FreeImage
Documentation
FreeImage is an Open Source library project for developers who would like to support popular graphics image formats like PNG, BMP, JPEG, TIFF and others as needed by today's multimedia applications. FreeImage is easy to use, fast, multithreading safe, compatible with all 32-bit versions of Windows, and cross-platform (works both with Linux and Mac OS X).Website: http://freeimage.sourceforge.net/
Platforms supported: Win32, Linux
Headers to include: FreeImage.bi
Header version: 3.15.1
Example included: yes, in examples/files/FreeImage
Example
Here follows an example of using FreeImage in FreeBASIC. If using Windows you will require freeimage.dll which is available from the FreeImage site.
'' Code example for loading all common image types using FreeImage.
'' The example loads an image passed as a command line argument.
'' The function FI_Load returns a null pointer (0) if there was an error during
'' loading. Otherwise it returns a 32-bit PUT compatible buffer.
#include "FreeImage.bi"
#include "crt.bi"
#include "fbgfx.bi"
Function FI_Load(filename As String) As Any Ptr
If Len(filename) = 0 Then
Return NULL
End If
'' Find out the image format
Dim As FREE_IMAGE_FORMAT form = FreeImage_GetFileType(StrPtr(filename), 0)
If form = FIF_UNKNOWN Then
form = FreeImage_GetFIFFromFilename(StrPtr(filename))
End If
'' Exit if unknown
If form = FIF_UNKNOWN Then
Return NULL
End If
'' Always load jpegs accurately
Dim As UInteger flags = 0
If form = FIF_JPEG Then
flags = JPEG_ACCURATE
End If
'' Load the image into memory
Dim As FIBITMAP Ptr image = FreeImage_Load(form, StrPtr(filename), flags)
If image = NULL Then
'' FreeImage failed to read in the image
Return NULL
End If
'' Flip the image so it matches FB's coordinate system
FreeImage_FlipVertical(image)
'' Convert to 32 bits per pixel
Dim As FIBITMAP Ptr image32 = FreeImage_ConvertTo32Bits(image)
'' Get the image's size
Dim As UInteger w = FreeImage_GetWidth(image)
Dim As UInteger h = FreeImage_GetHeight(image)
'' Create an FB image of the same size
Dim As fb.Image Ptr sprite = ImageCreate(w, h)
Dim As Byte Ptr target = CPtr(Byte Ptr, sprite + 1)
Dim As Integer target_pitch = sprite->pitch
Dim As Any Ptr source = FreeImage_GetBits(image32)
Dim As Integer source_pitch = FreeImage_GetPitch(image32)
'' And copy over the pixels, row by row
For y As Integer = 0 To (h - 1)
memcpy(target + (y * target_pitch), _
source + (y * source_pitch), _
w * 4)
Next
FreeImage_Unload(image32)
FreeImage_Unload(image)
Return sprite
End Function
ScreenRes 640, 480, 32
Dim As String filename = Command(1)
Dim As Any Ptr image = FI_Load(filename)
If image <> 0 Then
Put (0, 0), image
ImageDestroy(image)
Else
Print "Problem while loading file : " & filename
End If
Sleep