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  1. Originally Posted by usually_quiet View Post
    Is the two-channel audio you are concerned about recording the two-channel audio available from HDMI, with 5.1 channel audio being available simultaneously via TOSLINK? If so, the 2-channel HDMI audio isn't present in the broadcast. The satellite box is down-sampling from 5.1 channels in the recorded broadcast to 2 channels for HDMI output.
    Yes, that's exactly what I was concerned about, but no longer given your explanation.

    So now I've got to go out and get a > 6ch audio-capable HDMI video capture card and a TOSLINK to HDMI converter OR this: In my research this morning, I found another option from Blackmagic. Their highest-end capture card, the DeckLink 4K Extreme 12G https://www.blackmagicdesign.com/products/decklink/techspecs/W-DLK-25 actually has 2 TOSLINK input/output ports, something the Aja KONA line doesn't have. Of course I worry about A-V sync issues with either option. They're both $1500 capture cards, so I'd hate to be stuck with an expensive lemon.

    Does anyone here have any experience with either Aja or Blackmagic customer support? I've seen a few posts here and there about Blackmagic support being iffy, although they seem to respond OK in their forum.
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  2. Keep in mind that ATSC tuners are only for over-the-air broadcast. They will not work with cable TV. For cable TV (in the USA) you need a QAM tuner. Cable companies are now allowed to encrypt whatever they want and mark the transmission as record-once so you'll need a CableCard enabled device. Encrypted record-once recordings are only viewable on the device that recorded them. On our cable system only a few channels (mostly OTA channels) can be freely copied.
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  3. And I assume there's nothing similar to qAM and Cablecard that can be used to record a DirecTV satellite signal directly onto a computer hard drive through a coaxial cable?
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    Originally Posted by end-user View Post
    [Their highest-end capture card, the DeckLink 4K Extreme 12G https://www.blackmagicdesign.com/products/decklink/techspecs/W-DLK-25 actually has 2 TOSLINK input/output ports, something the Aja KONA line doesn't have. Of course I worry about A-V sync issues with either option. They're both $1500 capture cards, so I'd hate to be stuck with an expensive lemon.
    The ultra high-end devices from Black Magic and Aja KONO are beyond overkill for recording the output of a DVR, plus you do not have sufficient background to make use of them. Case in point, the Decklink 4K Extreme 12 G doesn't have Toslink connections. It allows using two optional optical fiber modules for Dual Link optical fiber SDI input and output.

    Originally Posted by end-user View Post
    And I assume there's nothing similar to qAM and Cablecard that can be used to record a DirecTV satellite signal directly onto a computer hard drive through a coaxial cable?
    No. For the US market there are only DVB-T2 cards, which would allow recording unencrypted satellite broadcasts, but they don't work for paid services like DirecTV.
    Last edited by usually_quiet; 20th May 2017 at 12:58.
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  5. Originally Posted by usually_quiet View Post
    The ultra high-end devices from Black Magic and Aja KONO are beyond overkill for recording the output of a DVR, plus you do not have sufficient background to make use of them. Case in point, the Decklink 4K Extreme 12 G doesn't have Toslink connections. It allows using two optional optical fiber modules for Dual Link optical fiber SDI input and output.
    OK, thanks for pointing that out.

    But I'm wondering if those higher end cards (which have bells & whistles I won't need and don't know how to use) may cause me fewer frustration issues with dropped frames, A-V sync etc just because they "have more horsepower" for the level of video and audio I'll be working with coming out of the DVR. Any legitimacy to that theory?

    I'm also having a renewed interest in the Magewell cards you mentioned in your original post. They even have a FOUR HDMI input card (http://www.magewell.com/pro-capture-quad-hdmi) that they claim will process 4 HDMI inputs at the same time. Do you think my system would be able to handle that or am I just asking for trouble and frustration by trying to do too much at once? [Just as a reminder, here are my system specs: Intel chip i7-6950X Extreme 10 core with hyperthreading overclocked to 4.2GHz, 64 GB RAM (8x8 DDR4 2800MHz), video card 11GB NVIDIA GE Force 1080TI, 8TB HDD with RAID 1 mirroring, capable of expanding to max of 192 TB HDD, Windows 10 Home Edition.]

    And even if I only used 1 of the 4 HDMI input ports, does it look like this Magewell card can handle recording the 5.1ch audio?
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    Originally Posted by end-user View Post
    But I'm wondering if those higher end cards (which have bells & whistles I won't need and don't know how to use) may cause me fewer frustration issues with dropped frames, A-V sync etc just because they "have more horsepower" for the level of video and audio I'll be working with coming out of the DVR. Any legitimacy to that theory?
    No. Buying a top-of-the line "lossless" capture device won't automatically fix dropped frames and A/V sync. For example, when a hard drive or a CPU (these cards depend on software for encoding) can't keep up with the amount of data being fed to it, dropped frames result.

    Originally Posted by end-user View Post
    I'm also having a renewed interest in the Magewell cards you mentioned in your original post. They even have a FOUR HDMI input card (http://www.magewell.com/pro-capture-quad-hdmi) that they claim will process 4 HDMI inputs at the same time. Do you think my system would be able to handle that or am I just asking for trouble and frustration by trying to do too much at once? [Just as a reminder, here are my system specs: Intel chip i7-6950X Extreme 10 core with hyperthreading overclocked to 4.2GHz, 64 GB RAM (8x8 DDR4 2800MHz), video card 11GB NVIDIA GE Force 1080TI, 8TB HDD with RAID 1 mirroring, capable of expanding to max of 192 TB HDD, Windows 10 Home Edition.]

    And even if I only used 1 of the 4 HDMI input ports, does it look like this Magewell card can handle recording the 5.1ch audio?
    I have no idea if your PC can handle the load in all respects.

    The tech specs say the Pro Capture Quad HDMI can capture 8-channel audio, but software that can capture video using lossless codecs and 5.1 channel audio from the card is the missing piece of the puzzle. For example, much of the software that is compatible with the Magewell cards is geared towards streaming video and audio over the Internet. Maybe some of this software would be able to capture 5.1 channel audio, but would it allow encoding to a lossless video format, rather than one of the video formats commonly used for Internet video?

    I have not heard of any software that will do what you want. Maybe someone else has.
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    I sense creeping Analysis Paralysis. Why don't you pick one of the options and buy from some place like B&H that has a generous return policy? If you can't figure out how to work it or you have sync problems or your hairline recedes then you can send it back.
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  8. Ha! Yes, it's probably getting to the point where I need to "take the plunge." And I am planning to make some phone calls tomorrow. But I do want to dive into the right pool!

    One thing that concerns me about the Magewell cards is that they seem to pride themselves on the fact that their cards don't use any of the computer's CPU power. "Hardware-based video processing requires ZERO CPU Usage" http://mobilevideodevices.com/wp-content/uploads/2016/10/HDMI.pdf I've got a machine with 20 cores and an 11GB state of the art video card that was just released NVIDIA 2 months ago. Don't I WANT the capture card to tap into these resources?

    Another unrelated question: Is VirtualDub now considered dead-end video editing software by the community? I notice it hasn't been upgraded in 3 years and the forum disappeared 2 years ago.
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    Originally Posted by end-user View Post
    One thing that concerns me about the Magewell cards is that they seem to pride themselves on the fact that their cards don't use any of the computer's CPU power. "Hardware-based video processing requires ZERO CPU Usage" http://mobilevideodevices.com/wp-content/uploads/2016/10/HDMI.pdf I've got a machine with 20 cores and an 11GB state of the art video card that was just released NVIDIA 2 months ago. Don't I WANT the capture card to tap into these resources?
    The "hardware-based" processing they are talking about doesn't include encoding. With some software, there is also the option to use GPU-based encoding like Intel QuickSync and NVIDIA NVENC, performed by the CPU's integrated GPU or the GPUs on discrete graphics cards. However it is restricted to the supported lossy codecs. Lossless encoding is CPU-based.

    Originally Posted by end-user View Post
    Another unrelated question: Is VirtualDub now considered dead-end video editing software by the community? I notice it hasn't been upgraded in 3 years and the forum disappeared 2 years ago.
    I have a vague memory that Virtualdub's author had announced he was working on a complete re-write of his software before the forum shut down, but I have seen no reports about how much progress has been made on that project.
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  10. Originally Posted by usually_quiet View Post
    With some software, there is also the option to use GPU-based encoding like Intel QuickSync and NVIDIA NVENC, performed by the CPU's integrated GPU or the GPUs on discrete graphics cards. However it is restricted to the supported lossy codecs. Lossless encoding is CPU-based.
    Actually NVEnc supports lossless AVC encoding (--lossless) but only for 8bit 4:2:0




    Originally Posted by end-user View Post
    Another unrelated question: Is VirtualDub now considered dead-end video editing software by the community? I notice it hasn't been upgraded in 3 years and the forum disappeared 2 years ago.
    shekh has continued a branch of vdub, virtualdub filter mod . Actively maintained and updated

    https://sourceforge.net/projects/vdfiltermod/
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  11. Originally Posted by poisondeathray View Post
    Actually NVEnc supports lossless AVC encoding (--lossless) but only for 8bit 4:2:0
    Isn't that exactly the type of video I would be working with? If so, would I gain any benefit by having the GPU do most of the encoding work?

    poisondeathray: thanks for the link. I'm downloading it now. Nice to know VirtualDub is alive and well!

    Does anyone know if OBS or VirtualDub + or - AVISynth will allow me to losslessly capture 5.1 ch sound along with the video via HDMI? Or would I need to purchase a paid program like Adobe Premier Elements?
    Last edited by end-user; 21st May 2017 at 12:45. Reason: Clarity
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    Typically GPU-based encoding is faster. Historically GPU-based lossy encoding has produced lower-quality output than CPU-based lossy encoding, but the gap has narrowed over time.

    However, given identical input in each case, there should be no difference in quality between the output from different lossless encoders, because they are lossless. The size of the capture files could differ between lossless encoders.
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  13. Originally Posted by end-user View Post
    Originally Posted by poisondeathray View Post
    Actually NVEnc supports lossless AVC encoding (--lossless) but only for 8bit 4:2:0
    Isn't that exactly the type of video I would be working with? If so, would I gain any benefit by having the GPU do most of the encoding work?
    (My bad, actually it supports 4:4:4 too) . Eitherway it should support whatever you are sending through the HDMI, 8bit 4:2:0, 4:2:2 or 4:4:4

    The theoretical benefit is lower CPU usage. In my experience, GPU encoding can be "flaky" . It depends on the input and decoder, and in your case how you have the HW=> GPU/software setup. There are documented issues with mixed up frames , or framecount discrepancies like dropped frames for full GPU decode/encode unless input is indexed or software decode . I can replicate and demonstrate these errors easily, and they seem to be linked to the decoding side. But decoding doesn't affect you if you're feeding it uncompressed stream (you're not GPU decoding). And there should be fewer problems with pure intra (I-frame) mode. I don't know if NVEnc supports long GOP lossless, but it's simple enough to test, but long GOP lossless will offer better compression at the expense of slower seeks. But I suspect you should be ok if you can get the HW setup properly to feed NVEnc (I think OBS has NVEnc lossless option). But I would do some tests first , check for dropped frames etc.. before committing

    One negative is not all software supports lossless AVC decoding; many commercial editors don't for example
    Last edited by poisondeathray; 21st May 2017 at 13:34.
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  14. Thanks usually_quiet and poisondeathray for those informative explanations. Your efforts are much appreciated

    Originally Posted by usually_quiet View Post
    Audio capture with the Magewell Pro Capture HDMI is limited to 2-channels stereo when capturing video with any of the supported software. (The audio source is HDMI.) You would probably need to write your own software to capture video and multi-channel audio simultaneously. According to a post written by someone here who owns the Magewell Pro Capture HDMI, he was only able to capture multi-channel audio using sample code provided in the SDK, but the sample code doesn't capture video at the same time.
    Originally Posted by jaibubwan View Post
    I actually bought this last month (the "pro" 1 channel model, ie. single HDMI input).
    I inadvertently discovered its multichannel audio capability...while recording a live internet video stream that delivered 5.1 audio.
    I played back the recording on my computer, and various parts of the video were missing certain dialog & sounds.

    Then it hit me. In the capture card properties, it displayed all the channels of audio.
    But no matter what recording software I used (MageWell, OBS, XSplit)...they are all limited to recording 2 channel audio.
    Like the quoted user says, the card has the capability...and there's a little app for recording multichannel audio...but it's useless unless you can time the video & audio to record at the same time.
    Originally Posted by usually_quiet View Post
    The tech specs say the Pro Capture Quad HDMI can capture 8-channel audio, but software that can capture video using lossless codecs and 5.1 channel audio from the card is the missing piece of the puzzle. For example, much of the software that is compatible with the Magewell cards is geared towards streaming video and audio over the Internet. Maybe some of this software would be able to capture 5.1 channel audio, but would it allow encoding to a lossless video format, rather than one of the video formats commonly used for Internet video?

    I have not heard of any software that will do what you want. Maybe someone else has.
    I was just reviewing the thread, and no matter how great the hardware, the limitation is clearly the lossless compression and recording software. We've even got jaibubwan's tried and true user-verified confirmation of this with his Magewell card + OBS (and other software). It just seems that there MUST be a way to do this. I just don't feel that wanting to losslessly record HD video + 5.1 audio simultaneously via HDMI is that radical of an idea.
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    Should also point out that many times the 5.1 mixed audio is really simply made from a Stereo source (feed over satellite usually), which has been up mixed to 5.1 by the local OTA station. While this fake 5.1 is still 5.1 but does nothing to improve the experience and might even hurt the original Stereo quality (however minor). Hollywood movies and more recently made TV Shows (sitecoms, action, scifi, and so on) on your local stations are more likely to have an original 5.1 or higher mix but News programs, Documentaries, and even many reality TV programs are more likely to just be stereo audio, which is then remixed to 5.1 by the local station. This type of thing happens on pay tv also.

    I can only guess their reasoning for doing it is so that they can support 5.1 content while also not causing issues for the viewer, when the audio feed swaps between Stereo and 5.1 at the drop of a hat. So instead they just do 5.1, all day every day for a particular channel.
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  16. Okay, that's interesting. I have some 1970s era Midnight Special DVDs I purchased a few years ago that I want to transfer that also have a separate stereo track and a 5.1 track I can choose from, even though they were originally recorded in the 1970s (presumably in mono) and there was no such thing as 5.1 recording in the 1970s. I always wondered how it was that these DVDs came with a 5.1 audio track. It must be fake engineered 5.1 like you're describing, huh?
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  17. Yes, it's usually fake 5.1. But sometimes they have access to the original multitrack tapes (and a big budget) and can create some real effects. I usually listen to the original stereo or mono track.
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    Originally Posted by end-user View Post
    It just seems that there MUST be a way to do this. I just don't feel that wanting to losslessly record HD video + 5.1 audio simultaneously via HDMI is that radical of an idea.
    You may or may not be able to do this by building Direct-Show filter graphs with GraphEdit, GraphStudio, or similar software. These programs are software development tools, but they provide a way to capture and display video without actually writing software. However, success depends on how well the filters supplied by the capture device's drivers were designed (sometimes the driver filters simply don't provide access to the device settings that you need to configure) and what other filters installed on the system by other software can be re-purposed. ...and the audio and video encoders and decoders used need to be direct-show compatible.

    It isn't especially easy to learn how to build filter graphs, and it can be frustrating. There is usually some trial-and-error work involved in finding filters that work together so the graph can be completed.
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  19. My experience with Blackmagic support.

    Regarding the audio capture, why do you need to involve TOSLINK? The DirecTV box can't output decoded LPCM 5.1 or bitstreams over HDMI?

    Some people have had success tricking some BMD cards into capturing DD & DTS bitstreams. You wouldn't get any support for this though.
    https://forum.videohelp.com/threads/376473-Lossless-HDMI-capture-devices-comparison-sc...ts#post2454754
    https://forum.videohelp.com/threads/332189-HDMI-device-that-can-capture-%28unencrypted...e3#post2481632

    There is a Korean card called SkyDigital SKYHD CaptureX that officially supports AC3 & DTS via HDMI and optical, with uncompressed HDMI. I'm sure you're limited to their own software, though.
    http://www.digitalnow.com.au/CaptureX_HDMI.htm
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  20. First of all, usually_quiet, thanks for that great info as a potential workaround. And thanks for every other informative post you've made in this thread. I have learned a lot from you.

    vaporeon, honored to have you add your highly respected expertise to the discussion!

    Originally Posted by vaporeon800 View Post
    Gee...that exchange doesn't exactly inspire confidence in Blackmagic support, especially when the issue is low quality video, something you'd expect to be no problem for the IP4K. Did you ever get the issue resolved after she escalated it?


    Originally Posted by vaporeon800 View Post
    Regarding the audio capture, why do you need to involve TOSLINK? The DirecTV box can't output decoded LPCM 5.1 or bitstreams over HDMI?
    I always assumed that audio output from a DVR was cut & dried: HDMI always carries 2ch PCM stereo, TOSLINK always carries an AC3 bitstream. If this is not the case, how would I be able to tell exactly what kind of audio ACTUALLY IS coming out of the DVR via HDMI?


    Originally Posted by vaporeon800 View Post
    There is a Korean card called SkyDigital SKYHD CaptureX that officially supports AC3 & DTS via HDMI and optical, with uncompressed HDMI. I'm sure you're limited to their own software, though.
    http://www.digitalnow.com.au/CaptureX_HDMI.htm
    Hmmm...fascinating. The card seems to have what I want it to do. The limitation to a max resolution of 1080i isn't an issue, because network OTA broadcasts are NOT in 1080p. I could always get a 2nd capture card if I ever did want to record in 1080p or UHD, where 5.1 wouldn't be an issue. Do we know if the software is any good, whether there are A-V sync issues, dropped frames etc. And once the uncompressed video/5.1ch audio file is on my computer, can that file be losslessly compressed or will we run into the same issue of the 5.1 being downsampled to 2 ch stereo by the lossless compression software? Do we know how long it's been on the market? Or where I would even find one?

    A further search shows that Skydigital has an EXTERNAL USB card that captures up to 1080p30 + "Real-time multi-channel digital audio capture" http://www.ebay.com/itm/Skydigital-CaptureU3-0-HDMI-1080p-External-Video-Capture-Card-...717?rmvSB=true Would this work for my purposes, which is lossless recording of HDMI video + 5.1 audio from my DirecTV DVR?
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  21. There's no 30p video broadcast in the USA. So if that card deinterlaces everything you'll be losing half the temporal resolution and maybe half the spacial resolution.
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    Originally Posted by end-user View Post
    A further search shows that Skydigital has an EXTERNAL USB card that captures up to 1080p30 + "Real-time multi-channel digital audio capture" http://www.ebay.com/itm/Skydigital-CaptureU3-0-HDMI-1080p-External-Video-Capture-Card-...717?rmvSB=true Would this work for my purposes, which is lossless recording of HDMI video + 5.1 audio from my DirecTV DVR?
    I don't think this particular device de-interlaces 1080i60 to 1080p30, but multi-channel audio capture might not be straightforward.

    See: https://forum.videohelp.com/threads/358957-How-to-capture-DD-AC3-audio-with-Skydigital-CaptureU3-0

    It is possible that the documentation and software may not be provided in English, only Korean.
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