'枚举图片格式种类
Public Enum ImageForm
   [BMP] = 0
   [JPEG] = 1
   [GIF87] = 2
   [GIF89] = 3
   [PNG] = 4
   [TGA Normal] = 5 'TGA未压缩
   [TGA RLE] = 6     'TGA经过RLE压缩后的
   [PCX] = 7
   [TIFF] = 8
   [ICO] = 9
   [CUR] = 10
   [IFF] = 11
   [ANI] = 12
   [Other] = 13
   [FileError] = 14
End Enum



'-----------------------------------------------------------------------
'-----------------------------------------------------------------------
'--   标题：获取图片的格式
'--   作者：BEAR-BEN
'--   制作日期：2007-8-5
'--   支持的格式：BMP,JPEG,GIF,PNG,TGA,PCX,TIFF,
'                             ICO,CUR,IFF,ANI 共11种格式
'--   版本：1.0
'--   使用者请保留版权，谢谢！
'-----------------------------------------------------------------------
'-----------------------------------------------------------------------
Public Function GetImageFileForm(ImageFilePath As String) As ImageForm
Dim FileHeader(5) As Byte, FileNumber As Integer

   GetImageFileForm = FileError

   If Dir(ImageFilePath) <> "" Then    '判断图片文件是否存在
     FileNumber = FreeFile
     Open ImageFilePath For Binary As #FileNumber
       Get FileNumber, , FileHeader()   '二进制流读取图片前5个字符
     Close FileNumber
    
     GetImageFileForm = Other
    
    
    '文件头标识识别
     If (FileHeader(0) = 66) And (FileHeader(1) = 77) Then
       GetImageFileForm = BMP 
       Exit Function
     End If
     If (FileHeader(0) = 255) And (FileHeader(1) = 216) Then
       GetImageFileForm = JPEG    
       Exit Function
     End If
     If (FileHeader(0) = 71) And (FileHeader(1) = 73) And (FileHeader(2) = 70) And (FileHeader(4) = 57) Then
       GetImageFileForm = GIF89
       Exit Function
     End If
     If (FileHeader(0) = 71) And (FileHeader(1) = 73) And (FileHeader(2) = 70) And (FileHeader(4) = 55) Then
       GetImageFileForm = GIF87
       Exit Function
     End If
     If (FileHeader(0) = 137) And (FileHeader(1) = 80) Then
       GetImageFileForm = PNG  
       Exit Function
     End If
     If (FileHeader(0) = 73) And (FileHeader(1) = 73) Then
       GetImageFileForm = TIFF  'TIFF 摩托罗拉
       Exit Function
     End If
     If (FileHeader(0) = 77) And (FileHeader(1) = 77) Then
       GetImageFileForm = TIFF  'TIFF Intel
       Exit Function
     End If
     If (FileHeader(2) = 1) And (FileHeader(4) = 1) Then
       GetImageFileForm = ICO 
       Exit Function
     End If
     If (FileHeader(2) = 2) And (FileHeader(4) = 1) Then
       GetImageFileForm = CUR 
       Exit Function
     End If
     If (FileHeader(0) = 82) And (FileHeader(1) = 73) And (FileHeader(2) = 70) And (FileHeader(3) = 70) Then
       GetImageFileForm = ANI  
       Exit Function
     End If
     If (FileHeader(2) = 2) And (FileHeader(4) = 0) Then
       GetImageFileForm = [TGA Normal]
       Exit Function
     End If
     If (FileHeader(2) = 16) And (FileHeader(4) = 0) Then
       GetImageFileForm = [TGA RLE]
       Exit Function
     End If
     If (FileHeader(0) = 10) Then
       GetImageFileForm = PCX 
       Exit Function
     End If
   End If
End Function
//delphi/8991