[bmx] PNG Header by FlameDuck [ 1+ years ago ]

[BlitzBot]

Title : PNG Header
Author : FlameDuck
Posted : 1+ years ago

Description : Provides methods to determine if a given file is a PNG file, and which dimensions it has without loading the entire file into memory.

Code :

Code: BlitzMax

1. Strict
2.  
3. Import BRL.Stream
4. Import BRL.EndianStream
5.  
6. Type PNGHeader
7.  
8.         Field signiture:String
9.         Field chunksize:Int
10.         Field chunkID:String
11.         Field width:Int
12.         Field height:Int
13.         Const PNG_ID:String = Chr($89) + Chr($50) + Chr($4E) + Chr($47) + Chr($0D) + Chr($0A) + Chr($1A) + Chr($0A)
14.  
15.         Function fromFile:PNGHeader( url:Object )
16.                 Local myStream:TStream = ReadStream( url )
17.                 Local temp:PNGHeader
18.                 If StreamSize (myStream) > 24
19.                         temp = New PNGHeader
20.                         Local eStream:TStream = BigEndianStream(myStream)
21.                         temp.signiture = ReadString (eStream , 8)
22.                         temp.chunksize = Readint (eStream)
23.                         temp.chunkID = ReadString (eStream , 4)
24.                         temp.width = Readint (eStream)
25.                         temp.height = Readint (eStream)
26.                         CloseStream eStream
27.                 EndIf
28.                 CloseStream myStream
29.                 Return temp
30.         EndFunction    
31.  
32.         Method isPNG:Int()
33.                 If signiture = PNG_ID
34.                         Return True
35.                 EndIf
36.                 Return False
37.         EndMethod
38.        
39.         Method toString:String()
40.                 Local temp:String = "isPng: "
41.                 If isPNG()
42.                         temp:+"True "
43.                 Else
44.                         temp:+"False "
45.                 EndIf
46.                 temp:+"Width: " + width + " Height: " + height
47.                
48.                 Return temp
49.         EndMethod
50. EndType

Comments :


VP(Posted 1+ years ago)

 This would be for max, rather than b3d


VP(Posted 1+ years ago)

 Ignore me, I've got a cold.