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cannot get red frame artifact to go away
Hello,
Please pardon my naivete in advance, and excuse me if I have not been looking hard enough, but I am having a major problem getting After Effects to render MPEG2 footage to FLV with an alpha channel without creating a single frame flash of pure red in the final output. I’ve tried searching the net and have not found any useful information.
Here what I know:
1. The footage came off of a Sony Handycam of some sort; I do not know if it was captured as interlaced or not, but I do know that once in After Effects, in the “interpret footage” dialogue the “seperate fields” option defaults to “lower field first”. I have tried rendering it this way, and I have tried rendering it with “seperate fields” set to off, no difference, still a red flash at 3:19 in the rendered footage.
2. The footage is basic talking head stuff, very little motion, against a professional greenscreen under professional lights. (I admit the lighting was set up by me and so the actual set up was amateur, although I was following instructions.)
3. In after effects, I used Keylight to key out the greenscreen, and then the matte choker to get a little cleaner edge on my subject, and that’s it.
4. The render queue settings are Lossless, RGB + Alpha, Millions of Colors, Premultiplied.
5. Composition framerate is 29.97
6. Although I can not find the setting right now, and I am not sure of the terminology, the “output framerate (something like that) is base30 drop.
I have tried outputting to different formats (mov, avi . . . ) and it still happens.
When I view the footage from my hard drive (I copied it there directly from the camera via USB (the camera had no firewire port)) in Windows Media Player, I see no red frame and I see nothing out of the ordinary as the playhead passes by 3:19, or anywhere else for that matter.
If anyone could tell me what might be happening, or suggest a line of inquiry, I’d be much obliged.
Flat out solutions would be fine as well 🙂
Thanks,
Ed
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15 Replies
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try edit>purge>all… or better yet, just shutdown for a minute and reboot. i’ve had a few unexplainable things show up in renders, and it seems to be a problem with the ram getting not getting fully purged after a while. purging or rebooting often helps.
i’m curious, if you go to composition>background color, is red set as the bg color?
Kevin Camp
Senior Designer
KCPQ, KMYQ & KRCW -
[ed oconnell] “I am having a major problem getting After Effects to render MPEG2 footage to FLV with an alpha channel”
Is your source footage MPEG2? If so you should consider encoding it to another codec without interframe compression like Photo JPEG. This may not fix the problem you’re experiencing, but similar issues can appear when using source footage encoded to MPEG2.
Darby Edelen
Designer
Left Coast Digital
Santa Cruz, CA -
Hmmmm . . . I’ll try purging, but I have a feeling it is something else, perhaps in the source, only because it shows up at the same time each time, and I’ve tried several times over a week or so, so the computer has been restarted. The background color is actually set to black, and the only other color I’ve introduced is a white solid which I used to see how the transparency looked. I deleted that layer prior to rendering.
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Okay, I’ll try that and see what happens and report on it. The footage came off the camera as MPEG2, which is giving me other headaches as well (apparently the audio channel is not recognized by Premiere); I will have to see whether or not there is a way to change encoding at the source.
But in the meantime, just so I am clear, is what you are suggesting encoding the raw footage to Photo JPEG, saving it that way, and then applying my effects? I think that is what I am hearing, so I am going to try it that way.
The final product needs to be .flv, and I confess I am a total newbie at After Effects. Once in Flash, I can swim, but for the moment, I’m just treading water.
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I’m with Darby. Use QT Pro or something to encode the footage to something like Photo-JPEG or Animation, then replace the footage in AE with this re-encoded footage.
By the way, can you check which camera was used? Check the baseplate.
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if its been restarted, then purging shouldn’t help… converting the mpeg2, as darby suggested, may help. you will probably want to use a conversion utility other than ae (premier pro should work), since ae is the one giving you the red frame…
once you have converted it to photojpeg (or another codec that doesn’t use temporal/intrerframe compression), take it into ae and see if it helps.
Kevin Camp
Senior Designer
KCPQ, KMYQ & KRCW -
The camera is a Sony HandyCam DCR SR300.
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Yeah, it’s an MPEG-2 camcorder. Convert the footage as Darby suggested before you do anything with it in AE. Then we’ll see what’s what.
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Well . . . I suppose this is a cop out, but your insights have resulted in a temporary fix. I ended up re-doing the key in Premiere and exporting to .flv from Premiere, and I am no longer seeing the artifact. At first, Premiere would not recognize the audio channel, but I found another thread on that, and now I have a less sophisticated key (the edges of my subject don’t blend quite as smoothly with the background as they did out of After Effects), that will get me through the next week or so while I continue this investigation.
I can’t thank any of you enough for taking the time to respond to me.
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Are we the only two people on the interweb with this crazy red frame problem? I have a big project due in a few days and I can’t get rid of these red frames to save my life. Purge will not help. Also, every format seems to have it. It is not in my source material. Is this a CS3 bug? If any fellow After Effects user can give me some advice I would be forever indebted. Thanks
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