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vaapi_mpeg2.c
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1 /*
2  * MPEG-2 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 
25 /** Reconstruct bitstream f_code */
26 static inline int mpeg2_get_f_code(MpegEncContext *s)
27 {
28  return (s->mpeg_f_code[0][0] << 12) | (s->mpeg_f_code[0][1] << 8) |
29  (s->mpeg_f_code[1][0] << 4) | s->mpeg_f_code[1][1];
30 }
31 
32 /** Determine frame start: first field for field picture or frame picture */
33 static inline int mpeg2_get_is_frame_start(MpegEncContext *s)
34 {
35  return s->first_field || s->picture_structure == PICT_FRAME;
36 }
37 
38 static int vaapi_mpeg2_start_frame(AVCodecContext *avctx, av_unused const uint8_t *buffer, av_unused uint32_t size)
39 {
40  struct MpegEncContext * const s = avctx->priv_data;
41  struct vaapi_context * const vactx = avctx->hwaccel_context;
42  VAPictureParameterBufferMPEG2 *pic_param;
43  VAIQMatrixBufferMPEG2 *iq_matrix;
44  int i;
45 
46  av_dlog(avctx, "vaapi_mpeg2_start_frame()\n");
47 
48  vactx->slice_param_size = sizeof(VASliceParameterBufferMPEG2);
49 
50  /* Fill in VAPictureParameterBufferMPEG2 */
51  pic_param = ff_vaapi_alloc_pic_param(vactx, sizeof(VAPictureParameterBufferMPEG2));
52  if (!pic_param)
53  return -1;
54  pic_param->horizontal_size = s->width;
55  pic_param->vertical_size = s->height;
56  pic_param->forward_reference_picture = VA_INVALID_ID;
57  pic_param->backward_reference_picture = VA_INVALID_ID;
58  pic_param->picture_coding_type = s->pict_type;
59  pic_param->f_code = mpeg2_get_f_code(s);
60  pic_param->picture_coding_extension.value = 0; /* reset all bits */
61  pic_param->picture_coding_extension.bits.intra_dc_precision = s->intra_dc_precision;
62  pic_param->picture_coding_extension.bits.picture_structure = s->picture_structure;
63  pic_param->picture_coding_extension.bits.top_field_first = s->top_field_first;
64  pic_param->picture_coding_extension.bits.frame_pred_frame_dct = s->frame_pred_frame_dct;
65  pic_param->picture_coding_extension.bits.concealment_motion_vectors = s->concealment_motion_vectors;
66  pic_param->picture_coding_extension.bits.q_scale_type = s->q_scale_type;
67  pic_param->picture_coding_extension.bits.intra_vlc_format = s->intra_vlc_format;
68  pic_param->picture_coding_extension.bits.alternate_scan = s->alternate_scan;
69  pic_param->picture_coding_extension.bits.repeat_first_field = s->repeat_first_field;
70  pic_param->picture_coding_extension.bits.progressive_frame = s->progressive_frame;
71  pic_param->picture_coding_extension.bits.is_first_field = mpeg2_get_is_frame_start(s);
72 
73  switch (s->pict_type) {
74  case AV_PICTURE_TYPE_B:
75  pic_param->backward_reference_picture = ff_vaapi_get_surface_id(&s->next_picture);
76  // fall-through
77  case AV_PICTURE_TYPE_P:
78  pic_param->forward_reference_picture = ff_vaapi_get_surface_id(&s->last_picture);
79  break;
80  }
81 
82  /* Fill in VAIQMatrixBufferMPEG2 */
83  iq_matrix = ff_vaapi_alloc_iq_matrix(vactx, sizeof(VAIQMatrixBufferMPEG2));
84  if (!iq_matrix)
85  return -1;
86  iq_matrix->load_intra_quantiser_matrix = 1;
87  iq_matrix->load_non_intra_quantiser_matrix = 1;
88  iq_matrix->load_chroma_intra_quantiser_matrix = 1;
89  iq_matrix->load_chroma_non_intra_quantiser_matrix = 1;
90 
91  for (i = 0; i < 64; i++) {
92  int n = s->dsp.idct_permutation[ff_zigzag_direct[i]];
93  iq_matrix->intra_quantiser_matrix[i] = s->intra_matrix[n];
94  iq_matrix->non_intra_quantiser_matrix[i] = s->inter_matrix[n];
95  iq_matrix->chroma_intra_quantiser_matrix[i] = s->chroma_intra_matrix[n];
96  iq_matrix->chroma_non_intra_quantiser_matrix[i] = s->chroma_inter_matrix[n];
97  }
98  return 0;
99 }
100 
101 static int vaapi_mpeg2_decode_slice(AVCodecContext *avctx, const uint8_t *buffer, uint32_t size)
102 {
103  MpegEncContext * const s = avctx->priv_data;
104  VASliceParameterBufferMPEG2 *slice_param;
105  GetBitContext gb;
106  uint32_t quantiser_scale_code, intra_slice_flag, macroblock_offset;
107 
108  av_dlog(avctx, "vaapi_mpeg2_decode_slice(): buffer %p, size %d\n", buffer, size);
109 
110  /* Determine macroblock_offset */
111  init_get_bits(&gb, buffer, 8 * size);
112  if (get_bits_long(&gb, 32) >> 8 != 1) /* start code */
113  return AVERROR_INVALIDDATA;
114  quantiser_scale_code = get_bits(&gb, 5);
115  intra_slice_flag = get_bits1(&gb);
116  if (intra_slice_flag) {
117  skip_bits(&gb, 8);
118  if (skip_1stop_8data_bits(&gb) < 0)
119  return AVERROR_INVALIDDATA;
120  }
121  macroblock_offset = get_bits_count(&gb);
122 
123  /* Fill in VASliceParameterBufferMPEG2 */
124  slice_param = (VASliceParameterBufferMPEG2 *)ff_vaapi_alloc_slice(avctx->hwaccel_context, buffer, size);
125  if (!slice_param)
126  return -1;
127  slice_param->macroblock_offset = macroblock_offset;
128  slice_param->slice_horizontal_position = s->mb_x;
129  slice_param->slice_vertical_position = s->mb_y >> (s->picture_structure != PICT_FRAME);
130  slice_param->quantiser_scale_code = quantiser_scale_code;
131  slice_param->intra_slice_flag = intra_slice_flag;
132  return 0;
133 }
134 
135 AVHWAccel ff_mpeg2_vaapi_hwaccel = {
136  .name = "mpeg2_vaapi",
137  .type = AVMEDIA_TYPE_VIDEO,
138  .id = AV_CODEC_ID_MPEG2VIDEO,
139  .pix_fmt = AV_PIX_FMT_VAAPI_VLD,
140  .start_frame = vaapi_mpeg2_start_frame,
141  .end_frame = ff_vaapi_mpeg_end_frame,
142  .decode_slice = vaapi_mpeg2_decode_slice,
143 };
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