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Posted: **Sat Feb 13, 2016 1:42 am**

OK - Tiff is complicated. One potential issue is that a jpeg-like compression can be applied to a tif file. The likes of ImageMagick and LeadTools are using the C Tiff Library libtiff (core of which is tiffio.h, tiffio.c). It's a relatively old format, goes back to the days of Silicon Graphics (I used to love using the IRIX workstation for CAD).

Published by Adobe: The TIFF format defined TIFF6.pdf

Posted: **Sat Feb 13, 2016 7:39 am**

Strange and complicated, my friend...

First, my image examples work here (and should do that in Wales as well), maybe you can add two debug lines to check something...

Code: Select all

Case #ImageHeaderTIF_LSB
a=0
n=*Buffer\l[1]
Debug "Tif "+Str(n);   *** ADDED ***
If n>#ImageHeaderSize-#ImageHeaderSizeTif
: 
While m And n<#ImageHeaderSizeTif>>1
	Debug n;   *** ADDED ***
	:

You should see Tif 8 / 5 / 11 / 17 / 559 x 569 | P1170938.tif for my picture and something like Tif 810008 / 1 / 7 / 600 x 450 | Koala.tif for your examples.

Second, the TGA header seems to allow multiple values, didn't reread the format description but changed the code to allow also $00 (not only $01) now, so I get fine results for these type as well...

559 x 569 | P1170938.jpg
559 x 569 | P1170938.tga
559 x 569 | P1170938.tif
600 x 450 | Chrysanthemum.tga
600 x 450 | Chrysanthemum.tif
960 x 960 | Denzil Washington.jpg
600 x 450 | Desert.tga
600 x 450 | Desert.tif
600 x 450 | Hydrangeas.tga
600 x 450 | Hydrangeas.tif
:

Beside this I start to evaluate the image file type by checking the file extension now, because of the more "looser" header checks (e.g. $00/01 will only be checked for files with the extension TGA). Anyhow you should see correct values for all given images now, I have checked the procedure with ASCII and unicode option set for the compiler.

Code: Select all

Procedure.i CheckImageName(*Name)

	Enumeration
		#ImageTypeUnknown
		#ImageTypeJpg
		#ImageTypeJp2
		#ImageTypePng
		#ImageTypeBmp
		#ImageTypeTif
		#ImageTypePcx
		#ImageTypeGif
		#ImageTypeTga
	EndEnumeration

	Protected n

	n=FindString("|jpeg|jpg|jp2|png|bmp|tif|pcx|gif|tga|","|"+LCase(GetExtensionPart(PeekS(*Name)))+"|")
	If n>2
		n>>2
	ElseIf n=2
		n=1
	EndIf

	ProcedureReturn n

EndProcedure

Posted: **Sat Feb 13, 2016 1:58 pm**

Oh deary me! That Debug thing was such a great invention

The reason I got zero dimensions is because I never passed the full path of the files to GetImageInformation()

If ExamineDirectory(0,"C:\TempImagesTIF\MV\","*.*")
While NextDirectoryEntry(0)
If DirectoryEntryType(0)=#PB_DirectoryEntry_File
file.s = "C:\TempImagesTIF\MV\" + DirectoryEntryName(0)

I'm going to go away and hide in a corner for a while........

__________________________________________________
Code tags>quote tags
13.02.2016
RSBasic

Posted: **Sat Feb 13, 2016 4:04 pm**

I feel better now...
...because it looks like I am the only one who is doing strange things from time to time, especially when programming

Just one example (I know many more, but I don't want to talk about them), the CheckImageName procedure above contains the If n>2 : n>>2 : ElseIf n=2 : n=1 : EndIf statement which can be reduced to a much simpler If n>1 : n>>2 : EndIf, because the ElseIf will be needed at no time.

Posted: **Sat Feb 13, 2016 7:21 pm**

...RS Basic, I deliberately omitted the code tags so that I could use colour to highlight where the error was! Your change to my post makes it less useful!

Posted: **Sat Feb 13, 2016 7:35 pm**

@IdeasVacuum
I'm sorry, you're right.

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