1 /*
2  * MPEG-4 Part 2 HW decode acceleration through NVDEC
3  *
4  * Copyright (c) 2017 Philip Langdale
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 "avcodec.h"
24 #include "mpeg4video.h"
25 #include "nvdec.h"
26 #include "decode.h"
27 
nvdec_mpeg4_start_frame(AVCodecContext * avctx,const uint8_t * buffer,uint32_t size)28 static int nvdec_mpeg4_start_frame(AVCodecContext *avctx, const uint8_t *buffer, uint32_t size)
29 {
30     Mpeg4DecContext *m = avctx->priv_data;
31     MpegEncContext *s = &m->m;
32 
33     NVDECContext      *ctx = avctx->internal->hwaccel_priv_data;
34     CUVIDPICPARAMS     *pp = &ctx->pic_params;
35     CUVIDMPEG4PICPARAMS *ppc = &pp->CodecSpecific.mpeg4;
36     FrameDecodeData *fdd;
37     NVDECFrame *cf;
38     AVFrame *cur_frame = s->current_picture.f;
39 
40     int ret, i;
41 
42     ret = ff_nvdec_start_frame(avctx, cur_frame);
43     if (ret < 0)
44         return ret;
45 
46     fdd = (FrameDecodeData*)cur_frame->private_ref->data;
47     cf  = (NVDECFrame*)fdd->hwaccel_priv;
48 
49     *pp = (CUVIDPICPARAMS) {
50         .PicWidthInMbs     = (cur_frame->width  + 15) / 16,
51         .FrameHeightInMbs  = (cur_frame->height + 15) / 16,
52         .CurrPicIdx        = cf->idx,
53 
54         .intra_pic_flag    = s->pict_type == AV_PICTURE_TYPE_I,
55         .ref_pic_flag      = s->pict_type == AV_PICTURE_TYPE_I ||
56                              s->pict_type == AV_PICTURE_TYPE_P ||
57                              s->pict_type == AV_PICTURE_TYPE_S,
58 
59         .CodecSpecific.mpeg4 = {
60             .ForwardRefIdx                = ff_nvdec_get_ref_idx(s->last_picture.f),
61             .BackwardRefIdx               = ff_nvdec_get_ref_idx(s->next_picture.f),
62 
63             .video_object_layer_width     = s->width,
64             .video_object_layer_height    = s->height,
65             .vop_time_increment_bitcount  = m->time_increment_bits,
66             .top_field_first              = s->top_field_first,
67             .resync_marker_disable        = !m->resync_marker,
68             .quant_type                   = s->mpeg_quant,
69             .quarter_sample               = s->quarter_sample,
70             .short_video_header           = avctx->codec->id == AV_CODEC_ID_H263,
71             .divx_flags                   = s->divx_packed ? 5 : 0,
72 
73             .vop_coding_type              = s->pict_type - AV_PICTURE_TYPE_I,
74             .vop_coded                    = 1,
75             .vop_rounding_type            = s->no_rounding,
76             .alternate_vertical_scan_flag = s->alternate_scan,
77             .interlaced                   = !s->progressive_sequence,
78             .vop_fcode_forward            = s->f_code,
79             .vop_fcode_backward           = s->b_code,
80             .trd                          = { s->pp_time, s->pp_field_time >> 1 },
81             .trb                          = { s->pb_time, s->pb_field_time >> 1 },
82 
83             .gmc_enabled                  = s->pict_type == AV_PICTURE_TYPE_S &&
84                                             m->vol_sprite_usage == GMC_SPRITE,
85         }
86     };
87 
88     for (i = 0; i < 64; ++i) {
89         ppc->QuantMatrixIntra[i] = s->intra_matrix[i];
90         ppc->QuantMatrixInter[i] = s->inter_matrix[i];
91     }
92 
93     // We need to pass the full frame buffer and not just the slice
94     return ff_nvdec_simple_decode_slice(avctx, buffer, size);
95 }
96 
nvdec_mpeg4_decode_slice(AVCodecContext * avctx,const uint8_t * buffer,uint32_t size)97 static int nvdec_mpeg4_decode_slice(AVCodecContext *avctx, const uint8_t *buffer, uint32_t size)
98 {
99     return 0;
100 }
101 
nvdec_mpeg4_frame_params(AVCodecContext * avctx,AVBufferRef * hw_frames_ctx)102 static int nvdec_mpeg4_frame_params(AVCodecContext *avctx,
103                                   AVBufferRef *hw_frames_ctx)
104 {
105     // Each frame can at most have one P and one B reference
106     return ff_nvdec_frame_params(avctx, hw_frames_ctx, 2, 0);
107 }
108 
109 const AVHWAccel ff_mpeg4_nvdec_hwaccel = {
110     .name                 = "mpeg4_nvdec",
111     .type                 = AVMEDIA_TYPE_VIDEO,
112     .id                   = AV_CODEC_ID_MPEG4,
113     .pix_fmt              = AV_PIX_FMT_CUDA,
114     .start_frame          = nvdec_mpeg4_start_frame,
115     .end_frame            = ff_nvdec_simple_end_frame,
116     .decode_slice         = nvdec_mpeg4_decode_slice,
117     .frame_params         = nvdec_mpeg4_frame_params,
118     .init                 = ff_nvdec_decode_init,
119     .uninit               = ff_nvdec_decode_uninit,
120     .priv_data_size       = sizeof(NVDECContext),
121 };
122