/*

  * 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 <va/va.h>
 #include <va/va_enc_h264.h>
 
 #include "libavutil/avassert.h"
 #include "libavutil/internal.h"
 #include "libavutil/opt.h"
 #include "libavutil/pixfmt.h"
 
 #include "avcodec.h"
 #include "h264.h"
 #include "internal.h"
 #include "vaapi_encode.h"
 #include "vaapi_encode_h26x.h"
 
 enum {
     SLICE_TYPE_P  = 0,
     SLICE_TYPE_B  = 1,
     SLICE_TYPE_I  = 2,
     SLICE_TYPE_SP = 3,
     SLICE_TYPE_SI = 4,
 };
 
 // This structure contains all possibly-useful per-sequence syntax elements
 // which are not already contained in the various VAAPI structures.
 typedef struct VAAPIEncodeH264MiscSequenceParams {
     unsigned int profile_idc;
     char constraint_set0_flag;
     char constraint_set1_flag;
     char constraint_set2_flag;
     char constraint_set3_flag;
     char constraint_set4_flag;
     char constraint_set5_flag;
 
     char separate_colour_plane_flag;
     char qpprime_y_zero_transform_bypass_flag;
 
     char gaps_in_frame_num_allowed_flag;
     char delta_pic_order_always_zero_flag;
     char bottom_field_pic_order_in_frame_present_flag;
 
     unsigned int num_slice_groups_minus1;
     unsigned int slice_group_map_type;
 
     int pic_init_qs_minus26;
 
     char vui_parameters_present_flag;
 } VAAPIEncodeH264MiscSequenceParams;
 
 // This structure contains all possibly-useful per-slice syntax elements
 // which are not already contained in the various VAAPI structures.
 typedef struct VAAPIEncodeH264MiscSliceParams {
     unsigned int nal_unit_type;
     unsigned int nal_ref_idc;
 
     unsigned int colour_plane_id;
     char field_pic_flag;
     char bottom_field_flag;
 
     unsigned int redundant_pic_cnt;
 
     char sp_for_switch_flag;
     int slice_qs_delta;
 
     char ref_pic_list_modification_flag_l0;
     char ref_pic_list_modification_flag_l1;
 
     char no_output_of_prior_pics_flag;
     char long_term_reference_flag;
     char adaptive_ref_pic_marking_mode_flag;
 } VAAPIEncodeH264MiscSliceParams;
 
 typedef struct VAAPIEncodeH264Slice {
     VAAPIEncodeH264MiscSliceParams misc_slice_params;
 } VAAPIEncodeH264Slice;
 
 typedef struct VAAPIEncodeH264Context {
     VAAPIEncodeH264MiscSequenceParams misc_sequence_params;
 
     int mb_width;
     int mb_height;
 
     int fixed_qp_idr;
     int fixed_qp_p;
     int fixed_qp_b;
 
     int64_t idr_pic_count;
     int64_t last_idr_frame;
 

     // Rate control configuration.
     struct {
         VAEncMiscParameterBuffer misc;
         VAEncMiscParameterRateControl rc;
     } rc_params;
     struct {
         VAEncMiscParameterBuffer misc;
         VAEncMiscParameterHRD hrd;
     } hrd_params;

 
 #if VA_CHECK_VERSION(0, 36, 0)
     // Speed-quality tradeoff setting.
     struct {
         VAEncMiscParameterBuffer misc;
         VAEncMiscParameterBufferQualityLevel quality;
     } quality_params;
 #endif

 } VAAPIEncodeH264Context;
 

 typedef struct VAAPIEncodeH264Options {
     int qp;

     int quality;

 } VAAPIEncodeH264Options;
 

 
 #define vseq_var(name)     vseq->name, name
 #define vseq_field(name)   vseq->seq_fields.bits.name, name
 #define vpic_var(name)     vpic->name, name
 #define vpic_field(name)   vpic->pic_fields.bits.name, name
 #define vslice_var(name)   vslice->name, name
 #define vslice_field(name) vslice->slice_fields.bits.name, name
 #define mseq_var(name)     mseq->name, name
 #define mslice_var(name)   mslice->name, name
 
 static void vaapi_encode_h264_write_nal_header(PutBitContext *pbc,
                                                int nal_unit_type, int nal_ref_idc)
 {
     u(1, 0, forbidden_zero_bit);
     u(2, nal_ref_idc, nal_ref_idc);
     u(5, nal_unit_type, nal_unit_type);
 }
 
 static void vaapi_encode_h264_write_trailing_rbsp(PutBitContext *pbc)
 {
     u(1, 1, rbsp_stop_one_bit);
     while (put_bits_count(pbc) & 7)
         u(1, 0, rbsp_alignment_zero_bit);
 }
 
 static void vaapi_encode_h264_write_sps(PutBitContext *pbc,
                                         VAAPIEncodeContext *ctx)
 {
     VAEncSequenceParameterBufferH264  *vseq = ctx->codec_sequence_params;
     VAAPIEncodeH264Context            *priv = ctx->priv_data;
     VAAPIEncodeH264MiscSequenceParams *mseq = &priv->misc_sequence_params;
     int i;
 
     vaapi_encode_h264_write_nal_header(pbc, NAL_SPS, 3);
 
     u(8, mseq_var(profile_idc));
     u(1, mseq_var(constraint_set0_flag));
     u(1, mseq_var(constraint_set1_flag));
     u(1, mseq_var(constraint_set2_flag));
     u(1, mseq_var(constraint_set3_flag));
     u(1, mseq_var(constraint_set4_flag));
     u(1, mseq_var(constraint_set5_flag));
     u(2, 0, reserved_zero_2bits);
 
     u(8, vseq_var(level_idc));
 
     ue(vseq_var(seq_parameter_set_id));
 
     if (mseq->profile_idc == 100 || mseq->profile_idc == 110 ||
         mseq->profile_idc == 122 || mseq->profile_idc == 244 ||
         mseq->profile_idc ==  44 || mseq->profile_idc ==  83 ||
         mseq->profile_idc ==  86 || mseq->profile_idc == 118 ||
         mseq->profile_idc == 128 || mseq->profile_idc == 138) {
         ue(vseq_field(chroma_format_idc));
 
         if (vseq->seq_fields.bits.chroma_format_idc == 3)
             u(1, mseq_var(separate_colour_plane_flag));
 
         ue(vseq_var(bit_depth_luma_minus8));
         ue(vseq_var(bit_depth_chroma_minus8));
 
         u(1, mseq_var(qpprime_y_zero_transform_bypass_flag));
 
         u(1, vseq_field(seq_scaling_matrix_present_flag));
         if (vseq->seq_fields.bits.seq_scaling_matrix_present_flag) {
             av_assert0(0 && "scaling matrices not supported");
         }
     }
 
     ue(vseq_field(log2_max_frame_num_minus4));
     ue(vseq_field(pic_order_cnt_type));
 
     if (vseq->seq_fields.bits.pic_order_cnt_type == 0) {
         ue(vseq_field(log2_max_pic_order_cnt_lsb_minus4));
     } else if (vseq->seq_fields.bits.pic_order_cnt_type == 1) {
         u(1, mseq_var(delta_pic_order_always_zero_flag));
         se(vseq_var(offset_for_non_ref_pic));
         se(vseq_var(offset_for_top_to_bottom_field));
         ue(vseq_var(num_ref_frames_in_pic_order_cnt_cycle));
 
         for (i = 0; i < vseq->num_ref_frames_in_pic_order_cnt_cycle; i++)
             se(vseq_var(offset_for_ref_frame[i]));
     }
 
     ue(vseq_var(max_num_ref_frames));
     u(1, mseq_var(gaps_in_frame_num_allowed_flag));
 
     ue(vseq->picture_width_in_mbs  - 1, pic_width_in_mbs_minus1);
     ue(vseq->picture_height_in_mbs - 1, pic_height_in_mbs_minus1);
 
     u(1, vseq_field(frame_mbs_only_flag));
     if (!vseq->seq_fields.bits.frame_mbs_only_flag)
         u(1, vseq_field(mb_adaptive_frame_field_flag));
 
     u(1, vseq_field(direct_8x8_inference_flag));
 
     u(1, vseq_var(frame_cropping_flag));
     if (vseq->frame_cropping_flag) {
         ue(vseq_var(frame_crop_left_offset));
         ue(vseq_var(frame_crop_right_offset));
         ue(vseq_var(frame_crop_top_offset));
         ue(vseq_var(frame_crop_bottom_offset));
     }
 
     u(1, mseq_var(vui_parameters_present_flag));
 
     vaapi_encode_h264_write_trailing_rbsp(pbc);
 }
 
 static void vaapi_encode_h264_write_pps(PutBitContext *pbc,
                                         VAAPIEncodeContext *ctx)
 {
     VAEncPictureParameterBufferH264   *vpic = ctx->codec_picture_params;
     VAAPIEncodeH264Context            *priv = ctx->priv_data;
     VAAPIEncodeH264MiscSequenceParams *mseq = &priv->misc_sequence_params;
 
     vaapi_encode_h264_write_nal_header(pbc, NAL_PPS, 3);
 
     ue(vpic_var(pic_parameter_set_id));
     ue(vpic_var(seq_parameter_set_id));
 
     u(1, vpic_field(entropy_coding_mode_flag));
     u(1, mseq_var(bottom_field_pic_order_in_frame_present_flag));
 
     ue(mseq_var(num_slice_groups_minus1));
     if (mseq->num_slice_groups_minus1 > 0) {
         ue(mseq_var(slice_group_map_type));
         av_assert0(0 && "slice groups not supported");
     }
 
     ue(vpic_var(num_ref_idx_l0_active_minus1));
     ue(vpic_var(num_ref_idx_l1_active_minus1));
 
     u(1, vpic_field(weighted_pred_flag));
     u(2, vpic_field(weighted_bipred_idc));
 
     se(vpic->pic_init_qp - 26, pic_init_qp_minus26);
     se(mseq_var(pic_init_qs_minus26));
     se(vpic_var(chroma_qp_index_offset));
 
     u(1, vpic_field(deblocking_filter_control_present_flag));
     u(1, vpic_field(constrained_intra_pred_flag));
     u(1, vpic_field(redundant_pic_cnt_present_flag));
     u(1, vpic_field(transform_8x8_mode_flag));
 
     u(1, vpic_field(pic_scaling_matrix_present_flag));
     if (vpic->pic_fields.bits.pic_scaling_matrix_present_flag) {
         av_assert0(0 && "scaling matrices not supported");
     }
 
     se(vpic_var(second_chroma_qp_index_offset));
 
     vaapi_encode_h264_write_trailing_rbsp(pbc);
 }
 
 static void vaapi_encode_h264_write_slice_header2(PutBitContext *pbc,
                                                   VAAPIEncodeContext *ctx,
                                                   VAAPIEncodePicture *pic,
                                                   VAAPIEncodeSlice *slice)
 {
     VAEncSequenceParameterBufferH264  *vseq = ctx->codec_sequence_params;
     VAEncPictureParameterBufferH264   *vpic = pic->codec_picture_params;
     VAEncSliceParameterBufferH264   *vslice = slice->codec_slice_params;
     VAAPIEncodeH264Context            *priv = ctx->priv_data;
     VAAPIEncodeH264MiscSequenceParams *mseq = &priv->misc_sequence_params;
     VAAPIEncodeH264Slice            *pslice = slice->priv_data;
     VAAPIEncodeH264MiscSliceParams  *mslice = &pslice->misc_slice_params;
 
     vaapi_encode_h264_write_nal_header(pbc, mslice->nal_unit_type,
                                        mslice->nal_ref_idc);
 
     ue(vslice->macroblock_address, first_mb_in_slice);
     ue(vslice_var(slice_type));
     ue(vpic_var(pic_parameter_set_id));
 
     if (mseq->separate_colour_plane_flag) {
         u(2, mslice_var(colour_plane_id));
     }
 
     u(4 + vseq->seq_fields.bits.log2_max_frame_num_minus4,
       (vpic->frame_num &
        ((1 << (4 + vseq->seq_fields.bits.log2_max_frame_num_minus4)) - 1)),
       frame_num);
 
     if (!vseq->seq_fields.bits.frame_mbs_only_flag) {
         u(1, mslice_var(field_pic_flag));
         if (mslice->field_pic_flag)
             u(1, mslice_var(bottom_field_flag));
     }
 
     if (vpic->pic_fields.bits.idr_pic_flag) {
         ue(vslice_var(idr_pic_id));
     }
 
     if (vseq->seq_fields.bits.pic_order_cnt_type == 0) {
         u(4 + vseq->seq_fields.bits.log2_max_pic_order_cnt_lsb_minus4,
           vslice_var(pic_order_cnt_lsb));
         if (mseq->bottom_field_pic_order_in_frame_present_flag &&
             !mslice->field_pic_flag) {
             se(vslice_var(delta_pic_order_cnt_bottom));
         }
     }
 
     if (vseq->seq_fields.bits.pic_order_cnt_type == 1 &&
         !vseq->seq_fields.bits.delta_pic_order_always_zero_flag) {
         se(vslice_var(delta_pic_order_cnt[0]));
         if (mseq->bottom_field_pic_order_in_frame_present_flag &&
             !mslice->field_pic_flag) {
             se(vslice_var(delta_pic_order_cnt[1]));
         }
     }
 
     if (vpic->pic_fields.bits.redundant_pic_cnt_present_flag) {
         ue(mslice_var(redundant_pic_cnt));
     }
 
     if (vslice->slice_type == SLICE_TYPE_B) {
         u(1, vslice_var(direct_spatial_mv_pred_flag));
     }
 
     if (vslice->slice_type == SLICE_TYPE_P ||
         vslice->slice_type == SLICE_TYPE_SP ||
         vslice->slice_type == SLICE_TYPE_B) {
         u(1, vslice_var(num_ref_idx_active_override_flag));
         if (vslice->num_ref_idx_active_override_flag) {
             ue(vslice_var(num_ref_idx_l0_active_minus1));
             if (vslice->slice_type == SLICE_TYPE_B)
                 ue(vslice_var(num_ref_idx_l1_active_minus1));
         }
     }
 
     if (mslice->nal_unit_type == 20 || mslice->nal_unit_type == 21) {
         av_assert0(0 && "no MVC support");
     } else {
         if (vslice->slice_type % 5 != 2 && vslice->slice_type % 5 != 4) {
             u(1, mslice_var(ref_pic_list_modification_flag_l0));
             if (mslice->ref_pic_list_modification_flag_l0) {
                 av_assert0(0 && "ref pic list modification");
             }
         }
         if (vslice->slice_type % 5 == 1) {
             u(1, mslice_var(ref_pic_list_modification_flag_l1));
             if (mslice->ref_pic_list_modification_flag_l1) {
                 av_assert0(0 && "ref pic list modification");
             }
         }
     }
 
     if ((vpic->pic_fields.bits.weighted_pred_flag &&
          (vslice->slice_type == SLICE_TYPE_P ||
           vslice->slice_type == SLICE_TYPE_SP)) ||
         (vpic->pic_fields.bits.weighted_bipred_idc == 1 &&
          vslice->slice_type == SLICE_TYPE_B)) {
         av_assert0(0 && "prediction weights not supported");
     }
 
     av_assert0(mslice->nal_ref_idc > 0 ==
                vpic->pic_fields.bits.reference_pic_flag);
     if (mslice->nal_ref_idc != 0) {
         if (vpic->pic_fields.bits.idr_pic_flag) {
             u(1, mslice_var(no_output_of_prior_pics_flag));
             u(1, mslice_var(long_term_reference_flag));
         } else {
             u(1, mslice_var(adaptive_ref_pic_marking_mode_flag));
             if (mslice->adaptive_ref_pic_marking_mode_flag) {
                 av_assert0(0 && "MMCOs not supported");
             }
         }
     }
 
     if (vpic->pic_fields.bits.entropy_coding_mode_flag &&
         vslice->slice_type != SLICE_TYPE_I &&
         vslice->slice_type != SLICE_TYPE_SI) {
         ue(vslice_var(cabac_init_idc));
     }
 
     se(vslice_var(slice_qp_delta));
     if (vslice->slice_type == SLICE_TYPE_SP ||
         vslice->slice_type == SLICE_TYPE_SI) {
         if (vslice->slice_type == SLICE_TYPE_SP)
             u(1, mslice_var(sp_for_switch_flag));
         se(mslice_var(slice_qs_delta));
     }
 
     if (vpic->pic_fields.bits.deblocking_filter_control_present_flag) {
         ue(vslice_var(disable_deblocking_filter_idc));
         if (vslice->disable_deblocking_filter_idc != 1) {
             se(vslice_var(slice_alpha_c0_offset_div2));
             se(vslice_var(slice_beta_offset_div2));
         }
     }
 
     if (mseq->num_slice_groups_minus1 > 0 &&
         mseq->slice_group_map_type >= 3 && mseq->slice_group_map_type <= 5) {
         av_assert0(0 && "slice groups not supported");
     }
 
     // No alignment - this need not be a byte boundary.
 }
 
 static int vaapi_encode_h264_write_sequence_header(AVCodecContext *avctx,
                                                    char *data, size_t *data_len)
 {
     VAAPIEncodeContext *ctx = avctx->priv_data;
     PutBitContext pbc;
     char tmp[256];
     int err;
     size_t nal_len, bit_len, bit_pos, next_len;
 
     bit_len = *data_len;
     bit_pos = 0;
 
     init_put_bits(&pbc, tmp, sizeof(tmp));
     vaapi_encode_h264_write_sps(&pbc, ctx);
     nal_len = put_bits_count(&pbc);
     flush_put_bits(&pbc);
 
     next_len = bit_len - bit_pos;
     err = ff_vaapi_encode_h26x_nal_unit_to_byte_stream(data + bit_pos / 8,
                                                        &next_len,
                                                        tmp, nal_len);
     if (err < 0)
         return err;
     bit_pos += next_len;
 
     init_put_bits(&pbc, tmp, sizeof(tmp));
     vaapi_encode_h264_write_pps(&pbc, ctx);
     nal_len = put_bits_count(&pbc);
     flush_put_bits(&pbc);
 
     next_len = bit_len - bit_pos;
     err = ff_vaapi_encode_h26x_nal_unit_to_byte_stream(data + bit_pos / 8,
                                                        &next_len,
                                                        tmp, nal_len);
     if (err < 0)
         return err;
     bit_pos += next_len;
 
     *data_len = bit_pos;
     return 0;
 }
 
 static int vaapi_encode_h264_write_slice_header(AVCodecContext *avctx,
                                                 VAAPIEncodePicture *pic,
                                                 VAAPIEncodeSlice *slice,
                                                 char *data, size_t *data_len)
 {
     VAAPIEncodeContext *ctx = avctx->priv_data;
     PutBitContext pbc;
     char tmp[256];
     size_t header_len;
 
     init_put_bits(&pbc, tmp, sizeof(tmp));
     vaapi_encode_h264_write_slice_header2(&pbc, ctx, pic, slice);
     header_len = put_bits_count(&pbc);
     flush_put_bits(&pbc);
 
     return ff_vaapi_encode_h26x_nal_unit_to_byte_stream(data, data_len,
                                                         tmp, header_len);
 }
 
 static int vaapi_encode_h264_init_sequence_params(AVCodecContext *avctx)
 {
     VAAPIEncodeContext                 *ctx = avctx->priv_data;
     VAEncSequenceParameterBufferH264  *vseq = ctx->codec_sequence_params;
     VAEncPictureParameterBufferH264   *vpic = ctx->codec_picture_params;
     VAAPIEncodeH264Context            *priv = ctx->priv_data;
     VAAPIEncodeH264MiscSequenceParams *mseq = &priv->misc_sequence_params;
     int i;
 
     {
         vseq->seq_parameter_set_id = 0;
 
         vseq->level_idc = avctx->level;
 
         vseq->max_num_ref_frames = 2;
 
         vseq->picture_width_in_mbs  = priv->mb_width;
         vseq->picture_height_in_mbs = priv->mb_height;
 
         vseq->seq_fields.bits.chroma_format_idc = 1;
         vseq->seq_fields.bits.frame_mbs_only_flag = 1;
         vseq->seq_fields.bits.direct_8x8_inference_flag = 1;
         vseq->seq_fields.bits.log2_max_frame_num_minus4 = 4;
         vseq->seq_fields.bits.pic_order_cnt_type = 0;
 
         if (ctx->input_width  != ctx->aligned_width ||
             ctx->input_height != ctx->aligned_height) {
             vseq->frame_cropping_flag = 1;
 
             vseq->frame_crop_left_offset   = 0;
             vseq->frame_crop_right_offset  =
                 (ctx->aligned_width - ctx->input_width) / 2;
             vseq->frame_crop_top_offset    = 0;
             vseq->frame_crop_bottom_offset =
                 (ctx->aligned_height - ctx->input_height) / 2;
         } else {
             vseq->frame_cropping_flag = 0;
         }

 
         vseq->bits_per_second = avctx->bit_rate;
         if (avctx->framerate.num > 0 && avctx->framerate.den > 0) {
             vseq->num_units_in_tick = avctx->framerate.num;
             vseq->time_scale        = 2 * avctx->framerate.den;
         } else {
             vseq->num_units_in_tick = avctx->time_base.num;
             vseq->time_scale        = 2 * avctx->time_base.den;
         }
 
         vseq->intra_period     = ctx->p_per_i * (ctx->b_per_p + 1);
         vseq->intra_idr_period = vseq->intra_period;
         vseq->ip_period        = ctx->b_per_p + 1;

     }
 
     {
         vpic->CurrPic.picture_id = VA_INVALID_ID;
         vpic->CurrPic.flags      = VA_PICTURE_H264_INVALID;
 
         for (i = 0; i < FF_ARRAY_ELEMS(vpic->ReferenceFrames); i++) {
             vpic->ReferenceFrames[i].picture_id = VA_INVALID_ID;
             vpic->ReferenceFrames[i].flags      = VA_PICTURE_H264_INVALID;
         }
 
         vpic->coded_buf = VA_INVALID_ID;
 
         vpic->pic_parameter_set_id = 0;
         vpic->seq_parameter_set_id = 0;
 
         vpic->num_ref_idx_l0_active_minus1 = 0;
         vpic->num_ref_idx_l1_active_minus1 = 0;
 
         vpic->pic_fields.bits.entropy_coding_mode_flag =
             ((avctx->profile & 0xff) != 66);
         vpic->pic_fields.bits.weighted_pred_flag = 0;
         vpic->pic_fields.bits.weighted_bipred_idc = 0;
         vpic->pic_fields.bits.transform_8x8_mode_flag =
             ((avctx->profile & 0xff) >= 100);
 
         vpic->pic_init_qp = priv->fixed_qp_idr;
     }
 
     {
         mseq->profile_idc = avctx->profile & 0xff;
 
         if (avctx->profile & FF_PROFILE_H264_CONSTRAINED)
             mseq->constraint_set1_flag = 1;
         if (avctx->profile & FF_PROFILE_H264_INTRA)
             mseq->constraint_set3_flag = 1;
     }
 
     return 0;
 }
 
 static int vaapi_encode_h264_init_picture_params(AVCodecContext *avctx,
                                                  VAAPIEncodePicture *pic)
 {
     VAAPIEncodeContext                *ctx = avctx->priv_data;
     VAEncSequenceParameterBufferH264 *vseq = ctx->codec_sequence_params;
     VAEncPictureParameterBufferH264  *vpic = pic->codec_picture_params;
     VAAPIEncodeH264Context           *priv = ctx->priv_data;
     int i;
 
     if (pic->type == PICTURE_TYPE_IDR) {
         av_assert0(pic->display_order == pic->encode_order);
         priv->last_idr_frame = pic->display_order;
     } else {
         av_assert0(pic->display_order > priv->last_idr_frame);
     }
 
     vpic->frame_num = (pic->encode_order - priv->last_idr_frame) &
         ((1 << (4 + vseq->seq_fields.bits.log2_max_frame_num_minus4)) - 1);
 
     vpic->CurrPic.picture_id          = pic->recon_surface;
     vpic->CurrPic.frame_idx           = vpic->frame_num;
     vpic->CurrPic.flags               = 0;
     vpic->CurrPic.TopFieldOrderCnt    = pic->display_order;
     vpic->CurrPic.BottomFieldOrderCnt = pic->display_order;
 
     for (i = 0; i < pic->nb_refs; i++) {
         VAAPIEncodePicture *ref = pic->refs[i];
         av_assert0(ref && ref->encode_order >= priv->last_idr_frame);
         vpic->ReferenceFrames[i].picture_id = ref->recon_surface;
         vpic->ReferenceFrames[i].frame_idx =
             ref->encode_order - priv->last_idr_frame;
         vpic->ReferenceFrames[i].flags = VA_PICTURE_H264_SHORT_TERM_REFERENCE;
         vpic->ReferenceFrames[i].TopFieldOrderCnt    = ref->display_order;
         vpic->ReferenceFrames[i].BottomFieldOrderCnt = ref->display_order;
     }
     for (; i < FF_ARRAY_ELEMS(vpic->ReferenceFrames); i++) {
         vpic->ReferenceFrames[i].picture_id = VA_INVALID_ID;
         vpic->ReferenceFrames[i].flags = VA_PICTURE_H264_INVALID;
     }
 
     vpic->coded_buf = pic->output_buffer;
 
     vpic->pic_fields.bits.idr_pic_flag = (pic->type == PICTURE_TYPE_IDR);
     vpic->pic_fields.bits.reference_pic_flag = (pic->type != PICTURE_TYPE_B);
 
     pic->nb_slices = 1;
 
     return 0;
 }
 
 static int vaapi_encode_h264_init_slice_params(AVCodecContext *avctx,
                                                VAAPIEncodePicture *pic,
                                                VAAPIEncodeSlice *slice)
 {
     VAAPIEncodeContext                 *ctx = avctx->priv_data;
     VAEncSequenceParameterBufferH264  *vseq = ctx->codec_sequence_params;
     VAEncPictureParameterBufferH264   *vpic = pic->codec_picture_params;
     VAEncSliceParameterBufferH264   *vslice = slice->codec_slice_params;
     VAAPIEncodeH264Context            *priv = ctx->priv_data;
     VAAPIEncodeH264Slice            *pslice;
     VAAPIEncodeH264MiscSliceParams  *mslice;
     int i;
 
     slice->priv_data = av_mallocz(sizeof(*pslice));
     if (!slice->priv_data)
         return AVERROR(ENOMEM);
     pslice = slice->priv_data;
     mslice = &pslice->misc_slice_params;
 
     if (pic->type == PICTURE_TYPE_IDR)
         mslice->nal_unit_type = NAL_IDR_SLICE;
     else
         mslice->nal_unit_type = NAL_SLICE;
 
     switch (pic->type) {
     case PICTURE_TYPE_IDR:
         vslice->slice_type  = SLICE_TYPE_I;
         mslice->nal_ref_idc = 3;
         break;
     case PICTURE_TYPE_I:
         vslice->slice_type  = SLICE_TYPE_I;
         mslice->nal_ref_idc = 2;
         break;
     case PICTURE_TYPE_P:
         vslice->slice_type  = SLICE_TYPE_P;
         mslice->nal_ref_idc = 1;
         break;
     case PICTURE_TYPE_B:
         vslice->slice_type  = SLICE_TYPE_B;
         mslice->nal_ref_idc = 0;
         break;
     default:
         av_assert0(0 && "invalid picture type");
     }
 
     // Only one slice per frame.
     vslice->macroblock_address = 0;
     vslice->num_macroblocks = priv->mb_width * priv->mb_height;
 
     vslice->macroblock_info = VA_INVALID_ID;
 
     vslice->pic_parameter_set_id = vpic->pic_parameter_set_id;
     vslice->idr_pic_id = priv->idr_pic_count++;
 
     vslice->pic_order_cnt_lsb = pic->display_order &
         ((1 << (4 + vseq->seq_fields.bits.log2_max_pic_order_cnt_lsb_minus4)) - 1);
 
     for (i = 0; i < FF_ARRAY_ELEMS(vslice->RefPicList0); i++) {
         vslice->RefPicList0[i].picture_id = VA_INVALID_ID;
         vslice->RefPicList0[i].flags      = VA_PICTURE_H264_INVALID;
         vslice->RefPicList1[i].picture_id = VA_INVALID_ID;
         vslice->RefPicList1[i].flags      = VA_PICTURE_H264_INVALID;
     }
 
     av_assert0(pic->nb_refs <= 2);
     if (pic->nb_refs >= 1) {

         // Backward reference for P- or B-frame.

         av_assert0(pic->type == PICTURE_TYPE_P ||
                    pic->type == PICTURE_TYPE_B);
 
         vslice->num_ref_idx_l0_active_minus1 = 0;
         vslice->RefPicList0[0] = vpic->ReferenceFrames[0];
     }
     if (pic->nb_refs >= 2) {

         // Forward reference for B-frame.

         av_assert0(pic->type == PICTURE_TYPE_B);
 
         vslice->num_ref_idx_l1_active_minus1 = 0;
         vslice->RefPicList1[0] = vpic->ReferenceFrames[1];
     }
 
     if (pic->type == PICTURE_TYPE_B)
         vslice->slice_qp_delta = priv->fixed_qp_b - vpic->pic_init_qp;
     else if (pic->type == PICTURE_TYPE_P)
         vslice->slice_qp_delta = priv->fixed_qp_p - vpic->pic_init_qp;
     else
         vslice->slice_qp_delta = priv->fixed_qp_idr - vpic->pic_init_qp;
 
     vslice->direct_spatial_mv_pred_flag = 1;
 
     return 0;
 }
 

 static av_cold int vaapi_encode_h264_init_constant_bitrate(AVCodecContext *avctx)
 {
     VAAPIEncodeContext      *ctx = avctx->priv_data;
     VAAPIEncodeH264Context *priv = ctx->priv_data;
     int hrd_buffer_size;
     int hrd_initial_buffer_fullness;
 

     if (avctx->bit_rate > INT32_MAX) {
         av_log(avctx, AV_LOG_ERROR, "Target bitrate of 2^31 bps or "
                "higher is not supported.\n");
         return AVERROR(EINVAL);
     }
 

     if (avctx->rc_buffer_size)
         hrd_buffer_size = avctx->rc_buffer_size;
     else
         hrd_buffer_size = avctx->bit_rate;
     if (avctx->rc_initial_buffer_occupancy)
         hrd_initial_buffer_fullness = avctx->rc_initial_buffer_occupancy;
     else
         hrd_initial_buffer_fullness = hrd_buffer_size * 3 / 4;
 
     priv->rc_params.misc.type = VAEncMiscParameterTypeRateControl;
     priv->rc_params.rc = (VAEncMiscParameterRateControl) {
         .bits_per_second   = avctx->bit_rate,
         .target_percentage = 66,
         .window_size       = 1000,
         .initial_qp        = (avctx->qmax >= 0 ? avctx->qmax : 40),
         .min_qp            = (avctx->qmin >= 0 ? avctx->qmin : 18),
         .basic_unit_size   = 0,
     };
     ctx->global_params[ctx->nb_global_params] =
         &priv->rc_params.misc;
     ctx->global_params_size[ctx->nb_global_params++] =
         sizeof(priv->rc_params);
 
     priv->hrd_params.misc.type = VAEncMiscParameterTypeHRD;
     priv->hrd_params.hrd = (VAEncMiscParameterHRD) {
         .initial_buffer_fullness = hrd_initial_buffer_fullness,
         .buffer_size             = hrd_buffer_size,
     };
     ctx->global_params[ctx->nb_global_params] =
         &priv->hrd_params.misc;
     ctx->global_params_size[ctx->nb_global_params++] =
         sizeof(priv->hrd_params);
 
     // These still need to be  set for pic_init_qp/slice_qp_delta.
     priv->fixed_qp_idr = 26;
     priv->fixed_qp_p   = 26;
     priv->fixed_qp_b   = 26;
 

     av_log(avctx, AV_LOG_DEBUG, "Using constant-bitrate = %"PRId64" bps.\n",

            avctx->bit_rate);
     return 0;
 }
 
 static av_cold int vaapi_encode_h264_init_fixed_qp(AVCodecContext *avctx)
 {
     VAAPIEncodeContext      *ctx = avctx->priv_data;
     VAAPIEncodeH264Context *priv = ctx->priv_data;

     VAAPIEncodeH264Options  *opt = ctx->codec_options;

     priv->fixed_qp_p = opt->qp;

     if (avctx->i_quant_factor > 0.0)
         priv->fixed_qp_idr = (int)((priv->fixed_qp_p * avctx->i_quant_factor +
                                     avctx->i_quant_offset) + 0.5);
     else
         priv->fixed_qp_idr = priv->fixed_qp_p;
     if (avctx->b_quant_factor > 0.0)
         priv->fixed_qp_b = (int)((priv->fixed_qp_p * avctx->b_quant_factor +
                                   avctx->b_quant_offset) + 0.5);
     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);
     return 0;
 }

 
 static av_cold int vaapi_encode_h264_init_internal(AVCodecContext *avctx)
 {

     static const VAConfigAttrib default_config_attributes[] = {
         { .type  = VAConfigAttribRTFormat,
           .value = VA_RT_FORMAT_YUV420 },
         { .type  = VAConfigAttribEncPackedHeaders,
           .value = (VA_ENC_PACKED_HEADER_SEQUENCE |
                     VA_ENC_PACKED_HEADER_SLICE) },
     };
 

     VAAPIEncodeContext      *ctx = avctx->priv_data;
     VAAPIEncodeH264Context *priv = ctx->priv_data;

     VAAPIEncodeH264Options  *opt = ctx->codec_options;

     int i, err;

 
     switch (avctx->profile) {
     case FF_PROFILE_H264_CONSTRAINED_BASELINE:
         ctx->va_profile = VAProfileH264ConstrainedBaseline;
         break;
     case FF_PROFILE_H264_BASELINE:
         ctx->va_profile = VAProfileH264Baseline;
         break;
     case FF_PROFILE_H264_MAIN:
         ctx->va_profile = VAProfileH264Main;
         break;
     case FF_PROFILE_H264_EXTENDED:
         av_log(avctx, AV_LOG_ERROR, "H.264 extended profile "
                "is not supported.\n");
         return AVERROR_PATCHWELCOME;
     case FF_PROFILE_UNKNOWN:
     case FF_PROFILE_H264_HIGH:
         ctx->va_profile = VAProfileH264High;
         break;
     case FF_PROFILE_H264_HIGH_10:
     case FF_PROFILE_H264_HIGH_10_INTRA:
         av_log(avctx, AV_LOG_ERROR, "H.264 10-bit profiles "
                "are not supported.\n");
         return AVERROR_PATCHWELCOME;
     case FF_PROFILE_H264_HIGH_422:
     case FF_PROFILE_H264_HIGH_422_INTRA:
     case FF_PROFILE_H264_HIGH_444:
     case FF_PROFILE_H264_HIGH_444_PREDICTIVE:
     case FF_PROFILE_H264_HIGH_444_INTRA:
     case FF_PROFILE_H264_CAVLC_444:
         av_log(avctx, AV_LOG_ERROR, "H.264 non-4:2:0 profiles "
                "are not supported.\n");
         return AVERROR_PATCHWELCOME;
     default:
         av_log(avctx, AV_LOG_ERROR, "Unknown H.264 profile %d.\n",
                avctx->profile);
         return AVERROR(EINVAL);
     }
     ctx->va_entrypoint = VAEntrypointEncSlice;
 
     ctx->input_width    = avctx->width;
     ctx->input_height   = avctx->height;
     ctx->aligned_width  = FFALIGN(ctx->input_width,  16);
     ctx->aligned_height = FFALIGN(ctx->input_height, 16);
     priv->mb_width      = ctx->aligned_width  / 16;
     priv->mb_height     = ctx->aligned_height / 16;
 

     for (i = 0; i < FF_ARRAY_ELEMS(default_config_attributes); i++) {
         ctx->config_attributes[ctx->nb_config_attributes++] =
             default_config_attributes[i];
     }
 

     if (avctx->bit_rate > 0) {

         ctx->va_rc_mode = VA_RC_CBR;
         err = vaapi_encode_h264_init_constant_bitrate(avctx);
     } else {
         ctx->va_rc_mode = VA_RC_CQP;
         err = vaapi_encode_h264_init_fixed_qp(avctx);

     }

     if (err < 0)
         return err;

     ctx->config_attributes[ctx->nb_config_attributes++] = (VAConfigAttrib) {
         .type  = VAConfigAttribRateControl,
         .value = ctx->va_rc_mode,
     };

     if (opt->quality > 0) {
 #if VA_CHECK_VERSION(0, 36, 0)
         priv->quality_params.misc.type =
             VAEncMiscParameterTypeQualityLevel;
         priv->quality_params.quality.quality_level = opt->quality;
 
         ctx->global_params[ctx->nb_global_params] =
             &priv->quality_params.misc;
         ctx->global_params_size[ctx->nb_global_params++] =
             sizeof(priv->quality_params);
 #else
         av_log(avctx, AV_LOG_WARNING, "The encode quality option is not "
                "supported with this VAAPI version.\n");
 #endif
     }

 
     ctx->nb_recon_frames = 20;
 
     return 0;
 }
 
 static VAAPIEncodeType vaapi_encode_type_h264 = {
     .priv_data_size        = sizeof(VAAPIEncodeH264Context),
 
     .init                  = &vaapi_encode_h264_init_internal,
 
     .sequence_params_size  = sizeof(VAEncSequenceParameterBufferH264),
     .init_sequence_params  = &vaapi_encode_h264_init_sequence_params,
 
     .picture_params_size   = sizeof(VAEncPictureParameterBufferH264),
     .init_picture_params   = &vaapi_encode_h264_init_picture_params,
 
     .slice_params_size     = sizeof(VAEncSliceParameterBufferH264),
     .init_slice_params     = &vaapi_encode_h264_init_slice_params,
 
     .sequence_header_type  = VAEncPackedHeaderSequence,
     .write_sequence_header = &vaapi_encode_h264_write_sequence_header,
 
     .slice_header_type     = VAEncPackedHeaderH264_Slice,
     .write_slice_header    = &vaapi_encode_h264_write_slice_header,
 };
 
 static av_cold int vaapi_encode_h264_init(AVCodecContext *avctx)
 {
     return ff_vaapi_encode_init(avctx, &vaapi_encode_type_h264);
 }
 

 #define OFFSET(x) (offsetof(VAAPIEncodeContext, codec_options_data) + \
                    offsetof(VAAPIEncodeH264Options, x))
 #define FLAGS (AV_OPT_FLAG_VIDEO_PARAM | AV_OPT_FLAG_ENCODING_PARAM)
 static const AVOption vaapi_encode_h264_options[] = {

     { "qp", "Constant QP (for P-frames; scaled by qfactor/qoffset for I/B)",

       OFFSET(qp), AV_OPT_TYPE_INT, { .i64 = 20 }, 0, 52, FLAGS },

     { "quality", "Set encode quality (trades off against speed, higher is faster)",
       OFFSET(quality), AV_OPT_TYPE_INT, { .i64 = 0 }, 0, 2, FLAGS },

     { NULL },
 };
 

 static const AVCodecDefault vaapi_encode_h264_defaults[] = {
     { "profile",        "100" },
     { "level",          "51"  },
     { "b",              "0"   },
     { "bf",             "2"   },
     { "g",              "120" },
     { "i_qfactor",      "1.0" },
     { "i_qoffset",      "0.0" },
     { "b_qfactor",      "1.2" },
     { "b_qoffset",      "0.0" },
     { NULL },
 };
 
 static const AVClass vaapi_encode_h264_class = {
     .class_name = "h264_vaapi",
     .item_name  = av_default_item_name,

     .option     = vaapi_encode_h264_options,

     .version    = LIBAVUTIL_VERSION_INT,
 };
 
 AVCodec ff_h264_vaapi_encoder = {
     .name           = "h264_vaapi",
     .long_name      = NULL_IF_CONFIG_SMALL("H.264/AVC (VAAPI)"),
     .type           = AVMEDIA_TYPE_VIDEO,
     .id             = AV_CODEC_ID_H264,

     .priv_data_size = (sizeof(VAAPIEncodeContext) +
                        sizeof(VAAPIEncodeH264Options)),

     .init           = &vaapi_encode_h264_init,
     .encode2        = &ff_vaapi_encode2,
     .close          = &ff_vaapi_encode_close,
     .priv_class     = &vaapi_encode_h264_class,
     .capabilities   = AV_CODEC_CAP_DELAY,
     .defaults       = vaapi_encode_h264_defaults,
     .pix_fmts = (const enum AVPixelFormat[]) {
         AV_PIX_FMT_VAAPI,
         AV_PIX_FMT_NONE,
     },
 };