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  1. I am looking again to professionally transfer recordings that have been recorded over the years via OTA antenna onto DirecTivo HD DVRs. I want to transfer them losslessly onto a very large computer hard drive. Compression is OK as long as it is lossless. I thought I had this problem solved with the Korean Skydigital SKY CaptureU 3.0 external capture card after a very thorough discussion in this thread from 2017 during which I learned a lot. This capture card worked for a while, but now it won't even display the video being inputted. I keep getting filter load and filter connect errors telling me that the driver may not be properly installed and to reinstall the driver. I have the last known driver and the company Skydigital and its website now appears to be defunct with no new drivers. Reinstalling the Skydigital capture software and drivers does nothing. The capture card worked on Windows Vista, but now I'm using Windows 10, so I assume that's the problem.

    I still have the same goal to transfer this recorded material. I am now recording OTA directly onto my HDD via a tuner card, which solves the problem going forward but doesn't help transferring the OTA material that's been recorded in the past, so unfortunately I'm kind of back to square one with this.

    Has any established company come out with a video capture card that records losslessly and also captures 5.1 audio? Or is there any other way to achieve my goal?

    And what's the latest on HDCP strippers? I have an older one, but I don't know if it strips the latest version or not. I'm just trying to strip HDCP off of OTA broadcast content, not copyrighted stuff.
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  2. Well...I take it that from the complete lack of response about this that it is still difficult or impossible to do this. usually_quiet, you've been unusually_quiet! And I wish vaporeon800 were still around. I just don't see why in 2019 I have to hire a video engineer to get this done.

    Anyone care to comment, even if it's that you've never heard of a capture card that can accomplish this with material that has already been recorded? I know that it can be done with tuner cards on live broadcasts (which I currently do as much as possible), but my issue is doing it with material from the past that's already been recorded.
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    Do you really need me to respond when all I can tell you is that I am unaware of anything new since 2017 that will allow you to easily capture 5.1 audio plus losslessly compressed video at the same time?

    The Magewell Capture Pro HDMI still teases the possibility of capturing 5.1 audio but I have found nothing so far indicating that anyone has written software that allows capturing both 5.1 audio and losslessly compressed video at the same time from an HDMI source with this device.

    Originally Posted by end-user View Post
    And what's the latest on HDCP strippers? I have an older one, but I don't know if it strips the latest version or not. I'm just trying to strip HDCP off of OTA broadcast content, not copyrighted stuff.
    There are no new threads listing new HDCP strippers here and I have the impression that some models that used to work now use different parts which don't support that feature or that they never did remove HDCP beyond HDCP 1.3.

    OTA content *is* copyrighted. The law merely grants consumers the right to record TV in order to watch broadcast TV at a convenient time.
    Last edited by usually_quiet; 23rd Apr 2019 at 16:03. Reason: HDCP strippers
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    See my previous answer in this thread, post 120 related to the magewell card.

    https://forum.videohelp.com/threads/383626-What-Is-The-Best-Lossless-Video-Capture-Car...Mid-2017/page4

    The only problem so far is I haven't been able to use any multichannel dolby hdmi embebbed version only lpcm or any DTS flavour both up to 7.1.
    Last edited by FLP437; 23rd Apr 2019 at 16:28.
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  5. Member Cornucopia's Avatar
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    The magewells have the capability in their sdk, but you'd have to build your own app. I thought the blackmagic devices had a similar capability, as I have seen a few references to links regarding multichannel audio capture with them when I googled it in the past.

    I'm guessing that those who really need MCaudio along with their HDMI video captures would probably get an HDMI de-embedder and output AES or mc analog to a dedicated pro audio capture card.

    Scott
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    NO need to do your own app based on the sdk , just use virtualdub2 and select the magewell wdm option under the audio menu, is that simple or use the other options.
    I have helped the virtualdub2 develloper to support the magewell card and it works fine.
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    Virtualdub2
    update 2 (build 40879)

    Capture mode changes:

    list more audio devices (helps with Magewell)
    fixed P210 support

    update 1 (build 40716)

    Capture mode changes:
    can select any video codec / any output format
    audio can have up to 8 channels
    "channel mask" option for audio
    panel shows important processing in effect
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  8. Member Cornucopia's Avatar
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    Alright!!

    Scott
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    Originally Posted by FLP437 View Post
    Virtualdub2
    update 2 (build 40879)

    Capture mode changes:

    list more audio devices (helps with Magewell)
    fixed P210 support

    update 1 (build 40716)

    Capture mode changes:
    can select any video codec / any output format
    audio can have up to 8 channels
    "channel mask" option for audio
    panel shows important processing in effect
    US HDTV broadcasts mostly use 5.1 channel Dolby Digital for the primary audio stream. end-user's DVR probably provides a choice between either 5.1 channel Dolby Digital output or 2-channel LPCM output for HDMI audio. I suspect that end-user wants to capture the 5.1 channel Dolby Digital as-is.

    In your other post in this thread, you said that capturing 5.1 channel Dolby Digital using the Magewell Capture Pro HDMI didn't work. Has that changed in Virtualdub2 update 2 (build 40879)?
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    I have not tested recently so I don't know if anything as changed, however I suspect that nothing have changed but I don't think it's a virtualdub2 related problem as with the other options magewell capture express 3.0, Graphstudionext I had the same problem, so more inclined to think that is some hdmi related problem ( edid ,etc ) dolby output hdmi vs S/PDIF or a card decoding problem. For sure now is the support to up to 8 LPCM or 8 DTS hdmi embedded channels .

    The statement from Magewell “Support for capturing of IEC60958/IEC61937 audio, including uncompressed audio such as 5.1 channel, 7.1 channel, DTS, THX, SRS and compressed audio such as AAC and MP3” is also not completely clear with regard to dolby.
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  11. Originally Posted by usually_quiet View Post
    Do you really need me to respond when all I can tell you is that I am unaware of anything new since 2017 that will allow you to easily capture 5.1 audio plus losslessly compressed video at the same time?
    Ha! I guess you're right, but it at least lets me know that you (or anyone else for that matter) have seen the post! By the way thanks for teaching me so much in that thread 2 years ago.

    Originally Posted by FLP437 View Post
    See my previous answer in this thread, post 120 related to the magewell card.

    https://forum.videohelp.com/threads/383626-What-Is-The-Best-Lossless-Video-Capture-Car...Mid-2017/page4

    The only problem so far is I haven't been able to use any multichannel dolby hdmi embebbed version only lpcm or any DTS flavour both up to 7.1.
    FLP437, I read your post in the other thread with great interest, but I don't understand what exactly the audio is that you are adding "up to 7.1" if its not the HDMI embedded Dolby digital AC3 stream.

    Originally Posted by usually_quiet View Post
    US HDTV broadcasts mostly use 5.1 channel Dolby Digital for the primary audio stream. end-user's DVR probably provides a choice between either 5.1 channel Dolby Digital output or 2-channel LPCM output for HDMI audio. I suspect that end-user wants to capture the 5.1 channel Dolby Digital as-is.
    Yes that's 100% correct.

    Originally Posted by usually_quiet View Post
    In your other post in this thread, you said that capturing 5.1 channel Dolby Digital using the Magewell Capture Pro HDMI didn't work. Has that changed in Virtualdub2 update 2 (build 40879)?
    This is the key question. If not, then I guess there's really no way to do this?

    Originally Posted by FLP437 View Post
    For sure now is the support to up to 8 LPCM or 8 DTS hdmi embedded channels .

    The statement from Magewell “Support for capturing of IEC60958/IEC61937 audio, including uncompressed audio such as 5.1 channel, 7.1 channel, DTS, THX, SRS and compressed audio such as AAC and MP3” is also not completely clear with regard to dolby.
    Is there any way to convert the Dolby Digital AC3 stream to 6 channel LPCM or would that change the "as is" nature of the Dolby digital? Or is it possible to somehow "inject" the unaltered Dolby digital stream into lossless video in real time?

    FLP437, any chance Magewell tech support could shed light on how to do this?
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  12. Originally Posted by end-user View Post
    Is there any way to convert the Dolby Digital AC3 stream to 6 channel LPCM...
    Once it's on the computer? Yes, BeSweet, among others, can do the job.
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    I will do in the weekend some tests to see if anything as changed if not I will try to contact magewell support about the issue.
    If the problem persist you can try black magic the intensity for instance it's also supported by virtualdub2.I don't know however if there are also any issue.
    However in general I do prefer the magewell is less triky and more stable and flexibe more feature rich pcie 2.0 vs 1.0 more advanced chipset adv 7842 vs adv 7180 faster and larger video buffer , etc.
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    Some DVD players and the like sometimes do have in the settings the option to output as lpcm I don't know if it's the case.
    Also if you do have a S/PDIF that can output as lpcm you can use some sort of hdmi embedder like this one
    https://www.amazon.com/gofanco-Prophecy-Extractor-Embedder-Toslink/dp/B07F6QXP7N/ref=m...r=8-1-fkmrnull
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  15. FLP437, I'd be interested to see what your testing shows. 2 years a go I looked at Blackmagic Intensity products and they could only record in 2 ch stereo, but virtualdub2 wasn't around then either.

    How would I be able to tell if the S/PDIF from my DirecTV DVR outputs LPCM or AC3?

    One worry I would have about using the Gofanco HDMI embedder in your link is that it uses HDCP 2.2. So if the HDMI signal coming out of my DirecTV DVR is HDCP 1.3 which then passes through an HDMI splitter/stripper which then passes through this HDCP 2.2 embedder, would the signal coming out of the embedder need the HDCP 2.2 stripped as well before it gets to my capture card?

    Another issue with the Gofanco HDMI embedder is that the very first Amazon reviewer (who is trying to embed 5.1 audio into HDMI) states, "So I’ve noticed an audio delay is introduced when embedding optical audio. It’s quite distracting, to the point where I can’t use this product."
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    It seems that somebody has already been able to capture ac3 dolby 5.1 hdmi embebbed using ffmpeg and a magewell card

    https://www.reddit.com/r/ffmpeg/comments/8wjxcx/hdmi_dolby_digital_capture_capabilities

    https://www.google.com/amp/s/amp.reddit.com/r/ffmpeg/comments/acuduf/hdmi_dolby_digita...lities_part_2/

    Based on my, FFmpeg example capture command line for two audio channels

    Code:
     
    FFmpeg -threads 8 -f dshow -video_size 1920x1080 -framerate 25 -vcodec v410 -rtbufsize 702000k -i video="Video (00 Pro Capture HDMI)":audio="Audio (00 Pro Capture HDMI)"  -acodec pcm_s16le -ar 48000 -ac 2 -vcodec ffv1 -level 3 -coder 1 -context 1 -g "1" -slices 24 -slicecrc 1 -y "E:\Test_FFV1.avi"
    and this information for linux perhaps some ffmpeg expert can make an optimized capture command line for this purpose for windows . I can try also but not sure I will get to it.

    Also if someone has already been sucessfull it's not a card problem . The weird thing is when I use a dolby digital hdmi source the card only identifies 2 audio channels and acts accordingly however if I put instead an lpcm or dts hdmi embedded audio source it identifies correctly the input and record the streams correctly.
    Last edited by FLP437; 25th Apr 2019 at 12:47.
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    Originally Posted by end-user View Post
    FLP437, I'd be interested to see what your testing shows. 2 years a go I looked at Blackmagic Intensity products and they could only record in 2 ch stereo, but virtualdub2 wasn't around then either.

    How would I be able to tell if the S/PDIF from my DirecTV DVR outputs LPCM or AC3?

    One worry I would have about using the Gofanco HDMI embedder in your link is that it uses HDCP 2.2. So if the HDMI signal coming out of my DirecTV DVR is HDCP 1.3 which then passes through an HDMI splitter/stripper which then passes through this HDCP 2.2 embedder, would the signal coming out of the embedder need the HDCP 2.2 stripped as well before it gets to my capture card?

    Another issue with the Gofanco HDMI embedder is that the very first Amazon reviewer (who is trying to embed 5.1 audio into HDMI) states, "So I’ve noticed an audio delay is introduced when embedding optical audio. It’s quite distracting, to the point where I can’t use this product."
    If you are using the 5.1 channel Dolby Digital output setting on your DVR, then it will provide Dolby Digital output. Also, even though an S/PDIF connection can provide 5.1 channel Dolby Digital audio or 5.1 channel DTS audio, it is limited to a maximum of 2-channel LPCM due to its bandwidth limitations.

    The Gofanco HDMI embedder should merely pass through whatever HDCP version is present in the signal it receives, and shouldn't add HDCP if there is none. If the Gofanco HDMI embedder added HDCP 2.2 to all outgoing signals then it would not work with anything other than newer UHD TVs and HDMI 2.0x receivers.

    It should be possible to correct audio delays during editing.
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  18. Originally Posted by FLP437 View Post
    It seems that somebody has already been able to capture ac3 dolby 5.1 hdmi embebbed using ffmpeg and a magewell card....and this information for linux perhaps some ffmpeg expert can make an optimized capture command line for this purpose for windows .
    I love Linux. Ironically, I chose Windows 10, because most of the capturing/editing software is in Windows or Mac. I wouldn't rule out some kind of double boot setup if you were able to confirm this works with the ffmpeg modification from your link on a Magewell card.

    Originally Posted by FLP437 View Post
    Also if someone has already been sucessfull it's not a card problem . The weird thing is when I use a dolby digital hdmi source the card only identifies 2 audio channels and acts accordingly however if I put instead an lpcm or dts hdmi embedded audio source it identifies correctly the input and record the streams correctly.
    I wonder if this phenomenon is somehow related to the problem I'm encountering playing DD from .ts and .mkv files in my other thread.

    Originally Posted by usually_quiet View Post
    Originally Posted by end-user View Post
    How would I be able to tell if the S/PDIF from my DirecTV DVR outputs LPCM or AC3?
    If you are using the 5.1 channel Dolby Digital output setting on your DVR, then it will provide Dolby Digital output. Also, even though an S/PDIF connection can provide 5.1 channel Dolby Digital audio or 5.1 channel DTS audio, it is limited to a maximum of 2-channel LPCM due to its bandwidth limitations.
    So I assume this limitation means that FLP437's suggestion of using the Gofanco HDMI embedder to add the 6 Dolby Digital channels to the lossless video won't work for my goal of creating a file of lossless video + DD 5.1?
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    Originally Posted by end-user View Post
    Originally Posted by usually_quiet View Post
    Originally Posted by end-user View Post
    How would I be able to tell if the S/PDIF from my DirecTV DVR outputs LPCM or AC3?
    If you are using the 5.1 channel Dolby Digital output setting on your DVR, then it will provide Dolby Digital output. Also, even though an S/PDIF connection can provide 5.1 channel Dolby Digital audio or 5.1 channel DTS audio, it is limited to a maximum of 2-channel LPCM due to its bandwidth limitations.
    So I assume this limitation means that FLP437's suggestion of using the Gofanco HDMI embedder to add the 6 Dolby Digital channels to the lossless video won't work for my goal of creating a file of lossless video + DD 5.1?
    If you are expecting the Gofanco HDMI Embedder to give you 6-channel LPCM output from DD 5.1 S/PDIF input, it won't do that. The Gofanco HDMI Embedder doesn't decode compressed digital audio signals, so it can't do that. The Gofanco HDMI Embedder can add DD 5.1 from an S/PDIF source to the HDMI video as DD 5.1.
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  20. Originally Posted by usually_quiet View Post
    If you are expecting the Gofanco HDMI Embedder to give you 6-channel LPCM output from DD 5.1 S/PDIF input, it won't do that. The Gofanco HDMI Embedder doesn't decode compressed digital audio signals, so it can't do that. The Gofanco HDMI Embedder can add DD 5.1 from an S/PDIF source to the HDMI video as DD 5.1.
    And that won't work with the Magewell card based on FLP437's personal experience. So then is there any way to convert the Dolby Digital AC3 stream to 6 channel LPCM before it gets to the Gofanco embedder or would that change the "as is" nature of the Dolby digital too much? And even if this is possible, wouldn't it potentially cause A-V sync issues?
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    Originally Posted by end-user View Post
    Originally Posted by usually_quiet View Post
    If you are expecting the Gofanco HDMI Embedder to give you 6-channel LPCM output from DD 5.1 S/PDIF input, it won't do that. The Gofanco HDMI Embedder doesn't decode compressed digital audio signals, so it can't do that. The Gofanco HDMI Embedder can add DD 5.1 from an S/PDIF source to the HDMI video as DD 5.1.
    And that won't work with the Magewell card based on FLP437's personal experience. So then is there any way to convert the Dolby Digital AC3 stream to 6 channel LPCM before it gets to the Gofanco embedder or would that change the "as is" nature of the Dolby digital too much? And even if this is possible, wouldn't it potentially cause A-V sync issues?
    There is no way to get six channels of LPCM to an HDMI embedder via an S/PDIF connection because S/PDIF can't carry 6 channels of LPCM audio.

    As I wrote in an earlier post in this thread, due to bandwidth limitations, S/PDIF cannot supply more than two channels of LPCM. LPCM is uncompressed digital audio. S/PDIF can only supply 5.1 channel audio if the audio is compressed using Dolby Digital or DTS.

    [Edit] FLP437 is going to experiment further with ffmpeg to see if he can get DD to work. You can also ask him if there are audio delays introduced by the Gofanco embedder.
    Last edited by usually_quiet; 27th Apr 2019 at 10:47.
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    Just a thought...

    Parties also may need to remember this is similar to the old AC3WAV or AC3onCD days: For an ac3 (or any compressed bitstream for that matter) to be used properly with SPDIF, padding bytes must be added in order for the throughput payload to match what is expected by the spec.

    Lacks of that may be what is hindering inclusion.
    And the presence of it will thwart decoding until the padding is removed first (or a decoder that is aware of this variant type is used).

    Scott
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    Originally Posted by Cornucopia View Post
    Just a thought...

    Parties also may need to remember this is similar to the old AC3WAV or AC3onCD days: For an ac3 (or any compressed bitstream for that matter) to be used properly with SPDIF, padding bytes must be added in order for the throughput payload to match what is expected by the spec.

    Lacks of that may be what is hindering inclusion.
    And the presence of it will thwart decoding until the padding is removed first (or a decoder that is aware of this variant type is used).

    Scott
    I found a thread at VideoHelp with a post which said that if DD is captured as 24-bit, bit-accurate 2-channel PCM, "BeSweet removes the padding, and renders a recognizable AC-3 file at whatever bitrate and channel content the original file contained."
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    @ end-user I don't know why I never thought about asking about this before but here goes: Did you ever try using kmttg to transfer those .tivo files to a PC? (Moved here from another of your current threads on a related subject)
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  25. After researching it for a few days, it appears that kmttg can only transfer .tivo files from standalone Tivo units, not from DirecTV Tivo THR22 or earlier like I have. And even on the standalone Tivo units, they don't allow transfer of certain "Copy proected" files, which ends up being about half the shows on the Tivo unit. It was a great thought though, usually_quiet!

    The Besweet solution sounds complicated but possible. Would there be no audio information lost in any of the six 5.1 channels in the conversion of AC3 to 6 ch LPCM by Besweet?

    I wonder if FLP437 has had time to test his Magewell card with the ffmpeg modification to see if the Magewell can capture 5.1 audio?
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    Originally Posted by end-user View Post
    After researching it for a few days, it appears that kmttg can only transfer .tivo files from standalone Tivo units, not from DirecTV Tivo THR22 or earlier like I have. And even on the standalone Tivo units, they don't allow transfer of certain "Copy proected" files, which ends up being about half the shows on the Tivo unit. It was a great thought though, usually_quiet!
    That's too bad. Unfortunately, I didn't know what TiVo features were incorporated into the DirecTV units and thought there was some possibility kmttg could work.

    Yes, kmttg only works for converting recordings which are marked "copy-freely". All recordings from local OTA broadcast sources should be marked copy-freely and I thought that the recordings that you wanted to save fit that description.



    Originally Posted by end-user View Post
    The Besweet solution sounds complicated but possible. Would there be no audio information lost in any of the six 5.1 channels in the conversion of AC3 to 6 ch LPCM by Besweet?
    I wasn't suggesting that you use Besweet to convert 5.1 channel AC3 to 6-channel LPCM. When AC3 is padded and formatted for transfer via S/PDIF it is often recorded as a WAV file by capture software. Some call this audio format "DDWAV". The post I referenced in my link was about undoing the DDWAV formatting and padding to re-create a proper AC3 with Besweet or Besplit . They are supposed to be able to undo the formatting. (Besplit command line: BeSplit -core( -input myfile.wav -prefix myfile -type ddwav -fix ) I don't know what the Besweet command line is. VLC is supposed to be able recognize and play DDWAV files, but turn volume way down just in case.
    Last edited by usually_quiet; 1st May 2019 at 09:48. Reason: grammar, clarity & fix link
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    Back in the day I remember there were few Windows XP programs that can extract recordings from DN and DTV PVR's hard drives. It has been a while now and finding them is not easy.
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    I made some additional tests

    Magewell card with latest driver / firmware and the more recent virtualdub2 build .

    Nothing has changed, It’s possible to capture LPCM and DTS HDMI embedded audio up to 8 channels in LPCM or AC3 (AC3 compression selected in virtualdub2 , if the source is up to 5.1).

    All DTS flavor’s up to 8 ch. seem s to work namely DTS-HD Master audio

    With Magewell capture express v 3.0 witch does only work with h.264 and AAC video / audio encoders ,I got similar results only Dolby versions don´t work (they work but I get stereo audio). Using Multiaudiocapture SDk utility I got same results.

    Audio file captured with the SDk utility has 24 bit depth as the original stream so I thought it could be bit-accurate 2-channel PCM, as so I tried to use besweet to decode and demux but didn't work either. I played around with ac3rec ,eac3to and besplit but no luck. However I don't know for sure if I have done it correctly, but I don't hear any noise from the captured file is a clear audio record so it seems more a decoded and down mixed stereo version then a compressed undecoded version

    I have put a sample capture from the SDk utility if anybody are willing to try to decode it and confirm it is a ddwav ( compressed AC3 wave file) or a standard stereo pcm file.

    As virtualdub2 can´t record 24 bit depth audio I also thought about shotcut and total record the only applications I know that can record video and 24 bit audio. But both app do have problems, shocut current releases crash with directshow capture devices namely magewell so I tried with an older version that did work but could not get a correct video capture. However if I do have more time I will explore a little more this path. I had also some problems with total record in the past so I have not tried it now.

    Related to the gofanko embedder as I don’t have one I can not test it and that wouldn't solve the problem either as already evidenced by usually_quiet.

    Didn´t try the Linux way as I don´t have a linux machine at hand and also because I didn't like the idea to take out and in multiple times a pcie card ( it´s not really a plug and play usb device) as I have a very stable capture station with the magewell and don’t want to change that.

    I was not able to mimic the Linux alsa pipe command for windows don't know if it can be done ,my knowledge is not enough so far .But I’m willing to test, if someone Is willing to make a similar command line for windows.

    There are 2 or 3 audio cards that are said to have a toslink input and able to record a faithful 24 bit audio file, but if they do work it will be necessary to capture with virtualdub2 simultaneous from different sources ( audio and video, not a big deal however), demux the audio afterwards, decompress with besweet or similar utility and remux again .However it seems these cards are very unique and difficult to identify for sure.

    I have contacted the magewell support about the situation and got the following answer

    "AC3 DDPlus and True HD are all encoded audio. According to IEC61937 standard, this kind audio is transferred by two channel. You just need to get the whole audio data and decode them to multi-channel LPCM audio."

    So the problem is how to get the whole audio data and after how to decode it
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  29. FLP437, bravo for doing all of that research. It is much appreciated! It helps us know what won't work. It sounds like the solution with the most promise is the Linux modification of ffmpeg + Magewell card.

    Originally Posted by FLP437 View Post
    The statement from Magewell “Support for capturing of IEC60958/IEC61937 audio, including uncompressed audio such as 5.1 channel, 7.1 channel, DTS, THX, SRS and compressed audio such as AAC and MP3” is also not completely clear with regard to dolby.
    Obviously after your inquiry with Magewell support, their statement above is misleading, because I think most people equate 5.1 audio with Dolby Digital.

    Thank you again for doing all of that extra testing.
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    Unfortunately so far the results have not been positive, there is a lot of information about this issue but not very reliable.
    I have tried also to interpose a splitter with edid control to try to force a 5.1 channels output but that didn't worked either.
    I have asked for additional information from Magewell but the guy I used to talk to as gone in paternity leave but he will return on 6th may perhaps he can give more practical and relevant information.
    the ffmpeg path in windows is still a possibility but I´m stuck to adapt the alsa linux command to windows
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