "AS IS" BASIS, + * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. + * See the License for the specific language governing permissions and + * limitations under the License. + * + ******************************************************************************/ + +/****************************************************************************** + * + * contains code for encoder flow and initalization of encoder + * + ******************************************************************************/ + +#include <string.h> +#include "sbc_encoder.h" +#include "sbc_enc_func_declare.h" + +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}; +#endif + +void SBC_Encoder(SBC_ENC_PARAMS *pstrEncParams) +{ + SINT32 s32Ch; /* counter for ch*/ + SINT32 s32Sb; /* counter for sub-band*/ + UINT32 u32Count, maxBit = 0; /* loop count*/ + SINT32 s32MaxValue; /* temp variable to store max value */ + + SINT16 *ps16ScfL; + SINT32 *SbBuffer; + SINT32 s32Blk; /* counter for block*/ + SINT32 s32NumOfBlocks = pstrEncParams->s16NumOfBlocks; +#if (SBC_JOINT_STE_INCLUDED == TRUE) + SINT32 s32MaxValue2; + 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; + +#if (SBC_NO_PCM_CPY_OPTION == TRUE) + pstrEncParams->ps16NextPcmBuffer = pstrEncParams->ps16PcmBuffer; +#else + pstrEncParams->ps16NextPcmBuffer = pstrEncParams->as16PcmBuffer; +#endif + do + { + /* SBC ananlysis filter*/ + if (s32NumOfSubBands == 4) + SbcAnalysisFilter4(pstrEncParams); + else + SbcAnalysisFilter8(pstrEncParams); + + /* compute the scale factor, and save the max */ + ps16ScfL = pstrEncParams->as16ScaleFactor; + s32Ch=pstrEncParams->s16NumOfChannels*s32NumOfSubBands; + + pstrEncParams->ps16NextPcmBuffer+=s32Ch*s32NumOfBlocks; /* in case of multible sbc frame to encode update the pcm pointer */ + + for (s32Sb=0; s32Sb<s32Ch; s32Sb++) + { + SbBuffer=pstrEncParams->s32SbBuffer+s32Sb; + s32MaxValue=0; + for (s32Blk=s32NumOfBlocks;s32Blk>0;s32Blk--) + { + if (s32MaxValue<abs32(*SbBuffer)) + s32MaxValue=abs32(*SbBuffer); + SbBuffer+=s32Ch; + } + + u32Count = (s32MaxValue > 0x800000) ? 9 : 0; + + for ( ; u32Count < 15; u32Count++) + { + if (s32MaxValue <= (SINT32)(0x8000 << u32Count)) + break; + } + *ps16ScfL++ = (SINT16)u32Count; + + if (u32Count > maxBit) + maxBit = u32Count; + } + /* In case of JS processing,check whether to use JS */ +#if (SBC_JOINT_STE_INCLUDED == TRUE) + if (pstrEncParams->s16ChannelMode == SBC_JOINT_STEREO) + { + /* Calculate sum and differance scale factors for making JS decision */ + ps16ScfL = pstrEncParams->as16ScaleFactor ; + /* calculate the scale factor of Joint stereo max sum and diff */ + for (s32Sb = 0; s32Sb < s32NumOfSubBands-1; s32Sb++) + { + SbBuffer=pstrEncParams->s32SbBuffer+s32Sb; + s32MaxValue2=0; + s32MaxValue=0; + pSum = s32LRSum; + pDiff = s32LRDiff; + for (s32Blk=0;s32Blk<s32NumOfBlocks;s32Blk++) + { + *pSum=(*SbBuffer+*(SbBuffer+s32NumOfSubBands))>>1; + if (abs32(*pSum)>s32MaxValue) + s32MaxValue=abs32(*pSum); + pSum++; + *pDiff=(*SbBuffer-*(SbBuffer+s32NumOfSubBands))>>1; + if (abs32(*pDiff)>s32MaxValue2) + s32MaxValue2=abs32(*pDiff); + pDiff++; + SbBuffer+=s32Ch; + } + u32Count = (s32MaxValue > 0x800000) ? 9 : 0; + for ( ; u32Count < 15; u32Count++) + { + if (s32MaxValue <= (SINT32)(0x8000 << u32Count)) + break; + } + u32CountSum=u32Count; + u32Count = (s32MaxValue2 > 0x800000) ? 9 : 0; + for ( ; u32Count < 15; u32Count++) + { + if (s32MaxValue2 <= (SINT32)(0x8000 << u32Count)) + break; + } + u32CountDiff=u32Count; + if ( (*ps16ScfL + *(ps16ScfL+s32NumOfSubBands)) > (SINT16)(u32CountSum + u32CountDiff) ) + { + + if (u32CountSum > maxBit) + maxBit = u32CountSum; + + if (u32CountDiff > maxBit) + maxBit = u32CountDiff; + + *ps16ScfL = (SINT16)u32CountSum; + *(ps16ScfL+s32NumOfSubBands) = (SINT16)u32CountDiff; + + SbBuffer=pstrEncParams->s32SbBuffer+s32Sb; + pSum = s32LRSum; + pDiff = s32LRDiff; + + for (s32Blk = 0; s32Blk < s32NumOfBlocks; s32Blk++) + { + *SbBuffer = *pSum; + *(SbBuffer+s32NumOfSubBands) = *pDiff; + + SbBuffer += s32NumOfSubBands<<1; + pSum++; + pDiff++; + } + + pstrEncParams->as16Join[s32Sb] = 1; + } + else + { + pstrEncParams->as16Join[s32Sb] = 0; + } + ps16ScfL++; + } + pstrEncParams->as16Join[s32Sb] = 0; + } +#endif + + pstrEncParams->s16MaxBitNeed = (SINT16)maxBit; + + /* bit allocation */ + if ((pstrEncParams->s16ChannelMode == SBC_STEREO) || (pstrEncParams->s16ChannelMode == SBC_JOINT_STEREO)) + sbc_enc_bit_alloc_ste(pstrEncParams); + else + 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 */ + +} + +/**************************************************************************** +* InitSbcAnalysisFilt - Initalizes the input data to 0 +* +* RETURNS : N/A +*/ +void SBC_Encoder_Init(SBC_ENC_PARAMS *pstrEncParams) +{ + UINT16 s16SamplingFreq; /*temp variable to store smpling freq*/ + SINT16 s16Bitpool; /*to store bit pool value*/ + SINT16 s16BitRate; /*to store bitrate*/ + SINT16 s16FrameLen; /*to store frame length*/ + UINT16 HeaderParams; + + pstrEncParams->u8NumPacketToEncode = 1; /* default is one for retrocompatibility purpose */ + + /* Required number of channels */ + if (pstrEncParams->s16ChannelMode == SBC_MONO) + pstrEncParams->s16NumOfChannels = 1; + else + pstrEncParams->s16NumOfChannels = 2; + + /* Bit pool calculation */ + if (pstrEncParams->s16SamplingFreq == SBC_sf16000) + s16SamplingFreq = 16000; + else if (pstrEncParams->s16SamplingFreq == SBC_sf32000) + s16SamplingFreq = 32000; + else if (pstrEncParams->s16SamplingFreq == SBC_sf44100) + s16SamplingFreq = 44100; + else + s16SamplingFreq = 48000; + + if ( (pstrEncParams->s16ChannelMode == SBC_JOINT_STEREO) + || (pstrEncParams->s16ChannelMode == SBC_STEREO) ) + { + s16Bitpool = (SINT16)( (pstrEncParams->u16BitRate * + pstrEncParams->s16NumOfSubBands * 1000 / s16SamplingFreq) + -( (32 + (4 * pstrEncParams->s16NumOfSubBands * + pstrEncParams->s16NumOfChannels) + + ( (pstrEncParams->s16ChannelMode - 2) * + pstrEncParams->s16NumOfSubBands ) ) + / pstrEncParams->s16NumOfBlocks) ); + + s16FrameLen = 4 + (4*pstrEncParams->s16NumOfSubBands* + pstrEncParams->s16NumOfChannels)/8 + + ( ((pstrEncParams->s16ChannelMode - 2) * + pstrEncParams->s16NumOfSubBands) + + (pstrEncParams->s16NumOfBlocks * s16Bitpool) ) / 8; + + s16BitRate = (8 * s16FrameLen * s16SamplingFreq) + / (pstrEncParams->s16NumOfSubBands * + pstrEncParams->s16NumOfBlocks * 1000); + + if (s16BitRate > pstrEncParams->u16BitRate) + s16Bitpool--; + + if(pstrEncParams->s16NumOfSubBands == 8) + pstrEncParams->s16BitPool = (s16Bitpool > 255) ? 255 : s16Bitpool; + else + pstrEncParams->s16BitPool = (s16Bitpool > 128) ? 128 : s16Bitpool; + } + else + { + s16Bitpool = (SINT16)( ((pstrEncParams->s16NumOfSubBands * + pstrEncParams->u16BitRate * 1000) + / (s16SamplingFreq * pstrEncParams->s16NumOfChannels)) + -( ( (32 / pstrEncParams->s16NumOfChannels) + + (4 * pstrEncParams->s16NumOfSubBands) ) + / pstrEncParams->s16NumOfBlocks ) ); + + pstrEncParams->s16BitPool = (s16Bitpool > + (16 * pstrEncParams->s16NumOfSubBands)) + ? (16*pstrEncParams->s16NumOfSubBands) : s16Bitpool; + } + + if (pstrEncParams->s16BitPool < 0) + pstrEncParams->s16BitPool = 0; + /* sampling freq */ + HeaderParams = ((pstrEncParams->s16SamplingFreq & 3)<< 6); + + /* number of blocks*/ + HeaderParams |= (((pstrEncParams->s16NumOfBlocks -4) & 12) << 2); + + /* channel mode: mono, dual...*/ + HeaderParams |= ((pstrEncParams->s16ChannelMode & 3)<< 2); + + /* Loudness or SNR */ + HeaderParams |= ((pstrEncParams->s16AllocationMethod & 1)<< 1); + HeaderParams |= ((pstrEncParams->s16NumOfSubBands >> 3) & 1); /*4 or 8*/ + pstrEncParams->FrameHeader=HeaderParams; + + if (pstrEncParams->s16NumOfSubBands==4) + { + if (pstrEncParams->s16NumOfChannels==1) + EncMaxShiftCounter=((ENC_VX_BUFFER_SIZE-4*10)>>2)<<2; + else + EncMaxShiftCounter=((ENC_VX_BUFFER_SIZE-4*10*2)>>3)<<2; + } + else + { + if (pstrEncParams->s16NumOfChannels==1) + EncMaxShiftCounter=((ENC_VX_BUFFER_SIZE-8*10)>>3)<<3; + else + EncMaxShiftCounter=((ENC_VX_BUFFER_SIZE-8*10*2)>>4)<<3; + } + + APPL_TRACE_EVENT2("SBC_Encoder_Init : bitrate %d, bitpool %d", + pstrEncParams->u16BitRate, pstrEncParams->s16BitPool); + + SbcAnalysisInit(); + + memset(&sbc_prtc_cb, 0, sizeof(tSBC_PRTC_CB)); + sbc_prtc_cb.base = 6 + pstrEncParams->s16NumOfChannels*pstrEncParams->s16NumOfSubBands/2; +} |