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eatpills
8th February 2008, 07:52
I have some source material from a DVD recorder that is supposedly (more about this later) 720x480 MPEG2 interlaced. I get this using my usual method of creating an image of my DVD+RW, ripping to a single VOB using DVD Decrypter and editing out parts with VideoReDo.

I've accumulated a fair number of these files and I want to encode them to x264 to save space. I spent the last two days encoding using various options with MeGUI. However, I'm not quite happy with the result. Here are some of my issues:

a) Profile: So far, I've tried CE-Highprofile and HQ-Fast, which have failed to deliver the results I want. Which profile delivers quality within a reasonable time period?

b) Bitrate: I'm thinking that this is probably the source of my problem with quality and such. I've been using the default 1000kbps in the profiles I've tried. What are recommendations for 55min MPEG2 at ~4.5Mbps? My sources are about 1.8GB and I want to get it down to at least 60% of the original size.

c) Interlacing: At first, I was deinterlacing with AVISynth's TDeint(). Then I realized that x264 could also output interlaced video. I added the --interlaced switch to the additional command line options of the profile. Is this right? And is it a good idea to leave my material interlaced?

c) Resolution: I'm having some major problems here. My source is apparently 720x480, but something tells me that it might be 640x480 (despite many things telling me that it's the former). Now x264 gives me real 720x480 output and it looks weird (correct term is wrong aspect ratio, I think). Furthermore, when I take a snapshot of my source with VLC, I get an image that's 640x480...so it's probably this. How would I go about forcing a resolution of 640x480 in AVISynth or something?

Thanks for your help, and I hope to be doing quality encodes soon :)

Dark Shikari
8th February 2008, 08:11
) Profile: So far, I've tried CE-Highprofile and HQ-Fast, which have failed to deliver the results I want. Which profile delivers quality within a reasonable time period?TDeint is likely your bottleneck, not the encoding profiles. HQ-Slow isn't particularly slow at all with a good CPU, but TDeint is.
c) Interlacing: At first, I was deinterlacing with AVISynth's TDeint(). Then I realized that x264 could also output interlaced video. I added the --interlaced switch to the additional command line options of the profile. Is this right? And is it a good idea to leave my material interlaced?Interlaced encoding is less efficient than progressive encoding, and you'll have to deinterlace on playback anyways.
c) Resolution: I'm having some major problems here. My source is apparently 720x480, but something tells me that it might be 640x480Aspect ratio, most likely.

eatpills
11th February 2008, 04:53
Apparently my DVD recorder (or possibly VideoReDo) flags my video as 720x480 when it's really 640x480. I'm using Lanczos4Resize(640, 480) in my AVS as a quick fix for this.

As for interlaced encoding, how is it less efficient than progressive encoding?

As well, TDeint is inefficient (as you said), which will lengthen the encoding time -- and I have a huge amount of stuff to encode. I don't mind the extra CPU usage during playback -- it's not like I'm encoding high bitrate 1080p or something.

Since my last post, I've tried HQ-Slow @ about 1800kbps and I'm still not satisfied. I have another test going right now with HQ-Slower @ 2000kbps. I hope that turns out well.

Atak_Snajpera
12th February 2008, 21:48
As well, TDeint is inefficient (as you said), which will lengthen the encoding time -- and I have a huge amount of stuff to encode. I don't mind the extra CPU usage during playback -- it's not like I'm encoding high bitrate 1080p or something.


forget TDeint! Yadif is faster and don't have problems with artefacts. I really don't understand why TDeint is still used. If any deinterlacer gives artefacts/error it's useless.

Irakli
13th February 2008, 00:28
Apparently my DVD recorder (or possibly VideoReDo) flags my video as 720x480 when it's really 640x480. I'm using Lanczos4Resize(640, 480) in my AVS as a quick fix for this.

As for interlaced encoding, how is it less efficient than progressive encoding?

Interlaced encode requires higher bitrate than progressive encode to look the same (all other things being equal).

Also, if you're going to resize, deinterlacing before resizing is a must.

Blue_MiSfit
13th February 2008, 01:53
also, x264 is not good at interlaced encoding. It's not a design priority.

Deinterlace your video to either half or full rate before encoding. It's the only way to go!

~MiSfit

Dark Shikari
13th February 2008, 02:10
also, x264 is not good at interlaced encoding. It's not a design priority.Not entirely. Quite a lot of money went into x264's interlaced support ;)