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  1. Hi,

    i want to insert an image into the video that overlays the full screen for a few seconds, and save the video as stream copy so there is no quality loss. I tried virtualdub and Donald Graft logo which is simple to use and does the job. However i noticed there is some quality loss with smart render and ffdshow as codec. Is there any alternative out there for this?

    Thank you.
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  2. The part with the logo must be re-rendered. If that section is significantly lower quality with VirtulDub's smart renderinb set ffdshow to higher quality settings.
    Last edited by jagabo; 21st May 2012 at 08:26.
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  3. That part is fine even if its not rendered at full quality since it lasts barely 5 seconds, but i just feel the rest of the video loses quality too. In fact, the video frame rate is over 9500Kbps before applying the smart render but it decreases below 7300 after that despite ffdshow is set to its maximum bitrate (10000). Maybe i need to adjust some other settings too?

    Thanks.
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  4. Member
    Join Date: Jul 2001
    Location: United States
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    To eliminate any re-encoding I'd:

    - Split the video into three parts
    - Beginning of video
    - The 5 sec clip you want to overlay
    - End of video

    - Re-encode the new segment with your overlay using the SAME resolution and bitrate as the original video.

    - Merge the three segments back together.
    Have a good one,

    neomaine

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  5. You mean the part before the inserted image, the part with the inserted image and the part after it? i had that idea too but i wonder if there is a more practical way.
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  6. Originally Posted by supercain View Post
    That part is fine even if its not rendered at full quality since it lasts barely 5 seconds, but i just feel the rest of the video loses quality too. In fact, the video frame rate is over 9500Kbps before applying the smart render but it decreases below 7300 after that despite ffdshow is set to its maximum bitrate (10000). Maybe i need to adjust some other settings too?
    I think VirtualDub doesn't realize that the logo filter only change a short range of frames. Try using the Curve Editor to indicate which parts of the video have changed and which haven't.

    Nevermind. Donald Graft's logo filter doesn't seem to work with the curve editor.
    Last edited by jagabo; 21st May 2012 at 09:04.
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  7. I selected curve editor from the menu but nothing happens. Only what appears to be a scroll bar and a message that says there are no video filters with parameter curves. Maybe the logo filter doesnt allow it?
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  8. Ah, I forgot, you need to enable the Blend option for the logo filter on the main filters dialog. Then it will show up in the Curve Editor.
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  9. I did it and now i get the editor but after selecting blend now the logo image doesnt show. Am i doing something wrong?
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  10. VirtualDub doesn't know the Logo filter only applies itself to some frames. You have to use the Curve Editor to tell it only to apply the filter to a range of frames:

    Click image for larger version

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    In this sample the filter is being enabled from frames 400 to 450. VirtualDub completely removes the filter for the rest of the video. If you don't draw a graph the filter is applied zero percent (ie, not applied) to the entire video.
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  11. Thank you. But on a second thought maybe its easier if i put the image along with the subtitles so everything is encoded at once. However i cant get the subtitles to show above the logo and they get covered by the logo instead. Is there any way to change the layer order of the filters?

    Thank you.
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  12. VirtualDub applies filters in the order they appear in the filters dialog. So put the Logo filter above the TextSub filter.
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  13. Thats what i thought first but it was not working. Now i understand. For some reason the filter that goes up in the filters dialog goes down on the video. Weird but the important thing is that now it works.

    Thank you again!
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