/*
  * H.264 HW decode acceleration through VA API
  *
  * Copyright (C) 2008-2009 Splitted-Desktop Systems
  *
  * 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 "vaapi_internal.h"
 #include "h264.h"
 

 /**
  * @file

  * This file implements the glue code between FFmpeg's and VA API's

  * structures for H.264 decoding.

  */
 
 /**

  * Initialize an empty VA API picture.

  *
  * VA API requires a fixed-size reference picture array.
  */
 static void init_vaapi_pic(VAPictureH264 *va_pic)
 {
     va_pic->picture_id          = VA_INVALID_ID;
     va_pic->flags               = VA_PICTURE_H264_INVALID;
     va_pic->TopFieldOrderCnt    = 0;
     va_pic->BottomFieldOrderCnt = 0;
 }
 
 /**

  * Translate an FFmpeg Picture into its VA API form.

  *
  * @param[out] va_pic          A pointer to VA API's own picture struct
  * @param[in]  pic             A pointer to the FFmpeg picture struct to convert
  * @param[in]  pic_structure   The picture field type (as defined in mpegvideo.h),
  *                             supersedes pic's field type if nonzero.
  */
 static void fill_vaapi_pic(VAPictureH264 *va_pic,
                            Picture       *pic,
                            int            pic_structure)
 {
     if (pic_structure == 0)

         pic_structure = pic->reference;

     pic_structure &= PICT_FRAME; /* PICT_TOP_FIELD|PICT_BOTTOM_FIELD */

 
     va_pic->picture_id = ff_vaapi_get_surface_id(pic);
     va_pic->frame_idx  = pic->long_ref ? pic->pic_id : pic->frame_num;
 
     va_pic->flags      = 0;
     if (pic_structure != PICT_FRAME)
         va_pic->flags |= (pic_structure & PICT_TOP_FIELD) ? VA_PICTURE_H264_TOP_FIELD : VA_PICTURE_H264_BOTTOM_FIELD;

     if (pic->reference)

         va_pic->flags |= pic->long_ref ? VA_PICTURE_H264_LONG_TERM_REFERENCE : VA_PICTURE_H264_SHORT_TERM_REFERENCE;
 
     va_pic->TopFieldOrderCnt = 0;
     if (pic->field_poc[0] != INT_MAX)
         va_pic->TopFieldOrderCnt = pic->field_poc[0];
 
     va_pic->BottomFieldOrderCnt = 0;
     if (pic->field_poc[1] != INT_MAX)
         va_pic->BottomFieldOrderCnt = pic->field_poc[1];
 }
 
 /** Decoded Picture Buffer (DPB). */
 typedef struct DPB {
     int            size;        ///< Current number of reference frames in the DPB
     int            max_size;    ///< Max number of reference frames. This is FF_ARRAY_ELEMS(VAPictureParameterBufferH264.ReferenceFrames)
     VAPictureH264 *va_pics;     ///< Pointer to VAPictureParameterBufferH264.ReferenceFrames array
 } DPB;
 
 /**

  * Append picture to the decoded picture buffer, in a VA API form that

  * merges the second field picture attributes with the first, if
  * available.  The decoded picture buffer's size must be large enough
  * to receive the new VA API picture object.
  */
 static int dpb_add(DPB *dpb, Picture *pic)
 {
     int i;
 
     if (dpb->size >= dpb->max_size)
         return -1;
 
     for (i = 0; i < dpb->size; i++) {
         VAPictureH264 * const va_pic = &dpb->va_pics[i];
         if (va_pic->picture_id == ff_vaapi_get_surface_id(pic)) {
             VAPictureH264 temp_va_pic;
             fill_vaapi_pic(&temp_va_pic, pic, 0);
 
             if ((temp_va_pic.flags ^ va_pic->flags) & (VA_PICTURE_H264_TOP_FIELD | VA_PICTURE_H264_BOTTOM_FIELD)) {
                 va_pic->flags |= temp_va_pic.flags & (VA_PICTURE_H264_TOP_FIELD | VA_PICTURE_H264_BOTTOM_FIELD);
                 /* Merge second field */
                 if (temp_va_pic.flags & VA_PICTURE_H264_TOP_FIELD) {
                     va_pic->TopFieldOrderCnt    = temp_va_pic.TopFieldOrderCnt;
                 } else {
                     va_pic->BottomFieldOrderCnt = temp_va_pic.BottomFieldOrderCnt;
                 }
             }
             return 0;
         }
     }
 
     fill_vaapi_pic(&dpb->va_pics[dpb->size++], pic, 0);
     return 0;
 }
 

 /** Fill in VA API reference frames array. */

 static int fill_vaapi_ReferenceFrames(VAPictureParameterBufferH264 *pic_param,
                                       H264Context                  *h)
 {
     DPB dpb;
     int i;
 
     dpb.size     = 0;
     dpb.max_size = FF_ARRAY_ELEMS(pic_param->ReferenceFrames);
     dpb.va_pics  = pic_param->ReferenceFrames;
     for (i = 0; i < dpb.max_size; i++)
         init_vaapi_pic(&dpb.va_pics[i]);
 
     for (i = 0; i < h->short_ref_count; i++) {
         Picture * const pic = h->short_ref[i];

         if (pic && pic->reference && dpb_add(&dpb, pic) < 0)

             return -1;
     }
 

     for (i = 0; i < 16; i++) {

         Picture * const pic = h->long_ref[i];

         if (pic && pic->reference && dpb_add(&dpb, pic) < 0)

             return -1;
     }
     return 0;
 }
 
 /**

  * Fill in VA API reference picture lists from the FFmpeg reference

  * picture list.
  *
  * @param[out] RefPicList  VA API internal reference picture list
  * @param[in]  ref_list    A pointer to the FFmpeg reference list
  * @param[in]  ref_count   The number of reference pictures in ref_list
  */
 static void fill_vaapi_RefPicList(VAPictureH264 RefPicList[32],
                                   Picture      *ref_list,
                                   unsigned int  ref_count)
 {
     unsigned int i, n = 0;
     for (i = 0; i < ref_count; i++)

         if (ref_list[i].reference)

             fill_vaapi_pic(&RefPicList[n++], &ref_list[i], 0);
 
     for (; n < 32; n++)
         init_vaapi_pic(&RefPicList[n]);
 }
 
 /**

  * Fill in prediction weight table.

  *
  * VA API requires a plain prediction weight table as it does not infer
  * any value.
  *
  * @param[in]  h                   A pointer to the current H.264 context
  * @param[in]  list                The reference frame list index to use
  * @param[out] luma_weight_flag    VA API plain luma weight flag
  * @param[out] luma_weight         VA API plain luma weight table
  * @param[out] luma_offset         VA API plain luma offset table
  * @param[out] chroma_weight_flag  VA API plain chroma weight flag
  * @param[out] chroma_weight       VA API plain chroma weight table
  * @param[out] chroma_offset       VA API plain chroma offset table
  */
 static void fill_vaapi_plain_pred_weight_table(H264Context   *h,
                                                int            list,
                                                unsigned char *luma_weight_flag,
                                                short          luma_weight[32],
                                                short          luma_offset[32],
                                                unsigned char *chroma_weight_flag,
                                                short          chroma_weight[32][2],
                                                short          chroma_offset[32][2])
 {
     unsigned int i, j;
 
     *luma_weight_flag    = h->luma_weight_flag[list];
     *chroma_weight_flag  = h->chroma_weight_flag[list];
 
     for (i = 0; i < h->ref_count[list]; i++) {
         /* VA API also wants the inferred (default) values, not
            only what is available in the bitstream (7.4.3.2). */
         if (h->luma_weight_flag[list]) {

             luma_weight[i] = h->luma_weight[i][list][0];
             luma_offset[i] = h->luma_weight[i][list][1];

         } else {
             luma_weight[i] = 1 << h->luma_log2_weight_denom;
             luma_offset[i] = 0;
         }
         for (j = 0; j < 2; j++) {
             if (h->chroma_weight_flag[list]) {

                 chroma_weight[i][j] = h->chroma_weight[i][list][j][0];
                 chroma_offset[i][j] = h->chroma_weight[i][list][j][1];

             } else {
                 chroma_weight[i][j] = 1 << h->chroma_log2_weight_denom;
                 chroma_offset[i][j] = 0;
             }
         }
     }
 }
 

 /** Initialize and start decoding a frame with VA API. */

 static int vaapi_h264_start_frame(AVCodecContext          *avctx,
                                   av_unused const uint8_t *buffer,
                                   av_unused uint32_t       size)

 {
     H264Context * const h = avctx->priv_data;
     struct vaapi_context * const vactx = avctx->hwaccel_context;
     VAPictureParameterBufferH264 *pic_param;
     VAIQMatrixBufferH264 *iq_matrix;
 

     av_dlog(avctx, "vaapi_h264_start_frame()\n");

 
     vactx->slice_param_size = sizeof(VASliceParameterBufferH264);
 
     /* Fill in VAPictureParameterBufferH264. */
     pic_param = ff_vaapi_alloc_pic_param(vactx, sizeof(VAPictureParameterBufferH264));
     if (!pic_param)
         return -1;

     fill_vaapi_pic(&pic_param->CurrPic, h->cur_pic_ptr, h->picture_structure);

     if (fill_vaapi_ReferenceFrames(pic_param, h) < 0)
         return -1;

     pic_param->picture_width_in_mbs_minus1                      = h->mb_width - 1;
     pic_param->picture_height_in_mbs_minus1                     = h->mb_height - 1;

     pic_param->bit_depth_luma_minus8                            = h->sps.bit_depth_luma - 8;
     pic_param->bit_depth_chroma_minus8                          = h->sps.bit_depth_chroma - 8;
     pic_param->num_ref_frames                                   = h->sps.ref_frame_count;
     pic_param->seq_fields.value                                 = 0; /* reset all bits */
     pic_param->seq_fields.bits.chroma_format_idc                = h->sps.chroma_format_idc;
     pic_param->seq_fields.bits.residual_colour_transform_flag   = h->sps.residual_color_transform_flag; /* XXX: only for 4:4:4 high profile? */
     pic_param->seq_fields.bits.gaps_in_frame_num_value_allowed_flag = h->sps.gaps_in_frame_num_allowed_flag;
     pic_param->seq_fields.bits.frame_mbs_only_flag              = h->sps.frame_mbs_only_flag;
     pic_param->seq_fields.bits.mb_adaptive_frame_field_flag     = h->sps.mb_aff;
     pic_param->seq_fields.bits.direct_8x8_inference_flag        = h->sps.direct_8x8_inference_flag;
     pic_param->seq_fields.bits.MinLumaBiPredSize8x8             = h->sps.level_idc >= 31; /* A.3.3.2 */
     pic_param->seq_fields.bits.log2_max_frame_num_minus4        = h->sps.log2_max_frame_num - 4;
     pic_param->seq_fields.bits.pic_order_cnt_type               = h->sps.poc_type;
     pic_param->seq_fields.bits.log2_max_pic_order_cnt_lsb_minus4 = h->sps.log2_max_poc_lsb - 4;
     pic_param->seq_fields.bits.delta_pic_order_always_zero_flag = h->sps.delta_pic_order_always_zero_flag;
     pic_param->num_slice_groups_minus1                          = h->pps.slice_group_count - 1;
     pic_param->slice_group_map_type                             = h->pps.mb_slice_group_map_type;

     pic_param->slice_group_change_rate_minus1                   = 0; /* XXX: unimplemented in FFmpeg */

     pic_param->pic_init_qp_minus26                              = h->pps.init_qp - 26;
     pic_param->pic_init_qs_minus26                              = h->pps.init_qs - 26;
     pic_param->chroma_qp_index_offset                           = h->pps.chroma_qp_index_offset[0];
     pic_param->second_chroma_qp_index_offset                    = h->pps.chroma_qp_index_offset[1];
     pic_param->pic_fields.value                                 = 0; /* reset all bits */
     pic_param->pic_fields.bits.entropy_coding_mode_flag         = h->pps.cabac;
     pic_param->pic_fields.bits.weighted_pred_flag               = h->pps.weighted_pred;
     pic_param->pic_fields.bits.weighted_bipred_idc              = h->pps.weighted_bipred_idc;
     pic_param->pic_fields.bits.transform_8x8_mode_flag          = h->pps.transform_8x8_mode;

     pic_param->pic_fields.bits.field_pic_flag                   = h->picture_structure != PICT_FRAME;

     pic_param->pic_fields.bits.constrained_intra_pred_flag      = h->pps.constrained_intra_pred;
     pic_param->pic_fields.bits.pic_order_present_flag           = h->pps.pic_order_present;
     pic_param->pic_fields.bits.deblocking_filter_control_present_flag = h->pps.deblocking_filter_parameters_present;
     pic_param->pic_fields.bits.redundant_pic_cnt_present_flag   = h->pps.redundant_pic_cnt_present;
     pic_param->pic_fields.bits.reference_pic_flag               = h->nal_ref_idc != 0;
     pic_param->frame_num                                        = h->frame_num;
 
     /* Fill in VAIQMatrixBufferH264. */
     iq_matrix = ff_vaapi_alloc_iq_matrix(vactx, sizeof(VAIQMatrixBufferH264));
     if (!iq_matrix)
         return -1;
     memcpy(iq_matrix->ScalingList4x4, h->pps.scaling_matrix4, sizeof(iq_matrix->ScalingList4x4));

     memcpy(iq_matrix->ScalingList8x8[0], h->pps.scaling_matrix8[0], sizeof(iq_matrix->ScalingList8x8[0]));
     memcpy(iq_matrix->ScalingList8x8[1], h->pps.scaling_matrix8[3], sizeof(iq_matrix->ScalingList8x8[0]));

     return 0;
 }
 

 /** End a hardware decoding based frame. */

 static int vaapi_h264_end_frame(AVCodecContext *avctx)

 {

     struct vaapi_context * const vactx = avctx->hwaccel_context;

     H264Context * const h = avctx->priv_data;

     int ret;

     av_dlog(avctx, "vaapi_h264_end_frame()\n");

     ret = ff_vaapi_commit_slices(vactx);
     if (ret < 0)
         goto finish;
 
     ret = ff_vaapi_render_picture(vactx, ff_vaapi_get_surface_id(h->cur_pic_ptr));
     if (ret < 0)
         goto finish;
 
     ff_h264_draw_horiz_band(h, 0, h->avctx->height);
 
 finish:
     ff_vaapi_common_end_frame(avctx);
     return ret;

 }
 

 /** Decode the given H.264 slice with VA API. */

 static int vaapi_h264_decode_slice(AVCodecContext *avctx,
                                    const uint8_t  *buffer,
                                    uint32_t        size)

 {
     H264Context * const h = avctx->priv_data;
     VASliceParameterBufferH264 *slice_param;
 

     av_dlog(avctx, "vaapi_h264_decode_slice(): buffer %p, size %d\n",
             buffer, size);

 
     /* Fill in VASliceParameterBufferH264. */
     slice_param = (VASliceParameterBufferH264 *)ff_vaapi_alloc_slice(avctx->hwaccel_context, buffer, size);
     if (!slice_param)
         return -1;

     slice_param->slice_data_bit_offset          = get_bits_count(&h->gb) + 8; /* bit buffer started beyond nal_unit_type */

     slice_param->first_mb_in_slice              = (h->mb_y >> FIELD_OR_MBAFF_PICTURE(h)) * h->mb_width + h->mb_x;

     slice_param->slice_type                     = ff_h264_get_slice_type(h);

     slice_param->direct_spatial_mv_pred_flag    = h->slice_type == AV_PICTURE_TYPE_B ? h->direct_spatial_mv_pred : 0;

     slice_param->num_ref_idx_l0_active_minus1   = h->list_count > 0 ? h->ref_count[0] - 1 : 0;
     slice_param->num_ref_idx_l1_active_minus1   = h->list_count > 1 ? h->ref_count[1] - 1 : 0;
     slice_param->cabac_init_idc                 = h->cabac_init_idc;

     slice_param->slice_qp_delta                 = h->qscale - h->pps.init_qp;

     slice_param->disable_deblocking_filter_idc  = h->deblocking_filter < 2 ? !h->deblocking_filter : h->deblocking_filter;

     slice_param->slice_alpha_c0_offset_div2     = h->slice_alpha_c0_offset / 2;
     slice_param->slice_beta_offset_div2         = h->slice_beta_offset     / 2;

     slice_param->luma_log2_weight_denom         = h->luma_log2_weight_denom;
     slice_param->chroma_log2_weight_denom       = h->chroma_log2_weight_denom;
 
     fill_vaapi_RefPicList(slice_param->RefPicList0, h->ref_list[0], h->list_count > 0 ? h->ref_count[0] : 0);
     fill_vaapi_RefPicList(slice_param->RefPicList1, h->ref_list[1], h->list_count > 1 ? h->ref_count[1] : 0);
 
     fill_vaapi_plain_pred_weight_table(h, 0,
                                        &slice_param->luma_weight_l0_flag,   slice_param->luma_weight_l0,   slice_param->luma_offset_l0,
                                        &slice_param->chroma_weight_l0_flag, slice_param->chroma_weight_l0, slice_param->chroma_offset_l0);
     fill_vaapi_plain_pred_weight_table(h, 1,
                                        &slice_param->luma_weight_l1_flag,   slice_param->luma_weight_l1,   slice_param->luma_offset_l1,
                                        &slice_param->chroma_weight_l1_flag, slice_param->chroma_weight_l1, slice_param->chroma_offset_l1);
     return 0;
 }
 

 AVHWAccel ff_h264_vaapi_hwaccel = {

     .name           = "h264_vaapi",

     .type           = AVMEDIA_TYPE_VIDEO,

     .id             = AV_CODEC_ID_H264,

     .pix_fmt        = AV_PIX_FMT_VAAPI_VLD,

     .start_frame    = vaapi_h264_start_frame,
     .end_frame      = vaapi_h264_end_frame,
     .decode_slice   = vaapi_h264_decode_slice,

 };