1+ using System ;
2+ using System . Collections . Generic ;
3+ using System . IO ;
4+ using UnityEngine ;
5+
6+ namespace UnityVolumeRendering
7+ {
8+ /// <summary>
9+ /// Converts a directory of image slices into a VolumeDataset for volumetric rendering.
10+ /// </summary>
11+ public class ImageSequenceImporter : DatasetImporterBase
12+ {
13+ private string directoryPath ;
14+ private string [ ] supportedImageTypes = new string [ ]
15+ {
16+ "*.png" ,
17+ "*.jpg" ,
18+ } ;
19+
20+ public ImageSequenceImporter ( string directoryPath )
21+ {
22+ this . directoryPath = directoryPath ;
23+ }
24+
25+ public override VolumeDataset Import ( )
26+ {
27+ if ( ! Directory . Exists ( directoryPath ) )
28+ throw new NullReferenceException ( "No directory found: " + directoryPath ) ;
29+
30+ List < string > imagePaths = GetSortedImagePaths ( ) ;
31+
32+ if ( ! ImageSetHasUniformDimensions ( imagePaths ) )
33+ throw new IndexOutOfRangeException ( "Image sequence has non-uniform dimensions" ) ;
34+
35+ Vector3Int dimensions = GetVolumeDimensions ( imagePaths ) ;
36+ int [ ] data = FillSequentialData ( dimensions , imagePaths ) ;
37+ VolumeDataset dataset = FillVolumeDataset ( data , dimensions ) ;
38+
39+ return dataset ;
40+ }
41+
42+ /// <summary>
43+ /// Gets every file path in the directory with a supported suffix.
44+ /// </summary>
45+ /// /// <returns>A sorted list of image file paths.</returns>
46+ private List < string > GetSortedImagePaths ( )
47+ {
48+ var imagePaths = new List < string > ( ) ;
49+
50+ foreach ( var type in supportedImageTypes )
51+ {
52+ imagePaths . AddRange ( Directory . GetFiles ( directoryPath , type ) ) ;
53+ }
54+
55+ imagePaths . Sort ( ) ;
56+
57+ return imagePaths ;
58+ }
59+
60+ /// <summary>
61+ /// Checks if every image in the set has the same XY dimensions.
62+ /// </summary>
63+ /// <param name="imagePaths">The list of image paths to check.</param>
64+ /// <returns>True if at least one image differs from another.</returns>
65+ private bool ImageSetHasUniformDimensions ( List < string > imagePaths )
66+ {
67+ bool hasUniformDimension = true ;
68+
69+ Vector2Int previous , current ;
70+ previous = GetImageDimensions ( imagePaths [ 0 ] ) ;
71+
72+ foreach ( var path in imagePaths )
73+ {
74+ current = GetImageDimensions ( path ) ;
75+
76+ if ( current . x != previous . x || current . y != previous . y )
77+ {
78+ hasUniformDimension = false ;
79+ break ;
80+ }
81+
82+ previous = current ;
83+ }
84+
85+ return hasUniformDimension ;
86+ }
87+
88+ /// <summary>
89+ /// Gets the XY dimensions of an image at the path.
90+ /// </summary>
91+ /// <param name="path">The image path to check.</param>
92+ /// <returns>The XY dimensions of the image.</returns>
93+ private Vector2Int GetImageDimensions ( string path )
94+ {
95+ byte [ ] bytes = File . ReadAllBytes ( path ) ;
96+
97+ Texture2D texture = new Texture2D ( 1 , 1 ) ;
98+ texture . LoadImage ( bytes ) ;
99+
100+ Vector2Int dimensions = new Vector2Int ( )
101+ {
102+ x = texture . width ,
103+ y = texture . height
104+ } ;
105+
106+ return dimensions ;
107+ }
108+
109+ /// <summary>
110+ /// Adds a depth value Z to the XY dimensions of the first image.
111+ /// </summary>
112+ /// <param name="paths">The set of image paths comprising the volume.</param>
113+ /// <returns>The dimensions of the volume.</returns>
114+ private Vector3Int GetVolumeDimensions ( List < string > paths )
115+ {
116+ Vector2Int twoDimensional = GetImageDimensions ( paths [ 0 ] ) ;
117+ Vector3Int threeDimensional = new Vector3Int ( )
118+ {
119+ x = twoDimensional . x ,
120+ y = twoDimensional . y ,
121+ z = paths . Count
122+ } ;
123+ return threeDimensional ;
124+ }
125+
126+ /// <summary>
127+ /// Converts a volume set of images into a sequential series of values.
128+ /// </summary>
129+ /// <param name="dimensions">The XYZ dimensions of the volume.</param>
130+ /// <param name="paths">The set of image paths comprising the volume.</param>
131+ /// <returns>The set of sequential values for the volume.</returns>
132+ private int [ ] FillSequentialData ( Vector3Int dimensions , List < string > paths )
133+ {
134+ var data = new List < int > ( dimensions . x * dimensions . y * dimensions . z ) ;
135+ var texture = new Texture2D ( 1 , 1 ) ;
136+
137+ foreach ( var path in paths )
138+ {
139+ byte [ ] bytes = File . ReadAllBytes ( path ) ;
140+ texture . LoadImage ( bytes ) ;
141+
142+ Color [ ] pixels = texture . GetPixels ( ) ; // Order priority: X -> Y -> Z
143+ int [ ] imageData = DensityHelper . ConvertColorsToDensities ( pixels ) ;
144+
145+ data . AddRange ( imageData ) ;
146+ }
147+
148+ return data . ToArray ( ) ;
149+ }
150+
151+ /// <summary>
152+ /// Wraps volume data into a VolumeDataset.
153+ /// </summary>
154+ /// <param name="data">Sequential value data for a volume.</param>
155+ /// <param name="dimensions">The XYZ dimensions of the volume.</param>
156+ /// <returns>The wrapped volume data.</returns>
157+ private VolumeDataset FillVolumeDataset ( int [ ] data , Vector3Int dimensions )
158+ {
159+ string name = Path . GetFileName ( directoryPath ) ;
160+
161+ VolumeDataset dataset = new VolumeDataset ( )
162+ {
163+ name = name ,
164+ datasetName = name ,
165+ data = data ,
166+ dimX = dimensions . x ,
167+ dimY = dimensions . y ,
168+ dimZ = dimensions . z ,
169+ scaleX = 1f , // Scale arbitrarily normalised around the x-axis
170+ scaleY = ( float ) dimensions . y / ( float ) dimensions . x ,
171+ scaleZ = ( float ) dimensions . z / ( float ) dimensions . x
172+ } ;
173+
174+ return dataset ;
175+ }
176+ }
177+ }
0 commit comments