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2009-12-19 02:53

V-12

Registered: Nov 2003
Posts: 206

Tutorial for capture'n'encode video from real C64

Hello!
Is there anywhere any tutorial step by step to explain how to:
1) record a video with music of course using PC TV card and C64 connected via s-video cable (which program is the best for it, eventually configurations?)

2) encode the video with deinterlace (or if I'm wrong, just help) - which program, how to use step by step.

Tutorial like this would help more people with recording stuff from real C64.

I've tried to record the video using Winfast PVR and DScaler. First one has no smooth scrolling (maybe deinterlace encoding needed or I dunno?) and second one strangely has bad video quality output.

If anyone could support me with any quideline how to properly record and encode videos from C64 it would be appreciated. Maybe is there any guideline on web?
Thanx in advance!

... 4 posts hidden. Click here to view all posts....

2009-12-19 14:24

wacek

Registered: Nov 2007
Posts: 501

my advice will be bit different than Groepaz ;)

- don't use videocards with tv tuners. use something that can do a/d video conversion outside of computer :)
- don't deinterlace. keep your 50hz interlace in place for all those smooth scrollers :)
- for encoding, go for lossless compression or high quality PERCEPTUAL codecs. then output to high quality final stream, my weapon of choice is good old mpeg2 with finetuned settings :)

my method (of which i will write more soon), gives the below quality:

for my taste this is quite good, remember we're dealing with >20yrs old hardware built for SD resolutions.

oh, and talking singlepixel effects?

what do you think? but don't go zooming the images looking for flaws (they are surely there), tell me what do you SEE when looking at those screens :)

2009-12-19 14:57

V-12

Registered: Nov 2003
Posts: 206

The quality of yours screenshoots are amazing! We can see the pixels very clearly :D

2009-12-19 15:10

assiduous
Account closed

Registered: Jun 2007
Posts: 343

Quoting wackee

keep your 50hz interlace in place for all those smooth scrollers :)

theres no interlace in the c64 video. its 288p,all fields should be drawn progressively. the reason why many programs handle it wrong is that they`re usually suited for a regular tv stream which is 576i. for example dscaler may display a 50fps if you choose a correct method but it will save a 25fps video with merged frames anyway so a little bit of postprocessing is required to restore the original framerate.

2009-12-19 15:31

wacek

Registered: Nov 2007
Posts: 501

I never wrote that C64 video is interlaced :)

What I wrote was that to properly contain 50fps in a non-prof environment it's best to simply use PAL interlaced for capturing. Then you don't need ANY postprocessing to have proper 50 frames C64 video in your output stream, just encode interlaced - the output will be progressive-scanned to 50fps for the beamer or LCD tv or whatever by the dvd player.

On the other hand, if you go 50fps progressive, you have problems with most video hosting sites like vimeo or youtube, because they do not handle 50fps properly.

Also, I support your suggestion to do not convert between colorspaces when processing ;)

Agreed?

2009-12-19 18:18

lemming

Registered: Oct 2009
Posts: 44

Hi everyone,
I was referred to this topic by Grue/BF 'coz I'm not active on these forums.. so thanks to him. :)
I've done numerous caps (some of them can be watched on http://youtube.com/lemmingiFIGation) and apparently a few of you might be interested in some tips on how to do this.

First of all, build yourself an SVideo-cable that fits the C64 A/V output. I've found out that using a ~300ohm resistor on the chroma-pin gives the best possible quality on C64/C64E/C16/C128D, because it eliminates the 'checkerboard' effect which is visible on digital displays. (I myself have soldered such a resistor to the insides of all my CBMs except for the VIC-20 which has only video out, thus not capable of SVideo).

For the capture use a quality DVR (I personally use a Sony HDR-HXD870) or an analog MPEG2 capture card which can handle 50fps and rapid movement somewhat losslessly. MPEG2 can be captured with excellent quality these days, so you'll have no real advantages with MPEG4 or a pure lossless codec such as HuffyUV.

The video you get from a C64 is 288 lines progressive, but since there are technically no progressive 288 line PAL-displays, you'll end up with 50Hz combed 576 line video. Kinda like watching VideoCD:s...

Anyway, as Wackee already stated, a separate A/D converting recorder is better. You'll get DVD-compliant proper 50Hz MPEG2 that way without hassling with capture software.
However you decide to do it, as you'll watch your caps on your PC's MediaPlayer/VLC/whatever, you'll most likely notice that the combed 50Hz video stutters terribly. This is something which does not occur if you watch with a hardware DVD-player. You might even want to compress the video to another codec, such as x264 like me.

Converting to progressive 25fps does not help - the video movement will still stutter: PAL C64 video has to be 50fps. You're gonna need to make 50fps progressive video, and for that you'll need some software to encounter this issue properly.
The first one is AviSynth (google it up).
The second one is an external compressor, perhaps you wanna do x264 like me or perhaps you wanna make an MPEG2 transcode, whatever. I personally use MeGUI as a frontend for x264. (google it up as well)
The third one is dgindex for making an index file of the MPEG2/VOB you've captured (might not be required if using a TV-cap card). (still more googling)

Run the VOB-file through dgindex and you'll get a d2v file.
Create an AviSynth script (there's an AviSynth script creator in MeGUI if you don't know what you're doing and want to crop the borders (not the C64's SIDEBORDERS but the crap that an analog image has 'off-screen':) etc.. the cropped outcome has to be mod4 both horizontally and vertically (ie width/4 gives you an integer, not a float)
Next you gotta decomb the video while keeping it 50fps. This is the most important part! I'm sure there are many ways to tell AviSynth how to process this, but after a few days of playing around with AviSynth and various plugins such as McBob and SecureBob and whatever.. finally I came up with the following script, it's simple and beautiful and doesn't use any time- and CPU-consuming plugins:

ConvertToYUY2()
AssumeTFF()
SeparateFields()
odd=SelectOdd()
even=SelectEven().Crop(0,1,720,287).addborders(0,0,0,1)
interleave(odd,even)
spline36resize(720,576)

.. what it does basically is separating the combed lines to 288p from the capture, aligns the frames properly and brings it back to the full screen beauty of PAL 720x576.
After that you can add your crop parameters, such as
crop( 12, 2, -24, -6)

.. and you're ready to compress. Remember to tell your compressor FPS=50 just in case, and use high enough bitrate (or even better, experiment with your compressor's parameters to save a bit of bitrate and still keep the encode transparent) so you'll keep the wonderful image and movement of C64 transparent even after the encode.
So happy capping (digitizing!) and encoding to whoever this message might have been helpful to and sorry for not being able to keep it shorter ;)

Note: YouTube doesn't perfectly cope with progressive 50fps.. or a lot of other things.. here's a link to a sample mkv done with this process by yours truly: http://hotfile.com/dl/21183854/827048b/FIG-1988-CONTESTDEMO.mkv..

2009-12-19 19:18

assiduous
Account closed

Registered: Jun 2007
Posts: 343

heres an example 8 second video i made long ago to see if i could get the perfect quality:

http://rapidshare.com/files/323137242/x264-comp.avi.html

theres a frame drop at the beginning caused by the HDD stutter when I recorded the original material(YUV@173Mb/s). i compressed it with x264 down to about 22Mb/s.

dont download it if you dont have a FAST cpu.

2009-12-19 19:31

wacek

Registered: Nov 2007
Posts: 501

That's another thing. MPEG2 is more CPU-friendly, you don't need a monster-PC to watch it. Also, with good encoder and finetuned settings you can get awesome quality at VBR 5500kbit/s. But of course, there are many choices :)

2009-12-19 19:46

lemming

Registered: Oct 2009
Posts: 44

You don't have to go higher than 1500Kb/s with x264 or h264. (the above flick I've posted is 1300Kb/s)
The ability to decode h264/x264 with GPU has been existed on ATI/Nvidia/Intel-cards for a few years now, so no monster CPU is needed. You need to use Level 3.1 (standard definition) or Level 4.1 (high definition ie 720p/1080p) for 'hardware decoding' compliancy. This is done by telling the encoder to use a certain maximum number of reference frames, this is done by calculating 6750*1024/1.5/(X*Y)1 for SD where X=width-mod16 and Y=width-mod16, for example 6750*1024/1.5/(720*576)=11. 6750 is the MaxDPB for L3.1 , 12288 is the MaxDPM for L4.1.

MeGUI already has a number of 'DXVA'-profiles for x264 which have proper settings for these GPU-decoding compliant techniques, in case you don't know what you have to do.

2009-12-19 20:00

Mace

Registered: May 2002
Posts: 1799

wackee, please describe what hardware you're using to do A/D outside computer.

2009-12-23 07:58

wacek

Registered: Nov 2007
Posts: 501

I am using a camcorder with a/d interface, also by Sony, DCR-HC90. Back in 2005 when it was released it was really top of the line considering features - I wish I had at least half of those in my new Full-HD one (interval recording for example).

Anyway, it really does a good job for converting from analog to digital, and accepts s-video signal, not only composite. I have it hooked via firewire so I grab the captures directly on the go, without using the tape, with the data rate of 25Mbit/s. Right now this is the only job this camera is doing anymore - only C64 captures :)

Of course, there is also additional postprocessing after the capture.

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