1 /******************************************************************************
2  *
3  * Copyright (C) 2015 The Android Open Source Project
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  * Originally developed and contributed by Ittiam Systems Pvt. Ltd, Bangalore
19 */
20 
21 /** Includes */
22 #include <stdio.h>
23 #include <string.h>
24 #include "irc_datatypes.h"
25 #include "irc_mem_req_and_acq.h"
26 #include "irc_common.h"
27 #include "irc_cntrl_param.h"
28 #include "irc_fixed_point_error_bits.h"
29 #include "irc_rd_model.h"
30 #include "irc_est_sad.h"
31 #include "irc_picture_type.h"
32 #include "irc_bit_allocation.h"
33 #include "irc_trace_support.h"
34 
35 /** Macros **/
36 #define MIN(x,y)  ((x) < (y))? (x) : (y)
37 
38 /* State structure for bit allocation */
39 typedef struct
40 {
41     /* using var_q number as it can cross 31 bits for large intra frameinterval */
42     number_t vq_rem_bits_in_period;
43 
44     /* Storing inputs */
45     WORD32 i4_tot_frms_in_gop;
46 
47     WORD32 i4_num_intra_frm_interval;
48 
49     WORD32 i4_bits_per_frm;
50 
51 } rem_bit_in_prd_t;
52 
53 typedef struct bit_allocation_t
54 {
55     rem_bit_in_prd_t s_rbip;
56 
57     /* A universal constant giving the relative complexity between pictures */
58     WORD32 i2_K[MAX_PIC_TYPE];
59 
60     /* To get a estimate of the header bits consumed */
61     WORD32 i4_prev_frm_header_bits[MAX_PIC_TYPE];
62 
63     WORD32 i4_bits_per_frm;
64 
65     WORD32 i4_num_gops_in_period;
66 
67     /* Num gops as set by rate control module */
68     WORD32 i4_actual_num_gops_in_period;
69 
70     number_t vq_saved_bits;
71 
72     WORD32 i4_max_bits_per_frm[MAX_NUM_DRAIN_RATES];
73 
74     WORD32 i4_min_bits_per_frm;
75 
76     /* Error bits module */
77     error_bits_handle ps_error_bits;
78 
79     /* Storing frame rate */
80     WORD32 i4_frame_rate;
81 
82     WORD32 i4_bit_rate;
83 
84     WORD32 ai4_peak_bit_rate[MAX_NUM_DRAIN_RATES];
85 
86 } bit_allocation_t;
87 
get_number_of_frms_in_a_gop(pic_handling_handle ps_pic_handling)88 static WORD32 get_number_of_frms_in_a_gop(pic_handling_handle ps_pic_handling)
89 {
90     WORD32 i4_tot_frms_in_gop = 0, i;
91     WORD32 ai4_frms_in_gop[MAX_PIC_TYPE];
92 
93     /* Query the pic_handling struct for the rem frames in the period */
94     irc_pic_type_get_frms_in_gop(ps_pic_handling, ai4_frms_in_gop);
95 
96     /* Get the total frms in the gop */
97     i4_tot_frms_in_gop = 0;
98     for(i = 0; i < MAX_PIC_TYPE; i++)
99     {
100         i4_tot_frms_in_gop += ai4_frms_in_gop[i];
101     }
102     return (i4_tot_frms_in_gop);
103 }
104 
init_rbip(rem_bit_in_prd_t * ps_rbip,pic_handling_handle ps_pic_handling,WORD32 i4_bits_per_frm,WORD32 i4_num_intra_frm_interval)105 static void init_rbip(rem_bit_in_prd_t *ps_rbip,
106                       pic_handling_handle ps_pic_handling,
107                       WORD32 i4_bits_per_frm,
108                       WORD32 i4_num_intra_frm_interval)
109 {
110     WORD32 i4_tot_frms_in_gop = get_number_of_frms_in_a_gop(ps_pic_handling);
111 
112     /* rem_bits_in_period = bits_per_frm * tot_frms_in_gop * num_intra_frm_interval */
113     {
114         number_t vq_bits_per_frm, vq_tot_frms_in_gop, vq_num_intra_frm_interval;
115         number_t *pvq_rem_bits_in_period = &ps_rbip->vq_rem_bits_in_period;
116 
117         SET_VAR_Q(vq_bits_per_frm, i4_bits_per_frm, 0);
118         SET_VAR_Q(vq_tot_frms_in_gop, i4_tot_frms_in_gop, 0);
119         SET_VAR_Q(vq_num_intra_frm_interval, i4_num_intra_frm_interval, 0);
120 
121         /* rem_bits_in_period = bits_per_frm * tot_frms_in_gop */
122         mult32_var_q(vq_bits_per_frm, vq_tot_frms_in_gop,
123                      pvq_rem_bits_in_period);
124 
125         /* rem_bits_in_period *= num_intra_frm_interval */
126         mult32_var_q(vq_num_intra_frm_interval, pvq_rem_bits_in_period[0],
127                      pvq_rem_bits_in_period);
128     }
129 
130     /*
131      * Store the total number of frames in GOP value which is
132      * used from module A
133      */
134     ps_rbip->i4_tot_frms_in_gop = i4_tot_frms_in_gop;
135     ps_rbip->i4_num_intra_frm_interval = i4_num_intra_frm_interval;
136     ps_rbip->i4_bits_per_frm = i4_bits_per_frm;
137 }
138 
check_update_rbip(rem_bit_in_prd_t * ps_rbip,pic_handling_handle ps_pic_handling)139 static void check_update_rbip(rem_bit_in_prd_t *ps_rbip,
140                               pic_handling_handle ps_pic_handling)
141 {
142     /*
143      * NOTE: Intra frame interval changes after the first I frame that is
144      * encoded in a GOP
145      */
146     WORD32 i4_new_tot_frms_in_gop = get_number_of_frms_in_a_gop(
147                     ps_pic_handling);
148 
149     if(i4_new_tot_frms_in_gop != ps_rbip->i4_tot_frms_in_gop)
150     {
151         WORD32 i4_rem_frames_in_period =
152                         ps_rbip->i4_num_intra_frm_interval
153                                         * (i4_new_tot_frms_in_gop
154                                                         - ps_rbip->i4_tot_frms_in_gop);
155 
156         number_t vq_rem_frms_in_period, s_bits_per_frm, vq_delta_bits_in_period;
157 
158         SET_VAR_Q(vq_rem_frms_in_period, i4_rem_frames_in_period, 0);
159         SET_VAR_Q(s_bits_per_frm, ps_rbip->i4_bits_per_frm, 0);
160 
161         /* delta_bits_in_period = bits_per_frm * rem_frms_in_period */
162         mult32_var_q(s_bits_per_frm, vq_rem_frms_in_period,
163                      &vq_delta_bits_in_period);
164 
165         /* rem_bits_in_period += delta_bits_in_period */
166         add32_var_q(vq_delta_bits_in_period, ps_rbip->vq_rem_bits_in_period,
167                     &ps_rbip->vq_rem_bits_in_period);
168     }
169     /* Updated the new values */
170     ps_rbip->i4_tot_frms_in_gop = i4_new_tot_frms_in_gop;
171 }
172 
irc_ba_update_rbip(rem_bit_in_prd_t * ps_rbip,pic_handling_handle ps_pic_handling,WORD32 i4_num_of_bits)173 static void irc_ba_update_rbip(rem_bit_in_prd_t *ps_rbip,
174                                pic_handling_handle ps_pic_handling,
175                                WORD32 i4_num_of_bits)
176 {
177     number_t vq_num_bits;
178 
179     check_update_rbip(ps_rbip, ps_pic_handling);
180 
181     /* rem_bits_in_period += num_of_bits */
182     SET_VAR_Q(vq_num_bits, i4_num_of_bits, 0);
183     add32_var_q(vq_num_bits, ps_rbip->vq_rem_bits_in_period,
184                 &ps_rbip->vq_rem_bits_in_period);
185 }
186 
irc_ba_change_rbip(rem_bit_in_prd_t * ps_rbip,pic_handling_handle ps_pic_handling,WORD32 i4_new_bits_per_frm,WORD32 i4_new_num_intra_frm_interval)187 static void irc_ba_change_rbip(rem_bit_in_prd_t *ps_rbip,
188                                pic_handling_handle ps_pic_handling,
189                                WORD32 i4_new_bits_per_frm,
190                                WORD32 i4_new_num_intra_frm_interval)
191 {
192     WORD32 ai4_rem_frms_in_period[MAX_PIC_TYPE], i4_rem_frms_in_gop, i;
193     irc_pic_type_get_rem_frms_in_gop(ps_pic_handling, ai4_rem_frms_in_period);
194 
195     i4_rem_frms_in_gop = 0;
196     for(i = 0; i < MAX_PIC_TYPE; i++)
197         i4_rem_frms_in_gop += ai4_rem_frms_in_period[i];
198 
199     if(i4_new_bits_per_frm != ps_rbip->i4_bits_per_frm)
200     {
201         WORD32 i4_rem_frms_in_period = (ps_rbip->i4_num_intra_frm_interval - 1)
202                         * ps_rbip->i4_tot_frms_in_gop + i4_rem_frms_in_gop;
203 
204         number_t vq_rem_frms_in_period, vq_delta_bits_per_frm,
205                         vq_delta_bits_in_period;
206 
207         /* delta_bits_per_frm = new_bits_per_frm - old_bits_per_frm */
208         SET_VAR_Q(vq_delta_bits_per_frm,
209                   (i4_new_bits_per_frm - ps_rbip->i4_bits_per_frm), 0);
210 
211         SET_VAR_Q(vq_rem_frms_in_period, i4_rem_frms_in_period, 0);
212 
213         /* delta_bits_in_period = delta_bits_per_frm * rem_frms_in_period */
214         mult32_var_q(vq_delta_bits_per_frm, vq_rem_frms_in_period,
215                      &vq_delta_bits_in_period);
216 
217         /* ps_rbip->rem_bits_in_period += delta_bits_in_period */
218         add32_var_q(vq_delta_bits_in_period, ps_rbip->vq_rem_bits_in_period,
219                     &ps_rbip->vq_rem_bits_in_period);
220     }
221 
222     if(i4_new_num_intra_frm_interval != ps_rbip->i4_num_intra_frm_interval)
223     {
224         WORD32 i4_rem_frms_in_period = ps_rbip->i4_tot_frms_in_gop
225                         * (i4_new_num_intra_frm_interval
226                                         - ps_rbip->i4_num_intra_frm_interval);
227 
228         number_t vq_rem_frms_in_period, vq_new_bits_per_frm,
229                         vq_delta_bits_in_period;
230 
231         /* new_bits_per_frm = new_new_bits_per_frm - old_new_bits_per_frm */
232         SET_VAR_Q(vq_new_bits_per_frm, i4_new_bits_per_frm, 0);
233 
234         SET_VAR_Q(vq_rem_frms_in_period, i4_rem_frms_in_period, 0);
235 
236         /* delta_bits_in_period = new_bits_per_frm * rem_frms_in_period */
237         mult32_var_q(vq_new_bits_per_frm, vq_rem_frms_in_period,
238                      &vq_delta_bits_in_period);
239 
240         /* ps_rbip->rem_bits_in_period += delta_bits_in_period */
241         add32_var_q(vq_delta_bits_in_period, ps_rbip->vq_rem_bits_in_period,
242                     &ps_rbip->vq_rem_bits_in_period);
243     }
244     /* Update the new value */
245     ps_rbip->i4_num_intra_frm_interval = i4_new_num_intra_frm_interval;
246     ps_rbip->i4_bits_per_frm = i4_new_bits_per_frm;
247 }
248 
irc_ba_num_fill_use_free_memtab(bit_allocation_t ** pps_bit_allocation,itt_memtab_t * ps_memtab,ITT_FUNC_TYPE_E e_func_type)249 WORD32 irc_ba_num_fill_use_free_memtab(bit_allocation_t **pps_bit_allocation,
250                                        itt_memtab_t *ps_memtab,
251                                        ITT_FUNC_TYPE_E e_func_type)
252 {
253     WORD32 i4_mem_tab_idx = 0;
254     bit_allocation_t s_bit_allocation_temp;
255 
256     /*
257      * Hack for all alloc, during which we don't have any state memory.
258      * Dereferencing can cause issues
259      */
260     if(e_func_type == GET_NUM_MEMTAB || e_func_type == FILL_MEMTAB)
261         (*pps_bit_allocation) = &s_bit_allocation_temp;
262 
263     /*for src rate control state structure*/
264     if(e_func_type != GET_NUM_MEMTAB)
265     {
266         fill_memtab(&ps_memtab[i4_mem_tab_idx], sizeof(bit_allocation_t),
267                     ALIGN_128_BYTE, PERSISTENT, DDR);
268         use_or_fill_base(&ps_memtab[0], (void**)pps_bit_allocation,
269                          e_func_type);
270     }
271     i4_mem_tab_idx++;
272 
273     i4_mem_tab_idx += irc_error_bits_num_fill_use_free_memtab(
274                     &pps_bit_allocation[0]->ps_error_bits,
275                     &ps_memtab[i4_mem_tab_idx], e_func_type);
276 
277     return (i4_mem_tab_idx);
278 }
279 
280 /*******************************************************************************
281  Function Name : irc_ba_init_bit_allocation
282  Description   : Initialize the bit_allocation structure.
283  ******************************************************************************/
irc_ba_init_bit_allocation(bit_allocation_t * ps_bit_allocation,pic_handling_handle ps_pic_handling,WORD32 i4_num_intra_frm_interval,WORD32 i4_bit_rate,WORD32 i4_frm_rate,WORD32 * i4_peak_bit_rate,WORD32 i4_min_bitrate)284 void irc_ba_init_bit_allocation(bit_allocation_t *ps_bit_allocation,
285                                 pic_handling_handle ps_pic_handling,
286                                 WORD32 i4_num_intra_frm_interval,
287                                 WORD32 i4_bit_rate,
288                                 WORD32 i4_frm_rate,
289                                 WORD32 *i4_peak_bit_rate,
290                                 WORD32 i4_min_bitrate)
291 {
292     WORD32 i;
293     WORD32 i4_bits_per_frm, i4_max_bits_per_frm[MAX_NUM_DRAIN_RATES];
294 
295     /* Calculate the bits per frame */
296     X_PROD_Y_DIV_Z(i4_bit_rate, 1000, i4_frm_rate, i4_bits_per_frm);
297     for(i = 0; i < MAX_NUM_DRAIN_RATES; i++)
298     {
299         X_PROD_Y_DIV_Z(i4_peak_bit_rate[i], 1000, i4_frm_rate,
300                        i4_max_bits_per_frm[i]);
301     }
302     /* Initialize the bits_per_frame */
303     ps_bit_allocation->i4_bits_per_frm = i4_bits_per_frm;
304     for(i = 0; i < MAX_NUM_DRAIN_RATES; i++)
305     {
306         ps_bit_allocation->i4_max_bits_per_frm[i] = i4_max_bits_per_frm[i];
307     }
308     X_PROD_Y_DIV_Z(i4_min_bitrate, 1000, i4_frm_rate,
309                    ps_bit_allocation->i4_min_bits_per_frm);
310 
311     /*
312      * Initialize the rem_bits in period
313      * The first gop in case of an OPEN GOP may have fewer B_PICs,
314      * That condition is not taken care of
315      */
316     init_rbip(&ps_bit_allocation->s_rbip, ps_pic_handling, i4_bits_per_frm,
317               i4_num_intra_frm_interval);
318 
319     /* Initialize the num_gops_in_period */
320     ps_bit_allocation->i4_num_gops_in_period = i4_num_intra_frm_interval;
321     ps_bit_allocation->i4_actual_num_gops_in_period = i4_num_intra_frm_interval;
322 
323     /* Relative complexity between I and P frames */
324     ps_bit_allocation->i2_K[I_PIC] = (1 << K_Q);
325     ps_bit_allocation->i2_K[P_PIC] = I_TO_P_RATIO;
326     ps_bit_allocation->i2_K[B_PIC] = (P_TO_B_RATIO * I_TO_P_RATIO) >> K_Q;
327 
328     /* Initialize the saved bits to 0*/
329     SET_VAR_Q(ps_bit_allocation->vq_saved_bits, 0, 0);
330 
331     /* Update the error bits module with average bits */
332     irc_init_error_bits(ps_bit_allocation->ps_error_bits, i4_frm_rate,
333                         i4_bit_rate);
334     /* Store the input for implementing change in values */
335     ps_bit_allocation->i4_frame_rate = i4_frm_rate;
336     ps_bit_allocation->i4_bit_rate = i4_bit_rate;
337 
338     memset(ps_bit_allocation->i4_prev_frm_header_bits, 0, sizeof(ps_bit_allocation->i4_prev_frm_header_bits));
339     for(i=0;i<MAX_NUM_DRAIN_RATES;i++)
340         ps_bit_allocation->ai4_peak_bit_rate[i] = i4_peak_bit_rate[i];
341 }
342 
343 /*******************************************************************************
344  Function Name : get_cur_frm_est_bits
345  Description   : Based on remaining bits in period and rd_model
346  the number of bits required for the current frame is estimated.
347  ******************************************************************************/
irc_ba_get_cur_frm_est_texture_bits(bit_allocation_t * ps_bit_allocation,rc_rd_model_handle * pps_rd_model,est_sad_handle ps_est_sad,pic_handling_handle ps_pic_handling,picture_type_e e_pic_type)348 WORD32 irc_ba_get_cur_frm_est_texture_bits(bit_allocation_t *ps_bit_allocation,
349                                            rc_rd_model_handle *pps_rd_model,
350                                            est_sad_handle ps_est_sad,
351                                            pic_handling_handle ps_pic_handling,
352                                            picture_type_e e_pic_type)
353 {
354     WORD32 i, j;
355     WORD32 i4_est_texture_bits_for_frm;
356     number_t vq_rem_texture_bits;
357     number_t vq_complexity_estimate[MAX_PIC_TYPE];
358     WORD32 i4_rem_frms_in_period[MAX_PIC_TYPE], i4_frms_in_period[MAX_PIC_TYPE];
359     number_t vq_max_consumable_bits;
360     number_t vq_rem_frms_in_period[MAX_PIC_TYPE], vq_est_texture_bits_for_frm;
361     number_t vq_prev_hdr_bits[MAX_PIC_TYPE];
362 
363     WORD32 complexity_est = 0;
364 
365     /* Get the rem_frms_in_gop & the frms_in_gop from the pic_type state struct */
366     irc_pic_type_get_rem_frms_in_gop(ps_pic_handling, i4_rem_frms_in_period);
367     irc_pic_type_get_frms_in_gop(ps_pic_handling, i4_frms_in_period);
368 
369     /* Depending on the number of gops in a period, find the num_frms_in_prd */
370     for(j = 0; j < MAX_PIC_TYPE; j++)
371     {
372         i4_rem_frms_in_period[j] += (i4_frms_in_period[j]
373                         * (ps_bit_allocation->i4_num_gops_in_period - 1));
374         i4_frms_in_period[j] *= ps_bit_allocation->i4_num_gops_in_period;
375     }
376 
377     /* Remove the header bits from the remaining bits to find how many bits you
378      can transfer.*/
379     irc_ba_update_rbip(&ps_bit_allocation->s_rbip, ps_pic_handling, 0);
380     for(i = 0; i < MAX_PIC_TYPE; i++)
381     {
382         SET_VAR_Q(vq_rem_frms_in_period[i], i4_rem_frms_in_period[i], 0);
383         SET_VAR_Q(vq_prev_hdr_bits[i],
384                   ps_bit_allocation->i4_prev_frm_header_bits[i], 0);
385     }
386     {
387         /*
388          *rem_texture_bits = rem_bits_in_period -
389          *(rem_frms_in_period[I_PIC] * prev_frm_header_bits[I_PIC]) -
390          *(rem_frms_in_period[P_PIC] * prev_frm_header_bits[P_PIC]) -
391          *(rem_frms_in_period[B_PIC] * prev_frm_header_bits[B_PIC]);
392          */
393         number_t vq_rem_hdr_bits;
394         vq_rem_texture_bits = ps_bit_allocation->s_rbip.vq_rem_bits_in_period;
395 
396         mult32_var_q(vq_prev_hdr_bits[I_PIC], vq_rem_frms_in_period[I_PIC],
397                      &vq_rem_hdr_bits);
398         sub32_var_q(vq_rem_texture_bits, vq_rem_hdr_bits, &vq_rem_texture_bits);
399 
400         mult32_var_q(vq_prev_hdr_bits[P_PIC], vq_rem_frms_in_period[P_PIC],
401                      &vq_rem_hdr_bits);
402         sub32_var_q(vq_rem_texture_bits, vq_rem_hdr_bits, &vq_rem_texture_bits);
403 
404         mult32_var_q(vq_prev_hdr_bits[B_PIC], vq_rem_frms_in_period[B_PIC],
405                      &vq_rem_hdr_bits);
406         sub32_var_q(vq_rem_texture_bits, vq_rem_hdr_bits, &vq_rem_texture_bits);
407     }
408     {
409         /* max_consumable_bits =
410          *(frms_in_period[I_PIC] * max_bits_per_frm[0] ) +
411          *(frms_in_period[P_PIC] + frms_in_period[B_PIC] ) * max_bits_per_frm[1];
412          */
413         number_t vq_max_bits, vq_max_bits_per_frm[2];
414 
415         SET_VAR_Q(vq_max_bits_per_frm[0],
416                   ps_bit_allocation->i4_max_bits_per_frm[0], 0);
417         SET_VAR_Q(vq_max_bits_per_frm[1],
418                   ps_bit_allocation->i4_max_bits_per_frm[1], 0);
419 
420         mult32_var_q(vq_rem_frms_in_period[I_PIC], vq_max_bits_per_frm[0],
421                      &vq_max_bits);
422         vq_max_consumable_bits = vq_max_bits;
423 
424         mult32_var_q(vq_rem_frms_in_period[P_PIC], vq_max_bits_per_frm[1],
425                      &vq_max_bits);
426         add32_var_q(vq_max_bits, vq_max_consumable_bits,
427                     &vq_max_consumable_bits);
428 
429         mult32_var_q(vq_rem_frms_in_period[B_PIC], vq_max_bits_per_frm[1],
430                      &vq_max_bits);
431         add32_var_q(vq_max_bits, vq_max_consumable_bits,
432                     &vq_max_consumable_bits);
433     }
434 
435     /* rem_texture_bits = MIN(rem_texture_bits, max_consumable_bits) */
436     MIN_VARQ(vq_max_consumable_bits, vq_rem_texture_bits, vq_rem_texture_bits);
437 
438     /* The bits are then allocated based on the relative complexity of the
439      current frame with respect to that of the rest of the frames in period */
440     for(i = 0; i < MAX_PIC_TYPE; i++)
441     {
442         number_t vq_lin_mod_coeff, vq_est_sad, vq_K;
443 
444         /* Getting the linear model coefficient */
445         vq_lin_mod_coeff = irc_get_linear_coefficient(pps_rd_model[i]);
446 
447         /* Getting the estimated SAD */
448         SET_VAR_Q(vq_est_sad, irc_get_est_sad(ps_est_sad,i), 0);
449 
450         /* Making K factor a var Q format */
451         SET_VAR_Q(vq_K, ps_bit_allocation->i2_K[i], K_Q);
452 
453         /* Complexity_estimate = [ (lin_mod_coeff * estimated_sad) / K factor ]  */
454         mult32_var_q(vq_lin_mod_coeff, vq_est_sad, &vq_lin_mod_coeff);
455         div32_var_q(vq_lin_mod_coeff, vq_K, &vq_complexity_estimate[i]);
456     }
457 
458     /*
459      * For simple cases, one of the complexities go to zero and in those cases
460      * distribute the bits evenly among frames based on I_TO_P_RATIO
461      */
462 
463     /* Also check the B-pictures complexity only in case they are present*/
464     if(i4_frms_in_period[B_PIC] == 0)
465     {
466         complexity_est = (vq_complexity_estimate[I_PIC]
467                         && vq_complexity_estimate[P_PIC]);
468     }
469     else
470     {
471         complexity_est = (vq_complexity_estimate[I_PIC]
472                         && vq_complexity_estimate[P_PIC]
473                         && vq_complexity_estimate[B_PIC]);
474     }
475 
476     if(complexity_est)
477     {
478         /*
479          * Estimated texture bits =
480          * (remaining bits) * (cur frm complexity)
481          * ---------------------------------------
482          * (num_i_frm*i_frm_complexity) + (num_p_frm*pfrm_complexity)
483          *  + (b_frm * b_frm_cm)
484          */
485         mult32_var_q(vq_rem_texture_bits, vq_complexity_estimate[e_pic_type],
486                      &vq_rem_texture_bits);
487 
488         for(i = 0; i < MAX_PIC_TYPE; i++)
489         {
490             mult32_var_q(vq_rem_frms_in_period[i], vq_complexity_estimate[i],
491                          &vq_rem_frms_in_period[i]);
492         }
493 
494         add32_var_q(vq_rem_frms_in_period[I_PIC], vq_rem_frms_in_period[P_PIC],
495                     &vq_rem_frms_in_period[I_PIC]);
496 
497         add32_var_q(vq_rem_frms_in_period[I_PIC], vq_rem_frms_in_period[B_PIC],
498                     &vq_rem_frms_in_period[I_PIC]);
499 
500         div32_var_q(vq_rem_texture_bits, vq_rem_frms_in_period[I_PIC],
501                     &vq_est_texture_bits_for_frm);
502 
503         number_t_to_word32(vq_est_texture_bits_for_frm,
504                            &i4_est_texture_bits_for_frm);
505     }
506     else
507     {
508         number_t vq_i_to_p_bit_ratio, vq_rem_frms;
509 
510         SET_VAR_Q(vq_i_to_p_bit_ratio, I_TO_P_BIT_RATIO, 0);
511 
512         /* rem_frms = ((I_TO_P_BIT_RATIO * rem_frms_in_period[I_PIC]) +
513          * rem_frms_in_period[P_PIC]  +  rem_frms_in_period[B_PIC]);
514          */
515         mult32_var_q(vq_rem_frms_in_period[I_PIC], vq_i_to_p_bit_ratio,
516                      &vq_rem_frms);
517         add32_var_q(vq_rem_frms_in_period[P_PIC], vq_rem_frms, &vq_rem_frms);
518         add32_var_q(vq_rem_frms_in_period[B_PIC], vq_rem_frms, &vq_rem_frms);
519 
520         /* est_texture_bits_for_frm = rem_texture_bits / rem_frms */
521         div32_var_q(vq_rem_texture_bits, vq_rem_frms,
522                     &vq_est_texture_bits_for_frm);
523         number_t_to_word32(vq_est_texture_bits_for_frm,
524                            &i4_est_texture_bits_for_frm);
525 
526         i4_est_texture_bits_for_frm =
527                         (I_PIC == e_pic_type) ?
528                                         (i4_est_texture_bits_for_frm
529                                                         * I_TO_P_BIT_RATIO) :
530                                         i4_est_texture_bits_for_frm;
531     }
532 
533     /*
534      * If the remaining bits in the period becomes negative then the estimated
535      * texture bits would also become negative. This would send a feedback to
536      * the model which may go for a toss. Thus sending the minimum possible
537      * value = 0
538      */
539     if(i4_est_texture_bits_for_frm < 0)
540     {
541         i4_est_texture_bits_for_frm = 0;
542     }
543 
544     return (i4_est_texture_bits_for_frm);
545 }
546 
547 /******************************************************************************
548  Function Name : irc_ba_get_cur_frm_est_header_bits
549  Description   : Based on remaining bits in period and rd_model
550                  the number of bits required for the current frame is estimated.
551  ******************************************************************************/
irc_ba_get_cur_frm_est_header_bits(bit_allocation_t * ps_bit_allocation,picture_type_e e_pic_type)552 WORD32 irc_ba_get_cur_frm_est_header_bits(bit_allocation_t *ps_bit_allocation,
553                                           picture_type_e e_pic_type)
554 {
555     return (ps_bit_allocation->i4_prev_frm_header_bits[e_pic_type]);
556 }
557 
irc_ba_get_rem_bits_in_period(bit_allocation_t * ps_bit_allocation,pic_handling_handle ps_pic_handling)558 WORD32 irc_ba_get_rem_bits_in_period(bit_allocation_t *ps_bit_allocation,
559                                      pic_handling_handle ps_pic_handling)
560 {
561     WORD32 i4_rem_bits_in_gop = 0;
562     irc_ba_update_rbip(&ps_bit_allocation->s_rbip, ps_pic_handling, 0);
563     number_t_to_word32(ps_bit_allocation->s_rbip.vq_rem_bits_in_period,
564                        &i4_rem_bits_in_gop);
565     return (i4_rem_bits_in_gop);
566 }
567 
568 /*******************************************************************************
569  Function Name : irc_ba_update_cur_frm_consumed_bits
570  Description   : Based on remaining bits in period and rd_model
571                  the number of bits required for the current frame is estimated.
572  ******************************************************************************/
irc_ba_update_cur_frm_consumed_bits(bit_allocation_t * ps_bit_allocation,pic_handling_handle ps_pic_handling,WORD32 i4_total_frame_bits,WORD32 i4_model_updation_hdr_bits,picture_type_e e_pic_type,UWORD8 u1_is_scd,WORD32 i4_last_frm_in_gop)573 void irc_ba_update_cur_frm_consumed_bits(bit_allocation_t *ps_bit_allocation,
574                                          pic_handling_handle ps_pic_handling,
575                                          WORD32 i4_total_frame_bits,
576                                          WORD32 i4_model_updation_hdr_bits,
577                                          picture_type_e e_pic_type,
578                                          UWORD8 u1_is_scd,
579                                          WORD32 i4_last_frm_in_gop)
580 {
581     WORD32 i4_error_bits = irc_get_error_bits(ps_bit_allocation->ps_error_bits);
582 
583     /* Update the remaining bits in period */
584     irc_ba_update_rbip(&ps_bit_allocation->s_rbip, ps_pic_handling,
585                        (-i4_total_frame_bits + i4_error_bits));
586 
587     /*
588      * Update the header bits so that it can be used as an estimate to the next
589      * frame
590      */
591     if(u1_is_scd)
592     {
593         /*
594          * In case of SCD, even though the frame type is P, it is equivalent to
595          * a I frame and so the corresponding header bits is updated
596          */
597         ps_bit_allocation->i4_prev_frm_header_bits[I_PIC] =
598                         i4_model_updation_hdr_bits;
599 
600 #define MAX_NUM_GOPS_IN_PERIOD (3)
601         if(ps_bit_allocation->i4_num_gops_in_period < MAX_NUM_GOPS_IN_PERIOD)
602         {
603             /*
604              * Whenever there is a scene change increase the number of gops by
605              * 2 so that the number of bits allocated is not very constrained
606              */
607             ps_bit_allocation->i4_num_gops_in_period += 2;
608             /* Add the extra bits in GOP to remaining bits in period */
609             irc_ba_change_rbip(&ps_bit_allocation->s_rbip, ps_pic_handling,
610                                ps_bit_allocation->i4_bits_per_frm,
611                                ps_bit_allocation->i4_num_gops_in_period);
612         }
613     }
614     else
615     {
616         ps_bit_allocation->i4_prev_frm_header_bits[e_pic_type] =
617                         i4_model_updation_hdr_bits;
618     }
619 
620     if(i4_last_frm_in_gop)
621     {
622         WORD32 i4_num_bits_in_a_gop = get_number_of_frms_in_a_gop(
623                         ps_pic_handling) * ps_bit_allocation->i4_bits_per_frm;
624         /*
625          * If the number of gops in period has been increased due to scene
626          * change, slowly bring in down across the gops
627          */
628         if(ps_bit_allocation->i4_num_gops_in_period
629                         > ps_bit_allocation->i4_actual_num_gops_in_period)
630         {
631             ps_bit_allocation->i4_num_gops_in_period--;
632             irc_ba_change_rbip(&ps_bit_allocation->s_rbip, ps_pic_handling,
633                                ps_bit_allocation->i4_bits_per_frm,
634                                ps_bit_allocation->i4_num_gops_in_period);
635         }
636         /*
637          * If rem_bits_in_period < 0 decrease the number of bits allocated for
638          * the next period else increase it
639          */
640         irc_ba_update_rbip(&ps_bit_allocation->s_rbip, ps_pic_handling,
641                            i4_num_bits_in_a_gop);
642     }
643     /* Update the lower modules */
644     irc_update_error_bits(ps_bit_allocation->ps_error_bits);
645 }
646 
irc_ba_change_remaining_bits_in_period(bit_allocation_t * ps_bit_allocation,pic_handling_handle ps_pic_handling,WORD32 i4_bit_rate,WORD32 i4_frame_rate,WORD32 * i4_peak_bit_rate)647 void irc_ba_change_remaining_bits_in_period(bit_allocation_t *ps_bit_allocation,
648                                             pic_handling_handle ps_pic_handling,
649                                             WORD32 i4_bit_rate,
650                                             WORD32 i4_frame_rate,
651                                             WORD32 *i4_peak_bit_rate)
652 {
653     WORD32 i4_new_avg_bits_per_frm;
654     WORD32 i4_new_peak_bits_per_frm[MAX_NUM_DRAIN_RATES];
655     WORD32 i4_rem_frms_in_period[MAX_PIC_TYPE];
656     int i;
657 
658     /* Calculate the new per frame bits */
659     X_PROD_Y_DIV_Z(i4_bit_rate, 1000, i4_frame_rate, i4_new_avg_bits_per_frm);
660     for(i = 0; i < MAX_NUM_DRAIN_RATES; i++)
661     {
662         X_PROD_Y_DIV_Z(i4_peak_bit_rate[i], 1000, i4_frame_rate,
663                        i4_new_peak_bits_per_frm[i]);
664     }
665 
666     for(i = 0; i < MAX_NUM_DRAIN_RATES; i++)
667     {
668         ps_bit_allocation->i4_max_bits_per_frm[i] = i4_new_peak_bits_per_frm[i];
669     }
670 
671     /*
672      * Get the rem_frms_in_prd & the frms_in_prd from the pic_type state
673      * struct
674      */
675     irc_pic_type_get_rem_frms_in_gop(ps_pic_handling, i4_rem_frms_in_period);
676 
677     /*
678      * If the difference > 0(/ <0), the remaining bits in period needs to be
679      * increased(/decreased) based on the remaining number of frames
680      */
681     irc_ba_change_rbip(&ps_bit_allocation->s_rbip, ps_pic_handling,
682                        i4_new_avg_bits_per_frm,
683                        ps_bit_allocation->i4_num_gops_in_period);
684 
685     /* Update the new average bits per frame */
686     ps_bit_allocation->i4_bits_per_frm = i4_new_avg_bits_per_frm;
687     /* change the lower modules state */
688     irc_change_bitrate_in_error_bits(ps_bit_allocation->ps_error_bits,
689                                      i4_bit_rate);
690     irc_change_frm_rate_in_error_bits(ps_bit_allocation->ps_error_bits,
691                                       i4_frame_rate);
692 
693     /* Store the modified frame_rate */
694     ps_bit_allocation->i4_frame_rate = i4_frame_rate;
695     ps_bit_allocation->i4_bit_rate = i4_bit_rate;
696     for(i = 0; i < MAX_NUM_DRAIN_RATES; i++)
697         ps_bit_allocation->ai4_peak_bit_rate[i] = i4_peak_bit_rate[i];
698 }
699 
irc_ba_change_ba_peak_bit_rate(bit_allocation_t * ps_bit_allocation,WORD32 * ai4_peak_bit_rate)700 void irc_ba_change_ba_peak_bit_rate(bit_allocation_t *ps_bit_allocation,
701                                     WORD32 *ai4_peak_bit_rate)
702 {
703     WORD32 i;
704 
705     /* Calculate the bits per frame */
706     for(i = 0; i < MAX_NUM_DRAIN_RATES; i++)
707     {
708         X_PROD_Y_DIV_Z(ai4_peak_bit_rate[i], 1000,
709                        ps_bit_allocation->i4_frame_rate,
710                        ps_bit_allocation->i4_max_bits_per_frm[i]);
711         ps_bit_allocation->ai4_peak_bit_rate[i] = ai4_peak_bit_rate[i];
712     }
713 }
714 
715 /******************************************************************************
716  * @brief Modifies the remaining bit in period for the gop which has fif.
717  *      since fif would cause a new gop to be created, we need to add the number
718  *      of encoded frames in the fif GOP worth of bits to remaining bits in
719  *      period
720  ******************************************************************************/
irc_ba_change_rem_bits_in_prd_at_force_I_frame(bit_allocation_t * ps_bit_allocation,pic_handling_handle ps_pic_handling)721 void irc_ba_change_rem_bits_in_prd_at_force_I_frame(bit_allocation_t *ps_bit_allocation,
722                                                     pic_handling_handle ps_pic_handling)
723 {
724     WORD32 i4_frms_in_period;
725     i4_frms_in_period = irc_pic_type_get_frms_in_gop_force_I_frm(
726                     ps_pic_handling);
727     irc_ba_update_rbip(&ps_bit_allocation->s_rbip, ps_pic_handling,
728                        ps_bit_allocation->i4_bits_per_frm * i4_frms_in_period);
729 }
730 
irc_ba_check_and_update_bit_allocation(bit_allocation_t * ps_bit_allocation,pic_handling_handle ps_pic_handling,WORD32 i4_cur_buf_size,WORD32 i4_max_buf_size,WORD32 i4_max_bits_inflow_per_frm,WORD32 i4_tot_frame_bits)731 void irc_ba_check_and_update_bit_allocation(bit_allocation_t *ps_bit_allocation,
732                                             pic_handling_handle ps_pic_handling,
733                                             WORD32 i4_cur_buf_size,
734                                             WORD32 i4_max_buf_size,
735                                             WORD32 i4_max_bits_inflow_per_frm,
736                                             WORD32 i4_tot_frame_bits)
737 {
738 
739     number_t vq_max_drain_bits, vq_extra_bits, vq_less_bits,
740                     vq_allocated_saved_bits, vq_min_bits_for_period;
741     WORD32 i4_num_frms_in_period = get_number_of_frms_in_a_gop(ps_pic_handling);
742     number_t vq_rem_bits_in_period, vq_num_frms_in_period, vq_zero;
743     WORD32 b_rem_bits_gt_max_drain, b_rem_bits_lt_min_bits,
744                     b_saved_bits_gt_zero;
745     rem_bit_in_prd_t *ps_rbip = &ps_bit_allocation->s_rbip;
746 
747     UNUSED(i4_cur_buf_size);
748     UNUSED(i4_max_buf_size);
749     UNUSED(i4_tot_frame_bits);
750 
751     /*
752      * If the remaining bits is greater than what can be drained in that period
753      * Clip the remaining bits in period to the maximum it can drain in that
754      * period with the error of current buffer size.Accumulate the saved bits
755      * if any. else if the remaining bits is lesser than the minimum bit rate
756      * promised in that period Add the excess bits to remaining bits in period
757      * and reduce it from the saved bits Else Provide the extra bits from the
758      * "saved bits pool".
759      */
760     /*
761      * max_drain_bits = num_gops_in_period * num_frms_in_period *
762      * * max_bits_inflow_per_frm
763      */
764     SET_VAR_Q(vq_num_frms_in_period,
765               (ps_bit_allocation->i4_num_gops_in_period * i4_num_frms_in_period),
766               0);
767     SET_VAR_Q(vq_max_drain_bits, i4_max_bits_inflow_per_frm, 0);
768     SET_VAR_Q(vq_zero, 0, 0);
769     mult32_var_q(vq_max_drain_bits, vq_num_frms_in_period, &vq_max_drain_bits);
770 
771     /*
772      * min_bits_for_period = num_gops_in_period * num_frms_in_period *
773      * min_bits_per_frm
774      */
775     SET_VAR_Q(vq_min_bits_for_period, ps_bit_allocation->i4_min_bits_per_frm,
776               0);
777     mult32_var_q(vq_min_bits_for_period, vq_num_frms_in_period,
778                  &vq_min_bits_for_period);
779 
780     vq_rem_bits_in_period = ps_rbip->vq_rem_bits_in_period;
781 
782     /* Evaluate rem_bits_in_period  > max_drain_bits      */
783     VQ_A_GT_VQ_B(ps_rbip->vq_rem_bits_in_period, vq_max_drain_bits,
784                  b_rem_bits_gt_max_drain);
785 
786     /* Evaluate rem_bits_in_period  < min_bits_for_period */
787     VQ_A_LT_VQ_B(ps_rbip->vq_rem_bits_in_period, vq_min_bits_for_period,
788                  b_rem_bits_lt_min_bits);
789 
790     /* Evaluate saved_bits  > 0 */
791     VQ_A_LT_VQ_B(ps_bit_allocation->vq_saved_bits, vq_zero,
792                  b_saved_bits_gt_zero);
793 
794     /* (i4_rem_bits_in_period > i4_max_drain_bits) */
795     if(b_rem_bits_gt_max_drain)
796     {
797         /* extra_bits = rem_bits_in_period - max_drain_bits */
798         sub32_var_q(ps_rbip->vq_rem_bits_in_period, vq_max_drain_bits,
799                     &vq_extra_bits);
800 
801         /* saved_bits += extra_bits */
802         add32_var_q(ps_bit_allocation->vq_saved_bits, vq_extra_bits,
803                     &ps_bit_allocation->vq_saved_bits);
804 
805         /* rem_bits_in_period = vq_max_drain_bits */
806         ps_rbip->vq_rem_bits_in_period = vq_max_drain_bits;
807     }
808     else if(b_rem_bits_lt_min_bits)
809     {
810         /* extra_bits(-ve) =  rem_bits_in_period - i4_min_bits_for_period */
811         sub32_var_q(ps_rbip->vq_rem_bits_in_period, vq_min_bits_for_period,
812                     &vq_extra_bits);
813 
814         /* saved_bits += extra_bits(-ve) */
815         add32_var_q(ps_bit_allocation->vq_saved_bits, vq_extra_bits,
816                     &ps_bit_allocation->vq_saved_bits);
817 
818         /* rem_bits_in_period = min_bits_for_period */
819         ps_rbip->vq_rem_bits_in_period = vq_min_bits_for_period;
820     }
821     else if(b_saved_bits_gt_zero)
822     {
823         /* less_bits = max_drain_bits - _rem_bits_in_period */
824         sub32_var_q(vq_max_drain_bits, vq_rem_bits_in_period, &vq_less_bits);
825 
826         /* allocated_saved_bits = MIN (less_bits, saved_bits) */
827         MIN_VARQ(ps_bit_allocation->vq_saved_bits, vq_less_bits,
828                  vq_allocated_saved_bits);
829 
830         /* rem_bits_in_period += allocted_save_bits */
831         add32_var_q(ps_rbip->vq_rem_bits_in_period, vq_allocated_saved_bits,
832                     &ps_rbip->vq_rem_bits_in_period);
833 
834         /* saved_bits -= allocted_save_bits */
835         sub32_var_q(ps_bit_allocation->vq_saved_bits, vq_allocated_saved_bits,
836                     &ps_bit_allocation->vq_saved_bits);
837     }
838     return;
839 }
840 
irc_ba_get_frame_rate(bit_allocation_t * ps_bit_allocation)841 WORD32 irc_ba_get_frame_rate(bit_allocation_t *ps_bit_allocation)
842 {
843     return (ps_bit_allocation->i4_frame_rate);
844 }
845 
irc_ba_get_bit_rate(bit_allocation_t * ps_bit_allocation)846 WORD32 irc_ba_get_bit_rate(bit_allocation_t *ps_bit_allocation)
847 {
848     return (ps_bit_allocation->i4_bit_rate);
849 }
850 
irc_ba_get_peak_bit_rate(bit_allocation_t * ps_bit_allocation,WORD32 * pi4_peak_bit_rate)851 void irc_ba_get_peak_bit_rate(bit_allocation_t *ps_bit_allocation,
852                               WORD32 *pi4_peak_bit_rate)
853 {
854     WORD32 i;
855     for(i = 0; i < MAX_NUM_DRAIN_RATES; i++)
856     {
857         pi4_peak_bit_rate[i] = ps_bit_allocation->ai4_peak_bit_rate[i];
858     }
859 }
860