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  1. I am trying to capture from a Sony mini-DV DCR-TRV30 camcorder. I bought an IEEE1394 PCI-e card, installed it in my desktop and connected it to the camcorder.
    Using WinDV to capture while playing back miniDV.

    I see that the video is playing smoothly on the camcorder screen and also in WinDV. But when I playback the captured avi file I see intermittent flicker. It is pretty annoying. I used scenalyzer and am seeing same flicker during avi playback. I stuck to default settings for both WinDV & Scenalyzer.

    I converted the avi file into mp4 and surprisingly I don't see the flicker while playing back mp4. However I do see the resolution is not the best when there is movement in the video (like a hand wave); I can see some kind of "pixeling" around the movement. Pardon me if I am not explaining this part properly.

    Will appreciate any inputs on:
    * Why I see flickering when captured avi file is played back. What can I do to eliminate this?
    * How I can get best resolution captured from the DV tape. Any settings I specific setting I should use during capture and conversion to mp4?
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  2. When you "capture" with WinDV and a firewire card you are losslessly transferring compressed video directly from the camcorder to a file. The video and audio data in the AVI file are exactly the same as the video and audio on the tape.

    Flickering on playback may be because your player is using a single rate deinterlacer. 25p or 30p video is pretty flickery with high contrast material in motion. Try changing the player to double frame rate deinterlaing. Or using a different player.

    It sounds like you are seeing interlace comb artifacts in your converted file. And maybe using too little bitrate. You don't say what software and settings you are using for the conversion but make sure it's set to double frame rate deinterlacing (25i to 50p, or 30i to 60p). And make sure it understands your video is interlaced, bottom-field-first. How much bitrate you need depends on the codec (mp4 is a container, it can contain video and audio compressed with a variety of codecs) and the content (more action/motion requires more bitrate).

    You should post some short sample videos of the captured AVI and converted MP4.
    Last edited by jagabo; 1st Dec 2021 at 08:59.
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  3. But when I playback the captured avi file I see intermittent flicker. It is pretty annoying.
    Wrong field rate probably

    I converted the avi file into mp4 and surprisingly I don't see the flicker while playing back mp4. However I do see the resolution is not the best when there is movement in the video
    Basic single rate interpolator byproduct.
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  4. Originally Posted by jagabo View Post
    When you "capture" with WinDV and a firewire card you are losslessly transferring compressed video directly from the camcorder to a file. The video and audio data in the AVI file are exactly the same as the video and audio on the tape.

    Flickering on playback may be because your player is using a single rate deinterlacer. 25p or 30p video is pretty flickery with high contrast material in motion. Try changing the player to double frame rate deinterlaing. Or using a different player.

    It sounds like you are seeing interlace comb artifacts in your converted file. And maybe using too little bitrate. You don't say what software and settings you are using for the conversion but make sure it's set to double frame rate deinterlacing (25i to 50p, or 30i to 60p). And make sure it understands your video is interlaced, bottom-field-first. How much bitrate you need depends on the codec (mp4 is a container, it can contain video and audio compressed with a variety of codecs) and the content (more action/motion requires more bitrate).

    You should post some short sample videos of the captured AVI and converted MP4.

    I am using Windows Media Player to play the avi clip on my PC. I don't see how to change these settings for it. Is there a specific player you would recommend? And how/where to change the frame rate de-interlacing?

    I used cloudconvert.com to convert avi to mp4. I don't know which fields I should change to select the options you specified above. Let me know if you recommend a specific converter and settings I should use with it.

    I tried with a different miniDV tape and this one doesn't show the flicker! Same setup as before, scenalyzer to capture and Windows media Player to play back the avi file. What's strange is that the tape that shows flicker plays without any flicker on the camcorder, the reason I created this thread.
    Last edited by rvvideo; 2nd Dec 2021 at 01:45.
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  5. Originally Posted by s-mp View Post
    But when I playback the captured avi file I see intermittent flicker. It is pretty annoying.
    Wrong field rate probably

    I converted the avi file into mp4 and surprisingly I don't see the flicker while playing back mp4. However I do see the resolution is not the best when there is movement in the video
    Basic single rate interpolator byproduct.
    Where do I specify the field rate during capture? During playback of the avi file?
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  6. Try putting the file into virtualdub2
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  7. As a test open the file with VirtualDub2. Select Video -> Filters... Press the Add... button. Double click on the Bob Doubler filter. Make sure Bottom Field First and Bob are selected. Press OK to add the bob filter. Press OK to close the Add Filters dialog. At the main VirtualDub window use the left and right arrow keys to single step through the video. In the output pane you should see some up/down bouncing/flickering of horizontal edges (hence the name of the deinterlacing method) but other than that there should be no flickering. And when there's motion you should see it in every frame. In the input pane you should see combing and motion at every other frame.
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  8. Thank you for the suggestions. I downloaded VirtualDub2, opened one of the avi files I saved with scenalyzer, use the "Bob Doubler" settings. I do see that the video is slightly better but the output file size grew by 20 times (input was 200KB, output was 3.5GB!). Is this expected?
    BTW were you suggesting that I should capture from camcorder with VirtualDub2?

    I am kind of confused on how to proceed. What should I use to capture from my camcorder? Virtualdub2 or scenalyzer? What settings should I use, above settings during capture?

    And what to use to convert to mp4?

    I have 40+ miniDVs and want to give this a solid try.
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  9. You don't need to save the video. Just look at the output pane in VirtualDub2. When you step through the video frame by frame with the arrow keys do the frames vary in brightness? During panning shots is the motion smooth in the output pane? Motion with every frame, not motion every other frame.
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  10. Yes the motion is smooth in the output pane with Bob doubler every frame. I used the arrow keys to step forward and backward.
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  11. And the output pane is free of comb artifacts?
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  12. Yes it is. Much much better.
    What does all of this mean ? That I can use WinDV/Scenalyzer to capture as is from camcorder?
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  13. It means that the firewire capture is fine. What you are seeing in VirtualDub2 is exactly what one expects to see. The problem is in your playback and/or conversion. Upload a short sample of the DV cap that clearly shows the flickering you see at playback, and that same sample converted as you have been doing. That will help determine what's going wrong.
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  14. Will do.
    What SW would you suggest to convert avi to mp4? And what settings to use?
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  15. You can use VirtualDub2 to create a DV sample. Open the video. Select Video -> Direct Stream Copy. Mark in and mark out to select a section, then File -> Save Video... Make sure Save as type is set to AVI. Name the file and save.

    Use that file to create an mp4 video with whatever software you were using before.

    Upload the AVI and the mp4 created from it.

    You can also use VirtualDub to create deinterlaced mp4 files:

    1) Open your DV AVI file in VirtualDub2.
    2) Select Video -> Filters.
    3) Add the Deinterlace filter. Set Deinterlacing mode to Interpolate Ysing Yadif Algorithm. Set Field Order to Double Frame Rate, Bottom Field First.
    4) At the main VirtualDub2 window select Video -> Compresssion... Select a video codec -- for now try x264 8 bit and accept the default settings.
    5) Select Audio -> Full Processing Mode, then Audio -> Compression... Select FFMpeg AAC and the default settings.
    6) Select File -> Save Video... Set Save As Type to MP4 =faststart. Set the name and folder. Press the Save button.

    A small dialog will pop up showing the progress. When it's done your mp4 file is ready. It may not be the best quality because we used the default compression settings but the deinterlacing should be good. The playback should be smooth with no flickering.
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  16. Thank you very much for the detailed instructions. I really appreciate all your help here!
    Here are all the sample input and output files. Filenames are self-explanatory too.

    Input avi sample = T1_inp_avi_sample.avi
    Cloudconvert options = avi2mp4_cloudconvert_options
    Cloudconverted mp4 = T1_inp_sample_couldconvert_to_mp4.mp4
    VirtualDub2 converted mp4 = T1_inp_asmpe_virtualdub2_to_mp4.mp4

    To see flicker of input avi = open it with Windows Media Player or "Movies & TV" app on Windows PC.

    Hope this will help shed more light.
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  17. It looks like there are errors in the DV stream. The errors are causing Windows Media Player to play the video incorrectly towards the end of the clip -- with the frame size flickering back and forth between 16:9 and 4:3.

    Image
    [Attachment 62187 - Click to enlarge]


    Image
    [Attachment 62188 - Click to enlarge]


    I'm guessing this is the flickering you are talking about. Other players I tried did not show that flickering -- they just played the video as 16:9:

    Image
    [Attachment 62189 - Click to enlarge]


    There were some visible decoding errors in the other players though. Note the displaced blocks at the right of the frame, near the girls head:

    Image
    [Attachment 62190 - Click to enlarge]


    The errors could be caused by the firewire transfer from camcorder to the computer (though I think this unlikely), the reading of the tape, or they could be on the tape itself. Try cleaning the tape heads. If you get exactly the same errors every time you capture that sequence the errors are on the tape (not unusual for DV). If you have access to another DV camcorder you could try using that.

    The cloud converted video wasn't deinterlaced and it was encoded progressive. That's obviously wrong but otherwise it doesn't show the flickering, just the decoding errors. The VirtualDub2 encoded video is properly deinterlaced for display and plays smoothly. It show the small decoding errors but no flickering.
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  18. I will try to clean the heads, recapture and see how it goes (I need to find a cleaner).

    With respect to the whole procedure, could you suggest how I should proceed with my full library of tapes? This is what I gathered so far:
    1. Capture using WinDV or Scenalyzer. Default settings. I would like to keep each tape to a couple of avi files. Per scene avi will be too many files for me. I plan to keep each tape as a separate folder and put all files in there.
    2. Open each file in VirtualDub2, use the settings you provided above to create de-interlaced mp4. Each avi gets saved as a single mp4

    Is there a way to let VirtualDub2 run in "batch mode" without having to open each file, convert to mp4, save mp4? I am ok if I can run it per tape/folder.

    Thank you for all the detailed instructions.
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  19. Regarding number 2, the default settings for the x264 encoder may not be suitable, depending on what you plan to do with the files. First the aspect ratio is wrong. You should set SAR Width to 32, SAR height to 27. You may want higher quality than Rate Factor 23 (lower values give higher quality). I usually use 18 for SD video I plan to watch. I usually set the Preset to Slow. Other settings may need changing too. You may want to increase the quality of the audio compression too (higher bitrate than the default 128 kbps).

    For better deinterlacing you'll need to use AviSynth or VapourSynth -- and the QTGMC filter (sample attached). But those have steep learning curves.

    For batch encoding you can use ffmpeg. A basic batch file would be something like:

    Code:
    for %%F in (*.avi) do ( ffmpeg -i "%%~nxF" -vf yadif=1 -c:v libx264 -preset slow -crf 18 -acodec aac "%%~nxF.yadif.mp4" )
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  20. Hi,
    I finally got to play with the settings including the non-default values over the holidays.
    My goal is to be able to watch these compressed videos on the laptop, tv and even on the phones thru a media server (I got a simple one).

    My video looks ok w. the non-default settings you suggested.
    Would you suggest something else other than the x264 encoder that comes with VirtualDub?

    I have an additional question. Is there any way to get the date/time stamp (meta data) to be overlayed (like a watermark) on the converted video in VirtualDub? I am aware of some commercial video editing sw like Cyberlink PowerDirector that allow you to do that.
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  21. Capturing Memories dellsam34's Avatar
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    No one want a date and time printed permanently on the video, That's so 90'ish. You can check the metadata with whatever player you are using to display the date, usualy it's the info button, I'm pretty sure Jagabo has a way of setting that up during encoding.
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  22. Call me old fashioned. I do like to know when that video was taken while watching especially if it was more than 10 years ago.
    None of the players I am using (including on phone) have options to display the meta data while playing encoded video. Atleast I couldn't find it.
    My camcorder has the "Display" button to show this meta data. But that is only when I am playing the tape on it.
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  23. I don't know how to get the DV creation date metadata. The ffmpeg commands I know only show the file creation date. Drag/drop batch files:

    Code:
    ffmpeg -i %1 -f ffmetadata "%~dpnx1.metadata.txt"
    Code:
    ffmpeg -i %1 -c copy -map_metadata 0 -map_metadata:s:v 0:s:v -map_metadata:s:a 0:s:a -f ffmetadata "%~dpnx1.metadata.txt"
    One thing to consider is to make soft subs with the timestamps. Then you can easily turn them off/on in most players.
    Last edited by jagabo; 5th Jan 2022 at 23:30.
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