#7 file layers conversion

[ekoprogger]

Dear suppport team,

we are currently using JCGM to convert a CGM file into various other formats (TIFF, JPG, PNG ...).
While the conversion is successful, it seems that not all of the original file's layers are
converted and left out in the target file.
Is there any way to control which CGM-layers are converted and which are not?
In our case, we are looking for a way to convert all available layers.

Best regards and thanks for your help

The eko crowd

[Philippe Cadé]

It looks like the animals are drawn using a bitonal tile and T6 compression.

Unfortunately, T6 is currently unsupported (cf. TileElement.readSdrAndBitStream).

[ekoprogger]

Dear Philippe,
thank you for your reply. Could you give us some more information as to how your application works and how we would have to alter/enhance your code to support the T6 compression format?

Currently we are using international standard ISO/IEC 8632-3 Part 3 for our CGMs.

here we go:
Element Class 4 / Element ID 28|29 are defined by 6 parameters.
If I got you correctly, you did not implement P6(bitstream) compressed cell colour specifiers (by checking the source code).

In TileElement.readSdrAndBitStream only bitmaps in uncompressed format are used (which is defined by parameter 1).

Would that be the place for me to start and insert the code needed to make use of T6?

That is currently the primary and most important question to me.

On a side note - does the command class already provide the bitstream needed for the conversion or do I have to get that
information in a different way (e.g. checking byte by byte)?

It would be great if you can provide some deeper insight and support in that regard.

Best regards and thanks in advance

The eko crowd

[Philippe Cadé]

This is now corrected in version 0.3.0 of jcgm-core. You will need an ImageIO plugin which is able to render TIFF files with T6 compression, such as https://github.com/jai-imageio/jai-imageio-core

Please note that I am moving jcgm to GitHub, the new release is available here: https://github.com/SwissAS/jcgm-core/