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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 #include "mpegutils.h"
26 
27 /**
28  * @file
29  * This file implements the glue code between FFmpeg's and VA API's
30  * structures for H.264 decoding.
31  */
32 
33 /**
34  * Initialize an empty VA API picture.
35  *
36  * VA API requires a fixed-size reference picture array.
37  */
38 static void init_vaapi_pic(VAPictureH264 *va_pic)
39 {
40  va_pic->picture_id = VA_INVALID_ID;
41  va_pic->flags = VA_PICTURE_H264_INVALID;
42  va_pic->TopFieldOrderCnt = 0;
43  va_pic->BottomFieldOrderCnt = 0;
44 }
45 
46 /**
47  * Translate an FFmpeg Picture into its VA API form.
48  *
49  * @param[out] va_pic A pointer to VA API's own picture struct
50  * @param[in] pic A pointer to the FFmpeg picture struct to convert
51  * @param[in] pic_structure The picture field type (as defined in mpegvideo.h),
52  * supersedes pic's field type if nonzero.
53  */
54 static void fill_vaapi_pic(VAPictureH264 *va_pic,
55  H264Picture *pic,
56  int pic_structure)
57 {
58  if (pic_structure == 0)
59  pic_structure = pic->reference;
60  pic_structure &= PICT_FRAME; /* PICT_TOP_FIELD|PICT_BOTTOM_FIELD */
61 
62  va_pic->picture_id = ff_vaapi_get_surface_id(pic->f);
63  va_pic->frame_idx = pic->long_ref ? pic->pic_id : pic->frame_num;
64 
65  va_pic->flags = 0;
66  if (pic_structure != PICT_FRAME)
67  va_pic->flags |= (pic_structure & PICT_TOP_FIELD) ? VA_PICTURE_H264_TOP_FIELD : VA_PICTURE_H264_BOTTOM_FIELD;
68  if (pic->reference)
69  va_pic->flags |= pic->long_ref ? VA_PICTURE_H264_LONG_TERM_REFERENCE : VA_PICTURE_H264_SHORT_TERM_REFERENCE;
70 
71  va_pic->TopFieldOrderCnt = 0;
72  if (pic->field_poc[0] != INT_MAX)
73  va_pic->TopFieldOrderCnt = pic->field_poc[0];
74 
75  va_pic->BottomFieldOrderCnt = 0;
76  if (pic->field_poc[1] != INT_MAX)
77  va_pic->BottomFieldOrderCnt = pic->field_poc[1];
78 }
79 
80 /** Decoded Picture Buffer (DPB). */
81 typedef struct DPB {
82  int size; ///< Current number of reference frames in the DPB
83  int max_size; ///< Max number of reference frames. This is FF_ARRAY_ELEMS(VAPictureParameterBufferH264.ReferenceFrames)
84  VAPictureH264 *va_pics; ///< Pointer to VAPictureParameterBufferH264.ReferenceFrames array
85 } DPB;
86 
87 /**
88  * Append picture to the decoded picture buffer, in a VA API form that
89  * merges the second field picture attributes with the first, if
90  * available. The decoded picture buffer's size must be large enough
91  * to receive the new VA API picture object.
92  */
93 static int dpb_add(DPB *dpb, H264Picture *pic)
94 {
95  int i;
96 
97  if (dpb->size >= dpb->max_size)
98  return -1;
99 
100  for (i = 0; i < dpb->size; i++) {
101  VAPictureH264 * const va_pic = &dpb->va_pics[i];
102  if (va_pic->picture_id == ff_vaapi_get_surface_id(pic->f)) {
103  VAPictureH264 temp_va_pic;
104  fill_vaapi_pic(&temp_va_pic, pic, 0);
105 
106  if ((temp_va_pic.flags ^ va_pic->flags) & (VA_PICTURE_H264_TOP_FIELD | VA_PICTURE_H264_BOTTOM_FIELD)) {
107  va_pic->flags |= temp_va_pic.flags & (VA_PICTURE_H264_TOP_FIELD | VA_PICTURE_H264_BOTTOM_FIELD);
108  /* Merge second field */
109  if (temp_va_pic.flags & VA_PICTURE_H264_TOP_FIELD) {
110  va_pic->TopFieldOrderCnt = temp_va_pic.TopFieldOrderCnt;
111  } else {
112  va_pic->BottomFieldOrderCnt = temp_va_pic.BottomFieldOrderCnt;
113  }
114  }
115  return 0;
116  }
117  }
118 
119  fill_vaapi_pic(&dpb->va_pics[dpb->size++], pic, 0);
120  return 0;
121 }
122 
123 /** Fill in VA API reference frames array. */
124 static int fill_vaapi_ReferenceFrames(VAPictureParameterBufferH264 *pic_param,
125  H264Context *h)
126 {
127  DPB dpb;
128  int i;
129 
130  dpb.size = 0;
131  dpb.max_size = FF_ARRAY_ELEMS(pic_param->ReferenceFrames);
132  dpb.va_pics = pic_param->ReferenceFrames;
133  for (i = 0; i < dpb.max_size; i++)
134  init_vaapi_pic(&dpb.va_pics[i]);
135 
136  for (i = 0; i < h->short_ref_count; i++) {
137  H264Picture * const pic = h->short_ref[i];
138  if (pic && pic->reference && dpb_add(&dpb, pic) < 0)
139  return -1;
140  }
141 
142  for (i = 0; i < 16; i++) {
143  H264Picture * const pic = h->long_ref[i];
144  if (pic && pic->reference && dpb_add(&dpb, pic) < 0)
145  return -1;
146  }
147  return 0;
148 }
149 
150 /**
151  * Fill in VA API reference picture lists from the FFmpeg reference
152  * picture list.
153  *
154  * @param[out] RefPicList VA API internal reference picture list
155  * @param[in] ref_list A pointer to the FFmpeg reference list
156  * @param[in] ref_count The number of reference pictures in ref_list
157  */
158 static void fill_vaapi_RefPicList(VAPictureH264 RefPicList[32],
159  H264Ref *ref_list,
160  unsigned int ref_count)
161 {
162  unsigned int i, n = 0;
163  for (i = 0; i < ref_count; i++)
164  if (ref_list[i].reference)
165  fill_vaapi_pic(&RefPicList[n++], ref_list[i].parent, 0);
166 
167  for (; n < 32; n++)
168  init_vaapi_pic(&RefPicList[n]);
169 }
170 
171 /**
172  * Fill in prediction weight table.
173  *
174  * VA API requires a plain prediction weight table as it does not infer
175  * any value.
176  *
177  * @param[in] h A pointer to the current H.264 context
178  * @param[in] list The reference frame list index to use
179  * @param[out] luma_weight_flag VA API plain luma weight flag
180  * @param[out] luma_weight VA API plain luma weight table
181  * @param[out] luma_offset VA API plain luma offset table
182  * @param[out] chroma_weight_flag VA API plain chroma weight flag
183  * @param[out] chroma_weight VA API plain chroma weight table
184  * @param[out] chroma_offset VA API plain chroma offset table
185  */
187  int list,
188  unsigned char *luma_weight_flag,
189  short luma_weight[32],
190  short luma_offset[32],
191  unsigned char *chroma_weight_flag,
192  short chroma_weight[32][2],
193  short chroma_offset[32][2])
194 {
195  H264SliceContext *sl = &h->slice_ctx[0];
196  unsigned int i, j;
197 
198  *luma_weight_flag = sl->luma_weight_flag[list];
199  *chroma_weight_flag = sl->chroma_weight_flag[list];
200 
201  for (i = 0; i < sl->ref_count[list]; i++) {
202  /* VA API also wants the inferred (default) values, not
203  only what is available in the bitstream (7.4.3.2). */
204  if (sl->luma_weight_flag[list]) {
205  luma_weight[i] = sl->luma_weight[i][list][0];
206  luma_offset[i] = sl->luma_weight[i][list][1];
207  } else {
208  luma_weight[i] = 1 << sl->luma_log2_weight_denom;
209  luma_offset[i] = 0;
210  }
211  for (j = 0; j < 2; j++) {
212  if (sl->chroma_weight_flag[list]) {
213  chroma_weight[i][j] = sl->chroma_weight[i][list][j][0];
214  chroma_offset[i][j] = sl->chroma_weight[i][list][j][1];
215  } else {
216  chroma_weight[i][j] = 1 << sl->chroma_log2_weight_denom;
217  chroma_offset[i][j] = 0;
218  }
219  }
220  }
221 }
222 
223 /** Initialize and start decoding a frame with VA API. */
225  av_unused const uint8_t *buffer,
226  av_unused uint32_t size)
227 {
228  H264Context * const h = avctx->priv_data;
229  struct vaapi_context * const vactx = avctx->hwaccel_context;
230  VAPictureParameterBufferH264 *pic_param;
231  VAIQMatrixBufferH264 *iq_matrix;
232 
233  ff_dlog(avctx, "vaapi_h264_start_frame()\n");
234 
235  vactx->slice_param_size = sizeof(VASliceParameterBufferH264);
236 
237  /* Fill in VAPictureParameterBufferH264. */
238  pic_param = ff_vaapi_alloc_pic_param(vactx, sizeof(VAPictureParameterBufferH264));
239  if (!pic_param)
240  return -1;
241  fill_vaapi_pic(&pic_param->CurrPic, h->cur_pic_ptr, h->picture_structure);
242  if (fill_vaapi_ReferenceFrames(pic_param, h) < 0)
243  return -1;
244  pic_param->picture_width_in_mbs_minus1 = h->mb_width - 1;
245  pic_param->picture_height_in_mbs_minus1 = h->mb_height - 1;
246  pic_param->bit_depth_luma_minus8 = h->sps.bit_depth_luma - 8;
247  pic_param->bit_depth_chroma_minus8 = h->sps.bit_depth_chroma - 8;
248  pic_param->num_ref_frames = h->sps.ref_frame_count;
249  pic_param->seq_fields.value = 0; /* reset all bits */
250  pic_param->seq_fields.bits.chroma_format_idc = h->sps.chroma_format_idc;
251  pic_param->seq_fields.bits.residual_colour_transform_flag = h->sps.residual_color_transform_flag; /* XXX: only for 4:4:4 high profile? */
252  pic_param->seq_fields.bits.gaps_in_frame_num_value_allowed_flag = h->sps.gaps_in_frame_num_allowed_flag;
253  pic_param->seq_fields.bits.frame_mbs_only_flag = h->sps.frame_mbs_only_flag;
254  pic_param->seq_fields.bits.mb_adaptive_frame_field_flag = h->sps.mb_aff;
255  pic_param->seq_fields.bits.direct_8x8_inference_flag = h->sps.direct_8x8_inference_flag;
256  pic_param->seq_fields.bits.MinLumaBiPredSize8x8 = h->sps.level_idc >= 31; /* A.3.3.2 */
257  pic_param->seq_fields.bits.log2_max_frame_num_minus4 = h->sps.log2_max_frame_num - 4;
258  pic_param->seq_fields.bits.pic_order_cnt_type = h->sps.poc_type;
259  pic_param->seq_fields.bits.log2_max_pic_order_cnt_lsb_minus4 = h->sps.log2_max_poc_lsb - 4;
260  pic_param->seq_fields.bits.delta_pic_order_always_zero_flag = h->sps.delta_pic_order_always_zero_flag;
261  pic_param->num_slice_groups_minus1 = h->pps.slice_group_count - 1;
262  pic_param->slice_group_map_type = h->pps.mb_slice_group_map_type;
263  pic_param->slice_group_change_rate_minus1 = 0; /* XXX: unimplemented in FFmpeg */
264  pic_param->pic_init_qp_minus26 = h->pps.init_qp - 26;
265  pic_param->pic_init_qs_minus26 = h->pps.init_qs - 26;
266  pic_param->chroma_qp_index_offset = h->pps.chroma_qp_index_offset[0];
267  pic_param->second_chroma_qp_index_offset = h->pps.chroma_qp_index_offset[1];
268  pic_param->pic_fields.value = 0; /* reset all bits */
269  pic_param->pic_fields.bits.entropy_coding_mode_flag = h->pps.cabac;
270  pic_param->pic_fields.bits.weighted_pred_flag = h->pps.weighted_pred;
271  pic_param->pic_fields.bits.weighted_bipred_idc = h->pps.weighted_bipred_idc;
272  pic_param->pic_fields.bits.transform_8x8_mode_flag = h->pps.transform_8x8_mode;
273  pic_param->pic_fields.bits.field_pic_flag = h->picture_structure != PICT_FRAME;
274  pic_param->pic_fields.bits.constrained_intra_pred_flag = h->pps.constrained_intra_pred;
275  pic_param->pic_fields.bits.pic_order_present_flag = h->pps.pic_order_present;
276  pic_param->pic_fields.bits.deblocking_filter_control_present_flag = h->pps.deblocking_filter_parameters_present;
277  pic_param->pic_fields.bits.redundant_pic_cnt_present_flag = h->pps.redundant_pic_cnt_present;
278  pic_param->pic_fields.bits.reference_pic_flag = h->nal_ref_idc != 0;
279  pic_param->frame_num = h->frame_num;
280 
281  /* Fill in VAIQMatrixBufferH264. */
282  iq_matrix = ff_vaapi_alloc_iq_matrix(vactx, sizeof(VAIQMatrixBufferH264));
283  if (!iq_matrix)
284  return -1;
285  memcpy(iq_matrix->ScalingList4x4, h->pps.scaling_matrix4, sizeof(iq_matrix->ScalingList4x4));
286  memcpy(iq_matrix->ScalingList8x8[0], h->pps.scaling_matrix8[0], sizeof(iq_matrix->ScalingList8x8[0]));
287  memcpy(iq_matrix->ScalingList8x8[1], h->pps.scaling_matrix8[3], sizeof(iq_matrix->ScalingList8x8[0]));
288  return 0;
289 }
290 
291 /** End a hardware decoding based frame. */
293 {
294  struct vaapi_context * const vactx = avctx->hwaccel_context;
295  H264Context * const h = avctx->priv_data;
296  H264SliceContext *sl = &h->slice_ctx[0];
297  int ret;
298 
299  ff_dlog(avctx, "vaapi_h264_end_frame()\n");
300  ret = ff_vaapi_commit_slices(vactx);
301  if (ret < 0)
302  goto finish;
303 
305  if (ret < 0)
306  goto finish;
307 
308  ff_h264_draw_horiz_band(h, sl, 0, h->avctx->height);
309 
310 finish:
312  return ret;
313 }
314 
315 /** Decode the given H.264 slice with VA API. */
317  const uint8_t *buffer,
318  uint32_t size)
319 {
320  H264Context * const h = avctx->priv_data;
321  H264SliceContext *sl = &h->slice_ctx[0];
322  VASliceParameterBufferH264 *slice_param;
323 
324  ff_dlog(avctx, "vaapi_h264_decode_slice(): buffer %p, size %d\n",
325  buffer, size);
326 
327  /* Fill in VASliceParameterBufferH264. */
328  slice_param = (VASliceParameterBufferH264 *)ff_vaapi_alloc_slice(avctx->hwaccel_context, buffer, size);
329  if (!slice_param)
330  return -1;
331  slice_param->slice_data_bit_offset = get_bits_count(&sl->gb) + 8; /* bit buffer started beyond nal_unit_type */
332  slice_param->first_mb_in_slice = (sl->mb_y >> FIELD_OR_MBAFF_PICTURE(h)) * h->mb_width + sl->mb_x;
333  slice_param->slice_type = ff_h264_get_slice_type(sl);
334  slice_param->direct_spatial_mv_pred_flag = sl->slice_type == AV_PICTURE_TYPE_B ? sl->direct_spatial_mv_pred : 0;
335  slice_param->num_ref_idx_l0_active_minus1 = sl->list_count > 0 ? sl->ref_count[0] - 1 : 0;
336  slice_param->num_ref_idx_l1_active_minus1 = sl->list_count > 1 ? sl->ref_count[1] - 1 : 0;
337  slice_param->cabac_init_idc = sl->cabac_init_idc;
338  slice_param->slice_qp_delta = sl->qscale - h->pps.init_qp;
339  slice_param->disable_deblocking_filter_idc = sl->deblocking_filter < 2 ? !sl->deblocking_filter : sl->deblocking_filter;
340  slice_param->slice_alpha_c0_offset_div2 = sl->slice_alpha_c0_offset / 2;
341  slice_param->slice_beta_offset_div2 = sl->slice_beta_offset / 2;
342  slice_param->luma_log2_weight_denom = sl->luma_log2_weight_denom;
343  slice_param->chroma_log2_weight_denom = sl->chroma_log2_weight_denom;
344 
345  fill_vaapi_RefPicList(slice_param->RefPicList0, sl->ref_list[0], sl->list_count > 0 ? sl->ref_count[0] : 0);
346  fill_vaapi_RefPicList(slice_param->RefPicList1, sl->ref_list[1], sl->list_count > 1 ? sl->ref_count[1] : 0);
347 
349  &slice_param->luma_weight_l0_flag, slice_param->luma_weight_l0, slice_param->luma_offset_l0,
350  &slice_param->chroma_weight_l0_flag, slice_param->chroma_weight_l0, slice_param->chroma_offset_l0);
352  &slice_param->luma_weight_l1_flag, slice_param->luma_weight_l1, slice_param->luma_offset_l1,
353  &slice_param->chroma_weight_l1_flag, slice_param->chroma_weight_l1, slice_param->chroma_offset_l1);
354  return 0;
355 }
356 
358  .name = "h264_vaapi",
359  .type = AVMEDIA_TYPE_VIDEO,
360  .id = AV_CODEC_ID_H264,
361  .pix_fmt = AV_PIX_FMT_VAAPI_VLD,
362  .start_frame = vaapi_h264_start_frame,
363  .end_frame = vaapi_h264_end_frame,
364  .decode_slice = vaapi_h264_decode_slice,
365 };