Hi,
I have noticed many of the images are very black and white, not very subtle, although some are allright. My way to produce better looking images is to use a macOS-based tool called HyperDither, which is based on Bill Atkinson's ancient original Macintosh rendering algorithm.
This gives great results, in my opinion. For example, the image bounds-union.bmp looks far better than the one pre-installed on the calculators, IMHO.
Converting the PNG to a 1-bit BMP turned out to be something of a challenge, I ended up using ImageMagick (Homebrew installation), this works fine, once you get the hang of it. Anyway, I include a few examples of images I made using this method, maybe interesting for other users, or helpful, etcetera. Regards!
A better way to produce 400x240 1-bit images
Forum rules
Do you have a creative streak? Post your OFFIMG photos here.
Images MUST be in Windows-NT .bmp format at a resolution of 400x240 pixels and 1-bit colour depth or they will not be displayed by the DM42. Images that do not meet this requirement will be removed from the forum
Do you have a creative streak? Post your OFFIMG photos here.
Images MUST be in Windows-NT .bmp format at a resolution of 400x240 pixels and 1-bit colour depth or they will not be displayed by the DM42. Images that do not meet this requirement will be removed from the forum
A better way to produce 400x240 1-bit images
- Attachments
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- bounds-union.bmp (12.25 KiB) Viewed 4407 times
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- magic-cap.bmp (12.25 KiB) Viewed 4407 times
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- stuwdriel.bmp (12.25 KiB) Viewed 4407 times
Robbert Jan, MSEE, RPN user since 1976 and a collector for many years I now own all the important ones: HP-35, 45, 55, 65, 97, 19, 21, 25, 34, 10-16, 41, 42, 71, 48, 50, Prime, DM41, DM42, WP43, C47, R47; Project 47 team member https://47calc.com
Re: A better way to produce 400x240 1-bit images
Thd Driel photo is great, I loved to wander there when I was living in Arnhem. The stew is also called the faucet of the Netherlands.
DM41X beta: SN00018.
DM41X: SN00496.
DM42 beta: SN00074.
DM42:SN06020.
DM42 converted to C47 SN08973
DM10L: SN056/100.
DM11L: SN 02058.
DM15L: SN2074.
DM16L: SN2156.
DM15, DM16, DM41
and a whole bunch of the original HP's,
DM41X: SN00496.
DM42 beta: SN00074.
DM42:SN06020.
DM42 converted to C47 SN08973
DM10L: SN056/100.
DM11L: SN 02058.
DM15L: SN2074.
DM16L: SN2156.
DM15, DM16, DM41
and a whole bunch of the original HP's,
Re: A better way to produce 400x240 1-bit images
Thanks, the stuw-driel is based on my own photograph.
Robbert Jan, MSEE, RPN user since 1976 and a collector for many years I now own all the important ones: HP-35, 45, 55, 65, 97, 19, 21, 25, 34, 10-16, 41, 42, 71, 48, 50, Prime, DM41, DM42, WP43, C47, R47; Project 47 team member https://47calc.com
Re: A better way to produce 400x240 1-bit images
I use GIMP (picture/modus/indexed/use 1 bit palette), there are a few colour approximation methods but no real dithering as far as I can see.
HP41C (2x), HP41CV, HP41CX, DM41X β, DM41X, DM42, HP11C, HP48G, HP97
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Re: A better way to produce 400x240 1-bit images
Nice picture! It looked familiar even though I've never been to Driel, but it turns out that the ones at Amerongen and Hagestein look exactly the same. I must have visited the one at Amerongen on a high school field trip.
(Note: The English word for "stuw" is "weir.")
Re: A better way to produce 400x240 1-bit images
Yes. Resize (Scale) the image first then "Image/Mode/Indexed.../Use black and white (1-bit) palette" But, as you say. no obvious dithering. Thanks though.
Re: A better way to produce 400x240 1-bit images
These weirs are new to me, very cool. I've just perused about 50 photos of these, they are certainly well-photographed and it appears they are frequent tourist and sight-seeing targets. Is there some special history behind them, I've never seen anything like these.Thomas Okken wrote: ↑Sun Jun 20, 2021 11:28 pmNice picture! It looked familiar even though I've never been to Driel, but it turns out that the ones at Amerongen and Hagestein look exactly the same. I must have visited the one at Amerongen on a high school field trip.
(Note: The English word for "stuw" is "weir.")
Thanks for sharing these notes, very interesting.
--bob p
DM42: β00071 & 00282, DM41X: β00071 & 00656, DM10L: 071/100
DM42: β00071 & 00282, DM41X: β00071 & 00656, DM10L: 071/100
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Re: A better way to produce 400x240 1-bit images
The reason for these is to maintain a more or less constant water level along the length of the lower Rhine. The water flow through the Rhine is very seasonal, because of the effect of snow melting in the Alps in spring and because of seasonal variations in rainfall in the upper watershed.
Thanks to the weirs, the water level can be kept high even when there isn't much flow, so shipping can continue even in the driest part of the year. The Rhine is a major transportation artery, connecting the port of Rotterdam to the industrial heartland of Germany, so this is rather a big deal.
I'm sure flood control and drinking water supply are also factors, the latter in particular, since the Rhine is a major source of drinking water for a big part of the country.
Thanks to the weirs, the water level can be kept high even when there isn't much flow, so shipping can continue even in the driest part of the year. The Rhine is a major transportation artery, connecting the port of Rotterdam to the industrial heartland of Germany, so this is rather a big deal.
I'm sure flood control and drinking water supply are also factors, the latter in particular, since the Rhine is a major source of drinking water for a big part of the country.
Re: A better way to produce 400x240 1-bit images
I'm working for the state organization, called RWS, that is maintaining them. See https://www-rijkswaterstaat-nl.translat ... to=ajax,nv for more info.
DM41X beta: SN00018.
DM41X: SN00496.
DM42 beta: SN00074.
DM42:SN06020.
DM42 converted to C47 SN08973
DM10L: SN056/100.
DM11L: SN 02058.
DM15L: SN2074.
DM16L: SN2156.
DM15, DM16, DM41
and a whole bunch of the original HP's,
DM41X: SN00496.
DM42 beta: SN00074.
DM42:SN06020.
DM42 converted to C47 SN08973
DM10L: SN056/100.
DM11L: SN 02058.
DM15L: SN2074.
DM16L: SN2156.
DM15, DM16, DM41
and a whole bunch of the original HP's,
Re: A better way to produce 400x240 1-bit images
There's also a nice online resource here to create two bit dithered images.
I tried IrfanView, but the results were too bright and too dark
https://ditherit.com/
Here's an example based on an image of my own, original here: https://www.dropbox.com/s/63l1loayoe6t5 ... .jpg?raw=1
The image rotated and resized to 400x240 pixels: IrfanView 2-bit result: https://ditherit.com/ 2-bit result: PS: Just ordered my DM42 this monday, havent gotten it yet, so I have no idea how the images look on the DM42 display.
Edit:
Just realized, that the image files must be 2 bpp bmp files, they are here:
I tried IrfanView, but the results were too bright and too dark
https://ditherit.com/
Here's an example based on an image of my own, original here: https://www.dropbox.com/s/63l1loayoe6t5 ... .jpg?raw=1
The image rotated and resized to 400x240 pixels: IrfanView 2-bit result: https://ditherit.com/ 2-bit result: PS: Just ordered my DM42 this monday, havent gotten it yet, so I have no idea how the images look on the DM42 display.
Edit:
Just realized, that the image files must be 2 bpp bmp files, they are here:
/Rudi
DM-42 (s/n 06999), HP-42S, HP-35s, HP-11c, HP-32SII (ex HP-41CV, ex HP-75C, ex HP-48G + a lot, really lot of a accessories)
Denmark
DM-42 (s/n 06999), HP-42S, HP-35s, HP-11c, HP-32SII (ex HP-41CV, ex HP-75C, ex HP-48G + a lot, really lot of a accessories)
Denmark