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  1. Lossless x265 is extremely slow, not really suitable for capturing. It can achieve a very good compression ratio but that comes at a cost.

    Capturing lossless 720p (I presume 50 or 60fps?) is going to be bandwidth heavy in general, so it you would need a fast hard drive for it. Most scalers, at least cheap ones don't support 480i/586i output though. For that you would need a DVD-recorder with HDMI out ( + HDMI splitter to avoid HDCP), or a more fancy professional video processor or similar.

    I don't think the Sony has a TBC (Adaptive picture control is not a TBC), and even if it did, consumer VCRs don't have the TBC active on the input signals, only on the video coming from the VCR itself.
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    So, the workflow I previously mentioned seems to be working as things look and sound really good at 720p. However, the downside is is that I can only perform a successful capture from Virtualdub2 x64 (Surfacebook, Windows 10 1903, 8 GB RAM, 256 GB SSD) when my video compression is set to uncompressed (audio is set to 48000 kHz 16-bit LPCM).

    When I choose FFMPEG x265 lossless, the playback in the default Movies app speeds through the video and the audio plays fine and then will go to chipmunks/smurfs after 30 seconds or so. Same thing happens when I capture directly to compressed x264 aac/mp4. In addition, any other lossless codec I use that comes with Virtualdub2 (FFMPEG FFV1 lossless or FFMPEG Huffyuv lossless or Lagarith lossless) looks like it captures, but when played back in the Movies app gives an error that the playback can not be performed because the codec is not supported, but you do hear the audio, and it too sounds like chipmunks/smurfs after 30 seconds or so despite no video because of the lack of codec support. So, needless to say, I think my issues are software related to Virtualdub2 and more specifically with the video compression.

    To confirm this, I did a quick capture in Magewell’s Capture Express that captures directly to compressed x264 aac/mp4 (just like I did in Virtualdub2) which actually played back just fine both video and audio, albeit this software did not preserve the 4:3 aspect ratio. Regardless, it showed me something is amiss with the Virtualdub2 software video compression piece.

    Any suggestions on how to get alternate lossless compression codecs into Virtualdub2? Or am I better off using original Virtualdub 1.10 or even 1.9 as I’ve seen some suggest?
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  3. Originally Posted by tmarzetta View Post
    So, the workflow I previously mentioned seems to be working as things look and sound really good at 720p. However, the downside is is that I can only perform a successful capture from Virtualdub2 x64 (Surfacebook, Windows 10 1903, 8 GB RAM, 256 GB SSD) when my video compression is set to uncompressed (audio is set to 48000 kHz 16-bit LPCM).
    First of all, video capture is a realtime process. A new frame of video arrives from the capture device every 1/30 second (or 1/25 second for PAL sources). If the computer is busy compressing the last frame (or just doing something else) the next frame will be lost. So the whole idea is to burden the computer as little as possible while capturing. Then once you've finished capturing the video, go back and use whatever codecs you want to create your final compressed product.

    High compression video codecs like x264 or x265 are too slow for video capture unless you use very fast settings. But if you do so they have very little advantage over a fast lossless codec like huffyuv. Audio codecs like Lame MP3 or AAC are also too slow.

    Windows has two systems for dealing the video capture and playback: VFW and DirectShow. The two systems are separate and not compatible with each other. Codecs installed for VFW are not available to DirectShow programs, and vice versa. In additions, programs can use their built-in codecs rather than (or in addition to) VFW or DirectShow. Many video capture programs use VFW (VirtualDub, for example). Most media players use DirectShow. If you want to play your captured video in a media player you need to use a video codec that's available in both environments -- or a player that has a built-in decoder for the codec. In addition to this, when running 64 bit windows, you have both 32 bit and 64 bit subsystems. 32 bit programs cannot see 64 bit codecs. 64 bit programs cannot see 32 bit codecs. So with 64 bit Windows you have four separate video systems.

    Uncompressed SD video capture requires too much hard drive bandwidth (about 75 MB/min) for older hard drives. Large modern drives may have sufficient bandwidth at the faster outer cylinders, maybe even at the slower inner cylinders, but if Windows decides to read/write some system files while you're capturing (and it does this all the time, especially Win10) you'll end up dropping frames.

    Don't browse the internet, watch youtube videos, play games, or run any other programs while capturing. Turn off your antivirus. Turn off Windows file indexing.

    So use a fast video codec (huffyuv) and no audio compression while capturing. Expect big files -- 30 to 40 GB/hr with standard definition caps. If you must use a player that doesn't directly support huffyuv -- ffdshow supports it for decoding for both VFW and DirectShow and both 32 bit an 64 bit.

    In addition to all that, VirtualDub has some quirks with its video capture. Do not play the audio while capturing: turn off Audio -> Enable Audio Playback. On the Capture -> Timing... dialog you may have to play around with the Resync Mode settings. Start with Do Not Resync...

    Originally Posted by tmarzetta View Post
    When I choose FFMPEG x265 lossless, the playback in the default Movies app speeds through the video and the audio plays fine and then will go to chipmunks/smurfs after 30 seconds or so. Same thing happens when I capture directly to compressed x264 aac/mp4.
    The settings you used were too slow. You were dropping frames and VirtualDub tried to re-sync causing problems. If you really want to capture with one of those codecs use the ultrafast preset, no b-frames, all i-frames (or very short GOPs). If you don't know what that means forget about using those codecs.

    Originally Posted by tmarzetta View Post
    In addition, any other lossless codec I use that comes with Virtualdub2 (FFMPEG FFV1 lossless or FFMPEG Huffyuv lossless or Lagarith lossless) looks like it captures, but when played back in the Movies app gives an error that the playback can not be performed because the codec is not supported
    FFV1 is too slow. Lagarith is borderline (ok on fast computers, not on slow computers). Use huffyuv. Install ffdshow for decoding in players that don't support it.
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