How to export as PNG with 16 bit depth?

[derpybookshelf]

I need to export a PNG with 16 bit depth of the final image. The lowest I can get is 24 bit depth when exporting with 8bpc depth. I somehow managed to export a 16 bit PNG earlier but I can't remember how I did this. I've tried looking for an answer online but couldn't find one. I am using greyscale image mode with 16bit integer precision. Does anyone know how to export in 16 bit depth - maybe some kind of plugin is needed?

[Ofnuts]

(02-20-2024, 11:00 AM)derpybookshelf Wrote: I need to export a PNG with 16 bit depth of the final image. The lowest I can get is 24 bit depth when exporting with 8bpc depth. I somehow managed to export a 16 bit PNG earlier but I can't remember how I did this. I've tried looking for an answer online but couldn't find one. I am using greyscale image mode with 16bit integer precision. Does anyone know how to export in 16 bit depth - maybe some kind of plugin is needed?

AFAIK the only 16-bit/pixel format in PNG is a high precision grayscale without alpha (16bpc GRAY) , or a 8-bit precision grayscale with alpha (8bpc GRAYA).

[CmykStudent]

derpybookshelf: When you export to PNG, there should be an option for "Pixel Format". Change that from "automatic" to 16BPC and it should export correctly.

[derpybookshelf]

(02-20-2024, 12:29 PM)CmykStudent Wrote: derpybookshelf: When you export to PNG, there should be an option for "Pixel Format". Change that from "automatic" to 16BPC and it should export correctly.

I think I have misphrased the question - I'm not trying to export with 16 bit per colour (RGB) because then it is 16 bits R, 16 G, 16 B, for a total of 48 bits. I'm trying to export in a format such as 5-6-5 (5 bit R, 6 bit G, 5 bit B), for a total of 16.

[Ofnuts]

(02-20-2024, 12:51 PM)derpybookshelf Wrote:

(02-20-2024, 12:29 PM)CmykStudent Wrote: derpybookshelf: When you export to PNG, there should be an option for "Pixel Format". Change that from "automatic" to 16BPC and it should export correctly.

I think I have misphrased the question - I'm not trying to export with 16 bit per colour (RGB) because then it is 16 bits R, 16 G, 16 B, for a total of 48 bits. I'm trying to export in a format such as 5-6-5 (5 bit R, 6 bit G, 5 bit B), for a total of 16.

This isn't a PNG format,this is a BMP format.

   

[derpybookshelf]

(02-20-2024, 01:59 PM)Ofnuts Wrote:

(02-20-2024, 12:51 PM)derpybookshelf Wrote:

(02-20-2024, 12:29 PM)CmykStudent Wrote: derpybookshelf: When you export to PNG, there should be an option for "Pixel Format". Change that from "automatic" to 16BPC and it should export correctly.

I think I have misphrased the question - I'm not trying to export with 16 bit per colour (RGB) because then it is 16 bits R, 16 G, 16 B, for a total of 48 bits. I'm trying to export in a format such as 5-6-5 (5 bit R, 6 bit G, 5 bit B), for a total of 16.

This isn't a PNG format,this is a BMP format.

I managed to export it as PNG with 16 bit depth before, though I'm not sure how I did this. It needs to be PNG and not BMP.

[Ofnuts]

Sorry but this color encoding doesn't exist in the PNG format.

So either:

• Despite the PNG extension the file is a bitmap (same contents as a BMP file)
  
• This is a PNG file. Note that according to the Wikipedia description, the "bit depth" is the number of bits per channel, and not the total number of bits per pixel (color depth) which is 3 or 4 times greater in color images. So what you are showing would be a high precision PNG with 16 bit per channel (instead of the more common 8 bits) and if it is also 16-bits per pixel then it is grayscale without alpha.
  

You can use utilities such as mediainfo or ImageMagick's identify to have a more accurate description of the actual file format.