/*
 * This file is part of FFmpeg.
 *
 * FFmpeg is free software; you can redistribute it and/or
 * modify it under the terms of the GNU Lesser General Public
 * License as published by the Free Software Foundation; either
 * version 2.1 of the License, or (at your option) any later version.
 *
 * FFmpeg is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
 * Lesser General Public License for more details.
 *
 * You should have received a copy of the GNU Lesser General Public
 * License along with FFmpeg; if not, write to the Free Software
 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
 */

#include <string.h>

#include <va/va.h>
#include <va/va_enc_hevc.h>

#include "libavutil/avassert.h"
#include "libavutil/common.h"
#include "libavutil/pixdesc.h"
#include "libavutil/opt.h"
#include "libavutil/mastering_display_metadata.h"

#include "atsc_a53.h"
#include "avcodec.h"
#include "cbs.h"
#include "cbs_h265.h"
#include "codec_internal.h"
#include "h2645data.h"
#include "h265_profile_level.h"
#include "hevc.h"
#include "hevc_sei.h"
#include "put_bits.h"
#include "vaapi_encode.h"

enum {
    SEI_MASTERING_DISPLAY       = 0x08,
    SEI_CONTENT_LIGHT_LEVEL     = 0x10,
    SEI_A53_CC                  = 0x20,
};

typedef struct VAAPIEncodeH265Picture {
    int pic_order_cnt;

    int64_t last_idr_frame;

    int slice_nal_unit;
    int slice_type;
    int pic_type;
} VAAPIEncodeH265Picture;

typedef struct VAAPIEncodeH265Context {
    VAAPIEncodeContext common;

    // Encoder features.
    uint32_t va_features;
    // Block size info.
    uint32_t va_bs;
    uint32_t ctu_size;
    uint32_t min_cb_size;

    // User options.
    int qp;
    int aud;
    int profile;
    int tier;
    int level;
    int sei;

    // Derived settings.
    int fixed_qp_idr;
    int fixed_qp_p;
    int fixed_qp_b;

    // Writer structures.
    H265RawAUD   raw_aud;
    H265RawVPS   raw_vps;
    H265RawSPS   raw_sps;
    H265RawPPS   raw_pps;
    H265RawSlice raw_slice;

    SEIRawMasteringDisplayColourVolume sei_mastering_display;
    SEIRawContentLightLevelInfo        sei_content_light_level;
    SEIRawUserDataRegistered           sei_a53cc;
    void                              *sei_a53cc_data;

    CodedBitstreamContext *cbc;
    CodedBitstreamFragment current_access_unit;
    int aud_needed;
    int sei_needed;
} VAAPIEncodeH265Context;


static int vaapi_encode_h265_write_access_unit(AVCodecContext *avctx,
                                               char *data, size_t *data_len,
                                               CodedBitstreamFragment *au)
{
    VAAPIEncodeH265Context *priv = avctx->priv_data;
    int err;

    err = ff_cbs_write_fragment_data(priv->cbc, au);
    if (err < 0) {
        av_log(avctx, AV_LOG_ERROR, "Failed to write packed header.\n");
        return err;
    }

    if (*data_len < 8 * au->data_size - au->data_bit_padding) {
        av_log(avctx, AV_LOG_ERROR, "Access unit too large: "
               "%zu < %zu.\n", *data_len,
               8 * au->data_size - au->data_bit_padding);
        return AVERROR(ENOSPC);
    }

    memcpy(data, au->data, au->data_size);
    *data_len = 8 * au->data_size - au->data_bit_padding;

    return 0;
}

static int vaapi_encode_h265_add_nal(AVCodecContext *avctx,
                                     CodedBitstreamFragment *au,
                                     void *nal_unit)
{
    H265RawNALUnitHeader *header = nal_unit;
    int err;

    err = ff_cbs_insert_unit_content(au, -1,
                                     header->nal_unit_type, nal_unit, NULL);
    if (err < 0) {
        av_log(avctx, AV_LOG_ERROR, "Failed to add NAL unit: "
               "type = %d.\n", header->nal_unit_type);
        return err;
    }

    return 0;
}

static int vaapi_encode_h265_write_sequence_header(AVCodecContext *avctx,
                                                   char *data, size_t *data_len)
{
    VAAPIEncodeH265Context *priv = avctx->priv_data;
    CodedBitstreamFragment   *au = &priv->current_access_unit;
    int err;

    if (priv->aud_needed) {
        err = vaapi_encode_h265_add_nal(avctx, au, &priv->raw_aud);
        if (err < 0)
            goto fail;
        priv->aud_needed = 0;
    }

    err = vaapi_encode_h265_add_nal(avctx, au, &priv->raw_vps);
    if (err < 0)
        goto fail;

    err = vaapi_encode_h265_add_nal(avctx, au, &priv->raw_sps);
    if (err < 0)
        goto fail;

    err = vaapi_encode_h265_add_nal(avctx, au, &priv->raw_pps);
    if (err < 0)
        goto fail;

    err = vaapi_encode_h265_write_access_unit(avctx, data, data_len, au);
fail:
    ff_cbs_fragment_reset(au);
    return err;
}

static int vaapi_encode_h265_write_slice_header(AVCodecContext *avctx,
                                                VAAPIEncodePicture *pic,
                                                VAAPIEncodeSlice *slice,
                                                char *data, size_t *data_len)
{
    VAAPIEncodeH265Context *priv = avctx->priv_data;
    CodedBitstreamFragment   *au = &priv->current_access_unit;
    int err;

    if (priv->aud_needed) {
        err = vaapi_encode_h265_add_nal(avctx, au, &priv->raw_aud);
        if (err < 0)
            goto fail;
        priv->aud_needed = 0;
    }

    err = vaapi_encode_h265_add_nal(avctx, au, &priv->raw_slice);
    if (err < 0)
        goto fail;

    err = vaapi_encode_h265_write_access_unit(avctx, data, data_len, au);
fail:
    ff_cbs_fragment_reset(au);
    return err;
}

static int vaapi_encode_h265_write_extra_header(AVCodecContext *avctx,
                                                VAAPIEncodePicture *pic,
                                                int index, int *type,
                                                char *data, size_t *data_len)
{
    VAAPIEncodeH265Context *priv = avctx->priv_data;
    CodedBitstreamFragment   *au = &priv->current_access_unit;
    int err;

    if (priv->sei_needed) {
        if (priv->aud_needed) {
            err = vaapi_encode_h265_add_nal(avctx, au, &priv->aud);
            if (err < 0)
                goto fail;
            priv->aud_needed = 0;
        }

        if (priv->sei_needed & SEI_MASTERING_DISPLAY) {
            err = ff_cbs_sei_add_message(priv->cbc, au, 1,
                                         SEI_TYPE_MASTERING_DISPLAY_COLOUR_VOLUME,
                                         &priv->sei_mastering_display, NULL);
            if (err < 0)
                goto fail;
        }

        if (priv->sei_needed & SEI_CONTENT_LIGHT_LEVEL) {
            err = ff_cbs_sei_add_message(priv->cbc, au, 1,
                                         SEI_TYPE_CONTENT_LIGHT_LEVEL_INFO,
                                         &priv->sei_content_light_level, NULL);
            if (err < 0)
                goto fail;
        }
        if (priv->sei_needed & SEI_A53_CC) {
            err = ff_cbs_sei_add_message(priv->cbc, au, 1,
                                         SEI_TYPE_USER_DATA_REGISTERED_ITU_T_T35,
                                         &priv->sei_a53cc, NULL);
            if (err < 0)
                goto fail;
        }

        priv->sei_needed = 0;

        err = vaapi_encode_h265_write_access_unit(avctx, data, data_len, au);
        if (err < 0)
            goto fail;

        ff_cbs_fragment_reset(au);

        *type = VAEncPackedHeaderRawData;
        return 0;
    } else {
        return AVERROR_EOF;
    }

fail:
    ff_cbs_fragment_reset(au);
    return err;
}

static int vaapi_encode_h265_init_sequence_params(AVCodecContext *avctx)
{
    VAAPIEncodeContext                *ctx = avctx->priv_data;
    VAAPIEncodeH265Context           *priv = avctx->priv_data;
    H265RawVPS                        *vps = &priv->raw_vps;
    H265RawSPS                        *sps = &priv->raw_sps;
    H265RawPPS                        *pps = &priv->raw_pps;
    H265RawProfileTierLevel           *ptl = &vps->profile_tier_level;
    H265RawVUI                        *vui = &sps->vui;
    VAEncSequenceParameterBufferHEVC *vseq = ctx->codec_sequence_params;
    VAEncPictureParameterBufferHEVC  *vpic = ctx->codec_picture_params;
    const AVPixFmtDescriptor *desc;
    int chroma_format, bit_depth;
    int i;

    memset(vps, 0, sizeof(*vps));
    memset(sps, 0, sizeof(*sps));
    memset(pps, 0, sizeof(*pps));


    desc = av_pix_fmt_desc_get(priv->common.input_frames->sw_format);
    av_assert0(desc);
    if (desc->nb_components == 1) {
        chroma_format = 0;
    } else {
        if (desc->log2_chroma_w == 1 && desc->log2_chroma_h == 1) {
            chroma_format = 1;
        } else if (desc->log2_chroma_w == 1 && desc->log2_chroma_h == 0) {
            chroma_format = 2;
        } else if (desc->log2_chroma_w == 0 && desc->log2_chroma_h == 0) {
            chroma_format = 3;
        } else {
            av_log(avctx, AV_LOG_ERROR, "Chroma format of input pixel format "
                   "%s is not supported.\n", desc->name);
            return AVERROR(EINVAL);
        }
    }
    bit_depth = desc->comp[0].depth;


    // VPS

    vps->nal_unit_header = (H265RawNALUnitHeader) {
        .nal_unit_type         = HEVC_NAL_VPS,
        .nuh_layer_id          = 0,
        .nuh_temporal_id_plus1 = 1,
    };

    vps->vps_video_parameter_set_id = 0;

    vps->vps_base_layer_internal_flag  = 1;
    vps->vps_base_layer_available_flag = 1;
    vps->vps_max_layers_minus1         = 0;
    vps->vps_max_sub_layers_minus1     = 0;
    vps->vps_temporal_id_nesting_flag  = 1;

    ptl->general_profile_space = 0;
    ptl->general_profile_idc   = avctx->profile;
    ptl->general_tier_flag     = priv->tier;

    ptl->general_profile_compatibility_flag[ptl->general_profile_idc] = 1;

    if (ptl->general_profile_compatibility_flag[1])
        ptl->general_profile_compatibility_flag[2] = 1;
    if (ptl->general_profile_compatibility_flag[3]) {
        ptl->general_profile_compatibility_flag[1] = 1;
        ptl->general_profile_compatibility_flag[2] = 1;
    }

    ptl->general_progressive_source_flag    = 1;
    ptl->general_interlaced_source_flag     = 0;
    ptl->general_non_packed_constraint_flag = 1;
    ptl->general_frame_only_constraint_flag = 1;

    ptl->general_max_14bit_constraint_flag = bit_depth <= 14;
    ptl->general_max_12bit_constraint_flag = bit_depth <= 12;
    ptl->general_max_10bit_constraint_flag = bit_depth <= 10;
    ptl->general_max_8bit_constraint_flag  = bit_depth ==  8;

    ptl->general_max_422chroma_constraint_flag  = chroma_format <= 2;
    ptl->general_max_420chroma_constraint_flag  = chroma_format <= 1;
    ptl->general_max_monochrome_constraint_flag = chroma_format == 0;

    ptl->general_intra_constraint_flag = ctx->gop_size == 1;
    ptl->general_one_picture_only_constraint_flag = 0;

    ptl->general_lower_bit_rate_constraint_flag = 1;

    if (avctx->level != AV_LEVEL_UNKNOWN) {
        ptl->general_level_idc = avctx->level;
    } else {
        const H265LevelDescriptor *level;

        level = ff_h265_guess_level(ptl, avctx->bit_rate,
                                    ctx->surface_width, ctx->surface_height,
                                    ctx->nb_slices, ctx->tile_rows, ctx->tile_cols,
                                    (ctx->b_per_p > 0) + 1);
        if (level) {
            av_log(avctx, AV_LOG_VERBOSE, "Using level %s.\n", level->name);
            ptl->general_level_idc = level->level_idc;
        } else {
            av_log(avctx, AV_LOG_VERBOSE, "Stream will not conform to "
                   "any normal level; using level 8.5.\n");
            ptl->general_level_idc = 255;
            // The tier flag must be set in level 8.5.
            ptl->general_tier_flag = 1;
        }
    }

    vps->vps_sub_layer_ordering_info_present_flag = 0;
    vps->vps_max_dec_pic_buffering_minus1[0]      = ctx->max_b_depth + 1;
    vps->vps_max_num_reorder_pics[0]              = ctx->max_b_depth;
    vps->vps_max_latency_increase_plus1[0]        = 0;

    vps->vps_max_layer_id             = 0;
    vps->vps_num_layer_sets_minus1    = 0;
    vps->layer_id_included_flag[0][0] = 1;

    vps->vps_timing_info_present_flag = 1;
    if (avctx->framerate.num > 0 && avctx->framerate.den > 0) {
        vps->vps_num_units_in_tick  = avctx->framerate.den;
        vps->vps_time_scale         = avctx->framerate.num;
        vps->vps_poc_proportional_to_timing_flag = 1;
        vps->vps_num_ticks_poc_diff_one_minus1   = 0;
    } else {
        vps->vps_num_units_in_tick  = avctx->time_base.num;
        vps->vps_time_scale         = avctx->time_base.den;
        vps->vps_poc_proportional_to_timing_flag = 0;
    }
    vps->vps_num_hrd_parameters = 0;


    // SPS

    sps->nal_unit_header = (H265RawNALUnitHeader) {
        .nal_unit_type         = HEVC_NAL_SPS,
        .nuh_layer_id          = 0,
        .nuh_temporal_id_plus1 = 1,
    };

    sps->sps_video_parameter_set_id = vps->vps_video_parameter_set_id;

    sps->sps_max_sub_layers_minus1    = vps->vps_max_sub_layers_minus1;
    sps->sps_temporal_id_nesting_flag = vps->vps_temporal_id_nesting_flag;

    sps->profile_tier_level = vps->profile_tier_level;

    sps->sps_seq_parameter_set_id = 0;

    sps->chroma_format_idc          = chroma_format;
    sps->separate_colour_plane_flag = 0;

    sps->pic_width_in_luma_samples  = ctx->surface_width;
    sps->pic_height_in_luma_samples = ctx->surface_height;

    if (avctx->width  != ctx->surface_width ||
        avctx->height != ctx->surface_height) {
        sps->conformance_window_flag = 1;
        sps->conf_win_left_offset   = 0;
        sps->conf_win_right_offset  =
            (ctx->surface_width - avctx->width) >> desc->log2_chroma_w;
        sps->conf_win_top_offset    = 0;
        sps->conf_win_bottom_offset =
            (ctx->surface_height - avctx->height) >> desc->log2_chroma_h;
    } else {
        sps->conformance_window_flag = 0;
    }

    sps->bit_depth_luma_minus8   = bit_depth - 8;
    sps->bit_depth_chroma_minus8 = bit_depth - 8;

    sps->log2_max_pic_order_cnt_lsb_minus4 = 8;

    sps->sps_sub_layer_ordering_info_present_flag =
        vps->vps_sub_layer_ordering_info_present_flag;
    for (i = 0; i <= sps->sps_max_sub_layers_minus1; i++) {
        sps->sps_max_dec_pic_buffering_minus1[i] =
            vps->vps_max_dec_pic_buffering_minus1[i];
        sps->sps_max_num_reorder_pics[i] =
            vps->vps_max_num_reorder_pics[i];
        sps->sps_max_latency_increase_plus1[i] =
            vps->vps_max_latency_increase_plus1[i];
    }

    // These values come from the capabilities of the first encoder
    // implementation in the i965 driver on Intel Skylake.  They may
    // fail badly with other platforms or drivers.
    // CTB size from 8x8 to 32x32.
    sps->log2_min_luma_coding_block_size_minus3   = 0;
    sps->log2_diff_max_min_luma_coding_block_size = 2;
    // Transform size from 4x4 to 32x32.
    sps->log2_min_luma_transform_block_size_minus2   = 0;
    sps->log2_diff_max_min_luma_transform_block_size = 3;
    // Full transform hierarchy allowed (2-5).
    sps->max_transform_hierarchy_depth_inter = 3;
    sps->max_transform_hierarchy_depth_intra = 3;
    // AMP works.
    sps->amp_enabled_flag = 1;
    // SAO and temporal MVP do not work.
    sps->sample_adaptive_offset_enabled_flag = 0;
    sps->sps_temporal_mvp_enabled_flag       = 0;

    sps->pcm_enabled_flag = 0;

// update sps setting according to queried result
#if VA_CHECK_VERSION(1, 13, 0)
    if (priv->va_features) {
        VAConfigAttribValEncHEVCFeatures features = { .value = priv->va_features };

        // Enable feature if get queried result is VA_FEATURE_SUPPORTED | VA_FEATURE_REQUIRED
        sps->amp_enabled_flag =
            !!features.bits.amp;
        sps->sample_adaptive_offset_enabled_flag =
            !!features.bits.sao;
        sps->sps_temporal_mvp_enabled_flag =
            !!features.bits.temporal_mvp;
        sps->pcm_enabled_flag =
            !!features.bits.pcm;
    }

    if (priv->va_bs) {
        VAConfigAttribValEncHEVCBlockSizes bs = { .value = priv->va_bs };
        sps->log2_min_luma_coding_block_size_minus3 =
            ff_ctz(priv->min_cb_size) - 3;
        sps->log2_diff_max_min_luma_coding_block_size =
            ff_ctz(priv->ctu_size) - ff_ctz(priv->min_cb_size);

        sps->log2_min_luma_transform_block_size_minus2 =
            bs.bits.log2_min_luma_transform_block_size_minus2;
        sps->log2_diff_max_min_luma_transform_block_size =
            bs.bits.log2_max_luma_transform_block_size_minus2 -
            bs.bits.log2_min_luma_transform_block_size_minus2;

        sps->max_transform_hierarchy_depth_inter =
            bs.bits.max_max_transform_hierarchy_depth_inter;
        sps->max_transform_hierarchy_depth_intra =
            bs.bits.max_max_transform_hierarchy_depth_intra;
    }
#endif

    // STRPSs should ideally be here rather than defined individually in
    // each slice, but the structure isn't completely fixed so for now
    // don't bother.
    sps->num_short_term_ref_pic_sets     = 0;
    sps->long_term_ref_pics_present_flag = 0;

    sps->vui_parameters_present_flag = 1;

    if (avctx->sample_aspect_ratio.num != 0 &&
        avctx->sample_aspect_ratio.den != 0) {
        int num, den, i;
        av_reduce(&num, &den, avctx->sample_aspect_ratio.num,
                  avctx->sample_aspect_ratio.den, 65535);
        for (i = 0; i < FF_ARRAY_ELEMS(ff_h2645_pixel_aspect); i++) {
            if (num == ff_h2645_pixel_aspect[i].num &&
                den == ff_h2645_pixel_aspect[i].den) {
                vui->aspect_ratio_idc = i;
                break;
            }
        }
        if (i >= FF_ARRAY_ELEMS(ff_h2645_pixel_aspect)) {
            vui->aspect_ratio_idc = 255;
            vui->sar_width  = num;
            vui->sar_height = den;
        }
        vui->aspect_ratio_info_present_flag = 1;
    }

    // Unspecified video format, from table E-2.
    vui->video_format             = 5;
    vui->video_full_range_flag    =
        avctx->color_range == AVCOL_RANGE_JPEG;
    vui->colour_primaries         = avctx->color_primaries;
    vui->transfer_characteristics = avctx->color_trc;
    vui->matrix_coefficients      = avctx->colorspace;
    if (avctx->color_primaries != AVCOL_PRI_UNSPECIFIED ||
        avctx->color_trc       != AVCOL_TRC_UNSPECIFIED ||
        avctx->colorspace      != AVCOL_SPC_UNSPECIFIED)
        vui->colour_description_present_flag = 1;
    if (avctx->color_range     != AVCOL_RANGE_UNSPECIFIED ||
        vui->colour_description_present_flag)
        vui->video_signal_type_present_flag = 1;

    if (avctx->chroma_sample_location != AVCHROMA_LOC_UNSPECIFIED) {
        vui->chroma_loc_info_present_flag = 1;
        vui->chroma_sample_loc_type_top_field    =
        vui->chroma_sample_loc_type_bottom_field =
            avctx->chroma_sample_location - 1;
    }

    vui->vui_timing_info_present_flag        = 1;
    vui->vui_num_units_in_tick               = vps->vps_num_units_in_tick;
    vui->vui_time_scale                      = vps->vps_time_scale;
    vui->vui_poc_proportional_to_timing_flag = vps->vps_poc_proportional_to_timing_flag;
    vui->vui_num_ticks_poc_diff_one_minus1   = vps->vps_num_ticks_poc_diff_one_minus1;
    vui->vui_hrd_parameters_present_flag     = 0;

    vui->bitstream_restriction_flag    = 1;
    vui->motion_vectors_over_pic_boundaries_flag = 1;
    vui->restricted_ref_pic_lists_flag = 1;
    vui->max_bytes_per_pic_denom       = 0;
    vui->max_bits_per_min_cu_denom     = 0;
    vui->log2_max_mv_length_horizontal = 15;
    vui->log2_max_mv_length_vertical   = 15;


    // PPS

    pps->nal_unit_header = (H265RawNALUnitHeader) {
        .nal_unit_type         = HEVC_NAL_PPS,
        .nuh_layer_id          = 0,
        .nuh_temporal_id_plus1 = 1,
    };

    pps->pps_pic_parameter_set_id = 0;
    pps->pps_seq_parameter_set_id = sps->sps_seq_parameter_set_id;

    pps->num_ref_idx_l0_default_active_minus1 = 0;
    pps->num_ref_idx_l1_default_active_minus1 = 0;

    pps->init_qp_minus26 = priv->fixed_qp_idr - 26;

    pps->cu_qp_delta_enabled_flag = (ctx->va_rc_mode != VA_RC_CQP);
    pps->diff_cu_qp_delta_depth   = 0;

// update pps setting according to queried result
#if VA_CHECK_VERSION(1, 13, 0)
    if (priv->va_features) {
        VAConfigAttribValEncHEVCFeatures features = { .value = priv->va_features };
        if (ctx->va_rc_mode != VA_RC_CQP)
            pps->cu_qp_delta_enabled_flag =
                !!features.bits.cu_qp_delta;

        pps->transform_skip_enabled_flag =
            !!features.bits.transform_skip;
        // set diff_cu_qp_delta_depth as its max value if cu_qp_delta enabled. Otherwise
        // 0 will make cu_qp_delta invalid.
        if (pps->cu_qp_delta_enabled_flag)
            pps->diff_cu_qp_delta_depth = sps->log2_diff_max_min_luma_coding_block_size;
    }
#endif

    if (ctx->tile_rows && ctx->tile_cols) {
        int uniform_spacing;

        pps->tiles_enabled_flag      = 1;
        pps->num_tile_columns_minus1 = ctx->tile_cols - 1;
        pps->num_tile_rows_minus1    = ctx->tile_rows - 1;

        // Test whether the spacing provided matches the H.265 uniform
        // spacing, and set the flag if it does.
        uniform_spacing = 1;
        for (i = 0; i <= pps->num_tile_columns_minus1 &&
                    uniform_spacing; i++) {
            if (ctx->col_width[i] !=
                (i + 1) * ctx->slice_block_cols / ctx->tile_cols -
                 i      * ctx->slice_block_cols / ctx->tile_cols)
                uniform_spacing = 0;
        }
        for (i = 0; i <= pps->num_tile_rows_minus1 &&
                    uniform_spacing; i++) {
            if (ctx->row_height[i] !=
                (i + 1) * ctx->slice_block_rows / ctx->tile_rows -
                 i      * ctx->slice_block_rows / ctx->tile_rows)
                uniform_spacing = 0;
        }
        pps->uniform_spacing_flag = uniform_spacing;

        for (i = 0; i <= pps->num_tile_columns_minus1; i++)
            pps->column_width_minus1[i] = ctx->col_width[i] - 1;
        for (i = 0; i <= pps->num_tile_rows_minus1; i++)
            pps->row_height_minus1[i]   = ctx->row_height[i] - 1;

        pps->loop_filter_across_tiles_enabled_flag = 1;
    }

    pps->pps_loop_filter_across_slices_enabled_flag = 1;

    // Fill VAAPI parameter buffers.

    *vseq = (VAEncSequenceParameterBufferHEVC) {
        .general_profile_idc = vps->profile_tier_level.general_profile_idc,
        .general_level_idc   = vps->profile_tier_level.general_level_idc,
        .general_tier_flag   = vps->profile_tier_level.general_tier_flag,

        .intra_period     = ctx->gop_size,
        .intra_idr_period = ctx->gop_size,
        .ip_period        = ctx->b_per_p + 1,
        .bits_per_second  = ctx->va_bit_rate,

        .pic_width_in_luma_samples  = sps->pic_width_in_luma_samples,
        .pic_height_in_luma_samples = sps->pic_height_in_luma_samples,

        .seq_fields.bits = {
            .chroma_format_idc             = sps->chroma_format_idc,
            .separate_colour_plane_flag    = sps->separate_colour_plane_flag,
            .bit_depth_luma_minus8         = sps->bit_depth_luma_minus8,
            .bit_depth_chroma_minus8       = sps->bit_depth_chroma_minus8,
            .scaling_list_enabled_flag     = sps->scaling_list_enabled_flag,
            .strong_intra_smoothing_enabled_flag =
                sps->strong_intra_smoothing_enabled_flag,
            .amp_enabled_flag              = sps->amp_enabled_flag,
            .sample_adaptive_offset_enabled_flag =
                sps->sample_adaptive_offset_enabled_flag,
            .pcm_enabled_flag              = sps->pcm_enabled_flag,
            .pcm_loop_filter_disabled_flag = sps->pcm_loop_filter_disabled_flag,
            .sps_temporal_mvp_enabled_flag = sps->sps_temporal_mvp_enabled_flag,
        },

        .log2_min_luma_coding_block_size_minus3 =
            sps->log2_min_luma_coding_block_size_minus3,
        .log2_diff_max_min_luma_coding_block_size =
            sps->log2_diff_max_min_luma_coding_block_size,
        .log2_min_transform_block_size_minus2 =
            sps->log2_min_luma_transform_block_size_minus2,
        .log2_diff_max_min_transform_block_size =
            sps->log2_diff_max_min_luma_transform_block_size,
        .max_transform_hierarchy_depth_inter =
            sps->max_transform_hierarchy_depth_inter,
        .max_transform_hierarchy_depth_intra =
            sps->max_transform_hierarchy_depth_intra,

        .pcm_sample_bit_depth_luma_minus1 =
            sps->pcm_sample_bit_depth_luma_minus1,
        .pcm_sample_bit_depth_chroma_minus1 =
            sps->pcm_sample_bit_depth_chroma_minus1,
        .log2_min_pcm_luma_coding_block_size_minus3 =
            sps->log2_min_pcm_luma_coding_block_size_minus3,
        .log2_max_pcm_luma_coding_block_size_minus3 =
            sps->log2_min_pcm_luma_coding_block_size_minus3 +
            sps->log2_diff_max_min_pcm_luma_coding_block_size,

        .vui_parameters_present_flag = 0,
    };

    *vpic = (VAEncPictureParameterBufferHEVC) {
        .decoded_curr_pic = {
            .picture_id = VA_INVALID_ID,
            .flags      = VA_PICTURE_HEVC_INVALID,
        },

        .coded_buf = VA_INVALID_ID,

        .collocated_ref_pic_index = sps->sps_temporal_mvp_enabled_flag ?
                                    0 : 0xff,
        .last_picture = 0,

        .pic_init_qp            = pps->init_qp_minus26 + 26,
        .diff_cu_qp_delta_depth = pps->diff_cu_qp_delta_depth,
        .pps_cb_qp_offset       = pps->pps_cb_qp_offset,
        .pps_cr_qp_offset       = pps->pps_cr_qp_offset,

        .num_tile_columns_minus1 = pps->num_tile_columns_minus1,
        .num_tile_rows_minus1    = pps->num_tile_rows_minus1,

        .log2_parallel_merge_level_minus2 = pps->log2_parallel_merge_level_minus2,
        .ctu_max_bitsize_allowed          = 0,

        .num_ref_idx_l0_default_active_minus1 =
            pps->num_ref_idx_l0_default_active_minus1,
        .num_ref_idx_l1_default_active_minus1 =
            pps->num_ref_idx_l1_default_active_minus1,

        .slice_pic_parameter_set_id = pps->pps_pic_parameter_set_id,

        .pic_fields.bits = {
            .sign_data_hiding_enabled_flag  = pps->sign_data_hiding_enabled_flag,
            .constrained_intra_pred_flag    = pps->constrained_intra_pred_flag,
            .transform_skip_enabled_flag    = pps->transform_skip_enabled_flag,
            .cu_qp_delta_enabled_flag       = pps->cu_qp_delta_enabled_flag,
            .weighted_pred_flag             = pps->weighted_pred_flag,
            .weighted_bipred_flag           = pps->weighted_bipred_flag,
            .transquant_bypass_enabled_flag = pps->transquant_bypass_enabled_flag,
            .tiles_enabled_flag             = pps->tiles_enabled_flag,
            .entropy_coding_sync_enabled_flag = pps->entropy_coding_sync_enabled_flag,
            .loop_filter_across_tiles_enabled_flag =
                pps->loop_filter_across_tiles_enabled_flag,
            .pps_loop_filter_across_slices_enabled_flag =
                pps->pps_loop_filter_across_slices_enabled_flag,
            .scaling_list_data_present_flag = (sps->sps_scaling_list_data_present_flag |
                                               pps->pps_scaling_list_data_present_flag),
            .screen_content_flag            = 0,
            .enable_gpu_weighted_prediction = 0,
            .no_output_of_prior_pics_flag   = 0,
        },
    };

    if (pps->tiles_enabled_flag) {
        for (i = 0; i <= vpic->num_tile_rows_minus1; i++)
            vpic->row_height_minus1[i]   = pps->row_height_minus1[i];
        for (i = 0; i <= vpic->num_tile_columns_minus1; i++)
            vpic->column_width_minus1[i] = pps->column_width_minus1[i];
    }

    return 0;
}

static int vaapi_encode_h265_init_picture_params(AVCodecContext *avctx,
                                                 VAAPIEncodePicture *pic)
{
    VAAPIEncodeContext               *ctx = avctx->priv_data;
    VAAPIEncodeH265Context          *priv = avctx->priv_data;
    VAAPIEncodeH265Picture          *hpic = pic->priv_data;
    VAAPIEncodePicture              *prev = pic->prev;
    VAAPIEncodeH265Picture         *hprev = prev ? prev->priv_data : NULL;
    VAEncPictureParameterBufferHEVC *vpic = pic->codec_picture_params;
    int i, j = 0;

    if (pic->type == PICTURE_TYPE_IDR) {
        av_assert0(pic->display_order == pic->encode_order);

        hpic->last_idr_frame = pic->display_order;

        hpic->slice_nal_unit = HEVC_NAL_IDR_W_RADL;
        hpic->slice_type     = HEVC_SLICE_I;
        hpic->pic_type       = 0;
    } else {
        av_assert0(prev);
        hpic->last_idr_frame = hprev->last_idr_frame;

        if (pic->type == PICTURE_TYPE_I) {
            hpic->slice_nal_unit = HEVC_NAL_CRA_NUT;
            hpic->slice_type     = HEVC_SLICE_I;
            hpic->pic_type       = 0;
        } else if (pic->type == PICTURE_TYPE_P) {
            av_assert0(pic->refs[0]);
            hpic->slice_nal_unit = HEVC_NAL_TRAIL_R;
            hpic->slice_type     = HEVC_SLICE_P;
            hpic->pic_type       = 1;
        } else {
            VAAPIEncodePicture *irap_ref;
            av_assert0(pic->refs[0][0] && pic->refs[1][0]);
            for (irap_ref = pic; irap_ref; irap_ref = irap_ref->refs[1][0]) {
                if (irap_ref->type == PICTURE_TYPE_I)
                    break;
            }
            if (pic->b_depth == ctx->max_b_depth) {
                hpic->slice_nal_unit = irap_ref ? HEVC_NAL_RASL_N
                                                : HEVC_NAL_TRAIL_N;
            } else {
                hpic->slice_nal_unit = irap_ref ? HEVC_NAL_RASL_R
                                                : HEVC_NAL_TRAIL_R;
            }
            hpic->slice_type = HEVC_SLICE_B;
            hpic->pic_type   = 2;
        }
    }
    hpic->pic_order_cnt = pic->display_order - hpic->last_idr_frame;

    if (priv->aud) {
        priv->aud_needed = 1;
        priv->raw_aud = (H265RawAUD) {
            .nal_unit_header = {
                .nal_unit_type         = HEVC_NAL_AUD,
                .nuh_layer_id          = 0,
                .nuh_temporal_id_plus1 = 1,
            },
            .pic_type = hpic->pic_type,
        };
    } else {
        priv->aud_needed = 0;
    }

    priv->sei_needed = 0;

    // Only look for the metadata on I/IDR frame on the output. We
    // may force an IDR frame on the output where the medadata gets
    // changed on the input frame.
    if ((priv->sei & SEI_MASTERING_DISPLAY) &&
        (pic->type == PICTURE_TYPE_I || pic->type == PICTURE_TYPE_IDR)) {
        AVFrameSideData *sd =
            av_frame_get_side_data(pic->input_image,
                                   AV_FRAME_DATA_MASTERING_DISPLAY_METADATA);

        if (sd) {
            AVMasteringDisplayMetadata *mdm =
                (AVMasteringDisplayMetadata *)sd->data;

            // SEI is needed when both the primaries and luminance are set
            if (mdm->has_primaries && mdm->has_luminance) {
                SEIRawMasteringDisplayColourVolume *mdcv =
                    &priv->sei_mastering_display;
                const int mapping[3] = {1, 2, 0};
                const int chroma_den = 50000;
                const int luma_den   = 10000;

                for (i = 0; i < 3; i++) {
                    const int j = mapping[i];
                    mdcv->display_primaries_x[i] =
                        FFMIN(lrint(chroma_den *
                                    av_q2d(mdm->display_primaries[j][0])),
                              chroma_den);
                    mdcv->display_primaries_y[i] =
                        FFMIN(lrint(chroma_den *
                                    av_q2d(mdm->display_primaries[j][1])),
                              chroma_den);
                }

                mdcv->white_point_x =
                    FFMIN(lrint(chroma_den * av_q2d(mdm->white_point[0])),
                          chroma_den);
                mdcv->white_point_y =
                    FFMIN(lrint(chroma_den * av_q2d(mdm->white_point[1])),
                          chroma_den);

                mdcv->max_display_mastering_luminance =
                    lrint(luma_den * av_q2d(mdm->max_luminance));
                mdcv->min_display_mastering_luminance =
                    FFMIN(lrint(luma_den * av_q2d(mdm->min_luminance)),
                          mdcv->max_display_mastering_luminance);

                priv->sei_needed |= SEI_MASTERING_DISPLAY;
            }
        }
    }

    if ((priv->sei & SEI_CONTENT_LIGHT_LEVEL) &&
        (pic->type == PICTURE_TYPE_I || pic->type == PICTURE_TYPE_IDR)) {
        AVFrameSideData *sd =
            av_frame_get_side_data(pic->input_image,
                                   AV_FRAME_DATA_CONTENT_LIGHT_LEVEL);

        if (sd) {
            AVContentLightMetadata *clm =
                (AVContentLightMetadata *)sd->data;
            SEIRawContentLightLevelInfo *clli =
                &priv->sei_content_light_level;

            clli->max_content_light_level     = FFMIN(clm->MaxCLL,  65535);
            clli->max_pic_average_light_level = FFMIN(clm->MaxFALL, 65535);

            priv->sei_needed |= SEI_CONTENT_LIGHT_LEVEL;
        }
    }

    if (priv->sei & SEI_A53_CC) {
        int err;
        size_t sei_a53cc_len;
        av_freep(&priv->sei_a53cc_data);
        err = ff_alloc_a53_sei(pic->input_image, 0, &priv->sei_a53cc_data, &sei_a53cc_len);
        if (err < 0)
            return err;
        if (priv->sei_a53cc_data != NULL) {
            priv->sei_a53cc.itu_t_t35_country_code = 181;
            priv->sei_a53cc.data = (uint8_t *)priv->sei_a53cc_data + 1;
            priv->sei_a53cc.data_length = sei_a53cc_len - 1;

            priv->sei_needed |= SEI_A53_CC;
        }
    }

    vpic->decoded_curr_pic = (VAPictureHEVC) {
        .picture_id    = pic->recon_surface,
        .pic_order_cnt = hpic->pic_order_cnt,
        .flags         = 0,
    };

    for (int k = 0; k < MAX_REFERENCE_LIST_NUM; k++) {
        for (i = 0; i < pic->nb_refs[k]; i++) {
            VAAPIEncodePicture      *ref = pic->refs[k][i];
            VAAPIEncodeH265Picture *href;

            av_assert0(ref && ref->encode_order < pic->encode_order);
            href = ref->priv_data;

            vpic->reference_frames[j++] = (VAPictureHEVC) {
                .picture_id    = ref->recon_surface,
                .pic_order_cnt = href->pic_order_cnt,
                .flags = (ref->display_order < pic->display_order ?
                          VA_PICTURE_HEVC_RPS_ST_CURR_BEFORE : 0) |
                          (ref->display_order > pic->display_order ?
                          VA_PICTURE_HEVC_RPS_ST_CURR_AFTER  : 0),
            };
        }
    }

    for (; j < FF_ARRAY_ELEMS(vpic->reference_frames); j++) {
        vpic->reference_frames[j] = (VAPictureHEVC) {
            .picture_id = VA_INVALID_ID,
            .flags      = VA_PICTURE_HEVC_INVALID,
        };
    }

    vpic->coded_buf = pic->output_buffer;

    vpic->nal_unit_type = hpic->slice_nal_unit;

    switch (pic->type) {
    case PICTURE_TYPE_IDR:
        vpic->pic_fields.bits.idr_pic_flag       = 1;
        vpic->pic_fields.bits.coding_type        = 1;
        vpic->pic_fields.bits.reference_pic_flag = 1;
        break;
    case PICTURE_TYPE_I:
        vpic->pic_fields.bits.idr_pic_flag       = 0;
        vpic->pic_fields.bits.coding_type        = 1;
        vpic->pic_fields.bits.reference_pic_flag = 1;
        break;
    case PICTURE_TYPE_P:
        vpic->pic_fields.bits.idr_pic_flag       = 0;
        vpic->pic_fields.bits.coding_type        = 2;
        vpic->pic_fields.bits.reference_pic_flag = 1;
        break;
    case PICTURE_TYPE_B:
        vpic->pic_fields.bits.idr_pic_flag       = 0;
        vpic->pic_fields.bits.coding_type        = 3;
        vpic->pic_fields.bits.reference_pic_flag = 0;
        break;
    default:
        av_assert0(0 && "invalid picture type");
    }

    return 0;
}

static int vaapi_encode_h265_init_slice_params(AVCodecContext *avctx,
                                               VAAPIEncodePicture *pic,
                                               VAAPIEncodeSlice *slice)
{
    VAAPIEncodeContext                *ctx = avctx->priv_data;
    VAAPIEncodeH265Context           *priv = avctx->priv_data;
    VAAPIEncodeH265Picture           *hpic = pic->priv_data;
    const H265RawSPS                  *sps = &priv->raw_sps;
    const H265RawPPS                  *pps = &priv->raw_pps;
    H265RawSliceHeader                 *sh = &priv->raw_slice.header;
    VAEncPictureParameterBufferHEVC  *vpic = pic->codec_picture_params;
    VAEncSliceParameterBufferHEVC  *vslice = slice->codec_slice_params;
    int i;

    sh->nal_unit_header = (H265RawNALUnitHeader) {
        .nal_unit_type         = hpic->slice_nal_unit,
        .nuh_layer_id          = 0,
        .nuh_temporal_id_plus1 = 1,
    };

    sh->slice_pic_parameter_set_id      = pps->pps_pic_parameter_set_id;

    sh->first_slice_segment_in_pic_flag = slice->index == 0;
    sh->slice_segment_address           = slice->block_start;

    sh->slice_type = hpic->slice_type;

    if (sh->slice_type == HEVC_SLICE_P && ctx->p_to_gpb)
        sh->slice_type = HEVC_SLICE_B;

    sh->slice_pic_order_cnt_lsb = hpic->pic_order_cnt &
        (1 << (sps->log2_max_pic_order_cnt_lsb_minus4 + 4)) - 1;

    if (pic->type != PICTURE_TYPE_IDR) {
        H265RawSTRefPicSet *rps;
        const VAAPIEncodeH265Picture *strp;
        int rps_poc[MAX_DPB_SIZE];
        int rps_used[MAX_DPB_SIZE];
        int i, j, poc, rps_pics;

        sh->short_term_ref_pic_set_sps_flag = 0;

        rps = &sh->short_term_ref_pic_set;
        memset(rps, 0, sizeof(*rps));

        rps_pics = 0;
        for (i = 0; i < MAX_REFERENCE_LIST_NUM; i++) {
            for (j = 0; j < pic->nb_refs[i]; j++) {
                strp = pic->refs[i][j]->priv_data;
                rps_poc[rps_pics]  = strp->pic_order_cnt;
                rps_used[rps_pics] = 1;
                ++rps_pics;
            }
        }

        for (i = 0; i < pic->nb_dpb_pics; i++) {
            if (pic->dpb[i] == pic)
                continue;

            for (j = 0; j < pic->nb_refs[0]; j++) {
                if (pic->dpb[i] == pic->refs[0][j])
                    break;
            }
            if (j < pic->nb_refs[0])
                continue;

            for (j = 0; j < pic->nb_refs[1]; j++) {
                if (pic->dpb[i] == pic->refs[1][j])
                    break;
            }
            if (j < pic->nb_refs[1])
                continue;

            strp = pic->dpb[i]->priv_data;
            rps_poc[rps_pics]  = strp->pic_order_cnt;
            rps_used[rps_pics] = 0;
            ++rps_pics;
        }

        for (i = 1; i < rps_pics; i++) {
            for (j = i; j > 0; j--) {
                if (rps_poc[j] > rps_poc[j - 1])
                    break;
                av_assert0(rps_poc[j] != rps_poc[j - 1]);
                FFSWAP(int, rps_poc[j],  rps_poc[j - 1]);
                FFSWAP(int, rps_used[j], rps_used[j - 1]);
            }
        }

        av_log(avctx, AV_LOG_DEBUG, "RPS for POC %d:",
               hpic->pic_order_cnt);
        for (i = 0; i < rps_pics; i++) {
            av_log(avctx, AV_LOG_DEBUG, " (%d,%d)",
                   rps_poc[i], rps_used[i]);
        }
        av_log(avctx, AV_LOG_DEBUG, "\n");

        for (i = 0; i < rps_pics; i++) {
            av_assert0(rps_poc[i] != hpic->pic_order_cnt);
            if (rps_poc[i] > hpic->pic_order_cnt)
                break;
        }

        rps->num_negative_pics = i;
        poc = hpic->pic_order_cnt;
        for (j = i - 1; j >= 0; j--) {
            rps->delta_poc_s0_minus1[i - 1 - j] = poc - rps_poc[j] - 1;
            rps->used_by_curr_pic_s0_flag[i - 1 - j] = rps_used[j];
            poc = rps_poc[j];
        }

        rps->num_positive_pics = rps_pics - i;
        poc = hpic->pic_order_cnt;
        for (j = i; j < rps_pics; j++) {
            rps->delta_poc_s1_minus1[j - i] = rps_poc[j] - poc - 1;
            rps->used_by_curr_pic_s1_flag[j - i] = rps_used[j];
            poc = rps_poc[j];
        }

        sh->num_long_term_sps  = 0;
        sh->num_long_term_pics = 0;

        // when this flag is not present, it is inerred to 1.
        sh->collocated_from_l0_flag = 1;
        sh->slice_temporal_mvp_enabled_flag =
            sps->sps_temporal_mvp_enabled_flag;
        if (sh->slice_temporal_mvp_enabled_flag) {
            if (sh->slice_type == HEVC_SLICE_B)
                sh->collocated_from_l0_flag = 1;
            sh->collocated_ref_idx      = 0;
        }

        sh->num_ref_idx_active_override_flag = 0;
        sh->num_ref_idx_l0_active_minus1 = pps->num_ref_idx_l0_default_active_minus1;
        sh->num_ref_idx_l1_active_minus1 = pps->num_ref_idx_l1_default_active_minus1;
    }

    sh->slice_sao_luma_flag = sh->slice_sao_chroma_flag =
        sps->sample_adaptive_offset_enabled_flag;

    if (pic->type == PICTURE_TYPE_B)
        sh->slice_qp_delta = priv->fixed_qp_b - (pps->init_qp_minus26 + 26);
    else if (pic->type == PICTURE_TYPE_P)
        sh->slice_qp_delta = priv->fixed_qp_p - (pps->init_qp_minus26 + 26);
    else
        sh->slice_qp_delta = priv->fixed_qp_idr - (pps->init_qp_minus26 + 26);


    *vslice = (VAEncSliceParameterBufferHEVC) {
        .slice_segment_address = sh->slice_segment_address,
        .num_ctu_in_slice      = slice->block_size,

        .slice_type                 = sh->slice_type,
        .slice_pic_parameter_set_id = sh->slice_pic_parameter_set_id,

        .num_ref_idx_l0_active_minus1 = sh->num_ref_idx_l0_active_minus1,
        .num_ref_idx_l1_active_minus1 = sh->num_ref_idx_l1_active_minus1,

        .luma_log2_weight_denom         = sh->luma_log2_weight_denom,
        .delta_chroma_log2_weight_denom = sh->delta_chroma_log2_weight_denom,

        .max_num_merge_cand = 5 - sh->five_minus_max_num_merge_cand,

        .slice_qp_delta     = sh->slice_qp_delta,
        .slice_cb_qp_offset = sh->slice_cb_qp_offset,
        .slice_cr_qp_offset = sh->slice_cr_qp_offset,

        .slice_beta_offset_div2 = sh->slice_beta_offset_div2,
        .slice_tc_offset_div2   = sh->slice_tc_offset_div2,

        .slice_fields.bits = {
            .last_slice_of_pic_flag       = slice->index == pic->nb_slices - 1,
            .dependent_slice_segment_flag = sh->dependent_slice_segment_flag,
            .colour_plane_id              = sh->colour_plane_id,
            .slice_temporal_mvp_enabled_flag =
                sh->slice_temporal_mvp_enabled_flag,
            .slice_sao_luma_flag          = sh->slice_sao_luma_flag,
            .slice_sao_chroma_flag        = sh->slice_sao_chroma_flag,
            .num_ref_idx_active_override_flag =
                sh->num_ref_idx_active_override_flag,
            .mvd_l1_zero_flag             = sh->mvd_l1_zero_flag,
            .cabac_init_flag              = sh->cabac_init_flag,
            .slice_deblocking_filter_disabled_flag =
                sh->slice_deblocking_filter_disabled_flag,
            .slice_loop_filter_across_slices_enabled_flag =
                sh->slice_loop_filter_across_slices_enabled_flag,
            .collocated_from_l0_flag      = sh->collocated_from_l0_flag,
        },
    };

    for (i = 0; i < FF_ARRAY_ELEMS(vslice->ref_pic_list0); i++) {
        vslice->ref_pic_list0[i].picture_id = VA_INVALID_ID;
        vslice->ref_pic_list0[i].flags      = VA_PICTURE_HEVC_INVALID;
        vslice->ref_pic_list1[i].picture_id = VA_INVALID_ID;
        vslice->ref_pic_list1[i].flags      = VA_PICTURE_HEVC_INVALID;
    }

    if (pic->nb_refs[0]) {
        // Backward reference for P- or B-frame.
        av_assert0(pic->type == PICTURE_TYPE_P ||
                   pic->type == PICTURE_TYPE_B);
        vslice->ref_pic_list0[0] = vpic->reference_frames[0];
        if (ctx->p_to_gpb && pic->type == PICTURE_TYPE_P)
            // Reference for GPB B-frame, L0 == L1
            vslice->ref_pic_list1[0] = vpic->reference_frames[0];
    }
    if (pic->nb_refs[1]) {
        // Forward reference for B-frame.
        av_assert0(pic->type == PICTURE_TYPE_B);
        vslice->ref_pic_list1[0] = vpic->reference_frames[1];
    }

    if (pic->type == PICTURE_TYPE_P && ctx->p_to_gpb) {
        vslice->slice_type = HEVC_SLICE_B;
        for (i = 0; i < FF_ARRAY_ELEMS(vslice->ref_pic_list0); i++) {
            vslice->ref_pic_list1[i].picture_id = vslice->ref_pic_list0[i].picture_id;
            vslice->ref_pic_list1[i].flags      = vslice->ref_pic_list0[i].flags;
        }
    }

    return 0;
}

static av_cold int vaapi_encode_h265_get_encoder_caps(AVCodecContext *avctx)
{
    VAAPIEncodeContext      *ctx = avctx->priv_data;
    VAAPIEncodeH265Context *priv = avctx->priv_data;

#if VA_CHECK_VERSION(1, 13, 0)
    {
        VAConfigAttribValEncHEVCBlockSizes block_size;
        VAConfigAttrib attr;
        VAStatus vas;

        attr.type = VAConfigAttribEncHEVCFeatures;
        vas = vaGetConfigAttributes(ctx->hwctx->display, ctx->va_profile,
                                    ctx->va_entrypoint, &attr, 1);
        if (vas != VA_STATUS_SUCCESS) {
            av_log(avctx, AV_LOG_ERROR, "Failed to query encoder "
                   "features, using guessed defaults.\n");
            return AVERROR_EXTERNAL;
        } else if (attr.value == VA_ATTRIB_NOT_SUPPORTED) {
            av_log(avctx, AV_LOG_WARNING, "Driver does not advertise "
                   "encoder features, using guessed defaults.\n");
        } else {
            priv->va_features = attr.value;
        }

        attr.type = VAConfigAttribEncHEVCBlockSizes;
        vas = vaGetConfigAttributes(ctx->hwctx->display, ctx->va_profile,
                                    ctx->va_entrypoint, &attr, 1);
        if (vas != VA_STATUS_SUCCESS) {
            av_log(avctx, AV_LOG_ERROR, "Failed to query encoder "
                   "block size, using guessed defaults.\n");
            return AVERROR_EXTERNAL;
        } else if (attr.value == VA_ATTRIB_NOT_SUPPORTED) {
            av_log(avctx, AV_LOG_WARNING, "Driver does not advertise "
                   "encoder block size, using guessed defaults.\n");
        } else {
            priv->va_bs = block_size.value = attr.value;

            priv->ctu_size =
                1 << block_size.bits.log2_max_coding_tree_block_size_minus3 + 3;
            priv->min_cb_size =
                1 << block_size.bits.log2_min_luma_coding_block_size_minus3 + 3;
        }
    }
#endif

    if (!priv->ctu_size) {
        priv->ctu_size     = 32;
        priv->min_cb_size  = 16;
    }
    av_log(avctx, AV_LOG_VERBOSE, "Using CTU size %dx%d, "
           "min CB size %dx%d.\n", priv->ctu_size, priv->ctu_size,
           priv->min_cb_size, priv->min_cb_size);

    ctx->surface_width  = FFALIGN(avctx->width,  priv->min_cb_size);
    ctx->surface_height = FFALIGN(avctx->height, priv->min_cb_size);

    ctx->slice_block_width = ctx->slice_block_height = priv->ctu_size;

    return 0;
}

static av_cold int vaapi_encode_h265_configure(AVCodecContext *avctx)
{
    VAAPIEncodeContext      *ctx = avctx->priv_data;
    VAAPIEncodeH265Context *priv = avctx->priv_data;
    int err;

    err = ff_cbs_init(&priv->cbc, AV_CODEC_ID_HEVC, avctx);
    if (err < 0)
        return err;

    if (ctx->va_rc_mode == VA_RC_CQP) {
        // Note that VAAPI only supports positive QP values - the range is
        // therefore always bounded below by 1, even in 10-bit mode where
        // it should go down to -12.

        priv->fixed_qp_p = av_clip(ctx->rc_quality, 1, 51);
        if (avctx->i_quant_factor > 0.0)
            priv->fixed_qp_idr =
                av_clip((avctx->i_quant_factor * priv->fixed_qp_p +
                         avctx->i_quant_offset) + 0.5, 1, 51);
        else
            priv->fixed_qp_idr = priv->fixed_qp_p;
        if (avctx->b_quant_factor > 0.0)
            priv->fixed_qp_b =
                av_clip((avctx->b_quant_factor * priv->fixed_qp_p +
                         avctx->b_quant_offset) + 0.5, 1, 51);
        else
            priv->fixed_qp_b = priv->fixed_qp_p;

        av_log(avctx, AV_LOG_DEBUG, "Using fixed QP = "
               "%d / %d / %d for IDR- / P- / B-frames.\n",
               priv->fixed_qp_idr, priv->fixed_qp_p, priv->fixed_qp_b);

    } else {
        // These still need to be set for init_qp/slice_qp_delta.
        priv->fixed_qp_idr = 30;
        priv->fixed_qp_p   = 30;
        priv->fixed_qp_b   = 30;
    }

    ctx->roi_quant_range = 51 + 6 * (ctx->profile->depth - 8);

    return 0;
}

static const VAAPIEncodeProfile vaapi_encode_h265_profiles[] = {
    { AV_PROFILE_HEVC_MAIN,     8, 3, 1, 1, VAProfileHEVCMain       },
    { AV_PROFILE_HEVC_REXT,     8, 3, 1, 1, VAProfileHEVCMain       },
#if VA_CHECK_VERSION(0, 37, 0)
    { AV_PROFILE_HEVC_MAIN_10, 10, 3, 1, 1, VAProfileHEVCMain10     },
    { AV_PROFILE_HEVC_REXT,    10, 3, 1, 1, VAProfileHEVCMain10     },
#endif
#if VA_CHECK_VERSION(1, 2, 0)
    { AV_PROFILE_HEVC_REXT,    12, 3, 1, 1, VAProfileHEVCMain12 },
    { AV_PROFILE_HEVC_REXT,     8, 3, 1, 0, VAProfileHEVCMain422_10 },
    { AV_PROFILE_HEVC_REXT,    10, 3, 1, 0, VAProfileHEVCMain422_10 },
    { AV_PROFILE_HEVC_REXT,    12, 3, 1, 0, VAProfileHEVCMain422_12 },
    { AV_PROFILE_HEVC_REXT,     8, 3, 0, 0, VAProfileHEVCMain444 },
    { AV_PROFILE_HEVC_REXT,    10, 3, 0, 0, VAProfileHEVCMain444_10 },
    { AV_PROFILE_HEVC_REXT,    12, 3, 0, 0, VAProfileHEVCMain444_12 },
#endif
    { AV_PROFILE_UNKNOWN }
};

static const VAAPIEncodeType vaapi_encode_type_h265 = {
    .profiles              = vaapi_encode_h265_profiles,

    .flags                 = FLAG_SLICE_CONTROL |
                             FLAG_B_PICTURES |
                             FLAG_B_PICTURE_REFERENCES |
                             FLAG_NON_IDR_KEY_PICTURES,

    .default_quality       = 25,

    .get_encoder_caps      = &vaapi_encode_h265_get_encoder_caps,
    .configure             = &vaapi_encode_h265_configure,

    .picture_priv_data_size = sizeof(VAAPIEncodeH265Picture),

    .sequence_params_size  = sizeof(VAEncSequenceParameterBufferHEVC),
    .init_sequence_params  = &vaapi_encode_h265_init_sequence_params,

    .picture_params_size   = sizeof(VAEncPictureParameterBufferHEVC),
    .init_picture_params   = &vaapi_encode_h265_init_picture_params,

    .slice_params_size     = sizeof(VAEncSliceParameterBufferHEVC),
    .init_slice_params     = &vaapi_encode_h265_init_slice_params,

    .sequence_header_type  = VAEncPackedHeaderSequence,
    .write_sequence_header = &vaapi_encode_h265_write_sequence_header,

    .slice_header_type     = VAEncPackedHeaderHEVC_Slice,
    .write_slice_header    = &vaapi_encode_h265_write_slice_header,

    .write_extra_header    = &vaapi_encode_h265_write_extra_header,
};

static av_cold int vaapi_encode_h265_init(AVCodecContext *avctx)
{
    VAAPIEncodeContext      *ctx = avctx->priv_data;
    VAAPIEncodeH265Context *priv = avctx->priv_data;

    ctx->codec = &vaapi_encode_type_h265;

    if (avctx->profile == AV_PROFILE_UNKNOWN)
        avctx->profile = priv->profile;
    if (avctx->level == AV_LEVEL_UNKNOWN)
        avctx->level = priv->level;

    if (avctx->level != AV_LEVEL_UNKNOWN && avctx->level & ~0xff) {
        av_log(avctx, AV_LOG_ERROR, "Invalid level %d: must fit "
               "in 8-bit unsigned integer.\n", avctx->level);
        return AVERROR(EINVAL);
    }

    ctx->desired_packed_headers =
        VA_ENC_PACKED_HEADER_SEQUENCE | // VPS, SPS and PPS.
        VA_ENC_PACKED_HEADER_SLICE    | // Slice headers.
        VA_ENC_PACKED_HEADER_MISC;      // SEI

    if (priv->qp > 0)
        ctx->explicit_qp = priv->qp;

    return ff_vaapi_encode_init(avctx);
}

static av_cold int vaapi_encode_h265_close(AVCodecContext *avctx)
{
    VAAPIEncodeH265Context *priv = avctx->priv_data;

    ff_cbs_fragment_free(&priv->current_access_unit);
    ff_cbs_close(&priv->cbc);
    av_freep(&priv->sei_a53cc_data);

    return ff_vaapi_encode_close(avctx);
}

#define OFFSET(x) offsetof(VAAPIEncodeH265Context, x)
#define FLAGS (AV_OPT_FLAG_VIDEO_PARAM | AV_OPT_FLAG_ENCODING_PARAM)
static const AVOption vaapi_encode_h265_options[] = {
    VAAPI_ENCODE_COMMON_OPTIONS,
    VAAPI_ENCODE_RC_OPTIONS,

    { "qp", "Constant QP (for P-frames; scaled by qfactor/qoffset for I/B)",
      OFFSET(qp), AV_OPT_TYPE_INT, { .i64 = 0 }, 0, 52, FLAGS },

    { "aud", "Include AUD",
      OFFSET(aud), AV_OPT_TYPE_BOOL, { .i64 = 0 }, 0, 1, FLAGS },

    { "profile", "Set profile (general_profile_idc)",
      OFFSET(profile), AV_OPT_TYPE_INT,
      { .i64 = AV_PROFILE_UNKNOWN }, AV_PROFILE_UNKNOWN, 0xff, FLAGS, .unit = "profile" },

#define PROFILE(name, value)  name, NULL, 0, AV_OPT_TYPE_CONST, \
      { .i64 = value }, 0, 0, FLAGS, .unit = "profile"
    { PROFILE("main",               AV_PROFILE_HEVC_MAIN) },
    { PROFILE("main10",             AV_PROFILE_HEVC_MAIN_10) },
    { PROFILE("rext",               AV_PROFILE_HEVC_REXT) },
#undef PROFILE

    { "tier", "Set tier (general_tier_flag)",
      OFFSET(tier), AV_OPT_TYPE_INT,
      { .i64 = 0 }, 0, 1, FLAGS, .unit = "tier" },
    { "main", NULL, 0, AV_OPT_TYPE_CONST,
      { .i64 = 0 }, 0, 0, FLAGS, .unit = "tier" },
    { "high", NULL, 0, AV_OPT_TYPE_CONST,
      { .i64 = 1 }, 0, 0, FLAGS, .unit = "tier" },

    { "level", "Set level (general_level_idc)",
      OFFSET(level), AV_OPT_TYPE_INT,
      { .i64 = AV_LEVEL_UNKNOWN }, AV_LEVEL_UNKNOWN, 0xff, FLAGS, .unit = "level" },

#define LEVEL(name, value) name, NULL, 0, AV_OPT_TYPE_CONST, \
      { .i64 = value }, 0, 0, FLAGS, .unit = "level"
    { LEVEL("1",    30) },
    { LEVEL("2",    60) },
    { LEVEL("2.1",  63) },
    { LEVEL("3",    90) },
    { LEVEL("3.1",  93) },
    { LEVEL("4",   120) },
    { LEVEL("4.1", 123) },
    { LEVEL("5",   150) },
    { LEVEL("5.1", 153) },
    { LEVEL("5.2", 156) },
    { LEVEL("6",   180) },
    { LEVEL("6.1", 183) },
    { LEVEL("6.2", 186) },
#undef LEVEL

    { "sei", "Set SEI to include",
      OFFSET(sei), AV_OPT_TYPE_FLAGS,
      { .i64 = SEI_MASTERING_DISPLAY | SEI_CONTENT_LIGHT_LEVEL | SEI_A53_CC },
      0, INT_MAX, FLAGS, .unit = "sei" },
    { "hdr",
      "Include HDR metadata for mastering display colour volume "
      "and content light level information",
      0, AV_OPT_TYPE_CONST,
      { .i64 = SEI_MASTERING_DISPLAY | SEI_CONTENT_LIGHT_LEVEL },
      INT_MIN, INT_MAX, FLAGS, .unit = "sei" },
    { "a53_cc",
      "Include A/53 caption data",
      0, AV_OPT_TYPE_CONST,
      { .i64 = SEI_A53_CC },
      INT_MIN, INT_MAX, FLAGS, .unit = "sei" },

    { "tiles", "Tile columns x rows",
      OFFSET(common.tile_cols), AV_OPT_TYPE_IMAGE_SIZE,
      { .str = NULL }, 0, 0, FLAGS },

    { NULL },
};

static const FFCodecDefault vaapi_encode_h265_defaults[] = {
    { "b",              "0"   },
    { "bf",             "2"   },
    { "g",              "120" },
    { "i_qfactor",      "1"   },
    { "i_qoffset",      "0"   },
    { "b_qfactor",      "6/5" },
    { "b_qoffset",      "0"   },
    { "qmin",           "-1"  },
    { "qmax",           "-1"  },
    { NULL },
};

static const AVClass vaapi_encode_h265_class = {
    .class_name = "h265_vaapi",
    .item_name  = av_default_item_name,
    .option     = vaapi_encode_h265_options,
    .version    = LIBAVUTIL_VERSION_INT,
};

const FFCodec ff_hevc_vaapi_encoder = {
    .p.name         = "hevc_vaapi",
    CODEC_LONG_NAME("H.265/HEVC (VAAPI)"),
    .p.type         = AVMEDIA_TYPE_VIDEO,
    .p.id           = AV_CODEC_ID_HEVC,
    .priv_data_size = sizeof(VAAPIEncodeH265Context),
    .init           = &vaapi_encode_h265_init,
    FF_CODEC_RECEIVE_PACKET_CB(&ff_vaapi_encode_receive_packet),
    .close          = &vaapi_encode_h265_close,
    .p.priv_class   = &vaapi_encode_h265_class,
    .p.capabilities = AV_CODEC_CAP_DELAY | AV_CODEC_CAP_HARDWARE |
                      AV_CODEC_CAP_DR1 | AV_CODEC_CAP_ENCODER_REORDERED_OPAQUE,
    .caps_internal  = FF_CODEC_CAP_NOT_INIT_THREADSAFE |
                      FF_CODEC_CAP_INIT_CLEANUP,
    .defaults       = vaapi_encode_h265_defaults,
    .p.pix_fmts = (const enum AVPixelFormat[]) {
        AV_PIX_FMT_VAAPI,
        AV_PIX_FMT_NONE,
    },
    .hw_configs     = ff_vaapi_encode_hw_configs,
    .p.wrapper_name = "vaapi",
};