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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 "mpegutils.h"
24 #include "vaapi_internal.h"
25 
26 /** Reconstruct bitstream f_code */
27 static inline int mpeg2_get_f_code(MpegEncContext *s)
28 {
29  return (s->mpeg_f_code[0][0] << 12) | (s->mpeg_f_code[0][1] << 8) |
30  (s->mpeg_f_code[1][0] << 4) | s->mpeg_f_code[1][1];
31 }
32 
33 /** Determine frame start: first field for field picture or frame picture */
34 static inline int mpeg2_get_is_frame_start(MpegEncContext *s)
35 {
36  return s->first_field || s->picture_structure == PICT_FRAME;
37 }
38 
39 static int vaapi_mpeg2_start_frame(AVCodecContext *avctx, av_unused const uint8_t *buffer, av_unused uint32_t size)
40 {
41  struct MpegEncContext * const s = avctx->priv_data;
42  struct vaapi_context * const vactx = avctx->hwaccel_context;
43  VAPictureParameterBufferMPEG2 *pic_param;
44  VAIQMatrixBufferMPEG2 *iq_matrix;
45  int i;
46 
47  av_dlog(avctx, "vaapi_mpeg2_start_frame()\n");
48 
49  vactx->slice_param_size = sizeof(VASliceParameterBufferMPEG2);
50 
51  /* Fill in VAPictureParameterBufferMPEG2 */
52  pic_param = ff_vaapi_alloc_pic_param(vactx, sizeof(VAPictureParameterBufferMPEG2));
53  if (!pic_param)
54  return -1;
55  pic_param->horizontal_size = s->width;
56  pic_param->vertical_size = s->height;
57  pic_param->forward_reference_picture = VA_INVALID_ID;
58  pic_param->backward_reference_picture = VA_INVALID_ID;
59  pic_param->picture_coding_type = s->pict_type;
60  pic_param->f_code = mpeg2_get_f_code(s);
61  pic_param->picture_coding_extension.value = 0; /* reset all bits */
62  pic_param->picture_coding_extension.bits.intra_dc_precision = s->intra_dc_precision;
63  pic_param->picture_coding_extension.bits.picture_structure = s->picture_structure;
64  pic_param->picture_coding_extension.bits.top_field_first = s->top_field_first;
65  pic_param->picture_coding_extension.bits.frame_pred_frame_dct = s->frame_pred_frame_dct;
66  pic_param->picture_coding_extension.bits.concealment_motion_vectors = s->concealment_motion_vectors;
67  pic_param->picture_coding_extension.bits.q_scale_type = s->q_scale_type;
68  pic_param->picture_coding_extension.bits.intra_vlc_format = s->intra_vlc_format;
69  pic_param->picture_coding_extension.bits.alternate_scan = s->alternate_scan;
70  pic_param->picture_coding_extension.bits.repeat_first_field = s->repeat_first_field;
71  pic_param->picture_coding_extension.bits.progressive_frame = s->progressive_frame;
72  pic_param->picture_coding_extension.bits.is_first_field = mpeg2_get_is_frame_start(s);
73 
74  switch (s->pict_type) {
75  case AV_PICTURE_TYPE_B:
76  pic_param->backward_reference_picture = ff_vaapi_get_surface_id(s->next_picture.f);
77  // fall-through
78  case AV_PICTURE_TYPE_P:
79  pic_param->forward_reference_picture = ff_vaapi_get_surface_id(s->last_picture.f);
80  break;
81  }
82 
83  /* Fill in VAIQMatrixBufferMPEG2 */
84  iq_matrix = ff_vaapi_alloc_iq_matrix(vactx, sizeof(VAIQMatrixBufferMPEG2));
85  if (!iq_matrix)
86  return -1;
87  iq_matrix->load_intra_quantiser_matrix = 1;
88  iq_matrix->load_non_intra_quantiser_matrix = 1;
89  iq_matrix->load_chroma_intra_quantiser_matrix = 1;
90  iq_matrix->load_chroma_non_intra_quantiser_matrix = 1;
91 
92  for (i = 0; i < 64; i++) {
93  int n = s->idsp.idct_permutation[ff_zigzag_direct[i]];
94  iq_matrix->intra_quantiser_matrix[i] = s->intra_matrix[n];
95  iq_matrix->non_intra_quantiser_matrix[i] = s->inter_matrix[n];
96  iq_matrix->chroma_intra_quantiser_matrix[i] = s->chroma_intra_matrix[n];
97  iq_matrix->chroma_non_intra_quantiser_matrix[i] = s->chroma_inter_matrix[n];
98  }
99  return 0;
100 }
101 
102 static int vaapi_mpeg2_decode_slice(AVCodecContext *avctx, const uint8_t *buffer, uint32_t size)
103 {
104  MpegEncContext * const s = avctx->priv_data;
105  VASliceParameterBufferMPEG2 *slice_param;
106  GetBitContext gb;
107  uint32_t quantiser_scale_code, intra_slice_flag, macroblock_offset;
108 
109  av_dlog(avctx, "vaapi_mpeg2_decode_slice(): buffer %p, size %d\n", buffer, size);
110 
111  /* Determine macroblock_offset */
112  init_get_bits(&gb, buffer, 8 * size);
113  if (get_bits_long(&gb, 32) >> 8 != 1) /* start code */
114  return AVERROR_INVALIDDATA;
115  quantiser_scale_code = get_bits(&gb, 5);
116  intra_slice_flag = get_bits1(&gb);
117  if (intra_slice_flag) {
118  skip_bits(&gb, 8);
119  if (skip_1stop_8data_bits(&gb) < 0)
120  return AVERROR_INVALIDDATA;
121  }
122  macroblock_offset = get_bits_count(&gb);
123 
124  /* Fill in VASliceParameterBufferMPEG2 */
125  slice_param = (VASliceParameterBufferMPEG2 *)ff_vaapi_alloc_slice(avctx->hwaccel_context, buffer, size);
126  if (!slice_param)
127  return -1;
128  slice_param->macroblock_offset = macroblock_offset;
129  slice_param->slice_horizontal_position = s->mb_x;
130  slice_param->slice_vertical_position = s->mb_y >> (s->picture_structure != PICT_FRAME);
131  slice_param->quantiser_scale_code = quantiser_scale_code;
132  slice_param->intra_slice_flag = intra_slice_flag;
133  return 0;
134 }
135 
136 AVHWAccel ff_mpeg2_vaapi_hwaccel = {
137  .name = "mpeg2_vaapi",
138  .type = AVMEDIA_TYPE_VIDEO,
139  .id = AV_CODEC_ID_MPEG2VIDEO,
140  .pix_fmt = AV_PIX_FMT_VAAPI_VLD,
141  .start_frame = vaapi_mpeg2_start_frame,
142  .end_frame = ff_vaapi_mpeg_end_frame,
143  .decode_slice = vaapi_mpeg2_decode_slice,
144 };
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