AVS Forum banner

Capturing HD from Moto 3400 cable box

7K views 42 replies 10 participants last post by  Loobster 
#1 ·
Hi all, not been in here for a while.


I have been using a video converter (component in, s-vid out) and Magnavox DVD recorder for a while to record some shows off the cable box to MPEG2 (DVD).


Now we have a couple of WD TV Live media players and I have a networked PC storing/serving up video, I am converting a lot of MPEG2 material to Xvid to save on space. MPEG2 stuff that originally came from DVD looks great after conversion. But the stuff that came from cable > video converter > DVD Recorder > ripped to PC > converted from MPEG2 to Xvid - does not look so hot.


I have a media PC which sits behind the TV stack and is a quad-core Q6700, with 8GB RAM, 1TB drive and Windows 7 x64. At present there is no capture hardware, but I do have a PCI-E firewire card, if that helps.


I was hoping for some advice on what I could buy for the media PC to capture from the cable box (component out) to end up with files of good video quality on the media PC, at which point I can edit on my master PC upstairs (i7-2600k, 16GB, 128GB SSD+2TB spinny drive, Win 7 x64) and convert if needed to the final format (x264?).


I did a search on the forum and the Hauppauge 1212 is mentioned in a few places but that seems to be a few years old now and I was wondering if there is something better or more cost effective. My knowledge of PC hardware and software in general is very high but I've lost touch with current capture hardware options.


Looking to spend maybe up to $200-ish.


TIA!
 
See less See more
#27 ·

Quote:
Originally Posted by Loobster  /t/1456172/capturing-hd-from-moto-3400-cable-box#post_23324335


Ok great, thanks Kelson.


I was looking at a couple of downloaded mp4 and even some AVI files, and they are 640x400 (ish) and the bitrates are 1Mbit/sec or less ... but still look pretty good on the TV, and are 165-175MB for a 21 minute show or 320-350MB for a 42 minute show. How do they get such good PQ with such a low bitrate? Do they capture in HD then use better software to re-encode (maybe 2 or 3 pass) to get the quality so good?


I tried with 1.2Mbit and could not get the quality close to the download, but the filesize was much bigger.

Anyone got any comment on this question please?
 
#28 ·
They capture the original bitstream (bit for bit identical to the source) and then offline re-encode the content using variable bitrate/multipass (software) encoders.

OTOH You are using a realtime hardware encoder which takes the uncompressed video & audio signal and re-encodes it back to the compressed state to re-create a bitstream.

The best quality with your hardware will to be to capture at max-bitrate the hardware device allows you to select, and then offline re-encode to a lower bitrate & resolution with a software encoder.

You may not want to invest that kind of effort / time, or you may be satisfied with one of the profiles offered by your hardware device?
 
#29 ·
Thanks for that.


I'm willing to put plenty of CPU time into it (and to a certain extent, money for software) to achieve significantly better results, if anyone has any suggestions on what good transcoding software would be.


So basically capture in 1080i and software re-encode with multiple passes. It's kind of what I have done before with other stuff using Xvid (albeit not from a HD source), so I guess my new procedure should include x264 instead?
 
#30 ·
CRF mode doesn't require multiple passes, and while x264 can do multi-pass encoding, CRF mode produces superior results. Multi-pass encoding is used for XviD encoders, which don't have a CRF mode. The best H.264 encoder is x264, and it's thankfully FOSS. Recording from component output will always yield inferior results to using the original bitstream (in an absolute sense), but whether you could see a difference in the results is uncertain.
 
#34 ·
MeGUI is a nice front end to allow you to re-encode using x264. It's very powerful and flexible, but comes with a steep learning curve to take advantage. I'll use it on some encodes, particularly films if I want to perform IVTC since VideoRedo doesn't offer that option.
 
#35 ·
I'd suggest feeding x264's command line with AVISynth if you want advanced features like IVTC. I tried programs like MeGUI and found them even more difficult to use than the command line, as most of the free all-in-one solutions are rather cluttered. Avidemux has some decent features, but it's also buggy.
 
#36 ·
Ok. So after pretty extensive testing, I've come to the conclusion that the Colossus does as good of a job (or actually, a bit better) of capturing the video in lower resolutions on the fly (providing you hit the right capture settings) than if you capture in 1080i and then use Video ReDo to re-encode it.


I settled on 720x480 at 1.2Mbps for the stuff that I don't want to retain a HD copy of.


I guess there may be a chance that a more expensive program might do a better job of re-encoding the video, but I'm satisfied with the output I'm getting. Video ReDo does seem to re-encode pretty quick though .... I do wonder if there are better programs out there that might take longer but end up with better results.


Since I now just need something to splice commercials out and don't need to re-encode, is there a program that's cheap or free that will do that with M2TS or TS files? Video ReDo is ok, but the frame/scene navigation isn't anywhere near as good as other programs that I've used before (like the Womble products) although I wonder if MPEG2 material just lends itself better to easier navigation than AVC material.
 
#37 ·

Quote:
Originally Posted by Loobster  /t/1456172/capturing-hd-from-moto-3400-cable-box/0_100#post_23343718


Video ReDo does seem to re-encode pretty quick though .... I do wonder if there are better programs out there that might take longer but end up with better results.
Single pass encoding with VRD runs fast but doesn't look very good, in my estimation. When I played with re-encoding MPEG-2 TiVo or WMC captures to H.264, I edited the profile to do 2-pass encoding and the end result was very good (using only a 30% reduction in bitrate). If for some reason I ever had to re-encode my MPEG-2 captures to H.264, that is the way I would do it.
Quote:
Since I now just need something to splice commercials out and don't need to re-encode, is there a program that's cheap or free that will do that with M2TS or TS files? Video ReDo is ok, but the frame/scene navigation isn't anywhere near as good as other programs that I've used before (like the Womble products) although I wonder if MPEG2 material just lends itself better to easier navigation than AVC material.
What is it you don't like? You can see a row of frame thumbnails and you can set the interval to individual frames or timed from 0.1 to 60 sec -- I usually set mine to 0.1 sec unless I need a finer frame cut. You can customize the skip buttons and arrow keys to jump forward or back at a time interval of your choosing. I have my skip buttons set for 5 sec, 30 sec & 2 min and my arrow keys at 1 sec. You can get anywhere in the file very quickly. I think the commercial detection -- with the proper settings -- is outstanding and the batch mode lets me run a group of captures through the commercial detection without any attention.


But, of course it is not free.
 
#38 ·
It just doesn't seem to work very smoothly, and the interface isn't as good as others that I've used. So I am not dropping $100 on a product that isn't as good as what I've used before, software is supposed to get better, not worse.


I'm still searching for the product that's going to do it for me.


I thought AVS video remaker was going to be the one and it did edit without re-encoding, but the video/audio sync issues were horrific.
 
#39 ·
I found the software I am going to settle on.


It's FameRing's Smart Cutter. Cuts both 1080 and lower res captures from the Hauppauge card. I tested the trial version with a number of captures of different resolutions and it seems like it does a great job. Had no audio sync issues and obviously it doesn't re-encode. Frame accurate, so I don't end up with bits of commercials where the video is spliced out.


At $50, it's cheaper than alternative products, and is easy to use.


Thanks to all for their contributions to this thread.
 
#40 ·

Quote:
Originally Posted by Loobster  /t/1456172/capturing-hd-from-moto-3400-cable-box/0_100#post_23688426


and obviously it doesn't re-encode. Frame accurate, so I don't end up with bits of commercials where the video is spliced out.
Glad you found an editor you are happy with. But as far as encoding goes, if it is frame-accurate then it does encode -- it has to -- not the whole file, just locally around the cut points. Without local encoding it can only cut on a GOP boundary which comes every 1/2 second for MPEG-2. This is usually referred to a "smart encoding".
 
#41 ·
Are you sure that the I-frame interval is fixed to every 1/2 second? Even though H.262 is more primitive than H.263 and H.264, I would think that it would still allow for variable I-frame placement, which typically varies from 1 - 10x the framerate, i.e. keyframes will occur once every 1 - 10 seconds, depending on the encoder's preference. I would expect HD channels to have more frequent keyframes, whereas 480i sub-channels would likely use them less frequently, thus making accurate cuts without transcoding the boundaries more difficult.
 
#42 ·

Quote:
Originally Posted by Aleron Ives  /t/1456172/capturing-hd-from-moto-3400-cable-box/0_100#post_23689483


Are you sure that the I-frame interval is fixed to every 1/2 second?
I was just trying to keep it simple to make the point. The Video Redo OSD shows what kind of frame (I, P, B) you are cutting on so I'm conscious of frame-type as I edit. Yes, for broadcast OTA (MPEG-2) the I-frame interval can be longer/shorter than 0.5 sec and it depends on the station. 15 frames (0.5 sec) , seems to be a favorite interval, especially for commercials. I've occasionally seen it shorter than 15 frames and more frequently longer than 15 frames but rarely more than 30 frames (1 sec).


The point being that frame-accurate editing nearly always take place on a B or P frame and therefore requires local recoding around the cut point to re-establish the I-frame.
 
#43 ·

Quote:
Originally Posted by Kelson  /t/1456172/capturing-hd-from-moto-3400-cable-box/30#post_23689302


Glad you found an editor you are happy with. But as far as encoding goes, if it is frame-accurate then it does encode -- it has to -- not the whole file, just locally around the cut points. Without local encoding it can only cut on a GOP boundary which comes every 1/2 second for MPEG-2. This is usually referred to a "smart encoding".

I see, thanks for that clarification. If Smart Cutter does re-encode, it must only be a few frames, because I've watched an edited HD show and it's the same quality as the original. I can tell that it is just doing direct stream copy, because it resaves with just the commercials cut out, and it does it very quickly. It does pause for a second at each join point, but it literally is one second - I guess that's as long as it takes on my main PC to re-encode the frames it needs to at the join points. But I do have a powerful PC, i7-2600k, 16GB RAM, with an SSD for OS and programs (2TB spinny drive for data).
 
This is an older thread, you may not receive a response, and could be reviving an old thread. Please consider creating a new thread.
Top