2008.09.23 16:24 "[Tiff] New to list, with a query on TIFFTAG_GDAL_METADATA", by David J Taylor

2008.10.22 23:31 "Re: [Tiff] JPEGSetupEncode messages", by Raphaël_Lemoine

Hello,

On Oct 23, 2008, at 1:16 AM, Frank Warmerdam wrote:

> Jeffrey Ratcliffe wrote:

>> I have tiff output from a scanner with which I would like use >> libtiff's jpeg compression via tiffcp. For a greyscale scan, however,

>> I am getting:
>> JPEGSetupEncode: RowsPerStrip must be multiple of 8 for JPEG
>
> Jeff,
>
> I would suggest selecting a RowsPerStrip value that is a multiple
> of 8.
>
>> and for colour scans:
>> JPEGSetupEncode: BitsPerSample 16 not allowed for JPEG
>> What can I do to make this work?
>

> It is quite challenging to manage 16bit data with JPEG compression. > How badly do you want to do this?

>

AFAIK, there is no such thing as 16-bits per channels in the JPEG standard (only 8 and 12 bits are allowed).

With the IJG library, this can only be selected at compile time...

Best regards,

Raphael

Best regards,
--

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