Atari 2600 S-Video Mod and Capturing Video

[ChrisKewl]

I have a light sixer with an s-video mod.

Here is the S-Video mod I did in early 2014:

http://electronicsentimentalities.com/Assembled%20Mods.html

Now from the Framemeister XRGB-Mini to my TV it looks good, it doesn't flicker very well at all on my newer TV but it's consistent video so I can see all the elements.

The capture card I use, however, isn't seeing it so well however. I have a Startech USB3HDCAP and the sync is a bit off. The Startech claims it is doing exactly 60fps, so does this mean that the Atari isn't exactly doing 60fps?

Here is a snippet of video from last night to show you the issue:

http://www.twitch.tv/kilokahntv/v/25624895

EDIT: I also should mention that static image games, such as Stampede and Dodge 'Em work quite well. Anything that flickers is a crapshoot. Here is the whole video from last night, the Atari 2600 video starts around the 16 minute mark:

http://www.twitch.tv/kilokahntv/v/25487300

Edited November 14, 2015 by ChrisKewl

[Andromeda Stardust]

Any sprite that flickers at 30Hz will create venitian blinds on an HDTV. Most cheap upscalers attempt to deinterlace 240p video as 480i instead of line doubling the video to 480p.

 

Further problems result because most websites and many capture devices limit the frame rate to 30Hz. This often has the effect of deleting every other frame often resulting in the flickered sprites completely disappearing as with your twitch video.

 

You need to capture raw footage at 60Hz, not 30Hz, and deinterlace the video manually using a blend filter in post processing. For instance, if I capture a video using my Hauppauge USB (which completely barfs on Atari output likely due to an incorrect timing, 228 color clocks per scanline instead of 227.5, but that is another issue entirely), it stores the stream as 720x480i encoded Mpeg2.

 

If I upload this stream direct to youtube, the conversion software will delete every other frame when converting to 30Hz 480 progressive, resulting in some sprite data being deleted. I have to take the interlaced video and input it into an application like Handbrake in order to manually convert it to progressive 30Hz. For 240p source, you would want to use the blend option, which will preserve the pixels without blurring them during 480p upscale.

 

Since you were live streaming, such conversion is likely impossible. You also used the frame meister or RGB mini to upscale the video output from the Atari so it may be the upscaler or it may be that you are capturing a 30Hz stream instead of 60Hz, tossing out every other frame. In order to get rid of the interlaced artifacts or deleted sprite data, you have to use an external video editing program (I recommend Handbrake) to deinterlace the video by blending the frames. The end effect will be similar to the Alt-P "Phosphor Effect" in Stella emulator. Please note it's likely impossible to perform a proper conversion on the live feed. If your capture device doesn't have the bandwidth to record full 1080p60, you may need to reduce the output settings on the frame meister to 720p or 480p.

 

I hope this helps for future recordings.

 

I know it looks like crap, but pointing a camera at the TV screen is the only way I know to capture Atari since my Hauppauge USB doesn't play nice with my AV modded 7800. You obviously have fancier equipment than I do so hopefully you can find a way to fix the issue. There are also two WIP Donkey Kong homebrews for the 2600, DK Arcade and DK VCS. Both of them use multisprite kernels to display multiple colors so this may be helpful to test video capture with. The DK sprites in both games look horrid with the even or odd frames deleted and must be blended together in post processing.

[ChrisKewl]

Since you were live streaming, such conversion is likely impossible. You also used the frame meister or RGB mini to upscale the video output from the Atari so it may be the upscaler or it may be that you are capturing a 30Hz stream instead of 60Hz, tossing out every other frame. In order to get rid of the interlaced artifacts or deleted sprite data, you have to use an external video editing program (I recommend Handbrake) to deinterlace the video by blending the frames. The end effect will be similar to the Alt-P "Phosphor Effect" in Stella emulator. Please note it's likely impossible to perform a proper conversion on the live feed. If your capture device doesn't have the bandwidth to record full 1080p60, you may need to reduce the output settings on the frame meister to 720p or 480p.

 

The Framemeister RGB-Mini claims it is sending the 60hz to the capture card, the capture card claims it is seeing 60hz as well. This sounds like to me that the capture card isn't happy since I am getting everything to my TV just fine. This is why my thought is maybe its not sending exactly 60hz or the card isn't grabbing exactly 60hz, something is off on the sync maybe? If it's always skipping the blink frame, shouldn't it always be on or always be off but not rotate like it is doing?

 

What I can do is also plug the S-Video into the capture card directly and see what it does. It is food for thought nonetheless.

[Andromeda Stardust]

 

The Framemeister RGB-Mini claims it is sending the 60hz to the capture card, the capture card claims it is seeing 60hz as well. This sounds like to me that the capture card isn't happy since I am getting everything to my TV just fine. This is why my thought is maybe its not sending exactly 60hz or the card isn't grabbing exactly 60hz, something is off on the sync maybe? If it's always skipping the blink frame, shouldn't it always be on or always be off but not rotate like it is doing?

 

What I can do is also plug the S-Video into the capture card directly and see what it does. It is food for thought nonetheless.

The Atari and most other 240p consoles do not output exactly at 59.94Hz so the upscaler may be compensating for that by duplicating or skipping a frame ever so often. This is why the blink frames occasionally switch between even and odd fields. The stream online is definitely 30Hz so somewhere the video data is being deleted. Svideo capture may create venetian blinds or delete every other frame depending on the type of deinterlace filter used by the capture software. You really want to blend the frames and upload/stream at 30Hz so that both the even and odd sprites show up.

 

I have DSL at home and I would never have the uplink bandwidth to stream anything live so I have the option of reencoding the video stream from my capture card from interlaced mpeg2 to progressive 30Hz MP4 using handbrake. Your capture hardware may or may not like the S-Video feed from your Atari depending on how tolerant it is.

[ChrisKewl]

The Atari and most other 240p consoles do not output exactly at 59.94Hz so the upscaler may be compensating for that by duplicating or skipping a frame ever so often. This is why the blink frames occasionally switch between even and odd fields. The stream online is definitely 30Hz so somewhere the video data is being deleted. Svideo capture may create venetian blinds or delete every other frame depending on the type of deinterlace filter used by the capture software. You really want to blend the frames and upload/stream at 30Hz so that both the even and odd sprites show up.

 

I have DSL at home and I would never have the uplink bandwidth to stream anything live so I have the option of reencoding the video stream from my capture card from interlaced mpeg2 to progressive 30Hz MP4 using handbrake. Your capture hardware may or may not like the S-Video feed from your Atari depending on how tolerant it is.

 

Here is an attempt at 60FPS on Twitch, a little bit better:

http://www.twitch.tv/kilokahntv/v/25871872

 

I will have to look at capturing the video to re-render after the fact though, I'll still broadcast live at 60fps but then re-render to 30fps after maybe. I am very familiar with Handbrake though, so I can do something after the fact if necessary.

 

You've been awesome sharing this information, it's been a big help so far. If you can think of anything else, I'm all ears.

[Andromeda Stardust]

^^Asteroids as well as the Harmony menu looks much better now that you can see everything despite the flicker!

[ChrisKewl]

I guess if I have to play live this would be the way to go. I also took this video to Handbrake at a Fast interlace and it's not horrible either, it does blink approximately once a second and is readable on the Harmony screen. If this is how I have to live with it then I guess I'll do this.

 

Thanks again!