Save as Tiff : LZW

[mattewan]

Hello,

I know this question has been asked before but im also getting the same problem.

Basically, im opening an image, then drawing another image into the first image, then trying to save it as group4 tiff, but i always get lzw.

Here is the code im using:

to insert image:

Code: Select all

imaging.DrawGdPictureImage(TempImage, ImageID, LeftPos, TopPos, pWidth, pHeight, GdPicture.InterpolationMode.InterpolationModeDefault)

to save:

Code: Select all

imaging.SaveAsTIFF(ImageID, OutputFile, GdPicture.TiffCompression.TiffCompressionCCITT4)

The original Image is group4, and the image im inserting into the document is group 4, but when i save, its a colour lzw:
LZW,1 Row per strip, 24Bpp, 200dpi

I have tried both 6.2.9 & 6.2.10 both do the same thing

Am i doing something wrong or is this a bug

Thank you

[Loïc]

Hi,

CCITT4 & CCITT3 compression schemes are designed for bitonal image only.

After the call to DrawGdPictureImage() your image is converted to true color. So, just convert your image to 1bpp before saving it as TIFF.

IE:

Code: Select all

Imaging.ConvertTo1Bpp(ImageID)
imaging.SaveAsTIFF(ImageID, OutputFile, GdPicture.TiffCompression.TiffCompressionCCITT4)

Hope this helps.

Loïc