need encoding tips for better quality PS3-friendly MP4

[spicediver10191]

I'm creating an MP4 for distibution that I want to keep PS3 friendly.

Using a PS3 preset in Staxrip, I'm doing a very slow 2000kbps 2-pass encode from a good MPEG-2 PAL source.

While the quality is quite good, I've seen better.

Beyond having a max. of 3 reference frames for PS3 compatibility, I don't understand x264 encoding very well. Are there any perimeters under "Analysis", "Frame Options" or "Rate Control" that I can adjust to improve video quality without compromising PS3 playback? (p.s I don't have a concole to test on, unfortunately).

Thankyou!

[davexnet]

Bit rate constrained? What's the resolution?

[spicediver10191]

Bit rate constrained? What's the resolution?

It's full standard definition PAL resolution (720 x 576, same as the DVD source).

By bitrate constrained, do you mean have I set the target bitrate? Yes, at 2000kbps which I expected should be enough.

Specifically, what I'm seeing with the encoded file - in some scenes - is that familar MPEG-4 blotchiness/pixilation in areas of the picture where there's low contrast, ie. slight gradients of one colour. It was common with Xvid, less so with x264, but I'm hoping to be rid of it completely. It's certainly not in the source.

[guns1inger]

Try doing a Constant Quantizer encode with a value of 20 and see if you get better results.

[spicediver10191]

Try doing a Constant Quantizer encode with a value of 20 and see if you get better results.

Tried CQ 20, CQ18, and even a 2500kbps 2-pass. All no better quality than my 2000kbps 2-pass mp4.

Looks like I might have the maximum quality I'm going to get from this source? Just wish I could get rid of the slight blotchiness and pixilation in low contrast areas...

[guns1inger]

I would try a different front-end. I suspect StaxRip is setting something in the config of the encode that is causing your grief. I have been using XmediaRecode to convert DVD Video to MP3 for PS3/WDTV playback, and I am not getting those sorts of issues, even when using lower bitrates (1500 - 1800 kbps)

[spicediver10191]

I would try a different front-end. I suspect StaxRip is setting something in the config of the encode that is causing your grief. I have been using XmediaRecode to convert DVD Video to MP3 for PS3/WDTV playback, and I am not getting those sorts of issues, even when using lower bitrates (1500 - 1800 kbps)

Thanks. I'll try some alternatives and start experimenting.