1 /* ------------------------------------------------------------------
2  * Copyright (C) 1998-2009 PacketVideo
3  *
4  * Licensed under the Apache License, Version 2.0 (the "License");
5  * you may not use this file except in compliance with the License.
6  * You may obtain a copy of the License at
7  *
8  *      http://www.apache.org/licenses/LICENSE-2.0
9  *
10  * Unless required by applicable law or agreed to in writing, software
11  * distributed under the License is distributed on an "AS IS" BASIS,
12  * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either
13  * express or implied.
14  * See the License for the specific language governing permissions
15  * and limitations under the License.
16  * -------------------------------------------------------------------
17  */
18 #include "mp4def.h"
19 #include "mp4lib_int.h"
20 #include "rate_control.h"
21 #include "mp4enc_lib.h"
22 #include "bitstream_io.h"
23 #include "m4venc_oscl.h"
24 
25 void targetBitCalculation(void *input);
26 void calculateQuantizer_Multipass(void *video);
27 void updateRateControl(rateControl *rc, VideoEncData *video);
28 void updateRC_PostProc(rateControl *rc, VideoEncData *video);
29 
30 /***************************************************************************
31 **************  RC APIs to core encoding modules  *******************
32 
33 PV_STATUS RC_Initialize(void *video);
34 PV_STATUS RC_Cleanup(rateControl *rc[],Int numLayers);
35 PV_STATUS RC_VopQPSetting(VideoEncData *video,rateControl *rc[]);
36 PV_STATUS RC_VopUpdateStat(VideoEncData *video,rateControl *rc[]);
37 PV_STATUS RC_UpdateBuffer(VideoEncData *video, Int currLayer, Int num_skip);
38 Int       RC_GetSkipNextFrame(VideoEncData *video,Int currLayer);
39 void      RC_ResetSkipNextFrame(void *video,Int currLayer);
40 
41 PV_STATUS RC_UpdateBXRCParams(void *input);  Parameters update for target bitrate or framerate change
42 
43 ****************************************************************************/
44 
45 
46 /************************************************************************/
47 /************ API part **************************************************/
48 /* must be called before each sequence*/
49 
RC_Initialize(void * input)50 PV_STATUS RC_Initialize(void *input)
51 {
52     VideoEncData *video = (VideoEncData *) input;
53     VideoEncParams *encParams = video->encParams;
54     rateControl **rc = video->rc;
55     Int numLayers = encParams->nLayers;
56     Int *LayerBitRate = encParams->LayerBitRate;
57     float *LayerFrameRate = encParams->LayerFrameRate;
58     MultiPass **pMP = video->pMP;
59 
60     Int n;
61 
62     for (n = 0; n < numLayers; n++)
63     {
64         /* rate control */
65         rc[n]->fine_frame_skip = encParams->FineFrameSkip_Enabled;
66         rc[n]->no_frame_skip = encParams->NoFrameSkip_Enabled;
67         rc[n]->no_pre_skip = encParams->NoPreSkip_Enabled;
68         rc[n]->skip_next_frame = 0; /* must be initialized */
69 
70         //rc[n]->TMN_TH = (Int)((float)LayerBitRate[n]/LayerFrameRate[n]);
71         rc[n]->Bs = video->encParams->BufferSize[n];
72         rc[n]->TMN_W = 0;
73         rc[n]->VBV_fullness = (Int)(rc[n]->Bs * 0.5); /* rc[n]->Bs */
74         rc[n]->encoded_frames = 0;
75         rc[n]->framerate = LayerFrameRate[n];
76         if (n == 0)
77         {
78             rc[n]->TMN_TH = (Int)((float)LayerBitRate[n] / LayerFrameRate[n]);
79             rc[n]->bitrate = LayerBitRate[n];
80             rc[n]->framerate = LayerFrameRate[n];
81 
82             // For h263 or short header mode, the bit variation is within (-2*Rmax*1001/3000, 2*Rmax*1001/3000)
83             if (video->encParams->H263_Enabled)
84             {
85                 rc[n]->max_BitVariance_num = (Int)((rc[n]->Bs - video->encParams->maxFrameSize) / 2 / (rc[n]->bitrate / rc[n]->framerate / 10.0)) - 5;
86                 if (rc[n]->max_BitVariance_num < 0) rc[n]->max_BitVariance_num += 5;
87             }
88             else   // MPEG-4 normal modes
89             {
90                 rc[n]->max_BitVariance_num = (Int)((float)(rc[n]->Bs - rc[n]->VBV_fullness) / ((float)LayerBitRate[n] / LayerFrameRate[n] / 10.0)) - 5;
91                 if (rc[n]->max_BitVariance_num < 0) rc[n]->max_BitVariance_num += 5;
92             }
93         }
94         else
95         {
96             if (LayerFrameRate[n] - LayerFrameRate[n-1] > 0) /*  7/31/03 */
97             {
98                 rc[n]->TMN_TH = (Int)((float)(LayerBitRate[n] - LayerBitRate[n-1]) / (LayerFrameRate[n] - LayerFrameRate[n-1]));
99                 rc[n]->max_BitVariance_num = (Int)((float)(rc[n]->Bs - rc[n]->VBV_fullness) * 10 / ((float)rc[n]->TMN_TH)) - 5;
100                 if (rc[n]->max_BitVariance_num < 0) rc[n]->max_BitVariance_num += 5;
101             }
102             else   /*  7/31/03 */
103             {
104                 rc[n]->TMN_TH = 1 << 30;
105                 rc[n]->max_BitVariance_num = 0;
106             }
107             rc[n]->bitrate = LayerBitRate[n] - LayerBitRate[n-1];
108             rc[n]->framerate = LayerFrameRate[n] - LayerFrameRate[n-1];
109         }
110 
111         // Set the initial buffer fullness
112         if (1) //!video->encParams->H263_Enabled)  { // MPEG-4
113         {
114             /* According to the spec, the initial buffer fullness needs to be set to 1/3 */
115             rc[n]->VBV_fullness = (Int)(rc[n]->Bs / 3.0 - rc[n]->Bs / 2.0); /* the buffer range is [-Bs/2, Bs/2] */
116             pMP[n]->counter_BTsrc = (Int)((rc[n]->Bs / 2.0 - rc[n]->Bs / 3.0) / (rc[n]->bitrate / rc[n]->framerate / 10.0));
117             rc[n]->TMN_W = (Int)(rc[n]->VBV_fullness + pMP[n]->counter_BTsrc * (rc[n]->bitrate / rc[n]->framerate / 10.0));
118 
119             rc[n]->low_bound = -rc[n]->Bs / 2;
120             rc[n]-> VBV_fullness_offset = 0;
121         }
122         else   /* this part doesn't work in some cases, the low_bound is too high, Jan 4,2006 */
123         {
124             rc[n]->VBV_fullness =  rc[n]->Bs - (Int)(video->encParams->VBV_delay * rc[n]->bitrate);
125             if (rc[n]->VBV_fullness < 0) rc[n]->VBV_fullness = 0;
126             //rc[n]->VBV_fullness = (rc[n]->Bs-video->encParams->maxFrameSize)/2 + video->encParams->maxFrameSize;
127 
128             rc[n]->VBV_fullness -= rc[n]->Bs / 2; /* the buffer range is [-Bs/2, Bs/2] */
129             rc[n]->low_bound = -rc[n]->Bs / 2 + video->encParams->maxFrameSize;  /*  too high */
130             rc[n]->VBV_fullness_offset = video->encParams->maxFrameSize / 2; /*  don't understand the meaning of this */
131             pMP[n]->counter_BTdst = pMP[n]->counter_BTsrc = 0;
132 
133         }
134 
135         /* Setting the bitrate and framerate */
136         pMP[n]->bitrate = rc[n]->bitrate;
137         pMP[n]->framerate = rc[n]->framerate;
138         pMP[n]->target_bits_per_frame = pMP[n]->bitrate / pMP[n]->framerate;
139 
140     }
141 
142     return PV_SUCCESS;
143 }
144 
145 
146 /* ======================================================================== */
147 /*  Function : RC_Cleanup                                                   */
148 /*  Date     : 12/20/2000                                                   */
149 /*  Purpose  : free Rate Control memory                                     */
150 /*  In/out   :                                                              */
151 /*  Return   :                                                              */
152 /*  Modified :                                                              */
153 /* ======================================================================== */
154 
155 
RC_Cleanup(rateControl * rc[],Int numLayers)156 PV_STATUS RC_Cleanup(rateControl *rc[], Int numLayers)
157 {
158     OSCL_UNUSED_ARG(rc);
159     OSCL_UNUSED_ARG(numLayers);
160 
161     return PV_SUCCESS;
162 }
163 
164 
165 
166 /* ======================================================================== */
167 /*  Function : RC_VopQPSetting                                              */
168 /*  Date     : 4/11/2001                                                    */
169 /*  Purpose  : Reset rate control before coding VOP, moved from vop.c       */
170 /*              Compute QP for the whole VOP and initialize MB-based RC
171                 reset QPMB[], currVop->quantizer, rc->Ec, video->header_bits */
172 /* to          In order to  work RC_VopQPSetting has to do the followings
173                 1. Set video->QPMB of all macroblocks.
174                 2. Set currVop->quantizer
175                 3. Reset video->header_bits to zero.
176                 4. Initialize internal RC parameters for Vop cooding        */
177 /*  In/out   :                                                              */
178 /*  Return   : PV_STATUS                                                    */
179 /*  Modified :                                                              */
180 /* ======================================================================== */
181 /* To be moved to rate_control.c and separate between BX_RC and ANNEX_L     */
182 
RC_VopQPSetting(VideoEncData * video,rateControl * prc[])183 PV_STATUS RC_VopQPSetting(VideoEncData *video, rateControl *prc[])
184 {
185     Int currLayer = video->currLayer;
186     Vol *currVol = video->vol[currLayer];
187     Vop *currVop = video->currVop;
188 #ifdef TEST_MBBASED_QP
189     int i;
190 #endif
191 
192     rateControl *rc = video->rc[currLayer];
193     MultiPass *pMP = video->pMP[currLayer];
194 
195     OSCL_UNUSED_ARG(prc);
196 
197     if (video->encParams->RC_Type == CONSTANT_Q)
198     {
199         M4VENC_MEMSET(video->QPMB, currVop->quantizer, sizeof(UChar)*currVol->nTotalMB);
200         return PV_SUCCESS;
201     }
202     else
203     {
204 
205         if (video->rc[currLayer]->encoded_frames == 0) /* rc[currLayer]->totalFrameNumber*/
206         {
207             M4VENC_MEMSET(video->QPMB, currVop->quantizer, sizeof(UChar)*currVol->nTotalMB);
208             video->rc[currLayer]->Qc = video->encParams->InitQuantIvop[currLayer];
209         }
210         else
211         {
212             calculateQuantizer_Multipass((void*) video);
213             currVop->quantizer = video->rc[currLayer]->Qc;
214 #ifdef TEST_MBBASED_QP
215             i = currVol->nTotalMB;  /* testing changing QP at MB level */
216             while (i)
217             {
218                 i--;
219                 video->QPMB[i] = (i & 1) ? currVop->quantizer - 1 : currVop->quantizer + 1;
220             }
221 #else
222             M4VENC_MEMSET(video->QPMB, currVop->quantizer, sizeof(UChar)*currVol->nTotalMB);
223 #endif
224         }
225 
226         video->header_bits = 0;
227     }
228 
229     /* update pMP->framePos */
230     if (++pMP->framePos == pMP->frameRange) pMP->framePos = 0;
231 
232     if (rc->T == 0)
233     {
234         pMP->counter_BTdst = (Int)(video->encParams->LayerFrameRate[video->currLayer] * 7.5 + 0.5); /* 0.75s time frame */
235         pMP->counter_BTdst = PV_MIN(pMP->counter_BTdst, (Int)(rc->max_BitVariance_num / 2 * 0.40)); /* 0.75s time frame may go beyond VBV buffer if we set the buffer size smaller than 0.75s */
236         pMP->counter_BTdst = PV_MAX(pMP->counter_BTdst, (Int)((rc->Bs / 2 - rc->VBV_fullness) * 0.30 / (rc->TMN_TH / 10.0) + 0.5)); /* At least 30% of VBV buffer size/2 */
237         pMP->counter_BTdst = PV_MIN(pMP->counter_BTdst, 20); /* Limit the target to be smaller than 3C */
238 
239         pMP->target_bits = rc->T = rc->TMN_TH = (Int)(rc->TMN_TH * (1.0 + pMP->counter_BTdst * 0.1));
240         pMP->diff_counter = pMP->counter_BTdst;
241     }
242 
243     /* collect the necessary data: target bits, actual bits, mad and QP */
244     pMP->target_bits = rc->T;
245     pMP->QP  = currVop->quantizer;
246 
247     pMP->mad = video->sumMAD / (float)currVol->nTotalMB;
248     if (pMP->mad < MAD_MIN) pMP->mad = MAD_MIN; /* MAD_MIN is defined as 1 in mp4def.h */
249 
250     pMP->bitrate = rc->bitrate; /* calculated in RCVopQPSetting */
251     pMP->framerate = rc->framerate;
252 
253     /* first pass encoding */
254     pMP->nRe_Quantized = 0;
255 
256     return  PV_SUCCESS;
257 }
258 
259 
260 /* ======================================================================== */
261 /*  Function : SaveRDSamples()                                              */
262 /*  Date     : 08/29/2001                                                   */
263 /*  History  :                                                              */
264 /*  Purpose  : Save QP, actual_bits, mad and R_D of the current iteration   */
265 /*  In/out   :                                                              */
266 /*  Return   :                                                              */
267 /*  Modified :                                                              */
268 /*                                                                          */
269 /* ======================================================================== */
270 
SaveRDSamples(MultiPass * pMP,Int counter_samples)271 Void SaveRDSamples(MultiPass *pMP, Int counter_samples)
272 {
273     /* for pMP->pRDSamples */
274     pMP->pRDSamples[pMP->framePos][counter_samples].QP    = pMP->QP;
275     pMP->pRDSamples[pMP->framePos][counter_samples].actual_bits = pMP->actual_bits;
276     pMP->pRDSamples[pMP->framePos][counter_samples].mad   = pMP->mad;
277     pMP->pRDSamples[pMP->framePos][counter_samples].R_D = (float)(pMP->actual_bits / (pMP->mad + 0.0001));
278 
279     return ;
280 }
281 /* ======================================================================== */
282 /*  Function : RC_VopUpdateStat                                             */
283 /*  Date     : 12/20/2000                                                   */
284 /*  Purpose  : Update statistics for rate control after encoding each VOP.  */
285 /*             No need to change anything in VideoEncData structure.        */
286 /*  In/out   :                                                              */
287 /*  Return   :                                                              */
288 /*  Modified :                                                              */
289 /* ======================================================================== */
290 
RC_VopUpdateStat(VideoEncData * video,rateControl * rc)291 PV_STATUS RC_VopUpdateStat(VideoEncData *video, rateControl *rc)
292 {
293     Int currLayer = video->currLayer;
294     Vol *currVol = video->vol[currLayer];
295     MultiPass *pMP = video->pMP[currLayer];
296     Int diff_BTCounter;
297 
298     switch (video->encParams->RC_Type)
299     {
300         case CONSTANT_Q:
301             break;
302 
303         case CBR_1:
304         case CBR_2:
305         case VBR_1:
306         case VBR_2:
307         case CBR_LOWDELAY:
308 
309             pMP->actual_bits = currVol->stream->byteCount << 3;
310 
311             SaveRDSamples(pMP, 0);
312 
313             pMP->encoded_frames++;
314 
315             /* for pMP->samplesPerFrame */
316             pMP->samplesPerFrame[pMP->framePos] = 0;
317 
318             pMP->sum_QP += pMP->QP;
319 
320 
321             /* update pMP->counter_BTsrc, pMP->counter_BTdst */
322             /* re-allocate the target bit again and then stop encoding */
323             diff_BTCounter = (Int)((float)(rc->TMN_TH - rc->TMN_W - pMP->actual_bits) /
324                                    (pMP->bitrate / (pMP->framerate + 0.0001) + 0.0001) / 0.1);
325             if (diff_BTCounter >= 0)
326                 pMP->counter_BTsrc += diff_BTCounter; /* pMP->actual_bits is smaller */
327             else
328                 pMP->counter_BTdst -= diff_BTCounter; /* pMP->actual_bits is bigger */
329 
330             rc->TMN_TH -= (Int)((float)pMP->bitrate / (pMP->framerate + 0.0001) * (diff_BTCounter * 0.1));
331             rc->T = pMP->target_bits = rc->TMN_TH - rc->TMN_W;
332             pMP->diff_counter -= diff_BTCounter;
333 
334             rc->Rc = currVol->stream->byteCount << 3;   /* Total Bits for current frame */
335             rc->Hc = video->header_bits;    /* Total Bits in Header and Motion Vector */
336 
337             /* BX_RC */
338             updateRateControl(rc, video);
339 
340             break;
341 
342         default: /* for case CBR_1/2, VBR_1/2 */
343 
344             return PV_FAIL;
345     }
346 
347 
348     return PV_SUCCESS;
349 }
350 
351 /* ======================================================================== */
352 /*  Function : RC_GetSkipNextFrame, RC_GetRemainingVops                     */
353 /*  Date     : 2/20/2001                                                    */
354 /*  Purpose  : To access RC parameters from other parts of the code.        */
355 /*  In/out   :                                                              */
356 /*  Return   :                                                              */
357 /*  Modified :                                                              */
358 /* ======================================================================== */
359 
RC_GetSkipNextFrame(VideoEncData * video,Int currLayer)360 Int RC_GetSkipNextFrame(VideoEncData *video, Int currLayer)
361 {
362     return video->rc[currLayer]->skip_next_frame;
363 }
364 
RC_ResetSkipNextFrame(VideoEncData * video,Int currLayer)365 void RC_ResetSkipNextFrame(VideoEncData *video, Int currLayer)
366 {
367 
368     video->rc[currLayer]->skip_next_frame = 0;
369     return ;
370 }
371 
372 /* ======================================================================== */
373 /*  Function : RC_UpdateBuffer                                      */
374 /*  Date     : 2/20/2001                                                    */
375 /*  Purpose  : Update RC in case of there are frames skipped (camera freeze)*/
376 /*              from the application level in addition to what RC requested */
377 /*  In/out   : Nr, B, Rr                                                    */
378 /*  Return   : Void                                                         */
379 /*  Modified :                                                              */
380 /* ======================================================================== */
381 
382 
RC_UpdateBuffer(VideoEncData * video,Int currLayer,Int num_skip)383 PV_STATUS RC_UpdateBuffer(VideoEncData *video, Int currLayer, Int num_skip)
384 {
385     rateControl *rc  = video->rc[currLayer];
386     MultiPass   *pMP = video->pMP[currLayer];
387 
388     if (video == NULL || rc == NULL || pMP == NULL)
389         return PV_FAIL;
390 
391     rc->VBV_fullness   -= (Int)(rc->bitrate / rc->framerate * num_skip); //rc[currLayer]->Rp;
392     pMP->counter_BTsrc += 10 * num_skip;
393 
394     /* Check buffer underflow */
395     if (rc->VBV_fullness < rc->low_bound)
396     {
397         rc->VBV_fullness = rc->low_bound; // -rc->Bs/2;
398         rc->TMN_W = rc->VBV_fullness - rc->low_bound;
399         pMP->counter_BTsrc = pMP->counter_BTdst + (Int)((float)(rc->Bs / 2 - rc->low_bound) / 2.0 / (pMP->target_bits_per_frame / 10));
400     }
401 
402     return PV_SUCCESS;
403 }
404 
405 
406 /* ======================================================================== */
407 /*  Function : RC_UpdateBXRCParams                                          */
408 /*  Date     : 4/08/2002                                                    */
409 /*  Purpose  : Update RC parameters specifically for target bitrate or      */
410 /*             framerate update during an encoding session                  */
411 /*  In/out   :                                                              */
412 /*  Return   : PV_TRUE if successed, PV_FALSE if failed.                    */
413 /*  Modified :                                                              */
414 /* ======================================================================== */
415 
RC_UpdateBXRCParams(void * input)416 PV_STATUS RC_UpdateBXRCParams(void *input)
417 {
418     VideoEncData *video = (VideoEncData *) input;
419     VideoEncParams *encParams = video->encParams;
420     rateControl **rc = video->rc;
421     Int numLayers = encParams->nLayers;
422     Int *LayerBitRate = encParams->LayerBitRate;
423     float *LayerFrameRate = encParams->LayerFrameRate;
424     MultiPass **pMP = video->pMP;
425 
426     Int n, VBV_fullness;
427     Int diff_counter;
428 
429     extern Bool SetProfile_BufferSize(VideoEncData *video, float delay, Int bInitialized);
430 
431 
432     /* Reset video buffer size due to target bitrate change */
433     SetProfile_BufferSize(video, video->encParams->VBV_delay, 0); /* output: video->encParams->BufferSize[] */
434 
435     for (n = 0; n < numLayers; n++)
436     {
437         /* Remaining stuff about frame dropping and underflow check in update RC */
438         updateRC_PostProc(rc[n], video);
439         rc[n]->skip_next_frame = 0; /* must be initialized */
440 
441         /* New changes: bitrate and framerate, Bs, max_BitVariance_num, TMN_TH(optional), encoded_frames(optional) */
442         rc[n]->Bs = video->encParams->BufferSize[n];
443         VBV_fullness = (Int)(rc[n]->Bs * 0.5);
444 
445         if (n == 0)
446         {
447             rc[n]->TMN_TH = (Int)((float)LayerBitRate[n] / LayerFrameRate[n]);
448             rc[n]->bitrate   = pMP[n]->bitrate   = LayerBitRate[n];
449             rc[n]->framerate = pMP[n]->framerate = LayerFrameRate[n];
450 
451             // For h263 or short header mode, the bit variation is within (-2*Rmax*1001/3000, 2*Rmax*1001/3000)
452             if (video->encParams->H263_Enabled)
453             {
454                 rc[n]->max_BitVariance_num = (Int)((rc[n]->Bs - video->encParams->maxFrameSize) / 2 / (rc[n]->bitrate / rc[n]->framerate / 10.0)) - 5;
455                 //rc[n]->max_BitVariance_num = (Int)((float)(rc[n]->Bs - rc[n]->VBV_fullness)/((float)LayerBitRate[n]/LayerFrameRate[n]/10.0))-5;
456             }
457             else   // MPEG-4 normal modes
458             {
459                 rc[n]->max_BitVariance_num = (Int)((float)(rc[n]->Bs - VBV_fullness) * 10 / ((float)LayerBitRate[n] / LayerFrameRate[n])) - 5;
460             }
461         }
462         else
463         {
464             if (LayerFrameRate[n] - LayerFrameRate[n-1] > 0) /*  7/31/03 */
465             {
466                 rc[n]->TMN_TH = (Int)((float)(LayerBitRate[n] - LayerBitRate[n-1]) / (LayerFrameRate[n] - LayerFrameRate[n-1]));
467                 rc[n]->max_BitVariance_num = (Int)((float)(rc[n]->Bs - VBV_fullness) * 10 / ((float)rc[n]->TMN_TH)) - 5;
468                 if (rc[n]->max_BitVariance_num < 0) rc[n]->max_BitVariance_num += 5;
469             }
470             else   /*  7/31/03 */
471             {
472                 rc[n]->TMN_TH = 1 << 30;
473                 rc[n]->max_BitVariance_num = 0;
474             }
475             rc[n]->bitrate   = pMP[n]->bitrate   = LayerBitRate[n] - LayerBitRate[n-1];
476             rc[n]->framerate = pMP[n]->framerate = LayerFrameRate[n] - LayerFrameRate[n-1];
477         }
478 
479         pMP[n]->target_bits_per_frame_prev = pMP[n]->target_bits_per_frame;
480         pMP[n]->target_bits_per_frame = pMP[n]->bitrate / (float)(pMP[n]->framerate + 0.0001);  /*  7/31/03 */
481 
482         /* rc[n]->VBV_fullness and rc[n]->TMN_W should be kept same */
483         /* update pMP[n]->counter_BTdst and pMP[n]->counter_BTsrc   */
484         diff_counter = (Int)((float)(rc[n]->VBV_fullness - rc[n]->TMN_W) /
485                              (pMP[n]->target_bits_per_frame / 10 + 0.0001)); /*  7/31/03 */
486 
487         pMP[n]->counter_BTdst = pMP[n]->counter_BTsrc = 0;
488         if (diff_counter > 0)
489             pMP[n]->counter_BTdst = diff_counter;
490 
491         else if (diff_counter < 0)
492             pMP[n]->counter_BTsrc = -diff_counter;
493 
494         rc[n]->TMN_W = (Int)(rc[n]->VBV_fullness -      /* re-calculate rc[n]->TMN_W in order for higher accuracy */
495                              (pMP[n]->target_bits_per_frame / 10) * (pMP[n]->counter_BTdst - pMP[n]->counter_BTsrc));
496 
497         /* Keep the current average mad */
498         if (pMP[n]->aver_mad != 0)
499         {
500             pMP[n]->aver_mad_prev = pMP[n]->aver_mad;
501             pMP[n]->encoded_frames_prev = pMP[n]->encoded_frames;
502         }
503 
504         pMP[n]->aver_mad = 0;
505         pMP[n]->overlapped_win_size = 4;
506 
507         /* Misc */
508         pMP[n]->sum_mad = pMP[n]->sum_QP = 0;
509         //pMP[n]->encoded_frames_prev = pMP[n]->encoded_frames;
510         pMP[n]->encoded_frames = pMP[n]->re_encoded_frames = pMP[n]->re_encoded_times = 0;
511 
512     } /* end of: for(n=0; n<numLayers; n++) */
513 
514     return PV_SUCCESS;
515 
516 }
517 
518 
519 /* ================================================================================ */
520 /*  Function : targetBitCalculation                                                 */
521 /*  Date     : 10/01/2001                                                           */
522 /*  Purpose  : quadratic bit allocation model: T(n) = C*sqrt(mad(n)/aver_mad(n-1))  */
523 /*                                                                                  */
524 /*  In/out   : rc->T                                                                */
525 /*  Return   : Void                                                                 */
526 /*  Modified :                                                                      */
527 /* ================================================================================ */
528 
targetBitCalculation(void * input)529 void targetBitCalculation(void *input)
530 {
531     VideoEncData *video = (VideoEncData *) input;
532     MultiPass *pMP = video->pMP[video->currLayer];
533     Vol *currVol = video->vol[video->currLayer];
534     rateControl *rc = video->rc[video->currLayer];
535 
536     float curr_mad;//, average_mad;
537     Int diff_counter_BTsrc, diff_counter_BTdst, prev_counter_diff, curr_counter_diff, bound;
538     /* BT = Bit Transfer, for pMP->counter_BTsrc, pMP->counter_BTdst */
539 
540     if (video == NULL || currVol == NULL || pMP == NULL || rc == NULL)
541         return;
542 
543     /* some stuff about frame dropping remained here to be done because pMP cannot be inserted into updateRateControl()*/
544     updateRC_PostProc(rc, video);
545 
546     /* update pMP->counter_BTsrc and pMP->counter_BTdst to avoid interger overflow */
547     if (pMP->counter_BTsrc > 1000 && pMP->counter_BTdst > 1000)
548     {
549         pMP->counter_BTsrc -= 1000;
550         pMP->counter_BTdst -= 1000;
551     }
552 
553     /* ---------------------------------------------------------------------------------------------------*/
554     /* target calculation */
555     curr_mad = video->sumMAD / (float)currVol->nTotalMB;
556     if (curr_mad < MAD_MIN) curr_mad = MAD_MIN; /* MAD_MIN is defined as 1 in mp4def.h */
557     diff_counter_BTsrc = diff_counter_BTdst = 0;
558     pMP->diff_counter = 0;
559 
560 
561     /*1.calculate average mad */
562     pMP->sum_mad += curr_mad;
563     //average_mad = (pMP->encoded_frames < 1 ? curr_mad : pMP->sum_mad/(float)(pMP->encoded_frames+1)); /* this function is called from the scond encoded frame*/
564     //pMP->aver_mad = average_mad;
565     if (pMP->encoded_frames >= 0) /* pMP->encoded_frames is set to -1 initially, so forget about the very first I frame */
566         pMP->aver_mad = (pMP->aver_mad * pMP->encoded_frames + curr_mad) / (pMP->encoded_frames + 1);
567 
568     if (pMP->overlapped_win_size > 0 && pMP->encoded_frames_prev >= 0)  /*  7/31/03 */
569         pMP->aver_mad_prev = (pMP->aver_mad_prev * pMP->encoded_frames_prev + curr_mad) / (pMP->encoded_frames_prev + 1);
570 
571     /*2.average_mad, mad ==> diff_counter_BTsrc, diff_counter_BTdst */
572     if (pMP->overlapped_win_size == 0)
573     {
574         /* original verison */
575         if (curr_mad > pMP->aver_mad*1.1)
576         {
577             if (curr_mad / (pMP->aver_mad + 0.0001) > 2)
578                 diff_counter_BTdst = (Int)(M4VENC_SQRT(curr_mad / (pMP->aver_mad + 0.0001)) * 10 + 0.4) - 10;
579             //diff_counter_BTdst = (Int)((sqrt(curr_mad/pMP->aver_mad)*2+curr_mad/pMP->aver_mad)/(3*0.1) + 0.4) - 10;
580             else
581                 diff_counter_BTdst = (Int)(curr_mad / (pMP->aver_mad + 0.0001) * 10 + 0.4) - 10;
582         }
583         else /* curr_mad <= average_mad*1.1 */
584             //diff_counter_BTsrc = 10 - (Int)((sqrt(curr_mad/pMP->aver_mad) + pow(curr_mad/pMP->aver_mad, 1.0/3.0))/(2.0*0.1) + 0.4);
585             diff_counter_BTsrc = 10 - (Int)(M4VENC_SQRT(curr_mad / (pMP->aver_mad + 0.0001)) * 10 + 0.5);
586         //diff_counter_BTsrc = 10 - (Int)(curr_mad/pMP->aver_mad/0.1 + 0.5)
587 
588         /* actively fill in the possible gap */
589         if (diff_counter_BTsrc == 0 && diff_counter_BTdst == 0 &&
590                 curr_mad <= pMP->aver_mad*1.1 && pMP->counter_BTsrc < pMP->counter_BTdst)
591             diff_counter_BTsrc = 1;
592 
593     }
594     else if (pMP->overlapped_win_size > 0)
595     {
596         /* transition time: use previous average mad "pMP->aver_mad_prev" instead of the current average mad "pMP->aver_mad" */
597         if (curr_mad > pMP->aver_mad_prev*1.1)
598         {
599             if (curr_mad / pMP->aver_mad_prev > 2)
600                 diff_counter_BTdst = (Int)(M4VENC_SQRT(curr_mad / (pMP->aver_mad_prev + 0.0001)) * 10 + 0.4) - 10;
601             //diff_counter_BTdst = (Int)((M4VENC_SQRT(curr_mad/pMP->aver_mad_prev)*2+curr_mad/pMP->aver_mad_prev)/(3*0.1) + 0.4) - 10;
602             else
603                 diff_counter_BTdst = (Int)(curr_mad / (pMP->aver_mad_prev + 0.0001) * 10 + 0.4) - 10;
604         }
605         else /* curr_mad <= average_mad*1.1 */
606             //diff_counter_BTsrc = 10 - (Int)((sqrt(curr_mad/pMP->aver_mad_prev) + pow(curr_mad/pMP->aver_mad_prev, 1.0/3.0))/(2.0*0.1) + 0.4);
607             diff_counter_BTsrc = 10 - (Int)(M4VENC_SQRT(curr_mad / (pMP->aver_mad_prev + 0.0001)) * 10 + 0.5);
608         //diff_counter_BTsrc = 10 - (Int)(curr_mad/pMP->aver_mad_prev/0.1 + 0.5)
609 
610         /* actively fill in the possible gap */
611         if (diff_counter_BTsrc == 0 && diff_counter_BTdst == 0 &&
612                 curr_mad <= pMP->aver_mad_prev*1.1 && pMP->counter_BTsrc < pMP->counter_BTdst)
613             diff_counter_BTsrc = 1;
614 
615         if (--pMP->overlapped_win_size <= 0)    pMP->overlapped_win_size = 0;
616     }
617 
618 
619     /* if difference is too much, do clipping */
620     /* First, set the upper bound for current bit allocation variance: 80% of available buffer */
621     bound = (Int)((rc->Bs / 2 - rc->VBV_fullness) * 0.6 / (pMP->target_bits_per_frame / 10)); /* rc->Bs */
622     diff_counter_BTsrc =  PV_MIN(diff_counter_BTsrc, bound);
623     diff_counter_BTdst =  PV_MIN(diff_counter_BTdst, bound);
624 
625     /* Second, set another upper bound for current bit allocation: 4-5*bitrate/framerate */
626     bound = 50;
627 //  if(video->encParams->RC_Type == CBR_LOWDELAY)
628 //  not necessary       bound = 10;     /*  1/17/02 -- For Low delay */
629 
630     diff_counter_BTsrc =  PV_MIN(diff_counter_BTsrc, bound);
631     diff_counter_BTdst =  PV_MIN(diff_counter_BTdst, bound);
632 
633 
634     /* Third, check the buffer */
635     prev_counter_diff = pMP->counter_BTdst - pMP->counter_BTsrc;
636     curr_counter_diff = prev_counter_diff + (diff_counter_BTdst - diff_counter_BTsrc);
637 
638     if (PV_ABS(prev_counter_diff) >= rc->max_BitVariance_num || PV_ABS(curr_counter_diff) >= rc->max_BitVariance_num) // PV_ABS(curr_counter_diff) >= PV_ABS(prev_counter_diff) )
639     {   //diff_counter_BTsrc = diff_counter_BTdst = 0;
640 
641         if (curr_counter_diff > rc->max_BitVariance_num && diff_counter_BTdst)
642         {
643             diff_counter_BTdst = (rc->max_BitVariance_num - prev_counter_diff) + diff_counter_BTsrc;
644             if (diff_counter_BTdst < 0) diff_counter_BTdst = 0;
645         }
646 
647         else if (curr_counter_diff < -rc->max_BitVariance_num && diff_counter_BTsrc)
648         {
649             diff_counter_BTsrc = diff_counter_BTdst - (-rc->max_BitVariance_num - prev_counter_diff);
650             if (diff_counter_BTsrc < 0) diff_counter_BTsrc = 0;
651         }
652     }
653 
654 
655     /*3.diff_counter_BTsrc, diff_counter_BTdst ==> TMN_TH */
656     //rc->TMN_TH = (Int)((float)pMP->bitrate/pMP->framerate);
657     rc->TMN_TH = (Int)(pMP->target_bits_per_frame);
658     pMP->diff_counter = 0;
659 
660     if (diff_counter_BTsrc)
661     {
662         rc->TMN_TH -= (Int)(pMP->target_bits_per_frame * diff_counter_BTsrc * 0.1);
663         pMP->diff_counter = -diff_counter_BTsrc;
664     }
665     else if (diff_counter_BTdst)
666     {
667         rc->TMN_TH += (Int)(pMP->target_bits_per_frame * diff_counter_BTdst * 0.1);
668         pMP->diff_counter = diff_counter_BTdst;
669     }
670 
671 
672     /*4.update pMP->counter_BTsrc, pMP->counter_BTdst */
673     pMP->counter_BTsrc += diff_counter_BTsrc;
674     pMP->counter_BTdst += diff_counter_BTdst;
675 
676 
677     /*5.target bit calculation */
678     rc->T = rc->TMN_TH - rc->TMN_W;
679     //rc->T = rc->TMN_TH - (Int)((float)rc->TMN_W/rc->frameRate);
680 
681     if (video->encParams->H263_Enabled && rc->T > video->encParams->maxFrameSize)
682     {
683         rc->T = video->encParams->maxFrameSize;  //  added this 11/07/05
684     }
685 
686 }
687 
688 /* ================================================================================ */
689 /*  Function : calculateQuantizer_Multipass                                         */
690 /*  Date     : 10/01/2001                                                           */
691 /*  Purpose  : variable rate bit allocation + new QP determination scheme           */
692 /*                                                                                  */
693 /*  In/out   : rc->T and rc->Qc                                                     */
694 /*  Return   : Void                                                                 */
695 /*  Modified :                                                                      */
696 /* ================================================================================ */
697 
698 /* Mad based variable bit allocation + QP calculation with a new quadratic method */
calculateQuantizer_Multipass(void * input)699 void calculateQuantizer_Multipass(void *input)
700 {
701     VideoEncData *video = (VideoEncData *) input;
702     MultiPass *pMP = video->pMP[video->currLayer];
703     Vol *currVol = video->vol[video->currLayer];
704     rateControl *rc = video->rc[video->currLayer];
705 
706     Int prev_QP, prev_actual_bits, curr_target, i, j;
707 
708     float curr_mad, prev_mad, curr_RD, prev_RD, average_mad, aver_QP;
709 
710 
711     if (video == NULL || currVol == NULL || pMP == NULL || rc == NULL)
712         return;
713 
714     /* Mad based variable bit allocation */
715     targetBitCalculation((void*) video);
716 
717     if (rc->T <= 0 || video->sumMAD == 0)
718     {
719         if (rc->T < 0)  rc->Qc = 31;
720         return;
721     }
722 
723     /* ---------------------------------------------------------------------------------------------------*/
724     /* current frame QP estimation */
725     curr_target = rc->T;
726     curr_mad = video->sumMAD / (float)currVol->nTotalMB;
727     if (curr_mad < MAD_MIN) curr_mad = MAD_MIN; /* MAD_MIN is defined as 1 in mp4def.h */
728     curr_RD  = (float)curr_target / curr_mad;
729 
730     /* Another version of search the optimal point */
731     prev_actual_bits = pMP->pRDSamples[0][0].actual_bits;
732     prev_mad = pMP->pRDSamples[0][0].mad;
733 
734     for (i = 0, j = 0; i < pMP->frameRange; i++)
735     {
736         if (pMP->pRDSamples[i][0].mad != 0 && prev_mad != 0 &&
737                 PV_ABS(prev_mad - curr_mad) > PV_ABS(pMP->pRDSamples[i][0].mad - curr_mad))
738         {
739             prev_mad = pMP->pRDSamples[i][0].mad;
740             prev_actual_bits = pMP->pRDSamples[i][0].actual_bits;
741             j = i;
742         }
743     }
744     prev_QP = pMP->pRDSamples[j][0].QP;
745     for (i = 1; i < pMP->samplesPerFrame[j]; i++)
746     {
747         if (PV_ABS(prev_actual_bits - curr_target) > PV_ABS(pMP->pRDSamples[j][i].actual_bits - curr_target))
748         {
749             prev_actual_bits = pMP->pRDSamples[j][i].actual_bits;
750             prev_QP = pMP->pRDSamples[j][i].QP;
751         }
752     }
753 
754     // quadratic approximation
755     prev_RD = (float)prev_actual_bits / prev_mad;
756     //rc->Qc = (Int)(prev_QP * sqrt(prev_actual_bits/curr_target) + 0.4);
757     if (prev_QP == 1) // 11/14/05, added this to allow getting out of QP = 1 easily
758     {
759         rc->Qc = (Int)(prev_RD / curr_RD + 0.5);
760     }
761     else
762     {
763         rc->Qc = (Int)(prev_QP * M4VENC_SQRT(prev_RD / curr_RD) + 0.9);
764 
765         if (prev_RD / curr_RD > 0.5 && prev_RD / curr_RD < 2.0)
766             rc->Qc = (Int)(prev_QP * (M4VENC_SQRT(prev_RD / curr_RD) + prev_RD / curr_RD) / 2.0 + 0.9); /* Quadratic and linear approximation */
767         else
768             rc->Qc = (Int)(prev_QP * (M4VENC_SQRT(prev_RD / curr_RD) + M4VENC_POW(prev_RD / curr_RD, 1.0 / 3.0)) / 2.0 + 0.9);
769     }
770     //rc->Qc =(Int)(prev_QP * sqrt(prev_RD/curr_RD) + 0.4);
771     // 11/08/05
772     // lower bound on Qc should be a function of curr_mad
773     // When mad is already low, lower bound on Qc doesn't have to be small.
774     // Note, this doesn't work well for low complexity clip encoded at high bit rate
775     // it doesn't hit the target bit rate due to this QP lower bound.
776 /// if((curr_mad < 8) && (rc->Qc < 12)) rc->Qc = 12;
777 //  else    if((curr_mad < 128) && (rc->Qc < 3)) rc->Qc = 3;
778 
779     if (rc->Qc < 1) rc->Qc = 1;
780     if (rc->Qc > 31)    rc->Qc = 31;
781 
782 
783     /* active bit resource protection */
784     aver_QP = (pMP->encoded_frames == 0 ? 0 : pMP->sum_QP / (float)pMP->encoded_frames);
785     average_mad = (pMP->encoded_frames == 0 ? 0 : pMP->sum_mad / (float)pMP->encoded_frames); /* this function is called from the scond encoded frame*/
786     if (pMP->diff_counter == 0 &&
787             ((float)rc->Qc <= aver_QP*1.1 || curr_mad <= average_mad*1.1) &&
788             pMP->counter_BTsrc <= (pMP->counter_BTdst + (Int)(pMP->framerate*1.0 + 0.5)))
789     {
790         rc->TMN_TH -= (Int)(pMP->target_bits_per_frame / 10.0);
791         rc->T = rc->TMN_TH - rc->TMN_W;
792         pMP->counter_BTsrc++;
793         pMP->diff_counter--;
794     }
795 
796 }
797 
798 
799 /* ======================================================================== */
800 /*  Function : updateRateControl                                            */
801 /*  Date     : 11/17/2000                                                   */
802 /*  Purpose  :Update the RD Modal (After Encoding the Current Frame)        */
803 /*  In/out   :                                                              */
804 /*  Return   :                                                              */
805 /*  Modified :                                                              */
806 /* ======================================================================== */
807 
updateRateControl(rateControl * rc,VideoEncData * video)808 void updateRateControl(rateControl *rc, VideoEncData *video)
809 {
810     Int  frame_bits;
811 
812 
813     /* rate contro\l */
814     frame_bits = (Int)(rc->bitrate / rc->framerate);
815     rc->TMN_W += (rc->Rc - rc->TMN_TH);
816     rc->VBV_fullness += (rc->Rc - frame_bits); //rc->Rp);
817     //if(rc->VBV_fullness < 0) rc->VBV_fullness = -1;
818 
819     rc->encoded_frames++;
820 
821     /* frame dropping */
822     rc->skip_next_frame = 0;
823 
824     if ((video->encParams->H263_Enabled && rc->Rc > video->encParams->maxFrameSize) || /*  For H263/short header mode, drop the frame if the actual frame size exceeds the bound */
825             (rc->VBV_fullness > rc->Bs / 2 && !rc->no_pre_skip)) /* skip the current frame */ /* rc->Bs */
826     {
827         rc->TMN_W -= (rc->Rc - rc->TMN_TH);
828         rc->VBV_fullness -= rc->Rc;
829         rc->skip_next_frame = -1;
830     }
831     else if ((float)(rc->VBV_fullness - rc->VBV_fullness_offset) > (rc->Bs / 2 - rc->VBV_fullness_offset)*0.95 &&
832              !rc->no_frame_skip) /* skip next frame */
833     {
834         rc->VBV_fullness -= frame_bits; //rc->Rp;
835         rc->skip_next_frame = 1;
836         /*  skip more than 1 frames  */
837         //while(rc->VBV_fullness > rc->Bs*0.475)
838         while ((rc->VBV_fullness - rc->VBV_fullness_offset) > (rc->Bs / 2 - rc->VBV_fullness_offset)*0.95)
839         {
840             rc->VBV_fullness -= frame_bits; //rc->Rp;
841             rc->skip_next_frame++;
842         }
843         /* END  */
844     }
845 
846 }
847 
848 /* ======================================================================== */
849 /*  Function : updateRC_PostProc                                            */
850 /*  Date     : 04/08/2002                                                   */
851 /*  Purpose  : Remaing RC update stuff for frame skip and buffer underflow  */
852 /*             check                                                        */
853 /*  In/out   :                                                              */
854 /*  Return   :                                                              */
855 /*  Modified :                                                              */
856 /* ======================================================================== */
updateRC_PostProc(rateControl * rc,VideoEncData * video)857 void updateRC_PostProc(rateControl *rc, VideoEncData *video)
858 {
859     MultiPass *pMP = video->pMP[video->currLayer];
860 
861     if (rc->skip_next_frame == 1 && !rc->no_frame_skip) /* skip next frame */
862     {
863         pMP->counter_BTsrc += 10 * rc->skip_next_frame;
864 
865     }
866     else if (rc->skip_next_frame == -1 && !rc->no_pre_skip) /* skip current frame */
867     {
868         pMP->counter_BTdst -= pMP->diff_counter;
869         pMP->counter_BTsrc += 10;
870 
871         pMP->sum_mad -= pMP->mad;
872         pMP->aver_mad = (pMP->aver_mad * pMP->encoded_frames - pMP->mad) / (float)(pMP->encoded_frames - 1 + 0.0001);
873         pMP->sum_QP  -= pMP->QP;
874         pMP->encoded_frames --;
875     }
876     /* some stuff in update VBV_fullness remains here */
877     //if(rc->VBV_fullness < -rc->Bs/2) /* rc->Bs */
878     if (rc->VBV_fullness < rc->low_bound)
879     {
880         rc->VBV_fullness = rc->low_bound; // -rc->Bs/2;
881         rc->TMN_W = rc->VBV_fullness - rc->low_bound;
882         pMP->counter_BTsrc = pMP->counter_BTdst + (Int)((float)(rc->Bs / 2 - rc->low_bound) / 2.0 / (pMP->target_bits_per_frame / 10));
883     }
884 }
885 
886