Help with ATI AIW Capture Settings (please)

[Scorpion King]

Not crazy.

My only criticism is that I asked for help, clearly and politely, and you questioned and insulted my needs. Not very constructive. Agreed?

You know, I've had all day to think about what I wanted to write. You know, acraigl said it all for me. Actually acraigl said what I planned on saying myself.

You know, when someone who uses equiptment they worked out and paid for, and they are doing something on their own time, for themselves, to benefit themselves, who are we or who are you to say it isn't right. I have helped people do all sorts of things in my life because they ask me to help them, not because of what I though about what they were doing. I might offer some of my own thoughts from time to time and maybe tell of my experiences hoping they might see the light, but to come right out and call what they are doing crazy! I should hope not.

Like acraigl said above, go straight to #6. If acraigl doesn't want to spend hours and hours in front of a resizing, filtering, deinterlacing, frameserving, encoding, transporting, and whatever else computer trying to get the price is right on a portable device then what is crazy about that? But you know, the sad thing is that we are here now. Who cares about interlaced compatibility with realtime divx capture on a 3 1/2" portable that is going to be played once then deleted. Come on man, read the post.

Ok, I've probably already said too much so I'll quit. Fame me all you want, I can take it. But you leave acraigl alone because acraigl is right. If you don't believe me then view acraigl's profile. What a welcome.



[edit] http://www.pointlisse.com/PMA430/ nice site.

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FulciLives,

Well, technically it's 3.5in.

Just because it's something *you* wouldn't do, doesn't mean it's crazy. Clearly you do not have a 1 hour train commute, 2 kids, an upcoming professional certification that I'm studying for and a fairly routine exercise regimen.

Consequently, the only time I have to catch up on the few shows that I watch is during my commute. As much as I'd like to bring my 42" plasma and home theater on the train with me, that just not going to happen.

Watching on a 3.5in. screen is more than acceptable -- and with all the Archos, Toshiba, Zune, Apple, etc PMP/PVPs on the market now -- apparently I'm not the only one that thinks so. It's perfect for my commute, does not inconvenience me in any way, and I'm happy with it.

Not crazy.

Based on your avatar and signature, one could probably say your into "crazy" things as well, but I'm not judging what makes you happy.

My only criticism is that I asked for help, clearly and politely, and you questioned and insulted my needs. Not very constructive. Agreed?

That makes everything else you say mute.

Oh, and it's moot. Not mute. If everything I said was mute, you wouldn't have heard me in the first place.

Thanks again to Scorpion King and jagabo for all the help!

Amen. Keep doing what you're doing. And ignore the idiots who try to force their opinion on you. Sounds like you are just timeshifting for a 1 hr commute on a train using a 3.5 inch screen. Yes convenience would be the first order. All the time you would spend by taking the wrong advice would be a waste.

Seems like very little has changed around here. Last one out turn off the lights.

[Scorpion King]

I know this thread has already run it's course but I find myself still thinking about it. I can't help but come back and type somemore. I know.....

Fugi said "Capture direct to MPEG-4 ... you people are freaking crazy." But I have ran quite a few internet searches since he wrote that and I find mpeg4 capturing going on all over the place. I don't get it.... Whats makes capturing in mpeg4 so different than capturing in anything else?

Also Fugi said "MPEG-4 does not properly handle interlaced video. At least no form of MPEG-4 you all are using." Again I don't get it. I have been reading my Divx manual, reading at the Divx website, and many other places since he wrote those words and all I can find is that if the source video is interlaced that deinterlacing it may/will cause a reduction in quality. So what is it about capturing interlaced video in mpeg4 that Divx v6.4 or Divx 6.2.5 or OpenDivx v4 does not properly handle?

In one of my posts above I edited the ATI MMC Home Theater MPEG4 preset. Here is a screenshot of the preset. As you can see ATI has set it to deinterlace. So if he is right and OpenDivx v4 can't handle interlaced video then when using the defult ATI preset it is not interlaced, its encoding a deinterlaced source. Right?

I guess I would just like an explination of what Fugi is talking about, since I have been completely unable to find any answers in all my searching on the web since that day. What is it about MPEG4 that makes it so crazy to try and capture video with it, even when the captured video looks so good? What in the world am I missing here..... Someone please explain this. ok.

Ok, I'm done now.
Thanks

[jagabo]

First of all, I think some people have only seen badly compressed Divx videos and have developed the opinion that MPEG4 is crap. I don't know anything about OpenDivx but here are some of the issues regarding MPEG4 codecs.

1) MPEG4 compression is slower than HuffYUV, MJPEG, etc. This makes it more likely to drop frames if you are capturing full motion video at 720x480 or 720x576 with a software encoder. Most computers are now fast enough to capture 320x240 without issues.

2) Up until recently (about a year ago?) most MPEG4 codecs didn't support interlaced encoding. This meant that the chroma components of the two fields were blended together by the YUV 4:2:0 color subsampling used by MPEG4. Even the integrity of the luminance channels could be disturbed. So interlaced sources were immediately degraded by MPEG4 encoding. With interlace support this is no longer an issue. Viewing interlaced MPEG4 is still a bit problematic since many players won't deinterlace properly. Some set-top players may also not display interlaced MPEG4 video properly.

3) MPEG 4 uses long GOP sizes by default. This makes it unwieldy for editing. Try opening a Divx file with VirtualDub and seek backwards, frame by frame, from the middle of the video. It may take several seconds per frame because the program has to search back to the previous key frame, then add in all the predicted frames (as many as 299 frames!) up to the requested frame to reconstruct it.

4) MPEG4 compression leads to significant DCT ringing artifacts, even at the highest bitrates, or constant quantizer 1. Worse than MPEG2 or MJPEG in my experience. And of course, lossless codecs don't have this problem at all.

I never looked at Divx's deinterlacing so I ran a few quick tests. I assumed they would do something simple like dropping one field or blending the two fields together. I was surprised to see they are doing some sort of smart deinterlacing. Similar to a kernel deinterlace with AVISynth at first glance. I didn't test the deinterlacing speed though. It may not be suitable for real time encoding. In any case, the OP is capturing at 320x240 so the capture card is deinterlacing, the codec doesn't need to.

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WOW. Now I would consider the last two posts helpful. Thanks.

[acraigl]

Yeah. Really!

Can I have my can of worms back please? I believe they've spilled when I opened it.

[Scorpion King]

Thanks jagabo. Just what I was looking for.

Later

[jagabo]

Glad to help out. I try to give the facts as I understand them, then let people decide for themselves what they want to do.

[FulciLives]

Glad to help out. I try to give the facts as I understand them, then let people decide for themselves what they want to do.

I prefer to just tell people what to do or at least point out when they are doing something ... oh nevermind.

That was a good point jagabo.

- John "FulciLives" Coleman

[acraigl]

Well, for better, or possibly for worse, I documented the steps needed to record video compatible with the Archos (PMA430) device:

http://www.pointlisse.com/PMA430/html/showArticle.cfm?articleID=64

Thanks again for helping me sort this out!

[Scorpion King]

Nice site. I like it.

I was a little skeptical of your videosoap settings and also of your choice to create a new preset (use 1:4:2 GOP) instead of editing ATIs Home Theater preset (retain ATIs MPEG4 GOP settings) until I did as you and created the preset, captured the video, then played it full screen. Now I say ''''''' well done '''''. Very impressive quality for only a 320x240 frame. My CPU load was <9%. I am surprised these settings works so well.

acraigl, You the man.

Good luck.

[acraigl]

Scorpion King,

Thanks!

A bit of trial and error there on the settings, to be certain. Admittedly, not very scientific, but I played with it enough to make it look good and still be efficient.

I'm most surprised that you even tried my settings! Either you're really into dv, have a lot of time on your hands, or both. Either way, it's appreciated.