1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
|
// Copyright 2016 The Draco Authors.
//
// Licensed under the Apache License, Version 2.0 (the "License");
// you may not use this file except in compliance with the License.
// You may obtain a copy of the License at
//
// http://www.apache.org/licenses/LICENSE-2.0
//
// Unless required by applicable law or agreed to in writing, software
// distributed under the License is distributed on an "AS IS" BASIS,
// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
// See the License for the specific language governing permissions and
// limitations under the License.
//
#include "draco/compression/attributes/prediction_schemes/prediction_scheme_encoder_factory.h"
namespace draco {
PredictionSchemeMethod SelectPredictionMethod(
int att_id, const PointCloudEncoder *encoder) {
if (encoder->options()->GetSpeed() >= 10) {
// Selected fastest, though still doing some compression.
return PREDICTION_DIFFERENCE;
}
if (encoder->GetGeometryType() == TRIANGULAR_MESH) {
// Use speed setting to select the best encoding method.
const PointAttribute *const att = encoder->point_cloud()->attribute(att_id);
if (att->attribute_type() == GeometryAttribute::TEX_COORD) {
if (encoder->options()->GetSpeed() < 4) {
// Use texture coordinate prediction for speeds 0, 1, 2, 3.
return MESH_PREDICTION_TEX_COORDS_PORTABLE;
}
}
if (att->attribute_type() == GeometryAttribute::NORMAL) {
#ifdef DRACO_NORMAL_ENCODING_SUPPORTED
if (encoder->options()->GetSpeed() < 4) {
// Use geometric normal prediction for speeds 0, 1, 2, 3.
return MESH_PREDICTION_GEOMETRIC_NORMAL;
}
#endif
return PREDICTION_DIFFERENCE; // default
}
// Handle other attribute types.
if (encoder->options()->GetSpeed() >= 8) {
return PREDICTION_DIFFERENCE;
}
if (encoder->options()->GetSpeed() >= 2 ||
encoder->point_cloud()->num_points() < 40) {
// Parallelogram prediction is used for speeds 2 - 7 or when the overhead
// of using constrained multi-parallelogram would be too high.
return MESH_PREDICTION_PARALLELOGRAM;
}
// Multi-parallelogram is used for speeds 0, 1.
return MESH_PREDICTION_CONSTRAINED_MULTI_PARALLELOGRAM;
}
// Default option is delta coding.
return PREDICTION_DIFFERENCE;
}
// Returns the preferred prediction scheme based on the encoder options.
PredictionSchemeMethod GetPredictionMethodFromOptions(
int att_id, const EncoderOptions &options) {
const int pred_type =
options.GetAttributeInt(att_id, "prediction_scheme", -1);
if (pred_type == -1) {
return PREDICTION_UNDEFINED;
}
if (pred_type < 0 || pred_type >= NUM_PREDICTION_SCHEMES) {
return PREDICTION_NONE;
}
return static_cast<PredictionSchemeMethod>(pred_type);
}
} // namespace draco
|
