[gdal-dev] Get real and turf imaginary from complex float...

[Derek Mueller]

Thanks again Frank,

That's actually very straightforward and works well.

Derek

Frank Warmerdam wrote:
>> I tried to import the CFloat32 directly into IDL/ENVI but it doesn't 
>> like the '64-bit pixel'.  Could there be a workaround by modifying 
>> tiff tags to say the CFloat32 data are actually 2 separate 32-bit 
>> numbers?
>
> There is no mechanism to do this in TIFF, but you might find you can
> export to a raw format and then alter the raw header to describe the
> raw file differently.
>
> The only raw format driver I can find that supports complex imagery is
> the MFF2 (aka HKV) format.
>
> If I translate a CInt16 dataset to MFF2 format (which creates a 
> directory)
> I get an attrib file that looks like:
>
> channel.enumeration = 1
> channel.interleave = { *pixel tile sequential }
> extent.cols = 2500
> extent.rows = 14795
> pixel.encoding = { unsigned *twos-complement ieee-754 }
> pixel.size = 32
> pixel.field = { real *complex }
> pixel.order = { *lsbf msbf }
> version = 1.1
>
> If I change this to look like:
>
> channel.enumeration = 2
> channel.interleave = { *pixel tile sequential }
> extent.cols = 2500
> extent.rows = 14795
> pixel.encoding = { unsigned *twos-complement ieee-754 }
> pixel.size = 16
> pixel.field = { *real complex }
> pixel.order = { *lsbf msbf }
> version = 1.1
>
> The the dataset is essentially treated as two Int16 bands.
> Note that channel.enumeration was changed to 2, pixel.size was
> changed from 32 to 16, and pixel.field now has the star by real
> instead of complex.
>
> Best regards,