I am investigating the possibility of using IIPImage for serving images with transparency information.
JPEG format does not support alpha channel (opacity) but the alpha channel could be stored separately as a grayscale lossless TIFF (e.g. using Deflate). I presume this type of input data is supported by IIPImage.
However, also the output data need to be lossless grayscale and this leads me to my question: Is lossy JPEG the only output format or can I receive e.g. lossless PNG or lossless TIFF from the server?
The JPEG compression might do harm to the alpha channel mask because it contains sharp edges between black and white areas. I'd like to avoid this. Therefore the need for a lossless output format.
Thank you for your answer.
Matej.
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Hello,
I am investigating the possibility of using IIPImage for serving images with transparency information.
JPEG format does not support alpha channel (opacity) but the alpha channel could be stored separately as a grayscale lossless TIFF (e.g. using Deflate). I presume this type of input data is supported by IIPImage.
However, also the output data need to be lossless grayscale and this leads me to my question: Is lossy JPEG the only output format or can I receive e.g. lossless PNG or lossless TIFF from the server?
The JPEG compression might do harm to the alpha channel mask because it contains sharp edges between black and white areas. I'd like to avoid this. Therefore the need for a lossless output format.
Thank you for your answer.
Matej.
At the moment, the output is only JPEG, which does not support transparency. I do intend, however, to implement PNG output support in the future.
Thanks for the reply Ruven. I'll test with JPEGs at full quality meanwhile. See if that could do for the black&white masks.
Hi Ruven,
Just wanted to check if there is any update on PNG encoding.
Thanks,
Suhas
Sorry, still no PNG support. But it's still on the TODO list!