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+ "*.tif" ,
19+ } ;
20+
21+ public ImageSequenceImporter ( string directoryPath )
22+ {
23+ this . directoryPath = directoryPath ;
24+ }
25+
26+ public override VolumeDataset Import ( )
27+ {
28+ if ( ! Directory . Exists ( directoryPath ) )
29+ throw new NullReferenceException ( "No directory found: " + directoryPath ) ;
30+
31+ List < string > imagePaths = GetSortedImagePaths ( ) ;
32+
33+ if ( ! ImageSetHasUniformDimensions ( imagePaths ) )
34+ throw new IndexOutOfRangeException ( "Image sequence has non-uniform dimensions" ) ;
35+
36+ Vector3Int dimensions = GetVolumeDimensions ( imagePaths ) ;
37+ int [ ] data = FillSequentialData ( dimensions , imagePaths ) ;
38+ VolumeDataset dataset = FillVolumeDataset ( data , dimensions ) ;
39+
40+ return dataset ;
41+ }
42+
43+ /// <summary>
44+ /// Gets every file path in the directory with a supported suffix.
45+ /// </summary>
46+ /// /// <returns>A sorted list of image file paths.</returns>
47+ private List < string > GetSortedImagePaths ( )
48+ {
49+ var imagePaths = new List < string > ( ) ;
50+
51+ foreach ( var type in supportedImageTypes )
52+ {
53+ imagePaths . AddRange ( Directory . GetFiles ( directoryPath , type ) ) ;
54+ }
55+
56+ imagePaths . Sort ( ) ;
57+
58+ return imagePaths ;
59+ }
60+
61+ /// <summary>
62+ /// Checks if every image in the set has the same XY dimensions.
63+ /// </summary>
64+ /// <param name="imagePaths">The list of image paths to check.</param>
65+ /// <returns>True if at least one image differs from another.</returns>
66+ private bool ImageSetHasUniformDimensions ( List < string > imagePaths )
67+ {
68+ bool hasUniformDimension = true ;
69+
70+ Vector2Int previous , current ;
71+ previous = GetImageDimensions ( imagePaths [ 0 ] ) ;
72+
73+ foreach ( var path in imagePaths )
74+ {
75+ current = GetImageDimensions ( path ) ;
76+
77+ if ( current . x != previous . x || current . y != previous . y )
78+ {
79+ hasUniformDimension = false ;
80+ break ;
81+ }
82+
83+ previous = current ;
84+ }
85+
86+ return hasUniformDimension ;
87+ }
88+
89+ /// <summary>
90+ /// Gets the XY dimensions of an image at the path.
91+ /// </summary>
92+ /// <param name="path">The image path to check.</param>
93+ /// <returns>The XY dimensions of the image.</returns>
94+ private Vector2Int GetImageDimensions ( string path )
95+ {
96+ byte [ ] bytes = File . ReadAllBytes ( path ) ;
97+
98+ Texture2D texture = new Texture2D ( 1 , 1 ) ;
99+ texture . LoadImage ( bytes ) ;
100+
101+ Vector2Int dimensions = new Vector2Int ( )
102+ {
103+ x = texture . width ,
104+ y = texture . height
105+ } ;
106+
107+ return dimensions ;
108+ }
109+
110+ /// <summary>
111+ /// Adds a depth value Z to the XY dimensions of the first image.
112+ /// </summary>
113+ /// <param name="paths">The set of image paths comprising the volume.</param>
114+ /// <returns>The dimensions of the volume.</returns>
115+ private Vector3Int GetVolumeDimensions ( List < string > paths )
116+ {
117+ Vector2Int twoDimensional = GetImageDimensions ( paths [ 0 ] ) ;
118+ Vector3Int threeDimensional = new Vector3Int ( )
119+ {
120+ x = twoDimensional . x ,
121+ y = twoDimensional . y ,
122+ z = paths . Count
123+ } ;
124+ return threeDimensional ;
125+ }
126+
127+ /// <summary>
128+ /// Converts a volume set of images into a sequential series of values.
129+ /// </summary>
130+ /// <param name="dimensions">The XYZ dimensions of the volume.</param>
131+ /// <param name="paths">The set of image paths comprising the volume.</param>
132+ /// <returns>The set of sequential values for the volume.</returns>
133+ private int [ ] FillSequentialData ( Vector3Int dimensions , List < string > paths )
134+ {
135+ var data = new List < int > ( dimensions . x * dimensions . y * dimensions . z ) ;
136+ var texture = new Texture2D ( 1 , 1 ) ;
137+
138+ foreach ( var path in paths )
139+ {
140+ byte [ ] bytes = File . ReadAllBytes ( path ) ;
141+ texture . LoadImage ( bytes ) ;
142+
143+ Color [ ] pixels = texture . GetPixels ( ) ; // Order priority: X -> Y -> Z
144+ int [ ] imageData = DensityHelper . ConvertColorsToDensities ( pixels ) ;
145+
146+ data . AddRange ( imageData ) ;
147+ }
148+
149+ return data . ToArray ( ) ;
150+ }
151+
152+ /// <summary>
153+ /// Wraps volume data into a VolumeDataset.
154+ /// </summary>
155+ /// <param name="data">Sequential value data for a volume.</param>
156+ /// <param name="dimensions">The XYZ dimensions of the volume.</param>
157+ /// <returns>The wrapped volume data.</returns>
158+ private VolumeDataset FillVolumeDataset ( int [ ] data , Vector3Int dimensions )
159+ {
160+ string name = Path . GetFileName ( directoryPath ) ;
161+
162+ VolumeDataset dataset = new VolumeDataset ( )
163+ {
164+ name = name ,
165+ datasetName = name ,
166+ data = data ,
167+ dimX = dimensions . x ,
168+ dimY = dimensions . y ,
169+ dimZ = dimensions . z ,
170+ scaleX = 1f , // Scale arbitrarily normalised around the x-axis
171+ scaleY = ( float ) dimensions . y / ( float ) dimensions . x ,
172+ scaleZ = ( float ) dimensions . z / ( float ) dimensions . x
173+ } ;
174+
175+ return dataset ;
176+ }
177+ }
178+ }
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