Poor x264 performance in Sony Vegas

[LoXodonte]

I like re-rendeing my large video captures into x264 as it seems to make video less blocky when compared to xvid. However in Vegas I've noticed that the x264 clips do not like to preview well. I'm having to render small scenes just so I can tell whats going on. Is this just a fact of life with this codec in these circumstances? Should I take the quality hit and go back to xvid quantinizer 2?

[Guest]

Is this just a fact of life with this codec in these circumstances? What do you mean by "this codec"?

[LoXodonte]

What do you mean by "this codec"?

x264 in comparison to xvid...I dont' have this problem with xvid.

[Guest]

x264 is not a codec.

What you should be investigating is what decoder is being used in Vegas to decode AVC video.

[LoXodonte]

I thought a codec was a container term for the encoder/decoder.

So do I need to start another topic and what do I need to ask exactly?

[LoXodonte]

I don't know if this thread tells me anything, I think he maybe talking about playback after the fact. This video is absolutely tedious to work on now.

[Blue_MiSfit]

No, a codec in the literal sense of the word is software that provides both an encoder and a decoder. x264 is an encoder only.

In order to figure out why you're getting poor editing performance in Vegas on files created by x264, we need to know more about those files.

Please run mediainfo on an example file, and post the text results here.

Chances are, you are using long GOPs (per the x264 defaults), and perhaps some parts of the H.264 standard that Vegas's H.264 decoder does not enjoy. If we can identify this, we can help you settle on encoder settings for x264 that will produce files that work smoothly.

Also, as a test, try encoding one of your captures with the following example (total shot in the dark) x264 command:


x264.exe input.avs --output "output.mp4" --crf 16 --tune fastdecode --preset fast --level 41 --slices 4 \
--vbv-maxrate 62500 --vbv-bufsize 62500 --keyint 24


This will generate a very high quality file compliant to H.264 high profile @ level 4.1, with very short GOPs (at most, one second assuming 24p, use --keyint 30 for 30fps), and no CABAC which can be slow for decoding / editing. It also uses 4 slices in case the Vegas decoder supports slice based threading only, and should encode rather quickly. We can tweak this example further if it works for you.

~MiSfit

[LoXodonte]

That makes sense, thx for the explanation. I ran media info and got the following:

General
Complete name : F:\Media\Myoelectric Video\Captures\BFBC2\Sorted\Montage\1-31-2010_p7.avi
Format : AVI
Format/Info : Audio Video Interleave
File size : 15.8 MiB
Duration : 9s 467ms
Overall bit rate : 14.0 Mbps
Writing library : VirtualDub build 29808/release

Video
ID : 0
Format : AVC
Format/Info : Advanced Video Codec
Format profile : High@L3.1
Format settings, CABAC : Yes
Format settings, ReFrames : 1 frame
Codec ID : H264
Duration : 9s 466ms
Bit rate : 13.7 Mbps
Width : 960 pixels
Height : 540 pixels
Display aspect ratio : 16:9
Frame rate : 30.000 fps
Resolution : 8 bits
Colorimetry : 4:2:0
Scan type : Progressive
Bits/(Pixel*Frame) : 0.879
Stream size : 15.4 MiB (98%)

Audio
ID : 1
Format : MPEG Audio
Format version : Version 1
Format profile : Layer 3
Codec ID : 55
Codec ID/Hint : MP3
Duration : 9s 467ms
Bit rate mode : Constant
Bit rate : 320 Kbps
Channel(s) : 2 channels
Sampling rate : 48.0 KHz
Video delay : 20ms
Stream size : 370 KiB (2%)
Alignment : Split accross interleaves
Interleave, duration : 35 ms (1.05 video frame)
Interleave, preload duration : 500 ms


I haven't tried the x264 configuration you mentioned yet, I render out several mini clips, so if there is anyway to get that configuration in the gui form, I could save the process settings.

[Ghitulescu]

As you can see from your own log, the codec is called H264 (correct H.264), while the software is called x264.

[Dark Eiri]

You're using VirtualDub and x264 VfW to get H264 AVI files? I guess this is your problem.

I've been feeding x264 on MP4 to Vegas for ages and the decoding is flawless. And the preview window works perfectly. I'm not sure if their decoder isn't GPU accelerated, because it's really fast.

That using Vegas 9, of course. If you're using an older version, maybe the decoder is having issues.

[LoXodonte]

No I'm on Vegas 9 currently but had the same issue in 8.

Actually, I encode the video initially using TMPGXpress. I have several batches of clips that I compress down into one clip in a manageable size using the Xpress app. I then sort the footage by loading it up in Virtualdub, and saving individual clips using direct stream copy for both audio and video.

So, I'm unclear of what I need to do at this point.

[Dark Shikari]

So, I'm unclear of what I need to do at this point.Encode it properly into a supported container (i.e. not AVI)?

[LoXodonte]

Sorry I've always worked with AVI's and assumed it was the only container for the streams I was using . I assume a mp4 file can contain a lamemp3 stream as well then? Can I rebuild my existing videos in the correct format? Or what program do I need to use to batch encode and sort several files.

[Blue_MiSfit]

Take a look at StaxRip. It has the most comprehensive, robust batch support of any free GUI I've ever tried.

~MiSfit

[LoXodonte]

thats def a cool program, but I also use virtualdub to split and sort my clips. Example, TMPG Xpress creates a very large .avi file using x264 ecnoding. I load that file into Virtualdub, set video to direct stream copy, and sift through the video saving only the small selections that I like.

So do you suggest that at that point I run a batch of all these avi's through StaxRip? Really, I'm thinking my best solution at this point is just to use xvid. Its not nearly as laggy in vegas.