I upgraded an old PC and use it to rip BDs

[jagabo]

The regular mediacoder has CUDA too.

[barkinglama]

I have the CUDA version now and it says it's working at 20-30FPS I will take a note of how long it takes to convert to ipad 720p format output file is 10GB

Well it took 3 hrs 50 mins, will have to try out the file streaming through the BD player tomorrow.

[deadrats]

I'm still figuring out all the details but I'm not all that impressed. I made a mistake about which card I had, it's an 8600 GT, not a 9600 GT. I am seeing 80+ fps encoding a 720x480 DVD source with CUDA (no filtering). But the lowly A64 X2 is getting about 30 fps with x264 (medium preset). I've been using the "variable bitrate" mode but the quality slider doesn't work with the CUDA encoder. I had to manually adjust the I/P/B quantizers in the advanced CUDA settings (the default values were horrendous). Quality appears to be OK once I adjusted the quantizers, but I haven't compared closely with x264 encodes yet. The mediacoder app itself is full of bugs. I can't make MKV files -- it complains about a missing ZLIB1.DLL. I didn't see any way to set the PAR/DAR when encoding from a AviSynth script.

a couple of things come to mind:

vbr doesn't seem to work with cuda encoder in media coder but abr (average bit rate) does, try that instead.

re: ZLIB1.DLL

http://www.mediacoderhq.com/forum/viewtopic.php?f=3&t=688

that should fix that problem, basically stan neglected to include a handful of libraries.

you can set the par/dar under the "picture" tab.

re: performance - you're getting 2.5x faster encoding with a bottom of the line video card and you're complaining? the reality is that frame serving from avisynth effectively makes your cpu the bottleneck as the card has to wait for the cpu to get the data to it. add in the small frame buffer (what does that card have, 128mb or 256mb?) and the slow video card ram (i'm guessing gdd2?) and i'm surprised that you're seeing the frame rates you are.

download gpu-z and check to see how much of a load the video engine, gpu, ram and card memory controller are seeing, if they aren't being pushed too hard you will probably find that using the gpu accelerated filters will essentially be "free".

why do you encode to mkv and not m2ts?

[jagabo]

vbr doesn't seem to work with cuda encoder in media coder but abr (average bit rate) does, try that instead.

I'm not interested in bitrate based encoding. I want to know that whatever video I encode it will come out with the quality I want.

re: ZLIB1.DLL

http://www.mediacoderhq.com/forum/viewtopic.php?f=3&t=688

that should fix that problem, basically stan neglected to include a handful of libraries.

Thanks. I managed to find it the night before and MKV output is now working.

you can set the par/dar under the "picture" tab.

Yes, I found that too.

re: performance - you're getting 2.5x faster encoding with a bottom of the line video card and you're complaining?

Yes. That dual core system can encode faster, with better quality, and smaller file size than MediaCoder with CUDA if I use the x264 CLI encoder and faster (than "preset=medium") settings.

the reality is that frame serving from avisynth effectively makes your cpu the bottleneck as the card has to wait for the cpu to get the data to it.

Not at all. Note that the 80+ fps was when opening a VOB file directly in MediaCoder. Opening the VOB via an AviSynth script (DgDecode) in MediaCoder was indeed much slower but that appears to be MediaCoder problem. As noted, using the same script and the x264 CLI encoder I can encode faster than MediaCoder+CUDA on that same machine.

add in the small frame buffer (what does that card have, 128mb or 256mb?) and the slow video card ram (i'm guessing gdd2?) and i'm surprised that you're seeing the frame rates you are.

download gpu-z and check to see how much of a load the video engine, gpu, ram and card memory controller are seeing

It's a 256 MB card. GPU-Z while encoding showed memory usage to be about 70 MB, GPU load near 100 percent. I don't remember what the memory controller load was but it was very low, barely a blip in the graph.

Now that I've had a bit more time to play with MediaCoder/CUDA I've found it's still lacking. To get comparable file sizes to x264 at CRF 20 I had to set the IPB quantizers to 22, 24, 26 respectively. It then delivered inferior picture quality. (The x264 CRF encoding had average quantizers of 18,20,22).

Even with small quantizers (and 2x larger file sizes) the CUDA encoder is displaying I frame beating -- ie, a GOP starts out with a high quality I frame and picture quality degrades over subsequent B and P frames. Then another I frame comes along and the picture quality suddenly clears up. Only to degrade again. The default I frame interval of 15 frames makes this very noticeable (~ 2 beats per second). I can increase the I frame interval to a larger value to make the beats happen less frequently but at the cost of overall picture quality.

Using Average Bitrate encoding was similar. At similar bitrates CUDA is delivering inferior quality. It takes about twice the bitrate to get similar quality as x264 CLI. Even then, the I frame beating is annoying.

I'll keep playing with the program to see if I can improve matters any -- in case the videos I was working with were somehow unusual or there was some other default setting causing problems.

My preliminary conclusion: although CUDA h.264 encoding has improved since the last time I looked at MediaCoder (at least a year ago), it's still unacceptable. Any speed advantages (when using a faster GPU) of CUDA come from bypassing the stuff that makes h.264 encoding superior.

[barkinglama]

why do you encode to mkv and not m2ts?

It was the first container I tried as I had read that it was supported by my devices, which it is to a limited extent.

What is the advantage of m2ts?

I have downloaded DVDFAB and will give it a go.

I am looking to end up with an avi file as that is the one all my devices will stream.

Cheers for the help

[deadrats]

What is the advantage of m2ts?

it's blu-ray compatible.

[deadrats]

Yes. That dual core system can encode faster, with better quality, and smaller file size than MediaCoder with CUDA if I use the x264 CLI encoder and faster (than "preset=medium") settings.

let's put that assertion to the test, remember that thread recently where the OP posted this really high quality mpeg-2 clip (encapsulated in an mp4 container)? give me the link to that file (i can't find the thread), we'll encode it to 720x576 16:9, h264 with ac3, 25 fps, m2ts, 4mb/s, you use x264 (any settings you want), i'll use media coder+cuda, we'll each report the frame rates and upload the results for comparison.

It's a 256 MB card. GPU-Z while encoding showed memory usage to be about 70 MB, GPU load near 100 percent. I don't remember what the memory controller load was but it was very low, barely a blip in the graph.

now that's interesting, with 64 cuda cores and 256mb worth of video ram the gpu load is 100% with 70mb video ram used but on my system with 128 cuda cores and 1024mb video ram the gpu load is only 40% and 170mb video ram used yet you get 80fps and i get 170-190fps. wish i knew exactly what was taking place behind the scenes.

Now that I've had a bit more time to play with MediaCoder/CUDA I've found it's still lacking. To get comparable file sizes to x264 at CRF 20 I had to set the IPB quantizers to 22, 24, 26 respectively. It then delivered inferior picture quality. (The x264 CRF encoding had average quantizers of 18,20,22).

then why not try the same quantizers with cuda and compare again?

[jagabo]

Now that I've had a bit more time to play with MediaCoder/CUDA I've found it's still lacking. To get comparable file sizes to x264 at CRF 20 I had to set the IPB quantizers to 22, 24, 26 respectively. It then delivered inferior picture quality. (The x264 CRF encoding had average quantizers of 18,20,22).

then why not try the same quantizers with cuda and compare again?

I originally used the same quantizers. The CUDA file turned out twice as large. And had the I frame beating problem. That's what this was about:

Even with small quantizers (and 2x larger file sizes) the CUDA encoder is displaying I frame beating