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So I'm pretty new to video production and I'm struggling with properly rendering 1080p game footage. My main problem is that multiple frames of the output video are pretty pixled, looking like this enter image description here

I'm working with footage recorded using fraps and I'm editing with Sony Vegas pro 12 atm. My project settings are matched to the footage I'm using in this particular project:

enter image description here

No doubt I messed up the rendering options somehow, since the raw footage looks okay. Here are the render settings I used for the shown output:

enter image description here

Can someone help me get those pixled scenes out of the video? Desired output format is MP4 since it seems easier to handle for youtube uploads.

Thanks in advance, I hope someone can help me with this.

Best regards, Rickyfox


Edit:

I just discovered that about a minute of the output video just turned out black with the scene settings being exactly the same as the rest - anyone have a clue what that could be?

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1 Answer 1

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It honestly looks like something got corrupted with your export. Have you tried encoding it more than once? 12 megabits per second with a 24mpbs peak should be more than sufficient for high quality 1080p video. If anything, it may be excessive. The quality you are getting looks more like what I'd expect at sub-1 mbps video for this quality level. As an aside, it is worth noting that 2 pass will produce better results, thought it will extend encoding time.

One other thought is to try watching it in more than one viewer. It is possible that the viewer you are using is struggling to decode the high data rate fast enough which could also result in the block issues you are seeing. Basically, it looks like some of the blocks in the H.264 file are not encoding or decoding properly and that either means file corruption or insufficient decoding speed.

I guess to rule out data rates, you could try increasing it to 30mbps with 45mpbs peaks. It shouldn't have to be that high (that's the high end of bluray data rates), but it should rule out the data rate entirely.

Update: From some additional reading, I would try turning on 2-pass and turning on the deblocking filter. It supposedly should help.

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I did render the same footage with similar settings before and also received similar output, tho I cannot say it was the same output. Edit: watched it with media player instead of vlc and it looks the same –  Rickyfox Jul 29 '13 at 15:48
    
@Rickyfox - how did it differ? Were the distortions on different frames? –  AJ Henderson Jul 29 '13 at 15:50
    
I no longer have the previous render here, so I can't say for sure if the errors occured on the same frames. What I can say for sure is that there were these pixled frames in a previous render with similar settings. –  Rickyfox Jul 29 '13 at 15:51
    
@Rickyfox - take a look at my most recent update. Doing some more reading, it sounds like that particular encoder may need you to do 2 pass and use the deblocking filter. It apparently can have some motion related issues with the encoding. –  AJ Henderson Jul 29 '13 at 15:57
    
@Rickyfox - no, on the screen with "Variable Bit Rate" there is a "Two Pass" checkbox. This means that it runs through the video once to figure out where it needs to use the most data and then encodes according to the calculations from the first pass. Basically, VBR works by trying to approximate how much data to use based on how much change their is. Two pass makes a better approximation instead of simply guessing (which can result in insufficient data left over for some really high motion scenes.) –  AJ Henderson Jul 29 '13 at 15:58
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