Page 1 of 2

Re: ZX81 BMP converter

Posted: Fri Aug 14, 2020 12:01 pm
by kolbeck
pavero wrote: Thu Aug 13, 2020 8:03 pm Maybe small improvement. It doesn't work for BMP files without a border - 256 x 192 pixels only. ;)
Hi [mention]pavero[/mention] - please try again, it should now support all sizes from EO

* No Border: 256x192 pixels
* Small Border: 264x200 pixels
* Standard Border: 320x240 pixels
* Large border: 400x300 pixels
* Full frame: 413x312 pixels

The PNG will of course have the same size as the input file. Also for large and full frame, the adjustment is not 100% correct - looks like the actual dump is not centered :-) Will be fixable when adjustment parameters are added.

/Thomas

Re: ZX81 BMP converter

Posted: Fri Aug 14, 2020 1:04 pm
by kolbeck
solaris104 wrote: Thu Aug 13, 2020 8:19 pm Some screenshot from EightyOne need correction.

Image

Image
[mention]solaris104[/mention] - please try out the added correction parameters

/Thomas

Re: ZX81 BMP converter

Posted: Fri Aug 14, 2020 1:49 pm
by 4thRock
kolbeck wrote: Fri Aug 14, 2020 12:01 pm * Full frame: 413x312 pixels
Interesting. 312 lines seem to be the full extent of the generated TV signal, including non-visible sync lines:
Image
( http://blog.retroleum.co.uk/electronics ... -voltages/ )

Re: ZX81 BMP converter

Posted: Fri Aug 14, 2020 2:05 pm
by kolbeck
I have not seen any full frame programs yet, maybe a little challenge for our experts? :-)

Re: ZX81 BMP converter

Posted: Fri Aug 14, 2020 2:45 pm
by Solaris104
kolbeck wrote: Fri Aug 14, 2020 1:04 pm @solaris104 - please try out the added correction parameters

/Thomas
Thank you, it's works :-)

Re: ZX81 BMP converter

Posted: Fri Aug 14, 2020 4:13 pm
by pavero
kolbeck wrote: Fri Aug 14, 2020 12:01 pm
pavero wrote: Thu Aug 13, 2020 8:03 pm Maybe small improvement. It doesn't work for BMP files without a border - 256 x 192 pixels only. ;)
Hi @pavero - please try again, it should now support all sizes from EO

* No Border: 256x192 pixels
* Small Border: 264x200 pixels
* Standard Border: 320x240 pixels
* Large border: 400x300 pixels
* Full frame: 413x312 pixels

The PNG will of course have the same size as the input file. Also for large and full frame, the adjustment is not 100% correct - looks like the actual dump is not centered :-) Will be fixable when adjustment parameters are added.

/Thomas
Perfect! :-)

Re: ZX81 BMP converter

Posted: Sat Aug 15, 2020 9:26 pm
by kolbeck
[mention]4thRock[/mention] - look at this:
ZX81 Video Nonstandard Picture Size

The official picture size is 32x24 tiles (256x192 pixels) with huge borders. However, on a PAL screen, the ZX81 can display 40x34 tiles (320x272 pixels).
Info found on this page: https://problemkaputt.de/zxdocs.htm#zx8 ... esgraphics

/Thomas

Re: ZX81 BMP converter

Posted: Mon Aug 17, 2020 9:03 pm
by kolbeck
I have renamed the tool to ZX81 Screen Converter, as it how handles more than BMP files as input.

What is it?
ZX81 Screen Converter is an online tool target preserving ZX81 software for ZXDB, helping to create proper screen shots in formats like s81, scr and png. It take as input a screen dump file and converts to different formats. Allowed input formats:
* .bmp as produced by various emulators (e.g. EightyOne and SZ81)
* .png as produced by the ZX81 emulator for iOS (by Kevin Palser) and Retrospecs (Pixelate your pics!) also for iOS
* .s81 for standard non-hires ZX81 screens (a sequence of 768 character codes from the ZX81 charset)
* .scr widely used screen format used for ZX Spectrum screens, suitable for preserving ZX81 hi-res screens

It will always produce the following output:
* .s81 for standard non-hires ZX81 screens (a sequence of 768 character codes from the ZX81 charset) - if it is a hi-res screen, or the offset parameters is not correct - this will just be garbage.
* .scr for hires screens with regular size (in ZX Spectrum display format)
* .png for big screens, that goes beyond the 256x192 size (for example MaxDemo or QS Defenda)
* .txt for printing in console - mostly for fun (ANSI control codes to implement inverse print) - as with s81, it will be gargabe if hi-res or offset parameters are not aligned to 8x8 blocks. Use this to verify correct offset parameters.

For iOS ZX81 emulator, make sure to have at least v1.9.0 - as this version fixes some issues with the screen dump.

All border sizes from EightyOne with the following sizes are supported:
* No Border: 256x192 pixels
* Small Border: 264x200 pixels
* Standard Border: 320x240 pixels
* Large border: 400x300 pixels
* Full frame: 413x312 pixels

You can find the online converter here: https://zxinfo.dk/scr/ - and as always, leave a comment here :-)

/Thomas

Re: ZX81 BMP converter

Posted: Fri Oct 16, 2020 5:31 pm
by PeterJ
I'm a bit late to the party with this one [mention]kolbeck[/mention], but just to say Excellent!

Re: ZX81 BMP converter

Posted: Tue Feb 09, 2021 8:21 pm
by PeterJ
Hi [mention]kolbeck[/mention],

I did a few screens last night and it worked great, but this evening I'm getting 'Error: Request failed with status code 404' when I upload this file.

https://drive.google.com/file/d/1u7KcJZ ... sp=sharing

Re: ZX81 BMP converter

Posted: Tue Feb 09, 2021 9:16 pm
by kolbeck
Let me check - some work are being done in relation to the V3 upgrade - might give some noise, thanks for the heads-up

/Thomas

Re: ZX81 BMP converter

Posted: Tue Feb 09, 2021 9:28 pm
by kolbeck
[mention]PeterJ[/mention] - missing rule in config, it should be running again now!

thanks

Re: ZX81 BMP converter

Posted: Tue Feb 09, 2021 9:34 pm
by PeterJ
kolbeck wrote: Tue Feb 09, 2021 9:28 pm @PeterJ - missing rule in config, it should be running again now!

thanks
Thanks Thomas. All working now. Cheers.

Re: ZX81 BMP converter

Posted: Wed Apr 19, 2023 12:42 pm
by kolbeck
ZX81 Screen Converter - just got a small update, everything should be working as before.

* Improved layout, where converted files are easy accessible
* Support for drag'n'drop of a file for easy conversion

Before:
Image Image

After:
Image Image



/Thomas

Re: ZX81 BMP converter

Posted: Thu Jul 13, 2023 8:30 pm
by kolbeck
Another small update, it now supports ZX80 screenshots - in the sense that if marked as ZX80, it will be able to identify the characters used by ZX80 which font is a bit different than on ZX81 (and to large extend ZX Spectrum).

Image uploaded, not marked as ZX80 (look at most right image, which is the ASCII identified - in this case mostly garbage)
Image

Same image now marked as ZX80 - the characters are identified correctly and produces nice ASCII representation.
Image