Remove useless line.
[ffmpeg.git] / libavcodec / vaapi_h264.c
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
26 /** @file
27  *  This file implements the glue code between FFmpeg's and VA API's
28  *  structures for H.264 decoding.
29  */
30
31 /** Reconstructs bitstream slice_type. */
32 static int get_slice_type(H264Context *h)
33 {
34     switch (h->slice_type) {
35     case FF_P_TYPE:  return 0;
36     case FF_B_TYPE:  return 1;
37     case FF_I_TYPE:  return 2;
38     case FF_SP_TYPE: return 3;
39     case FF_SI_TYPE: return 4;
40     default:         return -1;
41     }
42 }
43
44 /**
45  * Initializes an empty VA API picture.
46  *
47  * VA API requires a fixed-size reference picture array.
48  */
49 static void init_vaapi_pic(VAPictureH264 *va_pic)
50 {
51     va_pic->picture_id          = VA_INVALID_ID;
52     va_pic->flags               = VA_PICTURE_H264_INVALID;
53     va_pic->TopFieldOrderCnt    = 0;
54     va_pic->BottomFieldOrderCnt = 0;
55 }
56
57 /**
58  * Translates an FFmpeg Picture into its VA API form.
59  *
60  * @param[out] va_pic          A pointer to VA API's own picture struct
61  * @param[in]  pic             A pointer to the FFmpeg picture struct to convert
62  * @param[in]  pic_structure   The picture field type (as defined in mpegvideo.h),
63  *                             supersedes pic's field type if nonzero.
64  */
65 static void fill_vaapi_pic(VAPictureH264 *va_pic,
66                            Picture       *pic,
67                            int            pic_structure)
68 {
69     if (pic_structure == 0)
70         pic_structure = pic->reference;
71
72     va_pic->picture_id = ff_vaapi_get_surface_id(pic);
73     va_pic->frame_idx  = pic->long_ref ? pic->pic_id : pic->frame_num;
74
75     va_pic->flags      = 0;
76     if (pic_structure != PICT_FRAME)
77         va_pic->flags |= (pic_structure & PICT_TOP_FIELD) ? VA_PICTURE_H264_TOP_FIELD : VA_PICTURE_H264_BOTTOM_FIELD;
78     if (pic->reference)
79         va_pic->flags |= pic->long_ref ? VA_PICTURE_H264_LONG_TERM_REFERENCE : VA_PICTURE_H264_SHORT_TERM_REFERENCE;
80
81     va_pic->TopFieldOrderCnt = 0;
82     if (pic->field_poc[0] != INT_MAX)
83         va_pic->TopFieldOrderCnt = pic->field_poc[0];
84
85     va_pic->BottomFieldOrderCnt = 0;
86     if (pic->field_poc[1] != INT_MAX)
87         va_pic->BottomFieldOrderCnt = pic->field_poc[1];
88 }
89
90 /** Decoded Picture Buffer (DPB). */
91 typedef struct DPB {
92     int            size;        ///< Current number of reference frames in the DPB
93     int            max_size;    ///< Max number of reference frames. This is FF_ARRAY_ELEMS(VAPictureParameterBufferH264.ReferenceFrames)
94     VAPictureH264 *va_pics;     ///< Pointer to VAPictureParameterBufferH264.ReferenceFrames array
95 } DPB;
96
97 /**
98  * Appends picture to the decoded picture buffer, in a VA API form that
99  * merges the second field picture attributes with the first, if
100  * available.  The decoded picture buffer's size must be large enough
101  * to receive the new VA API picture object.
102  */
103 static int dpb_add(DPB *dpb, Picture *pic)
104 {
105     int i;
106
107     if (dpb->size >= dpb->max_size)
108         return -1;
109
110     for (i = 0; i < dpb->size; i++) {
111         VAPictureH264 * const va_pic = &dpb->va_pics[i];
112         if (va_pic->picture_id == ff_vaapi_get_surface_id(pic)) {
113             VAPictureH264 temp_va_pic;
114             fill_vaapi_pic(&temp_va_pic, pic, 0);
115
116             if ((temp_va_pic.flags ^ va_pic->flags) & (VA_PICTURE_H264_TOP_FIELD | VA_PICTURE_H264_BOTTOM_FIELD)) {
117                 va_pic->flags |= temp_va_pic.flags & (VA_PICTURE_H264_TOP_FIELD | VA_PICTURE_H264_BOTTOM_FIELD);
118                 /* Merge second field */
119                 if (temp_va_pic.flags & VA_PICTURE_H264_TOP_FIELD) {
120                     va_pic->TopFieldOrderCnt    = temp_va_pic.TopFieldOrderCnt;
121                 } else {
122                     va_pic->BottomFieldOrderCnt = temp_va_pic.BottomFieldOrderCnt;
123                 }
124             }
125             return 0;
126         }
127     }
128
129     fill_vaapi_pic(&dpb->va_pics[dpb->size++], pic, 0);
130     return 0;
131 }
132
133 /** Fills in VA API reference frames array. */
134 static int fill_vaapi_ReferenceFrames(VAPictureParameterBufferH264 *pic_param,
135                                       H264Context                  *h)
136 {
137     DPB dpb;
138     int i;
139
140     dpb.size     = 0;
141     dpb.max_size = FF_ARRAY_ELEMS(pic_param->ReferenceFrames);
142     dpb.va_pics  = pic_param->ReferenceFrames;
143     for (i = 0; i < dpb.max_size; i++)
144         init_vaapi_pic(&dpb.va_pics[i]);
145
146     for (i = 0; i < h->short_ref_count; i++) {
147         Picture * const pic = h->short_ref[i];
148         if (pic && pic->reference && dpb_add(&dpb, pic) < 0)
149             return -1;
150     }
151
152     for (i = 0; i < h->long_ref_count; i++) {
153         Picture * const pic = h->long_ref[i];
154         if (pic && pic->reference && dpb_add(&dpb, pic) < 0)
155             return -1;
156     }
157     return 0;
158 }
159
160 /**
161  * Fills in VA API reference picture lists from the FFmpeg reference
162  * picture list.
163  *
164  * @param[out] RefPicList  VA API internal reference picture list
165  * @param[in]  ref_list    A pointer to the FFmpeg reference list
166  * @param[in]  ref_count   The number of reference pictures in ref_list
167  */
168 static void fill_vaapi_RefPicList(VAPictureH264 RefPicList[32],
169                                   Picture      *ref_list,
170                                   unsigned int  ref_count)
171 {
172     unsigned int i, n = 0;
173     for (i = 0; i < ref_count; i++)
174         if (ref_list[i].reference)
175             fill_vaapi_pic(&RefPicList[n++], &ref_list[i], 0);
176
177     for (; n < 32; n++)
178         init_vaapi_pic(&RefPicList[n]);
179 }
180
181 /**
182  * Fills in prediction weight table.
183  *
184  * VA API requires a plain prediction weight table as it does not infer
185  * any value.
186  *
187  * @param[in]  h                   A pointer to the current H.264 context
188  * @param[in]  list                The reference frame list index to use
189  * @param[out] luma_weight_flag    VA API plain luma weight flag
190  * @param[out] luma_weight         VA API plain luma weight table
191  * @param[out] luma_offset         VA API plain luma offset table
192  * @param[out] chroma_weight_flag  VA API plain chroma weight flag
193  * @param[out] chroma_weight       VA API plain chroma weight table
194  * @param[out] chroma_offset       VA API plain chroma offset table
195  */
196 static void fill_vaapi_plain_pred_weight_table(H264Context   *h,
197                                                int            list,
198                                                unsigned char *luma_weight_flag,
199                                                short          luma_weight[32],
200                                                short          luma_offset[32],
201                                                unsigned char *chroma_weight_flag,
202                                                short          chroma_weight[32][2],
203                                                short          chroma_offset[32][2])
204 {
205     unsigned int i, j;
206
207     *luma_weight_flag    = h->luma_weight_flag[list];
208     *chroma_weight_flag  = h->chroma_weight_flag[list];
209
210     for (i = 0; i < h->ref_count[list]; i++) {
211         /* VA API also wants the inferred (default) values, not
212            only what is available in the bitstream (7.4.3.2). */
213         if (h->luma_weight_flag[list]) {
214             luma_weight[i] = h->luma_weight[list][i];
215             luma_offset[i] = h->luma_offset[list][i];
216         } else {
217             luma_weight[i] = 1 << h->luma_log2_weight_denom;
218             luma_offset[i] = 0;
219         }
220         for (j = 0; j < 2; j++) {
221             if (h->chroma_weight_flag[list]) {
222                 chroma_weight[i][j] = h->chroma_weight[list][i][j];
223                 chroma_offset[i][j] = h->chroma_offset[list][i][j];
224             } else {
225                 chroma_weight[i][j] = 1 << h->chroma_log2_weight_denom;
226                 chroma_offset[i][j] = 0;
227             }
228         }
229     }
230 }
231
232 /** Initializes and starts decoding a frame with VA API. */
233 static int start_frame(AVCodecContext          *avctx,
234                        av_unused const uint8_t *buffer,
235                        av_unused uint32_t       size)
236 {
237     H264Context * const h = avctx->priv_data;
238     MpegEncContext * const s = &h->s;
239     struct vaapi_context * const vactx = avctx->hwaccel_context;
240     VAPictureParameterBufferH264 *pic_param;
241     VAIQMatrixBufferH264 *iq_matrix;
242
243     dprintf(avctx, "start_frame()\n");
244
245     vactx->slice_param_size = sizeof(VASliceParameterBufferH264);
246
247     /* Fill in VAPictureParameterBufferH264. */
248     pic_param = ff_vaapi_alloc_pic_param(vactx, sizeof(VAPictureParameterBufferH264));
249     if (!pic_param)
250         return -1;
251     fill_vaapi_pic(&pic_param->CurrPic, s->current_picture_ptr, s->picture_structure);
252     if (fill_vaapi_ReferenceFrames(pic_param, h) < 0)
253         return -1;
254     pic_param->picture_width_in_mbs_minus1                      = s->mb_width - 1;
255     pic_param->picture_height_in_mbs_minus1                     = s->mb_height - 1;
256     pic_param->bit_depth_luma_minus8                            = h->sps.bit_depth_luma - 8;
257     pic_param->bit_depth_chroma_minus8                          = h->sps.bit_depth_chroma - 8;
258     pic_param->num_ref_frames                                   = h->sps.ref_frame_count;
259     pic_param->seq_fields.value                                 = 0; /* reset all bits */
260     pic_param->seq_fields.bits.chroma_format_idc                = h->sps.chroma_format_idc;
261     pic_param->seq_fields.bits.residual_colour_transform_flag   = h->sps.residual_color_transform_flag; /* XXX: only for 4:4:4 high profile? */
262     pic_param->seq_fields.bits.gaps_in_frame_num_value_allowed_flag = h->sps.gaps_in_frame_num_allowed_flag;
263     pic_param->seq_fields.bits.frame_mbs_only_flag              = h->sps.frame_mbs_only_flag;
264     pic_param->seq_fields.bits.mb_adaptive_frame_field_flag     = h->sps.mb_aff;
265     pic_param->seq_fields.bits.direct_8x8_inference_flag        = h->sps.direct_8x8_inference_flag;
266     pic_param->seq_fields.bits.MinLumaBiPredSize8x8             = h->sps.level_idc >= 31; /* A.3.3.2 */
267     pic_param->seq_fields.bits.log2_max_frame_num_minus4        = h->sps.log2_max_frame_num - 4;
268     pic_param->seq_fields.bits.pic_order_cnt_type               = h->sps.poc_type;
269     pic_param->seq_fields.bits.log2_max_pic_order_cnt_lsb_minus4 = h->sps.log2_max_poc_lsb - 4;
270     pic_param->seq_fields.bits.delta_pic_order_always_zero_flag = h->sps.delta_pic_order_always_zero_flag;
271     pic_param->num_slice_groups_minus1                          = h->pps.slice_group_count - 1;
272     pic_param->slice_group_map_type                             = h->pps.mb_slice_group_map_type;
273     pic_param->slice_group_change_rate_minus1                   = 0; /* XXX: unimplemented in FFmpeg */
274     pic_param->pic_init_qp_minus26                              = h->pps.init_qp - 26;
275     pic_param->pic_init_qs_minus26                              = h->pps.init_qs - 26;
276     pic_param->chroma_qp_index_offset                           = h->pps.chroma_qp_index_offset[0];
277     pic_param->second_chroma_qp_index_offset                    = h->pps.chroma_qp_index_offset[1];
278     pic_param->pic_fields.value                                 = 0; /* reset all bits */
279     pic_param->pic_fields.bits.entropy_coding_mode_flag         = h->pps.cabac;
280     pic_param->pic_fields.bits.weighted_pred_flag               = h->pps.weighted_pred;
281     pic_param->pic_fields.bits.weighted_bipred_idc              = h->pps.weighted_bipred_idc;
282     pic_param->pic_fields.bits.transform_8x8_mode_flag          = h->pps.transform_8x8_mode;
283     pic_param->pic_fields.bits.field_pic_flag                   = s->picture_structure != PICT_FRAME;
284     pic_param->pic_fields.bits.constrained_intra_pred_flag      = h->pps.constrained_intra_pred;
285     pic_param->pic_fields.bits.pic_order_present_flag           = h->pps.pic_order_present;
286     pic_param->pic_fields.bits.deblocking_filter_control_present_flag = h->pps.deblocking_filter_parameters_present;
287     pic_param->pic_fields.bits.redundant_pic_cnt_present_flag   = h->pps.redundant_pic_cnt_present;
288     pic_param->pic_fields.bits.reference_pic_flag               = h->nal_ref_idc != 0;
289     pic_param->frame_num                                        = h->frame_num;
290
291     /* Fill in VAIQMatrixBufferH264. */
292     iq_matrix = ff_vaapi_alloc_iq_matrix(vactx, sizeof(VAIQMatrixBufferH264));
293     if (!iq_matrix)
294         return -1;
295     memcpy(iq_matrix->ScalingList4x4, h->pps.scaling_matrix4, sizeof(iq_matrix->ScalingList4x4));
296     memcpy(iq_matrix->ScalingList8x8, h->pps.scaling_matrix8, sizeof(iq_matrix->ScalingList8x8));
297     return 0;
298 }
299
300 /** Ends a hardware decoding based frame. */
301 static int end_frame(AVCodecContext *avctx)
302 {
303     H264Context * const h = avctx->priv_data;
304
305     dprintf(avctx, "end_frame()\n");
306     return ff_vaapi_common_end_frame(&h->s);
307 }
308
309 /** Decodes the given H.264 slice with VA API. */
310 static int decode_slice(AVCodecContext *avctx,
311                         const uint8_t  *buffer,
312                         uint32_t        size)
313 {
314     H264Context * const h = avctx->priv_data;
315     MpegEncContext * const s = &h->s;
316     VASliceParameterBufferH264 *slice_param;
317
318     dprintf(avctx, "decode_slice(): buffer %p, size %d\n", buffer, size);
319
320     /* Fill in VASliceParameterBufferH264. */
321     slice_param = (VASliceParameterBufferH264 *)ff_vaapi_alloc_slice(avctx->hwaccel_context, buffer, size);
322     if (!slice_param)
323         return -1;
324     slice_param->slice_data_bit_offset          = get_bits_count(&h->s.gb) + 8; /* bit buffer started beyond nal_unit_type */
325     slice_param->first_mb_in_slice              = (s->mb_y >> FIELD_OR_MBAFF_PICTURE) * s->mb_width + s->mb_x;
326     slice_param->slice_type                     = get_slice_type(h);
327     slice_param->direct_spatial_mv_pred_flag    = h->slice_type == FF_B_TYPE ? h->direct_spatial_mv_pred : 0;
328     slice_param->num_ref_idx_l0_active_minus1   = h->list_count > 0 ? h->ref_count[0] - 1 : 0;
329     slice_param->num_ref_idx_l1_active_minus1   = h->list_count > 1 ? h->ref_count[1] - 1 : 0;
330     slice_param->cabac_init_idc                 = h->cabac_init_idc;
331     slice_param->slice_qp_delta                 = s->qscale - h->pps.init_qp;
332     slice_param->disable_deblocking_filter_idc  = h->deblocking_filter < 2 ? !h->deblocking_filter : h->deblocking_filter;
333     slice_param->slice_alpha_c0_offset_div2     = h->slice_alpha_c0_offset / 2;
334     slice_param->slice_beta_offset_div2         = h->slice_beta_offset / 2;
335     slice_param->luma_log2_weight_denom         = h->luma_log2_weight_denom;
336     slice_param->chroma_log2_weight_denom       = h->chroma_log2_weight_denom;
337
338     fill_vaapi_RefPicList(slice_param->RefPicList0, h->ref_list[0], h->list_count > 0 ? h->ref_count[0] : 0);
339     fill_vaapi_RefPicList(slice_param->RefPicList1, h->ref_list[1], h->list_count > 1 ? h->ref_count[1] : 0);
340
341     fill_vaapi_plain_pred_weight_table(h, 0,
342                                        &slice_param->luma_weight_l0_flag,   slice_param->luma_weight_l0,   slice_param->luma_offset_l0,
343                                        &slice_param->chroma_weight_l0_flag, slice_param->chroma_weight_l0, slice_param->chroma_offset_l0);
344     fill_vaapi_plain_pred_weight_table(h, 1,
345                                        &slice_param->luma_weight_l1_flag,   slice_param->luma_weight_l1,   slice_param->luma_offset_l1,
346                                        &slice_param->chroma_weight_l1_flag, slice_param->chroma_weight_l1, slice_param->chroma_offset_l1);
347     return 0;
348 }
349
350 AVHWAccel h264_vaapi_hwaccel = {
351     .name           = "h264_vaapi",
352     .type           = CODEC_TYPE_VIDEO,
353     .id             = CODEC_ID_H264,
354     .pix_fmt        = PIX_FMT_VAAPI_VLD,
355     .capabilities   = 0,
356     .start_frame    = start_frame,
357     .end_frame      = end_frame,
358     .decode_slice   = decode_slice,
359     .priv_data_size = 0,
360 };