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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 #include "internal.h"
26 
27 /** Reconstruct bitstream f_code */
28 static inline int mpeg2_get_f_code(MpegEncContext *s)
29 {
30  return (s->mpeg_f_code[0][0] << 12) | (s->mpeg_f_code[0][1] << 8) |
31  (s->mpeg_f_code[1][0] << 4) | s->mpeg_f_code[1][1];
32 }
33 
34 /** Determine frame start: first field for field picture or frame picture */
36 {
37  return s->first_field || s->picture_structure == PICT_FRAME;
38 }
39 
41 {
42  struct MpegEncContext * const s = avctx->priv_data;
43  struct vaapi_context * const vactx = avctx->hwaccel_context;
44  VAPictureParameterBufferMPEG2 *pic_param;
45  VAIQMatrixBufferMPEG2 *iq_matrix;
46  int i;
47 
48  ff_dlog(avctx, "vaapi_mpeg2_start_frame()\n");
49 
50  vactx->slice_param_size = sizeof(VASliceParameterBufferMPEG2);
51 
52  /* Fill in VAPictureParameterBufferMPEG2 */
53  pic_param = ff_vaapi_alloc_pic_param(vactx, sizeof(VAPictureParameterBufferMPEG2));
54  if (!pic_param)
55  return -1;
56  pic_param->horizontal_size = s->width;
57  pic_param->vertical_size = s->height;
58  pic_param->forward_reference_picture = VA_INVALID_ID;
59  pic_param->backward_reference_picture = VA_INVALID_ID;
60  pic_param->picture_coding_type = s->pict_type;
61  pic_param->f_code = mpeg2_get_f_code(s);
62  pic_param->picture_coding_extension.value = 0; /* reset all bits */
63  pic_param->picture_coding_extension.bits.intra_dc_precision = s->intra_dc_precision;
64  pic_param->picture_coding_extension.bits.picture_structure = s->picture_structure;
65  pic_param->picture_coding_extension.bits.top_field_first = s->top_field_first;
66  pic_param->picture_coding_extension.bits.frame_pred_frame_dct = s->frame_pred_frame_dct;
67  pic_param->picture_coding_extension.bits.concealment_motion_vectors = s->concealment_motion_vectors;
68  pic_param->picture_coding_extension.bits.q_scale_type = s->q_scale_type;
69  pic_param->picture_coding_extension.bits.intra_vlc_format = s->intra_vlc_format;
70  pic_param->picture_coding_extension.bits.alternate_scan = s->alternate_scan;
71  pic_param->picture_coding_extension.bits.repeat_first_field = s->repeat_first_field;
72  pic_param->picture_coding_extension.bits.progressive_frame = s->progressive_frame;
73  pic_param->picture_coding_extension.bits.is_first_field = mpeg2_get_is_frame_start(s);
74 
75  switch (s->pict_type) {
76  case AV_PICTURE_TYPE_B:
77  pic_param->backward_reference_picture = ff_vaapi_get_surface_id(s->next_picture.f);
78  // fall-through
79  case AV_PICTURE_TYPE_P:
80  pic_param->forward_reference_picture = ff_vaapi_get_surface_id(s->last_picture.f);
81  break;
82  }
83 
84  /* Fill in VAIQMatrixBufferMPEG2 */
85  iq_matrix = ff_vaapi_alloc_iq_matrix(vactx, sizeof(VAIQMatrixBufferMPEG2));
86  if (!iq_matrix)
87  return -1;
88  iq_matrix->load_intra_quantiser_matrix = 1;
89  iq_matrix->load_non_intra_quantiser_matrix = 1;
90  iq_matrix->load_chroma_intra_quantiser_matrix = 1;
91  iq_matrix->load_chroma_non_intra_quantiser_matrix = 1;
92 
93  for (i = 0; i < 64; i++) {
95  iq_matrix->intra_quantiser_matrix[i] = s->intra_matrix[n];
96  iq_matrix->non_intra_quantiser_matrix[i] = s->inter_matrix[n];
97  iq_matrix->chroma_intra_quantiser_matrix[i] = s->chroma_intra_matrix[n];
98  iq_matrix->chroma_non_intra_quantiser_matrix[i] = s->chroma_inter_matrix[n];
99  }
100  return 0;
101 }
102 
103 static int vaapi_mpeg2_decode_slice(AVCodecContext *avctx, const uint8_t *buffer, uint32_t size)
104 {
105  MpegEncContext * const s = avctx->priv_data;
106  VASliceParameterBufferMPEG2 *slice_param;
107  GetBitContext gb;
108  uint32_t quantiser_scale_code, intra_slice_flag, macroblock_offset;
109 
110  ff_dlog(avctx, "vaapi_mpeg2_decode_slice(): buffer %p, size %d\n", buffer, size);
111 
112  /* Determine macroblock_offset */
113  init_get_bits(&gb, buffer, 8 * size);
114  if (get_bits_long(&gb, 32) >> 8 != 1) /* start code */
115  return AVERROR_INVALIDDATA;
116  quantiser_scale_code = get_bits(&gb, 5);
117  intra_slice_flag = get_bits1(&gb);
118  if (intra_slice_flag) {
119  skip_bits(&gb, 8);
120  if (skip_1stop_8data_bits(&gb) < 0)
121  return AVERROR_INVALIDDATA;
122  }
123  macroblock_offset = get_bits_count(&gb);
124 
125  /* Fill in VASliceParameterBufferMPEG2 */
126  slice_param = (VASliceParameterBufferMPEG2 *)ff_vaapi_alloc_slice(avctx->hwaccel_context, buffer, size);
127  if (!slice_param)
128  return -1;
129  slice_param->macroblock_offset = macroblock_offset;
130  slice_param->slice_horizontal_position = s->mb_x;
131  slice_param->slice_vertical_position = s->mb_y >> (s->picture_structure != PICT_FRAME);
132  slice_param->quantiser_scale_code = quantiser_scale_code;
133  slice_param->intra_slice_flag = intra_slice_flag;
134  return 0;
135 }
136 
138  .name = "mpeg2_vaapi",
139  .type = AVMEDIA_TYPE_VIDEO,
141  .pix_fmt = AV_PIX_FMT_VAAPI_VLD,
142  .start_frame = vaapi_mpeg2_start_frame,
143  .end_frame = ff_vaapi_mpeg_end_frame,
144  .decode_slice = vaapi_mpeg2_decode_slice,
145 };