Hamsalekha S | 8d3d303 | 2015-03-13 21:24:58 +0530 | [diff] [blame] | 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 | /*****************************************************************************/ |
| 22 | /* File Includes */ |
| 23 | /*****************************************************************************/ |
| 24 | |
| 25 | /* System include files */ |
| 26 | #include <stdio.h> |
| 27 | |
| 28 | /* User include files */ |
| 29 | #include "irc_datatypes.h" |
| 30 | #include "irc_cntrl_param.h" |
| 31 | #include "irc_common.h" |
| 32 | #include "irc_mem_req_and_acq.h" |
| 33 | #include "irc_fixed_point_error_bits.h" |
| 34 | #include "irc_cbr_buffer_control.h" |
| 35 | #include "irc_trace_support.h" |
| 36 | |
| 37 | typedef struct cbr_buffer_t |
| 38 | { |
| 39 | /* Buffer size = Delay * Bitrate*/ |
| 40 | WORD32 i4_buffer_size; |
| 41 | |
| 42 | /* Constant drain rate */ |
| 43 | WORD32 i4_drain_bits_per_frame[MAX_NUM_DRAIN_RATES]; |
| 44 | |
| 45 | /* Encoder Buffer Fullness */ |
| 46 | WORD32 i4_ebf; |
| 47 | |
| 48 | /* Upper threshold of the Buffer */ |
| 49 | WORD32 i4_upr_thr[MAX_PIC_TYPE]; |
| 50 | |
| 51 | /* Lower threshold of the Buffer */ |
| 52 | WORD32 i4_low_thr[MAX_PIC_TYPE]; |
| 53 | |
| 54 | /* Stuffing threshold equal to error bits per second in the drain bits |
| 55 | * fixed point computation */ |
| 56 | WORD32 i4_stuffing_threshold; |
| 57 | |
| 58 | /* For error due to bits per frame calculation */ |
| 59 | error_bits_handle aps_bpf_error_bits[MAX_NUM_DRAIN_RATES]; |
| 60 | |
| 61 | /* Whether the buffer model is used for CBR or VBR streaming */ |
| 62 | WORD32 i4_is_cbr_mode; |
| 63 | |
| 64 | /* Input parameters stored for initialization */ |
| 65 | WORD32 ai4_bit_rate[MAX_NUM_DRAIN_RATES]; |
| 66 | |
| 67 | WORD32 i4_max_delay; |
| 68 | |
| 69 | WORD32 ai4_num_pics_in_delay_period[MAX_PIC_TYPE]; |
| 70 | |
| 71 | WORD32 i4_tgt_frm_rate; |
| 72 | |
| 73 | UWORD32 u4_max_vbv_buf_size; |
| 74 | |
| 75 | } cbr_buffer_t; |
| 76 | |
| 77 | WORD32 irc_cbr_buffer_num_fill_use_free_memtab(cbr_buffer_t **pps_cbr_buffer, |
| 78 | itt_memtab_t *ps_memtab, |
| 79 | ITT_FUNC_TYPE_E e_func_type) |
| 80 | { |
| 81 | WORD32 i4_mem_tab_idx = 0, i; |
Martin Storsjo | 7313602 | 2015-06-23 14:51:06 +0300 | [diff] [blame] | 82 | cbr_buffer_t s_cbr_buffer_temp; |
Hamsalekha S | 8d3d303 | 2015-03-13 21:24:58 +0530 | [diff] [blame] | 83 | |
| 84 | /* |
| 85 | * Hack for all alloc, during which we don't have any state memory. |
| 86 | * Dereferencing can cause issues |
| 87 | */ |
| 88 | if(e_func_type == GET_NUM_MEMTAB || e_func_type == FILL_MEMTAB) |
| 89 | (*pps_cbr_buffer) = &s_cbr_buffer_temp; |
| 90 | |
| 91 | if(e_func_type != GET_NUM_MEMTAB) |
| 92 | { |
| 93 | fill_memtab(&ps_memtab[i4_mem_tab_idx], sizeof(cbr_buffer_t), |
| 94 | ALIGN_128_BYTE, PERSISTENT, DDR); |
| 95 | use_or_fill_base(&ps_memtab[0], (void**)pps_cbr_buffer, e_func_type); |
| 96 | } |
| 97 | i4_mem_tab_idx++; |
| 98 | |
| 99 | for(i = 0; i < MAX_NUM_DRAIN_RATES; i++) |
| 100 | { |
| 101 | i4_mem_tab_idx += irc_error_bits_num_fill_use_free_memtab( |
| 102 | &pps_cbr_buffer[0]->aps_bpf_error_bits[i], |
| 103 | &ps_memtab[i4_mem_tab_idx], e_func_type); |
| 104 | } |
| 105 | return (i4_mem_tab_idx); |
| 106 | } |
| 107 | |
| 108 | /****************************************************************************** |
| 109 | * @brief Initialize the CBR VBV buffer state. |
| 110 | * This could however be used for VBR streaming VBV also |
| 111 | * |
| 112 | ******************************************************************************/ |
| 113 | void irc_init_cbr_buffer(cbr_buffer_t *ps_cbr_buffer, |
| 114 | WORD32 i4_buffer_delay, |
| 115 | WORD32 i4_tgt_frm_rate, |
| 116 | WORD32 *i4_bit_rate, |
| 117 | UWORD32 *u4_num_pics_in_delay_prd, |
| 118 | UWORD32 u4_vbv_buf_size) |
| 119 | { |
| 120 | WORD32 i4_i, i4_bits_per_frm[MAX_NUM_DRAIN_RATES]; |
| 121 | int i; |
| 122 | |
| 123 | for(i = 0; i < MAX_NUM_DRAIN_RATES; i++) |
| 124 | { |
| 125 | X_PROD_Y_DIV_Z(i4_bit_rate[i], 1000, i4_tgt_frm_rate, |
| 126 | i4_bits_per_frm[i]); |
| 127 | /* Drain rate = bitrate/(framerate/1000) */ |
| 128 | ps_cbr_buffer->i4_drain_bits_per_frame[i] = i4_bits_per_frm[i]; |
| 129 | /* Initialize the bits per frame error bits calculation */ |
| 130 | irc_init_error_bits(ps_cbr_buffer->aps_bpf_error_bits[i], |
| 131 | i4_tgt_frm_rate, i4_bit_rate[i]); |
| 132 | } |
| 133 | |
| 134 | /* Bitrate * delay = buffer size, divide by 1000 as delay is in ms*/ |
| 135 | /* This would mean CBR mode */ |
| 136 | if(i4_bit_rate[0] == i4_bit_rate[1]) |
| 137 | { |
| 138 | X_PROD_Y_DIV_Z(i4_bit_rate[0], i4_buffer_delay, 1000, |
| 139 | ps_cbr_buffer->i4_buffer_size); |
| 140 | ps_cbr_buffer->i4_is_cbr_mode = 1; |
| 141 | } |
| 142 | else |
| 143 | { |
| 144 | /* VBR streaming case which has different drain rates for I and P */ |
| 145 | ps_cbr_buffer->i4_buffer_size = u4_num_pics_in_delay_prd[0] |
| 146 | * ps_cbr_buffer->i4_drain_bits_per_frame[0] |
| 147 | + u4_num_pics_in_delay_prd[1] |
| 148 | * ps_cbr_buffer->i4_drain_bits_per_frame[1]; |
| 149 | |
| 150 | ps_cbr_buffer->i4_is_cbr_mode = 0; |
| 151 | } |
| 152 | |
| 153 | if(ps_cbr_buffer->i4_buffer_size > (WORD32)u4_vbv_buf_size) |
| 154 | { |
| 155 | ps_cbr_buffer->i4_buffer_size = u4_vbv_buf_size; |
| 156 | } |
| 157 | |
| 158 | /* Initially Encoder buffer fullness is zero */ |
| 159 | ps_cbr_buffer->i4_ebf = 0; |
| 160 | |
| 161 | /* tgt_frame_rate is divided by 1000 because, an approximate value is fine |
| 162 | * as this is just a threshold below which stuffing is done to avoid buffer |
| 163 | * underflow due to fixed point error in drain rate |
| 164 | */ |
| 165 | ps_cbr_buffer->i4_stuffing_threshold = (i4_bit_rate[0] |
| 166 | - (i4_bits_per_frm[0] * (i4_tgt_frm_rate / 1000))); |
| 167 | |
| 168 | for(i4_i = 0; i4_i < MAX_PIC_TYPE; i4_i++) |
| 169 | { |
| 170 | /* |
| 171 | * Upper threshold for |
| 172 | * I frame = 1 * bits per frame |
| 173 | * P Frame = 4 * bits per frame. |
| 174 | * The threshold for I frame is only 1 * bits per frame as the threshold |
| 175 | * should only account for error in estimated bits. |
| 176 | * In P frame it should account for difference bets bits consumed by |
| 177 | * I(Scene change) and P frame I to P complexity is assumed to be 5. |
| 178 | */ |
| 179 | WORD32 i4_index; |
| 180 | i4_index = i4_i > 0 ? 1 : 0; |
| 181 | ps_cbr_buffer->i4_upr_thr[i4_i] = ps_cbr_buffer->i4_buffer_size |
| 182 | - (ps_cbr_buffer->i4_buffer_size >> 3); |
| 183 | |
| 184 | /* |
| 185 | * For both I and P frame Lower threshold is equal to drain rate.Even if |
| 186 | * the encoder consumes zero bits it should have enough bits to drain |
| 187 | */ |
| 188 | ps_cbr_buffer->i4_low_thr[i4_i] = i4_bits_per_frm[i4_index]; |
| 189 | } |
| 190 | |
| 191 | /* Storing the input parameters for using it for change functions */ |
| 192 | for(i = 0; i < MAX_NUM_DRAIN_RATES; i++) |
| 193 | { |
| 194 | ps_cbr_buffer->ai4_bit_rate[i] = i4_bit_rate[i]; |
| 195 | } |
| 196 | |
| 197 | for(i = 0; i < MAX_PIC_TYPE; i++) |
| 198 | { |
| 199 | ps_cbr_buffer->ai4_num_pics_in_delay_period[i] = |
| 200 | u4_num_pics_in_delay_prd[i]; |
| 201 | } |
| 202 | ps_cbr_buffer->i4_tgt_frm_rate = i4_tgt_frm_rate; |
| 203 | ps_cbr_buffer->i4_max_delay = i4_buffer_delay; |
| 204 | ps_cbr_buffer->u4_max_vbv_buf_size = u4_vbv_buf_size; |
| 205 | } |
| 206 | |
| 207 | /****************************************************************************** |
| 208 | * @brief Condition check for constraining the number of bits allocated based on |
| 209 | * bufer size |
| 210 | ******************************************************************************/ |
| 211 | WORD32 irc_cbr_buffer_constraint_check(cbr_buffer_t *ps_cbr_buffer, |
| 212 | WORD32 i4_tgt_bits, |
| 213 | picture_type_e e_pic_type) |
| 214 | { |
| 215 | WORD32 i4_max_tgt_bits, i4_min_tgt_bits; |
| 216 | WORD32 i4_drain_bits_per_frame = (e_pic_type == I_PIC) ? |
| 217 | ps_cbr_buffer->i4_drain_bits_per_frame[0] : |
| 218 | ps_cbr_buffer->i4_drain_bits_per_frame[1]; |
| 219 | |
| 220 | /* Max tgt bits = Upper threshold - current encoder buffer fullness */ |
| 221 | i4_max_tgt_bits = ps_cbr_buffer->i4_upr_thr[e_pic_type] |
| 222 | - ps_cbr_buffer->i4_ebf; |
| 223 | /* Max tgt bits cannot be negative */ |
| 224 | if(i4_max_tgt_bits < 0) |
| 225 | i4_max_tgt_bits = 0; |
| 226 | |
| 227 | /* |
| 228 | * Min tgt bits , least number of bits in the Encoder after |
| 229 | * draining such that it is greater than lower threshold |
| 230 | */ |
| 231 | i4_min_tgt_bits = ps_cbr_buffer->i4_low_thr[e_pic_type] |
| 232 | - (ps_cbr_buffer->i4_ebf - i4_drain_bits_per_frame); |
| 233 | /* Min tgt bits cannot be negative */ |
| 234 | if(i4_min_tgt_bits < 0) |
| 235 | i4_min_tgt_bits = 0; |
| 236 | |
| 237 | /* Current tgt bits should be between max and min tgt bits */ |
| 238 | CLIP(i4_tgt_bits, i4_max_tgt_bits, i4_min_tgt_bits); |
| 239 | return i4_tgt_bits; |
| 240 | } |
| 241 | |
| 242 | /* ***************************************************************************** |
| 243 | * @brief constaints the bit allocation based on buffer size |
| 244 | * |
| 245 | ******************************************************************************/ |
| 246 | WORD32 irc_vbr_stream_buffer_constraint_check(cbr_buffer_t *ps_cbr_buffer, |
| 247 | WORD32 i4_tgt_bits, |
| 248 | picture_type_e e_pic_type) |
| 249 | { |
| 250 | WORD32 i4_max_tgt_bits; |
| 251 | |
| 252 | /* Max tgt bits = Upper threshold - current encoder buffer fullness */ |
| 253 | i4_max_tgt_bits = ps_cbr_buffer->i4_upr_thr[e_pic_type] |
| 254 | - ps_cbr_buffer->i4_ebf; |
| 255 | |
| 256 | /* Max tgt bits cannot be negative */ |
| 257 | if(i4_max_tgt_bits < 0) |
| 258 | i4_max_tgt_bits = 0; |
| 259 | |
| 260 | if(i4_tgt_bits > i4_max_tgt_bits) |
| 261 | i4_tgt_bits = i4_max_tgt_bits; |
| 262 | |
| 263 | return i4_tgt_bits; |
| 264 | } |
| 265 | |
| 266 | /* ***************************************************************************** |
| 267 | * @brief Verifies the buffer state and returns whether it is overflowing, |
| 268 | * underflowing or normal |
| 269 | * |
| 270 | ******************************************************************************/ |
| 271 | vbv_buf_status_e irc_get_cbr_buffer_status(cbr_buffer_t *ps_cbr_buffer, |
| 272 | WORD32 i4_tot_consumed_bits, |
| 273 | WORD32 *pi4_num_bits_to_prevent_overflow, |
| 274 | picture_type_e e_pic_type) |
| 275 | { |
| 276 | vbv_buf_status_e e_buf_status; |
| 277 | WORD32 i4_cur_enc_buf; |
| 278 | WORD32 i4_error_bits = (e_pic_type == I_PIC) ? |
| 279 | irc_get_error_bits(ps_cbr_buffer |
| 280 | ->aps_bpf_error_bits[0]) : |
| 281 | irc_get_error_bits(ps_cbr_buffer |
| 282 | ->aps_bpf_error_bits[1]); |
| 283 | |
| 284 | WORD32 i4_drain_bits_per_frame = (e_pic_type == I_PIC) ? |
| 285 | ps_cbr_buffer->i4_drain_bits_per_frame[0] : |
| 286 | ps_cbr_buffer->i4_drain_bits_per_frame[1]; |
| 287 | |
| 288 | /* Add the tot consumed bits to the Encoder Buffer*/ |
| 289 | i4_cur_enc_buf = ps_cbr_buffer->i4_ebf + i4_tot_consumed_bits; |
| 290 | |
| 291 | /* If the Encoder exceeds the Buffer Size signal an Overflow*/ |
| 292 | if(i4_cur_enc_buf > ps_cbr_buffer->i4_buffer_size) |
| 293 | { |
| 294 | e_buf_status = VBV_OVERFLOW; |
| 295 | i4_cur_enc_buf = ps_cbr_buffer->i4_buffer_size; |
| 296 | } |
| 297 | else |
| 298 | { |
| 299 | /* |
| 300 | * Subtract the constant drain bits and error bits due to fixed point |
| 301 | * implementation |
| 302 | */ |
| 303 | i4_cur_enc_buf -= (i4_drain_bits_per_frame + i4_error_bits); |
| 304 | |
| 305 | /* |
| 306 | * If the buffer is less than stuffing threshold an Underflow is |
| 307 | * signaled else its NORMAL |
| 308 | */ |
| 309 | if(i4_cur_enc_buf < ps_cbr_buffer->i4_stuffing_threshold) |
| 310 | { |
| 311 | e_buf_status = VBV_UNDERFLOW; |
| 312 | } |
| 313 | else |
| 314 | { |
| 315 | e_buf_status = VBV_NORMAL; |
| 316 | } |
| 317 | |
| 318 | if(i4_cur_enc_buf < 0) |
| 319 | i4_cur_enc_buf = 0; |
| 320 | } |
| 321 | |
| 322 | /* |
| 323 | * The RC lib models the encoder buffer, but the VBV buffer characterizes |
| 324 | * the decoder buffer |
| 325 | */ |
| 326 | if(e_buf_status == VBV_OVERFLOW) |
| 327 | { |
| 328 | e_buf_status = VBV_UNDERFLOW; |
| 329 | } |
| 330 | else if(e_buf_status == VBV_UNDERFLOW) |
| 331 | { |
| 332 | e_buf_status = VBV_OVERFLOW; |
| 333 | } |
| 334 | |
| 335 | pi4_num_bits_to_prevent_overflow[0] = (ps_cbr_buffer->i4_buffer_size |
| 336 | - i4_cur_enc_buf); |
| 337 | |
| 338 | return e_buf_status; |
| 339 | } |
| 340 | |
| 341 | /******************************************************************************* |
| 342 | * @brief Based on the bits consumed the buffer model is updated |
| 343 | ******************************************************************************/ |
| 344 | void irc_update_cbr_buffer(cbr_buffer_t *ps_cbr_buffer, |
| 345 | WORD32 i4_tot_consumed_bits, |
| 346 | picture_type_e e_pic_type) |
| 347 | { |
| 348 | WORD32 i4_error_bits = (e_pic_type == I_PIC) ? |
| 349 | irc_get_error_bits(ps_cbr_buffer-> |
| 350 | aps_bpf_error_bits[0]) : |
| 351 | irc_get_error_bits( ps_cbr_buffer-> |
| 352 | aps_bpf_error_bits[1]); |
| 353 | |
| 354 | WORD32 i4_drain_bits_per_frame = (e_pic_type == I_PIC) ? |
| 355 | ps_cbr_buffer->i4_drain_bits_per_frame[0] : |
| 356 | ps_cbr_buffer->i4_drain_bits_per_frame[1]; |
| 357 | |
| 358 | /* Update the Encoder buffer with the total consumed bits*/ |
| 359 | ps_cbr_buffer->i4_ebf += i4_tot_consumed_bits; |
| 360 | |
| 361 | /* |
| 362 | * Subtract the drain bits and error bits due to fixed point |
| 363 | * implementation |
| 364 | */ |
| 365 | ps_cbr_buffer->i4_ebf -= (i4_drain_bits_per_frame + i4_error_bits); |
| 366 | |
| 367 | if(ps_cbr_buffer->i4_ebf < 0) |
| 368 | ps_cbr_buffer->i4_ebf = 0; |
| 369 | |
| 370 | /*SS - Fix for lack of stuffing*/ |
| 371 | if(ps_cbr_buffer->i4_ebf > ps_cbr_buffer->i4_buffer_size) |
| 372 | { |
| 373 | trace_printf( |
| 374 | (const WORD8*)"Error: Should not be coming here with stuffing\n"); |
| 375 | ps_cbr_buffer->i4_ebf = ps_cbr_buffer->i4_buffer_size; |
| 376 | } |
| 377 | } |
| 378 | |
| 379 | /******************************************************************************* |
| 380 | * @brief If the buffer underflows then return the number of bits to prevent |
| 381 | * underflow |
| 382 | * |
| 383 | ******************************************************************************/ |
| 384 | WORD32 irc_get_cbr_bits_to_stuff(cbr_buffer_t *ps_cbr_buffer, |
| 385 | WORD32 i4_tot_consumed_bits, |
| 386 | picture_type_e e_pic_type) |
| 387 | { |
| 388 | WORD32 i4_bits_to_stuff; |
| 389 | WORD32 i4_error_bits = (e_pic_type == I_PIC) ? |
| 390 | irc_get_error_bits(ps_cbr_buffer |
| 391 | ->aps_bpf_error_bits[0]) : |
| 392 | irc_get_error_bits(ps_cbr_buffer |
| 393 | ->aps_bpf_error_bits[1]); |
| 394 | |
| 395 | WORD32 i4_drain_bits_per_frame = (e_pic_type == I_PIC) ? |
| 396 | ps_cbr_buffer->i4_drain_bits_per_frame[0] : |
| 397 | ps_cbr_buffer->i4_drain_bits_per_frame[1]; |
| 398 | |
| 399 | /* |
| 400 | * Stuffing bits got from the following equation |
| 401 | * Stuffing_threshold = ebf + tcb - drain bits - error bits + stuff_bits |
| 402 | */ |
| 403 | i4_bits_to_stuff = i4_drain_bits_per_frame + i4_error_bits |
| 404 | + ps_cbr_buffer->i4_stuffing_threshold |
| 405 | - (ps_cbr_buffer->i4_ebf + i4_tot_consumed_bits); |
| 406 | |
| 407 | return i4_bits_to_stuff; |
| 408 | } |
| 409 | |
| 410 | /******************************************************************************* |
| 411 | * @brief Update the state for change in number of pics in the delay period |
| 412 | * |
| 413 | ******************************************************************************/ |
| 414 | void irc_change_cbr_vbv_num_pics_in_delay_period(cbr_buffer_t *ps_cbr_buffer, |
| 415 | UWORD32 *u4_num_pics_in_delay_prd) |
| 416 | { |
| 417 | WORD32 i; |
| 418 | |
| 419 | if(!ps_cbr_buffer->i4_is_cbr_mode) |
| 420 | { |
| 421 | ps_cbr_buffer->i4_buffer_size = |
| 422 | u4_num_pics_in_delay_prd[0] |
| 423 | * ps_cbr_buffer->i4_drain_bits_per_frame[0] |
| 424 | + u4_num_pics_in_delay_prd[1] |
| 425 | * ps_cbr_buffer->i4_drain_bits_per_frame[1]; |
| 426 | |
| 427 | if(ps_cbr_buffer->i4_buffer_size |
| 428 | > (WORD32)ps_cbr_buffer->u4_max_vbv_buf_size) |
| 429 | { |
| 430 | ps_cbr_buffer->i4_buffer_size = ps_cbr_buffer->u4_max_vbv_buf_size; |
| 431 | } |
| 432 | for(i = 0; i < MAX_PIC_TYPE; i++) |
| 433 | { |
| 434 | ps_cbr_buffer->i4_upr_thr[i] = ps_cbr_buffer->i4_buffer_size |
| 435 | - (ps_cbr_buffer->i4_buffer_size >> 3); |
| 436 | } |
| 437 | |
| 438 | /* Re-initialize the number of pics in delay period */ |
| 439 | for(i = 0; i < MAX_PIC_TYPE; i++) |
| 440 | { |
| 441 | ps_cbr_buffer->ai4_num_pics_in_delay_period[i] = |
| 442 | u4_num_pics_in_delay_prd[i]; |
| 443 | } |
| 444 | } |
| 445 | } |
| 446 | |
| 447 | /****************************************************************************** |
| 448 | * @brief update the state for change in target frame rate |
| 449 | * |
| 450 | ******************************************************************************/ |
| 451 | void irc_change_cbr_vbv_tgt_frame_rate(cbr_buffer_t *ps_cbr_buffer, |
| 452 | WORD32 i4_tgt_frm_rate) |
| 453 | { |
| 454 | WORD32 i4_i, i4_bits_per_frm[MAX_NUM_DRAIN_RATES]; |
| 455 | int i; |
| 456 | |
| 457 | for(i = 0; i < MAX_NUM_DRAIN_RATES; i++) |
| 458 | { |
| 459 | X_PROD_Y_DIV_Z(ps_cbr_buffer->ai4_bit_rate[i], 1000, i4_tgt_frm_rate, |
| 460 | i4_bits_per_frm[i]); |
| 461 | /* Drain rate = bitrate/(framerate/1000) */ |
| 462 | ps_cbr_buffer->i4_drain_bits_per_frame[i] = i4_bits_per_frm[i]; |
| 463 | /* Initialize the bits per frame error bits calculation */ |
| 464 | irc_change_frm_rate_in_error_bits(ps_cbr_buffer->aps_bpf_error_bits[i], |
| 465 | i4_tgt_frm_rate); |
| 466 | } |
| 467 | |
| 468 | /* Bitrate * delay = buffer size, divide by 1000 as delay is in ms*/ |
| 469 | if(!ps_cbr_buffer->i4_is_cbr_mode) |
| 470 | { |
| 471 | /* VBR streaming case which has different drain rates for I and P */ |
| 472 | ps_cbr_buffer->i4_buffer_size = |
| 473 | ps_cbr_buffer->ai4_num_pics_in_delay_period[0] |
| 474 | * ps_cbr_buffer->i4_drain_bits_per_frame[0] |
| 475 | + ps_cbr_buffer->ai4_num_pics_in_delay_period[1] |
| 476 | * ps_cbr_buffer->i4_drain_bits_per_frame[1]; |
| 477 | } |
| 478 | |
| 479 | if(ps_cbr_buffer->i4_buffer_size |
| 480 | > (WORD32)ps_cbr_buffer->u4_max_vbv_buf_size) |
| 481 | { |
| 482 | ps_cbr_buffer->i4_buffer_size = ps_cbr_buffer->u4_max_vbv_buf_size; |
| 483 | } |
| 484 | |
| 485 | /* |
| 486 | * Tgt_frame_rate is divided by 1000 because an approximate value is fine as |
| 487 | * this is just a threshold below which stuffing is done to avoid buffer |
| 488 | * underflow due to fixed point error in drain rate |
| 489 | */ |
| 490 | ps_cbr_buffer->i4_stuffing_threshold = (ps_cbr_buffer->ai4_bit_rate[0] |
| 491 | - (i4_bits_per_frm[0] * (i4_tgt_frm_rate / 1000))); |
| 492 | |
| 493 | for(i4_i = 0; i4_i < MAX_PIC_TYPE; i4_i++) |
| 494 | { |
| 495 | /* |
| 496 | * Upper threshold for |
| 497 | * I frame = 1 * bits per frame |
| 498 | * P Frame = 4 * bits per frame. |
| 499 | * The threshold for I frame is only 1 * bits per frame as the threshold should |
| 500 | * only account for error in estimated bits. |
| 501 | * In P frame it should account for difference bets bits consumed by I(Scene change) |
| 502 | * and P frame I to P complexity is assumed to be 5. |
| 503 | */ |
| 504 | WORD32 i4_index; |
| 505 | i4_index = i4_i > 0 ? 1 : 0; |
| 506 | ps_cbr_buffer->i4_upr_thr[i4_i] = ps_cbr_buffer->i4_buffer_size |
| 507 | - (ps_cbr_buffer->i4_buffer_size >> 3); |
| 508 | |
| 509 | /* |
| 510 | * For both I and P frame Lower threshold is equal to drain rate. |
| 511 | * Even if the encoder consumes zero bits it should have enough bits to |
| 512 | * drain |
| 513 | */ |
| 514 | ps_cbr_buffer->i4_low_thr[i4_i] = i4_bits_per_frm[i4_index]; |
| 515 | } |
| 516 | |
| 517 | /* Storing the input parameters for using it for change functions */ |
| 518 | ps_cbr_buffer->i4_tgt_frm_rate = i4_tgt_frm_rate; |
| 519 | } |
| 520 | |
| 521 | /******************************************************************************* |
| 522 | * @brief Change the state for change in bit rate |
| 523 | * |
| 524 | ******************************************************************************/ |
| 525 | void irc_change_cbr_vbv_bit_rate(cbr_buffer_t *ps_cbr_buffer, |
| 526 | WORD32 *i4_bit_rate) |
| 527 | { |
| 528 | WORD32 i4_i, i4_bits_per_frm[MAX_NUM_DRAIN_RATES]; |
| 529 | int i; |
| 530 | |
| 531 | for(i = 0; i < MAX_NUM_DRAIN_RATES; i++) |
| 532 | { |
| 533 | X_PROD_Y_DIV_Z(i4_bit_rate[i], 1000, ps_cbr_buffer->i4_tgt_frm_rate, |
| 534 | i4_bits_per_frm[i]); |
| 535 | /* Drain rate = bitrate/(framerate/1000) */ |
| 536 | ps_cbr_buffer->i4_drain_bits_per_frame[i] = i4_bits_per_frm[i]; |
| 537 | /* Initialize the bits per frame error bits calculation */ |
| 538 | irc_change_bitrate_in_error_bits(ps_cbr_buffer->aps_bpf_error_bits[i], |
| 539 | i4_bit_rate[i]); |
| 540 | } |
| 541 | |
| 542 | /* Bitrate * delay = buffer size, divide by 1000 as delay is in ms*/ |
| 543 | if(i4_bit_rate[0] == i4_bit_rate[1]) /* This would mean CBR mode */ |
| 544 | { |
| 545 | X_PROD_Y_DIV_Z(i4_bit_rate[0], ps_cbr_buffer->i4_max_delay, 1000, |
| 546 | ps_cbr_buffer->i4_buffer_size); |
| 547 | ps_cbr_buffer->i4_is_cbr_mode = 1; |
| 548 | } |
| 549 | else |
| 550 | { |
| 551 | /* VBR streaming case which has different drain rates for I and P */ |
| 552 | ps_cbr_buffer->i4_buffer_size = |
| 553 | ps_cbr_buffer->ai4_num_pics_in_delay_period[0] |
| 554 | * ps_cbr_buffer->i4_drain_bits_per_frame[0] |
| 555 | + ps_cbr_buffer->ai4_num_pics_in_delay_period[1] |
| 556 | * ps_cbr_buffer->i4_drain_bits_per_frame[1]; |
| 557 | |
| 558 | ps_cbr_buffer->i4_is_cbr_mode = 0; |
| 559 | } |
| 560 | |
| 561 | if(ps_cbr_buffer->i4_buffer_size |
| 562 | > (WORD32)ps_cbr_buffer->u4_max_vbv_buf_size) |
| 563 | { |
| 564 | ps_cbr_buffer->i4_buffer_size = ps_cbr_buffer->u4_max_vbv_buf_size; |
| 565 | } |
| 566 | |
| 567 | /* |
| 568 | * tgt_frame_rate is divided by 1000 because |
| 569 | * an approximate value is fine as this is just a threshold below which |
| 570 | * stuffing is done to avoid buffer underflow due to fixed point |
| 571 | * error in drain rate |
| 572 | */ |
| 573 | ps_cbr_buffer->i4_stuffing_threshold = (i4_bit_rate[0] |
| 574 | - (i4_bits_per_frm[0] |
| 575 | * (ps_cbr_buffer->i4_tgt_frm_rate / 1000))); |
| 576 | |
| 577 | for(i4_i = 0; i4_i < MAX_PIC_TYPE; i4_i++) |
| 578 | { |
| 579 | /* |
| 580 | * Upper threshold for |
| 581 | * I frame = 1 * bits per frame |
| 582 | * P Frame = 4 * bits per frame. |
| 583 | * The threshold for I frame is only 1 * bits per frame as the threshold |
| 584 | * should only account for error in estimated bits. |
| 585 | * In P frame it should account for difference bets bits consumed by |
| 586 | * I(Scene change) and P frame I to P complexity is assumed to be 5. |
| 587 | */ |
| 588 | |
| 589 | WORD32 i4_index; |
| 590 | i4_index = i4_i > 0 ? 1 : 0; |
| 591 | ps_cbr_buffer->i4_upr_thr[i4_i] = ps_cbr_buffer->i4_buffer_size |
| 592 | - (ps_cbr_buffer->i4_buffer_size >> 3); |
| 593 | |
| 594 | /* For both I and P frame Lower threshold is equal to drain rate. |
| 595 | * Even if the encoder consumes zero bits it should have enough bits to |
| 596 | * drain |
| 597 | */ |
| 598 | ps_cbr_buffer->i4_low_thr[i4_i] = i4_bits_per_frm[i4_index]; |
| 599 | } |
| 600 | |
| 601 | /* Storing the input parameters for using it for change functions */ |
| 602 | for(i = 0; i < MAX_NUM_DRAIN_RATES; i++) |
| 603 | { |
| 604 | ps_cbr_buffer->ai4_bit_rate[i] = i4_bit_rate[i]; |
| 605 | } |
| 606 | } |
| 607 | |
| 608 | void irc_change_cbr_buffer_delay(cbr_buffer_t *ps_cbr_buffer, |
| 609 | WORD32 i4_buffer_delay) |
| 610 | { |
| 611 | WORD32 i4_i; |
| 612 | |
| 613 | /* Bitrate * delay = buffer size, divide by 1000 as delay is in ms*/ |
| 614 | if(ps_cbr_buffer->i4_is_cbr_mode) |
| 615 | { |
| 616 | X_PROD_Y_DIV_Z(ps_cbr_buffer->ai4_bit_rate[0], i4_buffer_delay, 1000, |
| 617 | ps_cbr_buffer->i4_buffer_size); |
| 618 | } |
| 619 | |
| 620 | if(ps_cbr_buffer->i4_buffer_size |
| 621 | > (WORD32)ps_cbr_buffer->u4_max_vbv_buf_size) |
| 622 | { |
| 623 | ps_cbr_buffer->i4_buffer_size = ps_cbr_buffer->u4_max_vbv_buf_size; |
| 624 | } |
| 625 | |
| 626 | for(i4_i = 0; i4_i < MAX_PIC_TYPE; i4_i++) |
| 627 | { |
| 628 | /* |
| 629 | * Upper threshold for |
| 630 | * I frame = 1 * bits per frame |
| 631 | * P Frame = 4 * bits per frame. |
| 632 | * The threshold for I frame is only 1 * bits per frame as the threshold |
| 633 | * should only account for error in estimated bits. |
| 634 | * In P frame it should account for difference bets bits consumed by I |
| 635 | * (Scene change) and P frame I to P complexity is assumed to be 5. |
| 636 | */ |
| 637 | ps_cbr_buffer->i4_upr_thr[i4_i] = ps_cbr_buffer->i4_buffer_size |
| 638 | - (ps_cbr_buffer->i4_buffer_size >> 3); |
| 639 | } |
| 640 | |
| 641 | /* Storing the input parameters for using it for change functions */ |
| 642 | ps_cbr_buffer->i4_max_delay = i4_buffer_delay; |
| 643 | } |
| 644 | |
| 645 | WORD32 irc_get_cbr_buffer_delay(cbr_buffer_t *ps_cbr_buffer) |
| 646 | { |
| 647 | return (ps_cbr_buffer->i4_max_delay); |
| 648 | } |
| 649 | |
| 650 | WORD32 irc_get_cbr_buffer_size(cbr_buffer_t *ps_cbr_buffer) |
| 651 | { |
| 652 | return (ps_cbr_buffer->i4_buffer_size); |
| 653 | } |