How to make a standalone animation viewable on ST

[+KayBee]

Hi Again Atarians,

 

I made a 40 frame animation using Tom Hudsons Raytracer from Start magazine, and I would like to make a standalone movie file or clickable demo that can be run on the ST. Ideally using delta-style compression, since most of the frame are is static (other than reflections). The images are currently in .pi1 format. Anyone know of a tool I can use to make an animation file that I can share? Attached is a sample frame.

 

Thank you.

 

KB

[ParanoidLittleMan]

I made some AV playback programs and systems for STE (DMA audio is really needed for) :  http://atari.8bitchip.info/movpst.php

It is based mostly on fast disk access and just loading frames and audio data in row. Some packing, even simplest would just make it slower. Especially in case of IDE access, and that's is what gives highest speed on ST (not DMA).

But this is different. So, only 40 frames of 16 color Atari screens, I guess. What frame rate ? With 10 fps it will be only 4 seconds.

Cyber Studio is what uses delta compression for animations created with it. And I used delta compression (my code) in audio player. That's all what I know about such SW for ST.

Now, I think that I can do code, short program for your purpose. And I guess that resulting file may fit in free RAM of 512 KB machine - calculating with 40 frames x 32 KB = 1.3 MB for unpacked, so packed may be about 200 KB or like. 

So, it you can supply those PI1 files, ZIPped, it would be good start. For instance, size of ZIP will indicate how well it is compressible - like if ZIP is 50 KB, we may expect 200 KB for delta packing (just a rough estimation).

 

[+KayBee]

Thank you PLM,

 

Ideally I was hoping for a 1040ST to play a file from RAM, like a demo. Double click and it plays as fast as possible, meaning as close to 30fps as we can get. My thought on compressing based on deltas was that largely the frame is the same, so perhaps as a bonus it would play on a 520ST. 

Thank you for the offer to help. Excellent.

 

KB

thank_you_PLM.zip

[ParanoidLittleMan]

OK. So, it needs to play in loop, until user abort ? I will set key for abort - like Q. And think that should have screen refresh rate set with 5 and 6 for 50 and 60 Hz.

For good looking draw on screen must be syncronised with video. So, at PAL video it will be 25 fps. Optionally 30 (when user press 6), but then may loose colors, depending on what monitor is used.  I'm sure that will fit in 512 KB RAM. And will be shorter than 400 KB - my packer is the best ! ?

 

[+KayBee]

That is excellent. Now one more thought. The reflective balls are metal, ideally at frame 37, and every 37 frames, a high audio note is played, a "ping" sound. Sort of like the amiga juggler demo. If you can add that, what do you need from me?

 

K

[ParanoidLittleMan]

I did code for generating delta data between 37 adjacent frames (latest is diff between 37 and 01 because loop). Diff file size is about 150 KB, so it will work fine with 200 KB free RAM .

Made test SW too, and it is OK. Tomorrow will make playback SW.

Considering sound effect: best would be PCM sample of that sound - WAV format or MP3. Then I can convert it to STE DMA compatible format. It will work only on STE, TT, Falcon, with good quality. To make sound on STs needs some PSG (soundchip) programming, what is not my area, but may be done later. Of course, I need to hear that sound, so sample for sure ...

[+KayBee]

Interesting. I can provide a sample late tonight. Would playing a sample cause a "pause" during playback? The ST has a sound chip, would playing a note (beep of pleasing frequency) be less computationally "expensive?" I ask respectfully, in deference to your knowledge. It also seems you are a wizard, so maybe a sample is no problem. 

[ParanoidLittleMan]

What causing slowdown, pause during playback is sample playback via PSG chip (ST) . STE DMA playback slowdowns not at all.

I can do little more than simple beep, but of course need to hear original. DMA sample playback is best, and not hard to program, especially if done such thing already.

And it will not cost much RAM because time is short.  Just calculate:  whole video of 37 frames at 30 fps takes some 1.3 sec.  If sound is half sec, it will be some 12.5 KB only.

No need to rush with upload, now is time for sleep here, and tomorrow I will be pretty busy ...

[+KayBee]

Really interesting, yes your logic makes sense. When it is convenient for you please check the attached wav. As for other graphic I will create it on the weekend. 

stpingv1.zip