Sinclair QL - raw2ql Sample Pictures

Where QL format images are provided, they are all in a ZIP file for spacesaving. You can open mode 4 files in mode 8, and vice versa, but they may look a bit odd. AND, don't forget to rename the files when unzipped. Each QL file should be 32,768 bytes exactly.

And while we're at it, all images are copyright. You are expressly forbidden from any copying, retransmission or modification of any images on this site at all. Sounds harsh but I'm only using the photo of the two young ladies for demo purposes - I'll do some proper test images soon-ish. Anyway, on with the show...

Full saturation colour spectrum A spectrum after conversion - The original was a perfectly smooth 24-bit rainbow. This shows off the wide range of colours that you can achieve
Greyscale ramp in 24-bit colour A grey ramp after conversion - This was saved as 24-bit colour, and you can see how each colour dithers differently
Greyscale ramp in 8-bit greyscale A grey ramp after conversion - This was saved as 8-bit grey, and you can see how it dithers as pure black and white
A photo intended for truecolour displays A photo intended for hi-res display after conversion - Note how the fine detail in the photo is lost by the built-in dithering process. You may prefer to posterize/dither images yourself, or at least increse the contrast a fair bit, to improve image clarity.
More to follow.

Previous Sample Images

For the simple reason that they're already on the server, I've left them there. These images relate more to the previous versions of raw2ql.

Mode 8 image
256x256
The pixels in the top-left & bottom-right were used in debugging to ensure the programs were doing it right.

Created in Photoshop.

A QL format "qltest.ql8" is available for testing your setup. [zip]

JPEG
256x256

This pic of me was used to test the mode 8 encoding. Note the vertical stretching.

From mode 8
256x256

I put the raw version of the above JPG through raw2ql8 and this is what came out. Note how raw2ql8 just thresholds each colour channel and we get this posterizing.

Mode 8 image
256x256
We've done the photoshop diffusion dithering now and the image contains only 8 colours. Stand a long way back and it's pretty close to the original

A QL format image "qpkcudd.ql8" is available. [zip]

Mode 8 image
256x256
Still had to be saved as 24bit raw, even though it's only a b/w diffusion dither. This kind of image looks excellent in mode 4, so...

Created in Photoshop.

GIF, 512x256

The image below is "qar.ql4" in the [zip] archive
Note the width stretching. This was saved as 24bit raw, but the blue channel was ignored on processing, so you get this on the QL (stretched, of course)...
Click on the thumbnail image for a big 139K GIF showing the original greyscale JPG (bottom-right), the colorized and curved version (top-left), the diffusion dithered one (bottom-left) and a QemuLator window showing the image (top-right).

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