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Comment by appstorelottery | Hacker News Reader

This is great stuff! As a side note, I wonder if anyone has created a HAM viewer that runs in the browser? I remember HAM flickering by necessity and being amazed by 4096 colors on-screen at once. There was a certain quality of HAM images on the Amiga that made them instantly identifiable.

https://en.wikipedia.org/wiki/Hold-And-Modify

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HAM doesn't flicker. The issue with HAM is that you're limited in terms of abrupt colour changes.

It's straightforward to convert HAM to PNG etc.

It would have sometimes been used together with interlaced mode to double the number of lines and that did flicker.

Flickering? I don't recall flickering, but I do recall that EHB (extra half brite) to get to 64 colors might have had fringing issues, but that's about it.

Interlacing might have flickered too, depending on your monitor. (Most monitors Commodore made would flicker in interlace mode, but I believe there were some higher end ones that did not).

You were probably seeing an interlaced video mode, which flickered HAM or no HAM. The signature of HAM was there would be odd color barf at the edges of objects if the colors changed too quickly going left to right because of the hold-and-modify encoding. You saw that a lot with ToasterPaint but when it rendered to the video output it was fine (and even in 24bit color).

I remember HAM being stable until you moved the mouse and then it would flicker until you stopped moving the mouse because the scan line interrupts would be interrupted by the mouse, throwing the sensitive scan line timing off.

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