JPEGDataType vs FastJPEG

Sim085 · 10 April 2018, 20:42

Hello, I have loaded a jpeg picture with both JPEGDataType and FastJPEG and the result with FastJPEG look better (screenshot attached).

I have read the documentation that comes with FastJPEG and if I understand correctly the improved result is thanks to dithering. Is this correct? Or there is more to it?

Also is there no update for JPEGDataType so results look as good as with FastJPEG? Or this is not possible with data types?

ReadOnlyCat · 11 April 2018, 05:28

I am just guessing from the images your provided but since the JPEG datatype example you show is displayed on a standard WB screen it seems likely that its color count is limited to that of the WB screen. This would explain why that image has very visible dithering.

The right hand side image however, clearly looks like a full screen HAM or HAM8 image and thus would be able to display way more colors than the max 256 of an AGA WB screen.

It is thus not surprising that the latter looks much better.

Sim085 · 11 April 2018, 11:32

Is there a way how to increase the number of colours in workbench to more than 256? (Without a graphics card). Why is there a limit of 256 colours in workbench when AGA can support more than this?

Quote:

Originally Posted by ReadOnlyCat

It is thus not surprising that the latter looks much better.

thomas · 12 April 2018, 19:47

http://eab.abime.net/showpost.php?p=468004&postcount=14

It's only a proof of concept yet, though.

gulliver · 12 April 2018, 22:47

Quote:

Originally Posted by thomas

http://eab.abime.net/showpost.php?p=468004&postcount=14

It's only a proof of concept yet, though.

Is it somehow usable?
What I mean is if it would be a good addition as a checkbox option in a future screenmode prefs program?

thomas · 14 April 2018, 17:28

You would have to rewrite more components than just screenmode prefs. Currently there is no software which supports or even considers WB in HAM mode. At least graphics.library knows that a HAM screen, although it has 8 bitplanes, has only 64 pens, so that WB does not accidently use HAM values for its GUI elements. One important component you would have to rewrite is picture.datatype so that it recognises HAM on the destination screen and returns a respektive bitmap. Otherwise only special programs like the ShowHAM program from my post linked above would make use of it.

gulliver · 14 April 2018, 18:44

Thank you thomas.
I havent thought about the implications it might have on other OS components.
So whilst int theory usable it still will require reworking many OS structures and probably will not be compatible with a lot of 3rd party programs.

kolla · 14 April 2018, 21:28

Quote:

Originally Posted by thomas

You would have to rewrite more components than just screenmode prefs. Currently there is no software which supports or even considers WB in HAM mode. At least graphics.library knows that a HAM screen, although it has 8 bitplanes, has only 64 pens, so that WB does not accidently use HAM values for its GUI elements. One important component you would have to rewrite is picture.datatype so that it recognises HAM on the destination screen and returns a respektive bitmap. Otherwise only special programs like the ShowHAM program from my post linked above would make use of it.

Hum, I used to run Workbench in HAM8 because IBrowse (and aweb?) would then render images in HAM8, and I didn't find a way to open a HAM8 MUI screen. There are also HAM8 (and HAM6) icon packages on aminet, MUI screenmode has a "HAM" ticker... HAM mode for Workbench would be a nice addition in Amiga OS 3.1.4, hah.

http://aminet.net/package/util/wb/hamwb
http://aminet.net/package/util/wb/MUIScrMode1_5
http://aminet.net/package/pix/icon/HAM-Icons

gulliver · 15 April 2018, 16:28

@kolla

I also thought it could be a good addition to 3.1.4 ScreenMode prefs program and was thinking of formally requesting it, but if it is like Thomas says, it seems it requires major surgery for tiny gains, it is a no.

Sim085 · 15 April 2018, 19:33

Thanks Thomas, this worked great. I get a message "hamjpg failed return code 10" but i guess this is because it is still a proof of concept i suppose.

Quote:

Originally Posted by thomas

http://eab.abime.net/showpost.php?p=468004&postcount=14

It's only a proof of concept yet, though.

Hi Kola,

This package "hamwb" looks different from the one linked by Thomas. In it I can see "video6-drivers". Aminet readme says "all you have to do is double click the icon or drop it into WBStartup" but I can't understand to which icon it refers to.

Quote:

Originally Posted by kolla

http://aminet.net/package/util/wb/hamwb

Hi Gulliver, well I would think more software would start to make use this feature while those that do not would look as currently already do. Isn't this so?

Quote:

Originally Posted by gulliver

@kolla

I also thought it could be a good addition to 3.1.4 ScreenMode prefs program and was thinking of formally requesting it, but if it is like Thomas says, it seems it requires major surgery for tiny gains, it is a no.

gulliver · 16 April 2018, 19:22

Well, I just took a leap of faith and requested it.

Now as usual I will get lots of complaints from the devs, and a hundred reasons why it shouldnt or cant be done

Sim085 · 24 April 2018, 00:04

I have installed MUIScrMode1_5
I don't seem to need hamwb because hamjpg works when HAM flag is checked from MUIScrModel1. Is this correct?

What I have left is a datatype to open the jpeg images in HAM mode. I have tried to use this but isn't working

http://aminet.net/package/util/dtype/WarpJPEGdt

I get the error message "Unknown datatype" when I try to open with Multiview.

Quote:

Originally Posted by kolla

Hum, I used to run Workbench in HAM8 because IBrowse (and aweb?) would then render images in HAM8, and I didn't find a way to open a HAM8 MUI screen. There are also HAM8 (and HAM6) icon packages on aminet, MUI screenmode has a "HAM" ticker... HAM mode for Workbench would be a nice addition in Amiga OS 3.1.4, hah.

http://aminet.net/package/util/wb/hamwb
http://aminet.net/package/util/wb/MUIScrMode1_5
http://aminet.net/package/pix/icon/HAM-Icons

30 May 2018, 16:34

There is a JFIF/JPEG DataType that can be configured to render JPEG to HAM modes.

http://aminet.net/package/util/dtype/jfif_dtc
http://aminet.net/package/util/dtype/jfif_FIX

While the readme says "New", it is rather old. Should work with original AmigaOS 3.0 or AmigaOS 3.1.

10 April 2018, 20:42	#1
Sim085 Registered User Join Date: Apr 2009 Location: N/A Posts: 962	JPEGDataType vs FastJPEG Hello, I have loaded a jpeg picture with both JPEGDataType and FastJPEG and the result with FastJPEG look better (screenshot attached). I have read the documentation that comes with FastJPEG and if I understand correctly the improved result is thanks to dithering. Is this correct? Or there is more to it? Also is there no update for JPEGDataType so results look as good as with FastJPEG? Or this is not possible with data types? Attached Thumbnails

11 April 2018, 05:28	#2
ReadOnlyCat Code Kitten Join Date: Aug 2015 Location: Montreal/Canadia Age: 52 Posts: 1,178	I am just guessing from the images your provided but since the JPEG datatype example you show is displayed on a standard WB screen it seems likely that its color count is limited to that of the WB screen. This would explain why that image has very visible dithering. The right hand side image however, clearly looks like a full screen HAM or HAM8 image and thus would be able to display way more colors than the max 256 of an AGA WB screen. It is thus not surprising that the latter looks much better.

12 April 2018, 19:47	#4
thomas Registered User Join Date: Jan 2002 Location: Germany Posts: 7,002	http://eab.abime.net/showpost.php?p=468004&postcount=14 It's only a proof of concept yet, though.

14 April 2018, 17:28	#6
thomas Registered User Join Date: Jan 2002 Location: Germany Posts: 7,002	You would have to rewrite more components than just screenmode prefs. Currently there is no software which supports or even considers WB in HAM mode. At least graphics.library knows that a HAM screen, although it has 8 bitplanes, has only 64 pens, so that WB does not accidently use HAM values for its GUI elements. One important component you would have to rewrite is picture.datatype so that it recognises HAM on the destination screen and returns a respektive bitmap. Otherwise only special programs like the ShowHAM program from my post linked above would make use of it.

14 April 2018, 18:44	#7
gulliver BoingBagged Join Date: Aug 2007 Location: The South of nowhere Age: 46 Posts: 2,358	Thank you thomas. I havent thought about the implications it might have on other OS components. So whilst int theory usable it still will require reworking many OS structures and probably will not be compatible with a lot of 3rd party programs.

15 April 2018, 16:28	#9
gulliver BoingBagged Join Date: Aug 2007 Location: The South of nowhere Age: 46 Posts: 2,358	@kolla I also thought it could be a good addition to 3.1.4 ScreenMode prefs program and was thinking of formally requesting it, but if it is like Thomas says, it seems it requires major surgery for tiny gains, it is a no.

16 April 2018, 19:22	#11
gulliver BoingBagged Join Date: Aug 2007 Location: The South of nowhere Age: 46 Posts: 2,358	Well, I just took a leap of faith and requested it. Now as usual I will get lots of complaints from the devs, and a hundred reasons why it shouldnt or cant be done

30 May 2018, 16:34	#13
Christoph Feck Posts: n/a	There is a JFIF/JPEG DataType that can be configured to render JPEG to HAM modes. http://aminet.net/package/util/dtype/jfif_dtc http://aminet.net/package/util/dtype/jfif_FIX While the readme says "New", it is rather old. Should work with original AmigaOS 3.0 or AmigaOS 3.1.

Currently Active Users Viewing This Thread: 1 (0 members and 1 guests)