Convert from PNG to TIFF

[pablobhz]

Hello.
It will be better if i explain my process from the beginning.

I'm reading a file, that contains TIFF data. TIFF Header is 240 bytes - the header is like an default for any file, but some bytes (width, height, stripbytecounts) are replaced with its respective data on the process of the TIFF creation. In the end i get my TIFF file perfectly, no problems, conversion sucessfull.

Then, using ImageMagick, i convert this TIFF to a PNG. No problems so far, conversion goes okay using ImageMagick .NET Package.

However, i would like to use ImageMagick for converting a file from PNG to TIFF ; i did some tests here, and , ImageMagick just adds some bytes to the file but not the TIFF data. I know because i converted a file from TIFF to PNG here (one of my own), and when converting from PNG to TIFF , the TIFF file was way small than the original one.

TIFF File after i extract\create: 200k
PNG file i convert using ImageMagick: 40k
TIFF file i convert usinge ImageMagick: 45k

Seems like a lot of data has been lost ; and, i would like to know if there's any parameter or anything else i can do to get this information back.
Its easy to keep the TIFF file if i'm the one who owns the file with the TIFF data ; however, if i just receive a PNG file, i would like to convert it to TIFF and get its data back.

Is there any way to do that ? Anything i might try ?

Thanks !

[snibgo]

Perhaps different compression is used. I doubt that any significant data is lost. If you put sample files online, someone can take a look.

You should also say what version of IM you are using, on what platform.

[fmw42]

The data could be xmp profile data that was remove or other metatags that get lost going from TIFF to PNG