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Beave
21st June 2005, 16:19
I was trying out XVID with HDTV material for a while. I got my hands on some 720p 3ivx Episodes and was surprised by the quality @ low bitrate.

Now I'd like to try x264 with AAC 5.1 in mp4 container. My sources are either 1080i or 720 transport streams. My target should be 720p AVC. Depending on the source I would like to put 6 Episodes (around 42 min) on one DVD (746mb each). Or maybe only 4 (1120 mb each). I will have to see how good x264 compresses the video.

What are suggested ways to receive a good result without overkill on encoding time and playback cpu-usage?

First, what x264 build should I use? I donwloaded both the build from x264.nl (bob0r) and the X264CLI_rev269_mmx.7z suggested for MEGui. Both builds have a x264.exe. Can they both be used for MEGui?

Now the defaults in MEGui seem a lot different to the defaults of bob0r's build. And even there the vFW (in VDub) Option-Defaults are different. The VDub version doesn't default to 8x8 DCT, whereas the x264gui does.
MEGui defaults for AVC seem to be very careful and have a lot of x264 options disabled. Why is that?

Is there a speed advantage in using mencoder over x264.exe or over VDub? I have a AMD64 3000+.

Some of the sources have lots of blocks in them. Does the Inloop deblocking take care of it or should I still use cpu=4 in the avs to get rid of those?

I'm asking because as I understand encoding high resolutions is different from encoding normal DVD resolutions. Maybe some configuration options are not as usfull at this size or some other option is very important for good PQ@720p.

Beave
23rd June 2005, 16:42
I did some test encodes with 720p. Looks pretty good so far, but the playback is pretty harsh on the cpu using ffdshow & haali. I have 100% cpu usage with my AMD64 3000+, 1gb ram, geforce 6800.
Can we expect to get less cpu usage with future playback filters? Should I not use some of the x264 features for HDTV?
My Cli
--ref 3 --subme 6 --bframe 2 --weightb --b-pyramid --8x8dct --analyse all

Is it ok to use Nero AAC with 5.1 and VBR normal or it better to use cbr here?