vaapi_mpeg2: Constify pointers
[libav.git] / libavcodec / vaapi_mpeg2.c
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 Libav.
7 *
8 * Libav 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 * Libav 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 Libav; 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 "mpegvideo.h"
25 #include "vaapi_internal.h"
26 #include "internal.h"
27
28 /** Reconstruct bitstream f_code */
29 static inline int mpeg2_get_f_code(const MpegEncContext *s)
30 {
31 return (s->mpeg_f_code[0][0] << 12) | (s->mpeg_f_code[0][1] << 8) |
32 (s->mpeg_f_code[1][0] << 4) | s->mpeg_f_code[1][1];
33 }
34
35 /** Determine frame start: first field for field picture or frame picture */
36 static inline int mpeg2_get_is_frame_start(const MpegEncContext *s)
37 {
38 return s->first_field || s->picture_structure == PICT_FRAME;
39 }
40
41 static int vaapi_mpeg2_start_frame(AVCodecContext *avctx, av_unused const uint8_t *buffer, av_unused uint32_t size)
42 {
43 const MpegEncContext *s = avctx->priv_data;
44 struct vaapi_context * const vactx = avctx->hwaccel_context;
45 VAPictureParameterBufferMPEG2 *pic_param;
46 VAIQMatrixBufferMPEG2 *iq_matrix;
47 int i;
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 const MpegEncContext *s = avctx->priv_data;
105 VASliceParameterBufferMPEG2 *slice_param;
106 GetBitContext gb;
107 uint32_t quantiser_scale_code, intra_slice_flag, macroblock_offset;
108
109 /* Determine macroblock_offset */
110 init_get_bits(&gb, buffer, 8 * size);
111 if (get_bits_long(&gb, 32) >> 8 != 1) /* start code */
112 return AVERROR_INVALIDDATA;
113 quantiser_scale_code = get_bits(&gb, 5);
114 intra_slice_flag = get_bits1(&gb);
115 if (intra_slice_flag) {
116 skip_bits(&gb, 8);
117 while (get_bits1(&gb) != 0)
118 skip_bits(&gb, 8);
119 }
120 macroblock_offset = get_bits_count(&gb);
121
122 /* Fill in VASliceParameterBufferMPEG2 */
123 slice_param = (VASliceParameterBufferMPEG2 *)ff_vaapi_alloc_slice(avctx->hwaccel_context, buffer, size);
124 if (!slice_param)
125 return -1;
126 slice_param->macroblock_offset = macroblock_offset;
127 slice_param->slice_horizontal_position = s->mb_x;
128 slice_param->slice_vertical_position = s->mb_y >> (s->picture_structure != PICT_FRAME);
129 slice_param->quantiser_scale_code = quantiser_scale_code;
130 slice_param->intra_slice_flag = intra_slice_flag;
131 return 0;
132 }
133
134 AVHWAccel ff_mpeg2_vaapi_hwaccel = {
135 .name = "mpeg2_vaapi",
136 .type = AVMEDIA_TYPE_VIDEO,
137 .id = AV_CODEC_ID_MPEG2VIDEO,
138 .pix_fmt = AV_PIX_FMT_VAAPI,
139 .start_frame = vaapi_mpeg2_start_frame,
140 .end_frame = ff_vaapi_mpeg_end_frame,
141 .decode_slice = vaapi_mpeg2_decode_slice,
142 };