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1// SPDX-License-Identifier: GPL-2.02/*3 * Copyright (C) 2019 Pengutronix, Michael Tretter <kernel@pengutronix.de>4 *5 * Convert NAL units between raw byte sequence payloads (RBSP) and C structs6 *7 * The conversion is defined in "ITU-T Rec. H.264 (04/2017) Advanced video8 * coding for generic audiovisual services". Decoder drivers may use the9 * parser to parse RBSP from encoded streams and configure the hardware, if10 * the hardware is not able to parse RBSP itself. Encoder drivers may use the11 * generator to generate the RBSP for SPS/PPS nal units and add them to the12 * encoded stream if the hardware does not generate the units.13 */14 15#include <linux/kernel.h>16#include <linux/types.h>17#include <linux/string.h>18#include <linux/v4l2-controls.h>19 20#include <linux/device.h>21#include <linux/export.h>22#include <linux/log2.h>23 24#include "nal-h264.h"25#include "nal-rbsp.h"26 27/*28 * See Rec. ITU-T H.264 (04/2017) Table 7-1 - NAL unit type codes, syntax29 * element categories, and NAL unit type classes30 */31enum nal_unit_type {32 SEQUENCE_PARAMETER_SET = 7,33 PICTURE_PARAMETER_SET = 8,34 FILLER_DATA = 12,35};36 37static void nal_h264_write_start_code_prefix(struct rbsp *rbsp)38{39 u8 *p = rbsp->data + DIV_ROUND_UP(rbsp->pos, 8);40 int i = 4;41 42 if (DIV_ROUND_UP(rbsp->pos, 8) + i > rbsp->size) {43 rbsp->error = -EINVAL;44 return;45 }46 47 p[0] = 0x00;48 p[1] = 0x00;49 p[2] = 0x00;50 p[3] = 0x01;51 52 rbsp->pos += i * 8;53}54 55static void nal_h264_read_start_code_prefix(struct rbsp *rbsp)56{57 u8 *p = rbsp->data + DIV_ROUND_UP(rbsp->pos, 8);58 int i = 4;59 60 if (DIV_ROUND_UP(rbsp->pos, 8) + i > rbsp->size) {61 rbsp->error = -EINVAL;62 return;63 }64 65 if (p[0] != 0x00 || p[1] != 0x00 || p[2] != 0x00 || p[3] != 0x01) {66 rbsp->error = -EINVAL;67 return;68 }69 70 rbsp->pos += i * 8;71}72 73static void nal_h264_write_filler_data(struct rbsp *rbsp)74{75 u8 *p = rbsp->data + DIV_ROUND_UP(rbsp->pos, 8);76 int i;77 78 /* Keep 1 byte extra for terminating the NAL unit */79 i = rbsp->size - DIV_ROUND_UP(rbsp->pos, 8) - 1;80 memset(p, 0xff, i);81 rbsp->pos += i * 8;82}83 84static void nal_h264_read_filler_data(struct rbsp *rbsp)85{86 u8 *p = rbsp->data + DIV_ROUND_UP(rbsp->pos, 8);87 88 while (*p == 0xff) {89 if (DIV_ROUND_UP(rbsp->pos, 8) > rbsp->size) {90 rbsp->error = -EINVAL;91 return;92 }93 94 p++;95 rbsp->pos += 8;96 }97}98 99static void nal_h264_rbsp_hrd_parameters(struct rbsp *rbsp,100 struct nal_h264_hrd_parameters *hrd)101{102 unsigned int i;103 104 if (!hrd) {105 rbsp->error = -EINVAL;106 return;107 }108 109 rbsp_uev(rbsp, &hrd->cpb_cnt_minus1);110 rbsp_bits(rbsp, 4, &hrd->bit_rate_scale);111 rbsp_bits(rbsp, 4, &hrd->cpb_size_scale);112 113 for (i = 0; i <= hrd->cpb_cnt_minus1; i++) {114 rbsp_uev(rbsp, &hrd->bit_rate_value_minus1[i]);115 rbsp_uev(rbsp, &hrd->cpb_size_value_minus1[i]);116 rbsp_bit(rbsp, &hrd->cbr_flag[i]);117 }118 119 rbsp_bits(rbsp, 5, &hrd->initial_cpb_removal_delay_length_minus1);120 rbsp_bits(rbsp, 5, &hrd->cpb_removal_delay_length_minus1);121 rbsp_bits(rbsp, 5, &hrd->dpb_output_delay_length_minus1);122 rbsp_bits(rbsp, 5, &hrd->time_offset_length);123}124 125static void nal_h264_rbsp_vui_parameters(struct rbsp *rbsp,126 struct nal_h264_vui_parameters *vui)127{128 if (!vui) {129 rbsp->error = -EINVAL;130 return;131 }132 133 rbsp_bit(rbsp, &vui->aspect_ratio_info_present_flag);134 if (vui->aspect_ratio_info_present_flag) {135 rbsp_bits(rbsp, 8, &vui->aspect_ratio_idc);136 if (vui->aspect_ratio_idc == 255) {137 rbsp_bits(rbsp, 16, &vui->sar_width);138 rbsp_bits(rbsp, 16, &vui->sar_height);139 }140 }141 142 rbsp_bit(rbsp, &vui->overscan_info_present_flag);143 if (vui->overscan_info_present_flag)144 rbsp_bit(rbsp, &vui->overscan_appropriate_flag);145 146 rbsp_bit(rbsp, &vui->video_signal_type_present_flag);147 if (vui->video_signal_type_present_flag) {148 rbsp_bits(rbsp, 3, &vui->video_format);149 rbsp_bit(rbsp, &vui->video_full_range_flag);150 151 rbsp_bit(rbsp, &vui->colour_description_present_flag);152 if (vui->colour_description_present_flag) {153 rbsp_bits(rbsp, 8, &vui->colour_primaries);154 rbsp_bits(rbsp, 8, &vui->transfer_characteristics);155 rbsp_bits(rbsp, 8, &vui->matrix_coefficients);156 }157 }158 159 rbsp_bit(rbsp, &vui->chroma_loc_info_present_flag);160 if (vui->chroma_loc_info_present_flag) {161 rbsp_uev(rbsp, &vui->chroma_sample_loc_type_top_field);162 rbsp_uev(rbsp, &vui->chroma_sample_loc_type_bottom_field);163 }164 165 rbsp_bit(rbsp, &vui->timing_info_present_flag);166 if (vui->timing_info_present_flag) {167 rbsp_bits(rbsp, 32, &vui->num_units_in_tick);168 rbsp_bits(rbsp, 32, &vui->time_scale);169 rbsp_bit(rbsp, &vui->fixed_frame_rate_flag);170 }171 172 rbsp_bit(rbsp, &vui->nal_hrd_parameters_present_flag);173 if (vui->nal_hrd_parameters_present_flag)174 nal_h264_rbsp_hrd_parameters(rbsp, &vui->nal_hrd_parameters);175 176 rbsp_bit(rbsp, &vui->vcl_hrd_parameters_present_flag);177 if (vui->vcl_hrd_parameters_present_flag)178 nal_h264_rbsp_hrd_parameters(rbsp, &vui->vcl_hrd_parameters);179 180 if (vui->nal_hrd_parameters_present_flag ||181 vui->vcl_hrd_parameters_present_flag)182 rbsp_bit(rbsp, &vui->low_delay_hrd_flag);183 184 rbsp_bit(rbsp, &vui->pic_struct_present_flag);185 186 rbsp_bit(rbsp, &vui->bitstream_restriction_flag);187 if (vui->bitstream_restriction_flag) {188 rbsp_bit(rbsp, &vui->motion_vectors_over_pic_boundaries_flag);189 rbsp_uev(rbsp, &vui->max_bytes_per_pic_denom);190 rbsp_uev(rbsp, &vui->max_bits_per_mb_denom);191 rbsp_uev(rbsp, &vui->log2_max_mv_length_horizontal);192 rbsp_uev(rbsp, &vui->log21_max_mv_length_vertical);193 rbsp_uev(rbsp, &vui->max_num_reorder_frames);194 rbsp_uev(rbsp, &vui->max_dec_frame_buffering);195 }196}197 198static void nal_h264_rbsp_sps(struct rbsp *rbsp, struct nal_h264_sps *sps)199{200 unsigned int i;201 202 if (!sps) {203 rbsp->error = -EINVAL;204 return;205 }206 207 rbsp_bits(rbsp, 8, &sps->profile_idc);208 rbsp_bit(rbsp, &sps->constraint_set0_flag);209 rbsp_bit(rbsp, &sps->constraint_set1_flag);210 rbsp_bit(rbsp, &sps->constraint_set2_flag);211 rbsp_bit(rbsp, &sps->constraint_set3_flag);212 rbsp_bit(rbsp, &sps->constraint_set4_flag);213 rbsp_bit(rbsp, &sps->constraint_set5_flag);214 rbsp_bits(rbsp, 2, &sps->reserved_zero_2bits);215 rbsp_bits(rbsp, 8, &sps->level_idc);216 217 rbsp_uev(rbsp, &sps->seq_parameter_set_id);218 219 if (sps->profile_idc == 100 || sps->profile_idc == 110 ||220 sps->profile_idc == 122 || sps->profile_idc == 244 ||221 sps->profile_idc == 44 || sps->profile_idc == 83 ||222 sps->profile_idc == 86 || sps->profile_idc == 118 ||223 sps->profile_idc == 128 || sps->profile_idc == 138 ||224 sps->profile_idc == 139 || sps->profile_idc == 134 ||225 sps->profile_idc == 135) {226 rbsp_uev(rbsp, &sps->chroma_format_idc);227 228 if (sps->chroma_format_idc == 3)229 rbsp_bit(rbsp, &sps->separate_colour_plane_flag);230 rbsp_uev(rbsp, &sps->bit_depth_luma_minus8);231 rbsp_uev(rbsp, &sps->bit_depth_chroma_minus8);232 rbsp_bit(rbsp, &sps->qpprime_y_zero_transform_bypass_flag);233 rbsp_bit(rbsp, &sps->seq_scaling_matrix_present_flag);234 if (sps->seq_scaling_matrix_present_flag)235 rbsp->error = -EINVAL;236 }237 238 rbsp_uev(rbsp, &sps->log2_max_frame_num_minus4);239 240 rbsp_uev(rbsp, &sps->pic_order_cnt_type);241 switch (sps->pic_order_cnt_type) {242 case 0:243 rbsp_uev(rbsp, &sps->log2_max_pic_order_cnt_lsb_minus4);244 break;245 case 1:246 rbsp_bit(rbsp, &sps->delta_pic_order_always_zero_flag);247 rbsp_sev(rbsp, &sps->offset_for_non_ref_pic);248 rbsp_sev(rbsp, &sps->offset_for_top_to_bottom_field);249 250 rbsp_uev(rbsp, &sps->num_ref_frames_in_pic_order_cnt_cycle);251 for (i = 0; i < sps->num_ref_frames_in_pic_order_cnt_cycle; i++)252 rbsp_sev(rbsp, &sps->offset_for_ref_frame[i]);253 break;254 default:255 rbsp->error = -EINVAL;256 break;257 }258 259 rbsp_uev(rbsp, &sps->max_num_ref_frames);260 rbsp_bit(rbsp, &sps->gaps_in_frame_num_value_allowed_flag);261 rbsp_uev(rbsp, &sps->pic_width_in_mbs_minus1);262 rbsp_uev(rbsp, &sps->pic_height_in_map_units_minus1);263 264 rbsp_bit(rbsp, &sps->frame_mbs_only_flag);265 if (!sps->frame_mbs_only_flag)266 rbsp_bit(rbsp, &sps->mb_adaptive_frame_field_flag);267 268 rbsp_bit(rbsp, &sps->direct_8x8_inference_flag);269 270 rbsp_bit(rbsp, &sps->frame_cropping_flag);271 if (sps->frame_cropping_flag) {272 rbsp_uev(rbsp, &sps->crop_left);273 rbsp_uev(rbsp, &sps->crop_right);274 rbsp_uev(rbsp, &sps->crop_top);275 rbsp_uev(rbsp, &sps->crop_bottom);276 }277 278 rbsp_bit(rbsp, &sps->vui_parameters_present_flag);279 if (sps->vui_parameters_present_flag)280 nal_h264_rbsp_vui_parameters(rbsp, &sps->vui);281}282 283static void nal_h264_rbsp_pps(struct rbsp *rbsp, struct nal_h264_pps *pps)284{285 int i;286 287 rbsp_uev(rbsp, &pps->pic_parameter_set_id);288 rbsp_uev(rbsp, &pps->seq_parameter_set_id);289 rbsp_bit(rbsp, &pps->entropy_coding_mode_flag);290 rbsp_bit(rbsp, &pps->bottom_field_pic_order_in_frame_present_flag);291 rbsp_uev(rbsp, &pps->num_slice_groups_minus1);292 if (pps->num_slice_groups_minus1 > 0) {293 rbsp_uev(rbsp, &pps->slice_group_map_type);294 switch (pps->slice_group_map_type) {295 case 0:296 for (i = 0; i < pps->num_slice_groups_minus1; i++)297 rbsp_uev(rbsp, &pps->run_length_minus1[i]);298 break;299 case 2:300 for (i = 0; i < pps->num_slice_groups_minus1; i++) {301 rbsp_uev(rbsp, &pps->top_left[i]);302 rbsp_uev(rbsp, &pps->bottom_right[i]);303 }304 break;305 case 3: case 4: case 5:306 rbsp_bit(rbsp, &pps->slice_group_change_direction_flag);307 rbsp_uev(rbsp, &pps->slice_group_change_rate_minus1);308 break;309 case 6:310 rbsp_uev(rbsp, &pps->pic_size_in_map_units_minus1);311 for (i = 0; i < pps->pic_size_in_map_units_minus1; i++)312 rbsp_bits(rbsp,313 order_base_2(pps->num_slice_groups_minus1 + 1),314 &pps->slice_group_id[i]);315 break;316 default:317 break;318 }319 }320 rbsp_uev(rbsp, &pps->num_ref_idx_l0_default_active_minus1);321 rbsp_uev(rbsp, &pps->num_ref_idx_l1_default_active_minus1);322 rbsp_bit(rbsp, &pps->weighted_pred_flag);323 rbsp_bits(rbsp, 2, &pps->weighted_bipred_idc);324 rbsp_sev(rbsp, &pps->pic_init_qp_minus26);325 rbsp_sev(rbsp, &pps->pic_init_qs_minus26);326 rbsp_sev(rbsp, &pps->chroma_qp_index_offset);327 rbsp_bit(rbsp, &pps->deblocking_filter_control_present_flag);328 rbsp_bit(rbsp, &pps->constrained_intra_pred_flag);329 rbsp_bit(rbsp, &pps->redundant_pic_cnt_present_flag);330 if (/* more_rbsp_data() */ false) {331 rbsp_bit(rbsp, &pps->transform_8x8_mode_flag);332 rbsp_bit(rbsp, &pps->pic_scaling_matrix_present_flag);333 if (pps->pic_scaling_matrix_present_flag)334 rbsp->error = -EINVAL;335 rbsp_sev(rbsp, &pps->second_chroma_qp_index_offset);336 }337}338 339/**340 * nal_h264_write_sps() - Write SPS NAL unit into RBSP format341 * @dev: device pointer342 * @dest: the buffer that is filled with RBSP data343 * @n: maximum size of @dest in bytes344 * @sps: &struct nal_h264_sps to convert to RBSP345 *346 * Convert @sps to RBSP data and write it into @dest.347 *348 * The size of the SPS NAL unit is not known in advance and this function will349 * fail, if @dest does not hold sufficient space for the SPS NAL unit.350 *351 * Return: number of bytes written to @dest or negative error code352 */353ssize_t nal_h264_write_sps(const struct device *dev,354 void *dest, size_t n, struct nal_h264_sps *sps)355{356 struct rbsp rbsp;357 unsigned int forbidden_zero_bit = 0;358 unsigned int nal_ref_idc = 0;359 unsigned int nal_unit_type = SEQUENCE_PARAMETER_SET;360 361 if (!dest)362 return -EINVAL;363 364 rbsp_init(&rbsp, dest, n, &write);365 366 nal_h264_write_start_code_prefix(&rbsp);367 368 rbsp_bit(&rbsp, &forbidden_zero_bit);369 rbsp_bits(&rbsp, 2, &nal_ref_idc);370 rbsp_bits(&rbsp, 5, &nal_unit_type);371 372 nal_h264_rbsp_sps(&rbsp, sps);373 374 rbsp_trailing_bits(&rbsp);375 376 if (rbsp.error)377 return rbsp.error;378 379 return DIV_ROUND_UP(rbsp.pos, 8);380}381EXPORT_SYMBOL_GPL(nal_h264_write_sps);382 383/**384 * nal_h264_read_sps() - Read SPS NAL unit from RBSP format385 * @dev: device pointer386 * @sps: the &struct nal_h264_sps to fill from the RBSP data387 * @src: the buffer that contains the RBSP data388 * @n: size of @src in bytes389 *390 * Read RBSP data from @src and use it to fill @sps.391 *392 * Return: number of bytes read from @src or negative error code393 */394ssize_t nal_h264_read_sps(const struct device *dev,395 struct nal_h264_sps *sps, void *src, size_t n)396{397 struct rbsp rbsp;398 unsigned int forbidden_zero_bit;399 unsigned int nal_ref_idc;400 unsigned int nal_unit_type;401 402 if (!src)403 return -EINVAL;404 405 rbsp_init(&rbsp, src, n, &read);406 407 nal_h264_read_start_code_prefix(&rbsp);408 409 rbsp_bit(&rbsp, &forbidden_zero_bit);410 rbsp_bits(&rbsp, 2, &nal_ref_idc);411 rbsp_bits(&rbsp, 5, &nal_unit_type);412 413 if (rbsp.error ||414 forbidden_zero_bit != 0 ||415 nal_ref_idc != 0 ||416 nal_unit_type != SEQUENCE_PARAMETER_SET)417 return -EINVAL;418 419 nal_h264_rbsp_sps(&rbsp, sps);420 421 rbsp_trailing_bits(&rbsp);422 423 if (rbsp.error)424 return rbsp.error;425 426 return DIV_ROUND_UP(rbsp.pos, 8);427}428EXPORT_SYMBOL_GPL(nal_h264_read_sps);429 430/**431 * nal_h264_write_pps() - Write PPS NAL unit into RBSP format432 * @dev: device pointer433 * @dest: the buffer that is filled with RBSP data434 * @n: maximum size of @dest in bytes435 * @pps: &struct nal_h264_pps to convert to RBSP436 *437 * Convert @pps to RBSP data and write it into @dest.438 *439 * The size of the PPS NAL unit is not known in advance and this function will440 * fail, if @dest does not hold sufficient space for the PPS NAL unit.441 *442 * Return: number of bytes written to @dest or negative error code443 */444ssize_t nal_h264_write_pps(const struct device *dev,445 void *dest, size_t n, struct nal_h264_pps *pps)446{447 struct rbsp rbsp;448 unsigned int forbidden_zero_bit = 0;449 unsigned int nal_ref_idc = 0;450 unsigned int nal_unit_type = PICTURE_PARAMETER_SET;451 452 if (!dest)453 return -EINVAL;454 455 rbsp_init(&rbsp, dest, n, &write);456 457 nal_h264_write_start_code_prefix(&rbsp);458 459 /* NAL unit header */460 rbsp_bit(&rbsp, &forbidden_zero_bit);461 rbsp_bits(&rbsp, 2, &nal_ref_idc);462 rbsp_bits(&rbsp, 5, &nal_unit_type);463 464 nal_h264_rbsp_pps(&rbsp, pps);465 466 rbsp_trailing_bits(&rbsp);467 468 if (rbsp.error)469 return rbsp.error;470 471 return DIV_ROUND_UP(rbsp.pos, 8);472}473EXPORT_SYMBOL_GPL(nal_h264_write_pps);474 475/**476 * nal_h264_read_pps() - Read PPS NAL unit from RBSP format477 * @dev: device pointer478 * @pps: the &struct nal_h264_pps to fill from the RBSP data479 * @src: the buffer that contains the RBSP data480 * @n: size of @src in bytes481 *482 * Read RBSP data from @src and use it to fill @pps.483 *484 * Return: number of bytes read from @src or negative error code485 */486ssize_t nal_h264_read_pps(const struct device *dev,487 struct nal_h264_pps *pps, void *src, size_t n)488{489 struct rbsp rbsp;490 491 if (!src)492 return -EINVAL;493 494 rbsp_init(&rbsp, src, n, &read);495 496 nal_h264_read_start_code_prefix(&rbsp);497 498 /* NAL unit header */499 rbsp.pos += 8;500 501 nal_h264_rbsp_pps(&rbsp, pps);502 503 rbsp_trailing_bits(&rbsp);504 505 if (rbsp.error)506 return rbsp.error;507 508 return DIV_ROUND_UP(rbsp.pos, 8);509}510EXPORT_SYMBOL_GPL(nal_h264_read_pps);511 512/**513 * nal_h264_write_filler() - Write filler data RBSP514 * @dev: device pointer515 * @dest: buffer to fill with filler data516 * @n: size of the buffer to fill with filler data517 *518 * Write a filler data RBSP to @dest with a size of @n bytes and return the519 * number of written filler data bytes.520 *521 * Use this function to generate dummy data in an RBSP data stream that can be522 * safely ignored by h264 decoders.523 *524 * The RBSP format of the filler data is specified in Rec. ITU-T H.264525 * (04/2017) 7.3.2.7 Filler data RBSP syntax.526 *527 * Return: number of filler data bytes (including marker) or negative error528 */529ssize_t nal_h264_write_filler(const struct device *dev, void *dest, size_t n)530{531 struct rbsp rbsp;532 unsigned int forbidden_zero_bit = 0;533 unsigned int nal_ref_idc = 0;534 unsigned int nal_unit_type = FILLER_DATA;535 536 if (!dest)537 return -EINVAL;538 539 rbsp_init(&rbsp, dest, n, &write);540 541 nal_h264_write_start_code_prefix(&rbsp);542 543 rbsp_bit(&rbsp, &forbidden_zero_bit);544 rbsp_bits(&rbsp, 2, &nal_ref_idc);545 rbsp_bits(&rbsp, 5, &nal_unit_type);546 547 nal_h264_write_filler_data(&rbsp);548 549 rbsp_trailing_bits(&rbsp);550 551 return DIV_ROUND_UP(rbsp.pos, 8);552}553EXPORT_SYMBOL_GPL(nal_h264_write_filler);554 555/**556 * nal_h264_read_filler() - Read filler data RBSP557 * @dev: device pointer558 * @src: buffer with RBSP data that is read559 * @n: maximum size of src that shall be read560 *561 * Read a filler data RBSP from @src up to a maximum size of @n bytes and562 * return the size of the filler data in bytes including the marker.563 *564 * This function is used to parse filler data and skip the respective bytes in565 * the RBSP data.566 *567 * The RBSP format of the filler data is specified in Rec. ITU-T H.264568 * (04/2017) 7.3.2.7 Filler data RBSP syntax.569 *570 * Return: number of filler data bytes (including marker) or negative error571 */572ssize_t nal_h264_read_filler(const struct device *dev, void *src, size_t n)573{574 struct rbsp rbsp;575 unsigned int forbidden_zero_bit;576 unsigned int nal_ref_idc;577 unsigned int nal_unit_type;578 579 if (!src)580 return -EINVAL;581 582 rbsp_init(&rbsp, src, n, &read);583 584 nal_h264_read_start_code_prefix(&rbsp);585 586 rbsp_bit(&rbsp, &forbidden_zero_bit);587 rbsp_bits(&rbsp, 2, &nal_ref_idc);588 rbsp_bits(&rbsp, 5, &nal_unit_type);589 590 if (rbsp.error)591 return rbsp.error;592 if (forbidden_zero_bit != 0 ||593 nal_ref_idc != 0 ||594 nal_unit_type != FILLER_DATA)595 return -EINVAL;596 597 nal_h264_read_filler_data(&rbsp);598 rbsp_trailing_bits(&rbsp);599 600 if (rbsp.error)601 return rbsp.error;602 603 return DIV_ROUND_UP(rbsp.pos, 8);604}605EXPORT_SYMBOL_GPL(nal_h264_read_filler);606