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1 /******************************************************************************
2  *
3  *  Copyright (C) 1999-2012 Broadcom Corporation
4  *
5  *  Licensed under the Apache License, Version 2.0 (the "License");
6  *  you may not use this file except in compliance with the License.
7  *  You may obtain a copy of the License at:
8  *
9  *  http://www.apache.org/licenses/LICENSE-2.0
10  *
11  *  Unless required by applicable law or agreed to in writing, software
12  *  distributed under the License is distributed on an "AS IS" BASIS,
13  *  WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
14  *  See the License for the specific language governing permissions and
15  *  limitations under the License.
16  *
17  ******************************************************************************/
18 
19 /******************************************************************************
20  *
21  *  contains code for encoder flow and initalization of encoder
22  *
23  ******************************************************************************/
24 
25 #include <string.h>
26 #include "bt_target.h"
27 #include "sbc_encoder.h"
28 #include "sbc_enc_func_declare.h"
29 
30 SINT16 EncMaxShiftCounter;
31 
32 #if (SBC_JOINT_STE_INCLUDED == TRUE)
33 SINT32   s32LRDiff[SBC_MAX_NUM_OF_BLOCKS]    = {0};
34 SINT32   s32LRSum[SBC_MAX_NUM_OF_BLOCKS]     = {0};
35 #endif
36 
SBC_Encoder(SBC_ENC_PARAMS * pstrEncParams)37 void SBC_Encoder(SBC_ENC_PARAMS *pstrEncParams)
38 {
39     SINT32 s32Ch;                               /* counter for ch*/
40     SINT32 s32Sb;                               /* counter for sub-band*/
41     UINT32 u32Count, maxBit = 0;                          /* loop count*/
42     SINT32 s32MaxValue;                         /* temp variable to store max value */
43 
44     SINT16 *ps16ScfL;
45     SINT32 *SbBuffer;
46     SINT32 s32Blk;                              /* counter for block*/
47     SINT32  s32NumOfBlocks   = pstrEncParams->s16NumOfBlocks;
48 #if (SBC_JOINT_STE_INCLUDED == TRUE)
49     SINT32 s32MaxValue2;
50     UINT32 u32CountSum,u32CountDiff;
51     SINT32 *pSum, *pDiff;
52 #endif
53     UINT8  *pu8;
54     register SINT32  s32NumOfSubBands = pstrEncParams->s16NumOfSubBands;
55 
56     pstrEncParams->pu8NextPacket = pstrEncParams->pu8Packet;
57 
58 #if (SBC_NO_PCM_CPY_OPTION == TRUE)
59     pstrEncParams->ps16NextPcmBuffer = pstrEncParams->ps16PcmBuffer;
60 #else
61     pstrEncParams->ps16NextPcmBuffer  = pstrEncParams->as16PcmBuffer;
62 #endif
63     do
64     {
65         /* SBC ananlysis filter*/
66         if (s32NumOfSubBands == 4)
67             SbcAnalysisFilter4(pstrEncParams);
68         else
69             SbcAnalysisFilter8(pstrEncParams);
70 
71         /* compute the scale factor, and save the max */
72         ps16ScfL = pstrEncParams->as16ScaleFactor;
73         s32Ch=pstrEncParams->s16NumOfChannels*s32NumOfSubBands;
74 
75             pstrEncParams->ps16NextPcmBuffer+=s32Ch*s32NumOfBlocks; /* in case of multible sbc frame to encode update the pcm pointer */
76 
77         for (s32Sb=0; s32Sb<s32Ch; s32Sb++)
78         {
79             SbBuffer=pstrEncParams->s32SbBuffer+s32Sb;
80             s32MaxValue=0;
81             for (s32Blk=s32NumOfBlocks;s32Blk>0;s32Blk--)
82             {
83                 if (s32MaxValue<abs32(*SbBuffer))
84                     s32MaxValue=abs32(*SbBuffer);
85                 SbBuffer+=s32Ch;
86             }
87 
88             u32Count = (s32MaxValue > 0x800000) ? 9 : 0;
89 
90             for ( ; u32Count < 15; u32Count++)
91             {
92                 if (s32MaxValue <= (SINT32)(0x8000 << u32Count))
93                     break;
94             }
95             *ps16ScfL++ = (SINT16)u32Count;
96 
97             if (u32Count > maxBit)
98                 maxBit = u32Count;
99         }
100         /* In case of JS processing,check whether to use JS */
101 #if (SBC_JOINT_STE_INCLUDED == TRUE)
102         if (pstrEncParams->s16ChannelMode == SBC_JOINT_STEREO)
103         {
104             /* Calculate sum and differance  scale factors for making JS decision   */
105             ps16ScfL = pstrEncParams->as16ScaleFactor ;
106             /* calculate the scale factor of Joint stereo max sum and diff */
107             for (s32Sb = 0; s32Sb < s32NumOfSubBands-1; s32Sb++)
108             {
109                 SbBuffer=pstrEncParams->s32SbBuffer+s32Sb;
110                 s32MaxValue2=0;
111                 s32MaxValue=0;
112                 pSum       = s32LRSum;
113                 pDiff      = s32LRDiff;
114                 for (s32Blk=0;s32Blk<s32NumOfBlocks;s32Blk++)
115                 {
116                     *pSum=(*SbBuffer+*(SbBuffer+s32NumOfSubBands))>>1;
117                     if (abs32(*pSum)>s32MaxValue)
118                         s32MaxValue=abs32(*pSum);
119                     pSum++;
120                     *pDiff=(*SbBuffer-*(SbBuffer+s32NumOfSubBands))>>1;
121                     if (abs32(*pDiff)>s32MaxValue2)
122                         s32MaxValue2=abs32(*pDiff);
123                     pDiff++;
124                     SbBuffer+=s32Ch;
125                 }
126                 u32Count = (s32MaxValue > 0x800000) ? 9 : 0;
127                 for ( ; u32Count < 15; u32Count++)
128                 {
129                     if (s32MaxValue <= (SINT32)(0x8000 << u32Count))
130                         break;
131                 }
132                 u32CountSum=u32Count;
133                 u32Count = (s32MaxValue2 > 0x800000) ? 9 : 0;
134                 for ( ; u32Count < 15; u32Count++)
135                 {
136                     if (s32MaxValue2 <= (SINT32)(0x8000 << u32Count))
137                         break;
138                 }
139                 u32CountDiff=u32Count;
140                 if ( (*ps16ScfL + *(ps16ScfL+s32NumOfSubBands)) > (SINT16)(u32CountSum + u32CountDiff) )
141                 {
142 
143                     if (u32CountSum > maxBit)
144                         maxBit = u32CountSum;
145 
146                     if (u32CountDiff > maxBit)
147                         maxBit = u32CountDiff;
148 
149                     *ps16ScfL = (SINT16)u32CountSum;
150                     *(ps16ScfL+s32NumOfSubBands) = (SINT16)u32CountDiff;
151 
152                     SbBuffer=pstrEncParams->s32SbBuffer+s32Sb;
153                     pSum       = s32LRSum;
154                     pDiff      = s32LRDiff;
155 
156                     for (s32Blk = 0; s32Blk < s32NumOfBlocks; s32Blk++)
157                     {
158                         *SbBuffer = *pSum;
159                         *(SbBuffer+s32NumOfSubBands) = *pDiff;
160 
161                         SbBuffer += s32NumOfSubBands<<1;
162                         pSum++;
163                         pDiff++;
164                     }
165 
166                     pstrEncParams->as16Join[s32Sb] = 1;
167                 }
168                 else
169                 {
170                     pstrEncParams->as16Join[s32Sb] = 0;
171                 }
172                 ps16ScfL++;
173             }
174             pstrEncParams->as16Join[s32Sb] = 0;
175         }
176 #endif
177 
178         pstrEncParams->s16MaxBitNeed = (SINT16)maxBit;
179 
180         /* bit allocation */
181         if ((pstrEncParams->s16ChannelMode == SBC_STEREO) || (pstrEncParams->s16ChannelMode == SBC_JOINT_STEREO))
182             sbc_enc_bit_alloc_ste(pstrEncParams);
183         else
184             sbc_enc_bit_alloc_mono(pstrEncParams);
185 
186         /* save the beginning of the frame. pu8NextPacket is modified in EncPacking() */
187         pu8 = pstrEncParams->pu8NextPacket;
188         /* Quantize the encoded audio */
189         EncPacking(pstrEncParams);
190     }
191     while(--(pstrEncParams->u8NumPacketToEncode));
192 
193     pstrEncParams->u8NumPacketToEncode = 1; /* default is one for retrocompatibility purpose */
194 
195 }
196 
197 /****************************************************************************
198 * InitSbcAnalysisFilt - Initalizes the input data to 0
199 *
200 * RETURNS : N/A
201 */
SBC_Encoder_Init(SBC_ENC_PARAMS * pstrEncParams)202 void SBC_Encoder_Init(SBC_ENC_PARAMS *pstrEncParams)
203 {
204     UINT16 s16SamplingFreq; /*temp variable to store smpling freq*/
205     SINT16 s16Bitpool;      /*to store bit pool value*/
206     SINT16 s16BitRate;      /*to store bitrate*/
207     SINT16 s16FrameLen;     /*to store frame length*/
208     UINT16 HeaderParams;
209 
210     pstrEncParams->u8NumPacketToEncode = 1; /* default is one for retrocompatibility purpose */
211 
212     /* Required number of channels */
213     if (pstrEncParams->s16ChannelMode == SBC_MONO)
214         pstrEncParams->s16NumOfChannels = 1;
215     else
216         pstrEncParams->s16NumOfChannels = 2;
217 
218     /* Bit pool calculation */
219     if (pstrEncParams->s16SamplingFreq == SBC_sf16000)
220         s16SamplingFreq = 16000;
221     else if (pstrEncParams->s16SamplingFreq == SBC_sf32000)
222         s16SamplingFreq = 32000;
223     else if (pstrEncParams->s16SamplingFreq == SBC_sf44100)
224         s16SamplingFreq = 44100;
225     else
226         s16SamplingFreq = 48000;
227 
228     if ( (pstrEncParams->s16ChannelMode == SBC_JOINT_STEREO)
229         ||  (pstrEncParams->s16ChannelMode == SBC_STEREO) )
230     {
231         s16Bitpool = (SINT16)( (pstrEncParams->u16BitRate *
232             pstrEncParams->s16NumOfSubBands * 1000 / s16SamplingFreq)
233             -( (32 + (4 * pstrEncParams->s16NumOfSubBands *
234             pstrEncParams->s16NumOfChannels)
235             + ( (pstrEncParams->s16ChannelMode - 2) *
236             pstrEncParams->s16NumOfSubBands )   )
237             / pstrEncParams->s16NumOfBlocks) );
238 
239         s16FrameLen = 4 + (4*pstrEncParams->s16NumOfSubBands*
240             pstrEncParams->s16NumOfChannels)/8
241             + ( ((pstrEncParams->s16ChannelMode - 2) *
242             pstrEncParams->s16NumOfSubBands)
243             + (pstrEncParams->s16NumOfBlocks * s16Bitpool) ) / 8;
244 
245         s16BitRate = (8 * s16FrameLen * s16SamplingFreq)
246             / (pstrEncParams->s16NumOfSubBands *
247             pstrEncParams->s16NumOfBlocks * 1000);
248 
249         if (s16BitRate > pstrEncParams->u16BitRate)
250             s16Bitpool--;
251 
252         if(pstrEncParams->s16NumOfSubBands == 8)
253             pstrEncParams->s16BitPool = (s16Bitpool > 255) ? 255 : s16Bitpool;
254         else
255             pstrEncParams->s16BitPool = (s16Bitpool > 128) ? 128 : s16Bitpool;
256     }
257     else
258     {
259         s16Bitpool = (SINT16)( ((pstrEncParams->s16NumOfSubBands *
260             pstrEncParams->u16BitRate * 1000)
261             / (s16SamplingFreq * pstrEncParams->s16NumOfChannels))
262             -( ( (32 / pstrEncParams->s16NumOfChannels) +
263             (4 * pstrEncParams->s16NumOfSubBands) )
264             /   pstrEncParams->s16NumOfBlocks ) );
265 
266         pstrEncParams->s16BitPool = (s16Bitpool >
267             (16 * pstrEncParams->s16NumOfSubBands))
268             ? (16*pstrEncParams->s16NumOfSubBands) : s16Bitpool;
269     }
270 
271     if (pstrEncParams->s16BitPool < 0)
272         pstrEncParams->s16BitPool = 0;
273     /* sampling freq */
274     HeaderParams = ((pstrEncParams->s16SamplingFreq & 3)<< 6);
275 
276     /* number of blocks*/
277     HeaderParams |= (((pstrEncParams->s16NumOfBlocks -4) & 12) << 2);
278 
279     /* channel mode: mono, dual...*/
280     HeaderParams |= ((pstrEncParams->s16ChannelMode & 3)<< 2);
281 
282     /* Loudness or SNR */
283     HeaderParams |= ((pstrEncParams->s16AllocationMethod & 1)<< 1);
284     HeaderParams |= ((pstrEncParams->s16NumOfSubBands >> 3) & 1);  /*4 or 8*/
285     pstrEncParams->FrameHeader=HeaderParams;
286 
287     if (pstrEncParams->s16NumOfSubBands==4)
288     {
289         if (pstrEncParams->s16NumOfChannels==1)
290             EncMaxShiftCounter=((ENC_VX_BUFFER_SIZE-4*10)>>2)<<2;
291         else
292             EncMaxShiftCounter=((ENC_VX_BUFFER_SIZE-4*10*2)>>3)<<2;
293     }
294     else
295     {
296         if (pstrEncParams->s16NumOfChannels==1)
297             EncMaxShiftCounter=((ENC_VX_BUFFER_SIZE-8*10)>>3)<<3;
298         else
299             EncMaxShiftCounter=((ENC_VX_BUFFER_SIZE-8*10*2)>>4)<<3;
300     }
301 
302     APPL_TRACE_EVENT("SBC_Encoder_Init : bitrate %d, bitpool %d",
303             pstrEncParams->u16BitRate, pstrEncParams->s16BitPool);
304 
305     SbcAnalysisInit();
306 }
307