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vaapi_h264.c
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1 /*
2  * H.264 HW decode acceleration through VA API
3  *
4  * Copyright (C) 2008-2009 Splitted-Desktop Systems
5  *
6  * This file is part of FFmpeg.
7  *
8  * FFmpeg is free software; you can redistribute it and/or
9  * modify it under the terms of the GNU Lesser General Public
10  * License as published by the Free Software Foundation; either
11  * version 2.1 of the License, or (at your option) any later version.
12  *
13  * FFmpeg is distributed in the hope that it will be useful,
14  * but WITHOUT ANY WARRANTY; without even the implied warranty of
15  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
16  * Lesser General Public License for more details.
17  *
18  * You should have received a copy of the GNU Lesser General Public
19  * License along with FFmpeg; if not, write to the Free Software
20  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
21  */
22 
23 #include "vaapi_internal.h"
24 #include "h264.h"
25 
26 /**
27  * @file
28  * This file implements the glue code between FFmpeg's and VA API's
29  * structures for H.264 decoding.
30  */
31 
32 /**
33  * Initialize an empty VA API picture.
34  *
35  * VA API requires a fixed-size reference picture array.
36  */
37 static void init_vaapi_pic(VAPictureH264 *va_pic)
38 {
39  va_pic->picture_id = VA_INVALID_ID;
40  va_pic->flags = VA_PICTURE_H264_INVALID;
41  va_pic->TopFieldOrderCnt = 0;
42  va_pic->BottomFieldOrderCnt = 0;
43 }
44 
45 /**
46  * Translate an FFmpeg Picture into its VA API form.
47  *
48  * @param[out] va_pic A pointer to VA API's own picture struct
49  * @param[in] pic A pointer to the FFmpeg picture struct to convert
50  * @param[in] pic_structure The picture field type (as defined in mpegvideo.h),
51  * supersedes pic's field type if nonzero.
52  */
53 static void fill_vaapi_pic(VAPictureH264 *va_pic,
54  Picture *pic,
55  int pic_structure)
56 {
57  if (pic_structure == 0)
58  pic_structure = pic->f.reference;
59  pic_structure &= PICT_FRAME; /* PICT_TOP_FIELD|PICT_BOTTOM_FIELD */
60 
61  va_pic->picture_id = ff_vaapi_get_surface_id(pic);
62  va_pic->frame_idx = pic->long_ref ? pic->pic_id : pic->frame_num;
63 
64  va_pic->flags = 0;
65  if (pic_structure != PICT_FRAME)
66  va_pic->flags |= (pic_structure & PICT_TOP_FIELD) ? VA_PICTURE_H264_TOP_FIELD : VA_PICTURE_H264_BOTTOM_FIELD;
67  if (pic->f.reference)
68  va_pic->flags |= pic->long_ref ? VA_PICTURE_H264_LONG_TERM_REFERENCE : VA_PICTURE_H264_SHORT_TERM_REFERENCE;
69 
70  va_pic->TopFieldOrderCnt = 0;
71  if (pic->field_poc[0] != INT_MAX)
72  va_pic->TopFieldOrderCnt = pic->field_poc[0];
73 
74  va_pic->BottomFieldOrderCnt = 0;
75  if (pic->field_poc[1] != INT_MAX)
76  va_pic->BottomFieldOrderCnt = pic->field_poc[1];
77 }
78 
79 /** Decoded Picture Buffer (DPB). */
80 typedef struct DPB {
81  int size; ///< Current number of reference frames in the DPB
82  int max_size; ///< Max number of reference frames. This is FF_ARRAY_ELEMS(VAPictureParameterBufferH264.ReferenceFrames)
83  VAPictureH264 *va_pics; ///< Pointer to VAPictureParameterBufferH264.ReferenceFrames array
84 } DPB;
85 
86 /**
87  * Append picture to the decoded picture buffer, in a VA API form that
88  * merges the second field picture attributes with the first, if
89  * available. The decoded picture buffer's size must be large enough
90  * to receive the new VA API picture object.
91  */
92 static int dpb_add(DPB *dpb, Picture *pic)
93 {
94  int i;
95 
96  if (dpb->size >= dpb->max_size)
97  return -1;
98 
99  for (i = 0; i < dpb->size; i++) {
100  VAPictureH264 * const va_pic = &dpb->va_pics[i];
101  if (va_pic->picture_id == ff_vaapi_get_surface_id(pic)) {
102  VAPictureH264 temp_va_pic;
103  fill_vaapi_pic(&temp_va_pic, pic, 0);
104 
105  if ((temp_va_pic.flags ^ va_pic->flags) & (VA_PICTURE_H264_TOP_FIELD | VA_PICTURE_H264_BOTTOM_FIELD)) {
106  va_pic->flags |= temp_va_pic.flags & (VA_PICTURE_H264_TOP_FIELD | VA_PICTURE_H264_BOTTOM_FIELD);
107  /* Merge second field */
108  if (temp_va_pic.flags & VA_PICTURE_H264_TOP_FIELD) {
109  va_pic->TopFieldOrderCnt = temp_va_pic.TopFieldOrderCnt;
110  } else {
111  va_pic->BottomFieldOrderCnt = temp_va_pic.BottomFieldOrderCnt;
112  }
113  }
114  return 0;
115  }
116  }
117 
118  fill_vaapi_pic(&dpb->va_pics[dpb->size++], pic, 0);
119  return 0;
120 }
121 
122 /** Fill in VA API reference frames array. */
123 static int fill_vaapi_ReferenceFrames(VAPictureParameterBufferH264 *pic_param,
124  H264Context *h)
125 {
126  DPB dpb;
127  int i;
128 
129  dpb.size = 0;
130  dpb.max_size = FF_ARRAY_ELEMS(pic_param->ReferenceFrames);
131  dpb.va_pics = pic_param->ReferenceFrames;
132  for (i = 0; i < dpb.max_size; i++)
133  init_vaapi_pic(&dpb.va_pics[i]);
134 
135  for (i = 0; i < h->short_ref_count; i++) {
136  Picture * const pic = h->short_ref[i];
137  if (pic && pic->f.reference && dpb_add(&dpb, pic) < 0)
138  return -1;
139  }
140 
141  for (i = 0; i < 16; i++) {
142  Picture * const pic = h->long_ref[i];
143  if (pic && pic->f.reference && dpb_add(&dpb, pic) < 0)
144  return -1;
145  }
146  return 0;
147 }
148 
149 /**
150  * Fill in VA API reference picture lists from the FFmpeg reference
151  * picture list.
152  *
153  * @param[out] RefPicList VA API internal reference picture list
154  * @param[in] ref_list A pointer to the FFmpeg reference list
155  * @param[in] ref_count The number of reference pictures in ref_list
156  */
157 static void fill_vaapi_RefPicList(VAPictureH264 RefPicList[32],
158  Picture *ref_list,
159  unsigned int ref_count)
160 {
161  unsigned int i, n = 0;
162  for (i = 0; i < ref_count; i++)
163  if (ref_list[i].f.reference)
164  fill_vaapi_pic(&RefPicList[n++], &ref_list[i], 0);
165 
166  for (; n < 32; n++)
167  init_vaapi_pic(&RefPicList[n]);
168 }
169 
170 /**
171  * Fill in prediction weight table.
172  *
173  * VA API requires a plain prediction weight table as it does not infer
174  * any value.
175  *
176  * @param[in] h A pointer to the current H.264 context
177  * @param[in] list The reference frame list index to use
178  * @param[out] luma_weight_flag VA API plain luma weight flag
179  * @param[out] luma_weight VA API plain luma weight table
180  * @param[out] luma_offset VA API plain luma offset table
181  * @param[out] chroma_weight_flag VA API plain chroma weight flag
182  * @param[out] chroma_weight VA API plain chroma weight table
183  * @param[out] chroma_offset VA API plain chroma offset table
184  */
186  int list,
187  unsigned char *luma_weight_flag,
188  short luma_weight[32],
189  short luma_offset[32],
190  unsigned char *chroma_weight_flag,
191  short chroma_weight[32][2],
192  short chroma_offset[32][2])
193 {
194  unsigned int i, j;
195 
196  *luma_weight_flag = h->luma_weight_flag[list];
197  *chroma_weight_flag = h->chroma_weight_flag[list];
198 
199  for (i = 0; i < h->ref_count[list]; i++) {
200  /* VA API also wants the inferred (default) values, not
201  only what is available in the bitstream (7.4.3.2). */
202  if (h->luma_weight_flag[list]) {
203  luma_weight[i] = h->luma_weight[i][list][0];
204  luma_offset[i] = h->luma_weight[i][list][1];
205  } else {
206  luma_weight[i] = 1 << h->luma_log2_weight_denom;
207  luma_offset[i] = 0;
208  }
209  for (j = 0; j < 2; j++) {
210  if (h->chroma_weight_flag[list]) {
211  chroma_weight[i][j] = h->chroma_weight[i][list][j][0];
212  chroma_offset[i][j] = h->chroma_weight[i][list][j][1];
213  } else {
214  chroma_weight[i][j] = 1 << h->chroma_log2_weight_denom;
215  chroma_offset[i][j] = 0;
216  }
217  }
218  }
219 }
220 
221 /** Initialize and start decoding a frame with VA API. */
223  av_unused const uint8_t *buffer,
224  av_unused uint32_t size)
225 {
226  H264Context * const h = avctx->priv_data;
227  struct vaapi_context * const vactx = avctx->hwaccel_context;
228  VAPictureParameterBufferH264 *pic_param;
229  VAIQMatrixBufferH264 *iq_matrix;
230 
231  av_dlog(avctx, "vaapi_h264_start_frame()\n");
232 
233  vactx->slice_param_size = sizeof(VASliceParameterBufferH264);
234 
235  /* Fill in VAPictureParameterBufferH264. */
236  pic_param = ff_vaapi_alloc_pic_param(vactx, sizeof(VAPictureParameterBufferH264));
237  if (!pic_param)
238  return -1;
239  fill_vaapi_pic(&pic_param->CurrPic, h->cur_pic_ptr, h->picture_structure);
240  if (fill_vaapi_ReferenceFrames(pic_param, h) < 0)
241  return -1;
242  pic_param->picture_width_in_mbs_minus1 = h->mb_width - 1;
243  pic_param->picture_height_in_mbs_minus1 = h->mb_height - 1;
244  pic_param->bit_depth_luma_minus8 = h->sps.bit_depth_luma - 8;
245  pic_param->bit_depth_chroma_minus8 = h->sps.bit_depth_chroma - 8;
246  pic_param->num_ref_frames = h->sps.ref_frame_count;
247  pic_param->seq_fields.value = 0; /* reset all bits */
248  pic_param->seq_fields.bits.chroma_format_idc = h->sps.chroma_format_idc;
249  pic_param->seq_fields.bits.residual_colour_transform_flag = h->sps.residual_color_transform_flag; /* XXX: only for 4:4:4 high profile? */
250  pic_param->seq_fields.bits.gaps_in_frame_num_value_allowed_flag = h->sps.gaps_in_frame_num_allowed_flag;
251  pic_param->seq_fields.bits.frame_mbs_only_flag = h->sps.frame_mbs_only_flag;
252  pic_param->seq_fields.bits.mb_adaptive_frame_field_flag = h->sps.mb_aff;
253  pic_param->seq_fields.bits.direct_8x8_inference_flag = h->sps.direct_8x8_inference_flag;
254  pic_param->seq_fields.bits.MinLumaBiPredSize8x8 = h->sps.level_idc >= 31; /* A.3.3.2 */
255  pic_param->seq_fields.bits.log2_max_frame_num_minus4 = h->sps.log2_max_frame_num - 4;
256  pic_param->seq_fields.bits.pic_order_cnt_type = h->sps.poc_type;
257  pic_param->seq_fields.bits.log2_max_pic_order_cnt_lsb_minus4 = h->sps.log2_max_poc_lsb - 4;
258  pic_param->seq_fields.bits.delta_pic_order_always_zero_flag = h->sps.delta_pic_order_always_zero_flag;
259  pic_param->num_slice_groups_minus1 = h->pps.slice_group_count - 1;
260  pic_param->slice_group_map_type = h->pps.mb_slice_group_map_type;
261  pic_param->slice_group_change_rate_minus1 = 0; /* XXX: unimplemented in FFmpeg */
262  pic_param->pic_init_qp_minus26 = h->pps.init_qp - 26;
263  pic_param->pic_init_qs_minus26 = h->pps.init_qs - 26;
264  pic_param->chroma_qp_index_offset = h->pps.chroma_qp_index_offset[0];
265  pic_param->second_chroma_qp_index_offset = h->pps.chroma_qp_index_offset[1];
266  pic_param->pic_fields.value = 0; /* reset all bits */
267  pic_param->pic_fields.bits.entropy_coding_mode_flag = h->pps.cabac;
268  pic_param->pic_fields.bits.weighted_pred_flag = h->pps.weighted_pred;
269  pic_param->pic_fields.bits.weighted_bipred_idc = h->pps.weighted_bipred_idc;
270  pic_param->pic_fields.bits.transform_8x8_mode_flag = h->pps.transform_8x8_mode;
271  pic_param->pic_fields.bits.field_pic_flag = h->picture_structure != PICT_FRAME;
272  pic_param->pic_fields.bits.constrained_intra_pred_flag = h->pps.constrained_intra_pred;
273  pic_param->pic_fields.bits.pic_order_present_flag = h->pps.pic_order_present;
274  pic_param->pic_fields.bits.deblocking_filter_control_present_flag = h->pps.deblocking_filter_parameters_present;
275  pic_param->pic_fields.bits.redundant_pic_cnt_present_flag = h->pps.redundant_pic_cnt_present;
276  pic_param->pic_fields.bits.reference_pic_flag = h->nal_ref_idc != 0;
277  pic_param->frame_num = h->frame_num;
278 
279  /* Fill in VAIQMatrixBufferH264. */
280  iq_matrix = ff_vaapi_alloc_iq_matrix(vactx, sizeof(VAIQMatrixBufferH264));
281  if (!iq_matrix)
282  return -1;
283  memcpy(iq_matrix->ScalingList4x4, h->pps.scaling_matrix4, sizeof(iq_matrix->ScalingList4x4));
284  memcpy(iq_matrix->ScalingList8x8[0], h->pps.scaling_matrix8[0], sizeof(iq_matrix->ScalingList8x8[0]));
285  memcpy(iq_matrix->ScalingList8x8[1], h->pps.scaling_matrix8[3], sizeof(iq_matrix->ScalingList8x8[0]));
286  return 0;
287 }
288 
289 /** End a hardware decoding based frame. */
291 {
292  struct vaapi_context * const vactx = avctx->hwaccel_context;
293  H264Context * const h = avctx->priv_data;
294  int ret;
295 
296  av_dlog(avctx, "vaapi_h264_end_frame()\n");
297  ret = ff_vaapi_commit_slices(vactx);
298  if (ret < 0)
299  goto finish;
300 
302  if (ret < 0)
303  goto finish;
304 
306 
307 finish:
309  return ret;
310 }
311 
312 /** Decode the given H.264 slice with VA API. */
314  const uint8_t *buffer,
315  uint32_t size)
316 {
317  H264Context * const h = avctx->priv_data;
318  VASliceParameterBufferH264 *slice_param;
319 
320  av_dlog(avctx, "vaapi_h264_decode_slice(): buffer %p, size %d\n",
321  buffer, size);
322 
323  /* Fill in VASliceParameterBufferH264. */
324  slice_param = (VASliceParameterBufferH264 *)ff_vaapi_alloc_slice(avctx->hwaccel_context, buffer, size);
325  if (!slice_param)
326  return -1;
327  slice_param->slice_data_bit_offset = get_bits_count(&h->gb) + 8; /* bit buffer started beyond nal_unit_type */
328  slice_param->first_mb_in_slice = (h->mb_y >> FIELD_OR_MBAFF_PICTURE) * h->mb_width + h->mb_x;
329  slice_param->slice_type = ff_h264_get_slice_type(h);
330  slice_param->direct_spatial_mv_pred_flag = h->slice_type == AV_PICTURE_TYPE_B ? h->direct_spatial_mv_pred : 0;
331  slice_param->num_ref_idx_l0_active_minus1 = h->list_count > 0 ? h->ref_count[0] - 1 : 0;
332  slice_param->num_ref_idx_l1_active_minus1 = h->list_count > 1 ? h->ref_count[1] - 1 : 0;
333  slice_param->cabac_init_idc = h->cabac_init_idc;
334  slice_param->slice_qp_delta = h->qscale - h->pps.init_qp;
335  slice_param->disable_deblocking_filter_idc = h->deblocking_filter < 2 ? !h->deblocking_filter : h->deblocking_filter;
336  slice_param->slice_alpha_c0_offset_div2 = h->slice_alpha_c0_offset / 2 - 26;
337  slice_param->slice_beta_offset_div2 = h->slice_beta_offset / 2 - 26;
338  slice_param->luma_log2_weight_denom = h->luma_log2_weight_denom;
339  slice_param->chroma_log2_weight_denom = h->chroma_log2_weight_denom;
340 
341  fill_vaapi_RefPicList(slice_param->RefPicList0, h->ref_list[0], h->list_count > 0 ? h->ref_count[0] : 0);
342  fill_vaapi_RefPicList(slice_param->RefPicList1, h->ref_list[1], h->list_count > 1 ? h->ref_count[1] : 0);
343 
345  &slice_param->luma_weight_l0_flag, slice_param->luma_weight_l0, slice_param->luma_offset_l0,
346  &slice_param->chroma_weight_l0_flag, slice_param->chroma_weight_l0, slice_param->chroma_offset_l0);
348  &slice_param->luma_weight_l1_flag, slice_param->luma_weight_l1, slice_param->luma_offset_l1,
349  &slice_param->chroma_weight_l1_flag, slice_param->chroma_weight_l1, slice_param->chroma_offset_l1);
350  return 0;
351 }
352 
354  .name = "h264_vaapi",
355  .type = AVMEDIA_TYPE_VIDEO,
356  .id = AV_CODEC_ID_H264,
357  .pix_fmt = AV_PIX_FMT_VAAPI_VLD,
358  .start_frame = vaapi_h264_start_frame,
359  .end_frame = vaapi_h264_end_frame,
360  .decode_slice = vaapi_h264_decode_slice,
361 };