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  1. Please take look at the enclosed screenshot and suggest program, filters and levels to get the noise reduced and the colour/contrast and brightness as this is a very important video in the line of work i am in. It was recorded from vhs tape many years ago

    Thank you so much for advice and help on this
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    Last edited by perfection; 16th Sep 2011 at 12:51.
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  2. Member edDV's Avatar
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    Typical high black level washout.

    Also badly clipped whites. You can fix black but white detail is gone.

    Click image for larger version

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    Black -17.4 %
    White -7.2 %

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    Last edited by edDV; 16th Sep 2011 at 12:58.
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  3. Member hech54's Avatar
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    Never shoot towards a window.
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    As edDV has said, the black/white levels are wrong - leading to a faded image.

    Additionally, it looks like the video was shot with a 'soft focus' lens filter; for example a Tiffen Promist or similar. There's also visible chroma noise and colour banding.

    Soft focus filters are often overused, even on high end TV and film productions. Used subtly, they can enhance the image and make it seem less 'every day', but used excessively they make the image bleary and IMO cause eye strain.

    Also, lighter parts of the image will spread over dark areas. That's a likely cause of the raised black levels - under the lady's arm, and the black beam in the background.

    The soft focus effect can be partially reversed by using one or more unsharp mask filters. But care needs to be taken when using them - setting the filter strength too high will cause unnatural edge artefacts and halos.

    There's two important controls for an unsharp mask filter:
    Amount - The overall strength of the filter
    Radius - The width of the unsharp mask effect

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    In the example above, 3 unsharp mask filters were used; one with a radius of 180px, another with a radius of 80px, and also one of 40px. The amount/strength of each filter was adjusted by eye to reduce the mist, but not introduce obvious halos.

    Also a bit of noise reduction, a standard sharpen filter to add a bit of definition and some colour correction.

    GIMP and Blender were used to process the image you posted. Neither programs are likely to fit well into your work flow, but I used them as proof of concept for the processing.

    edDV can probably suggest some commercial programs that have unsharp filters that can be 'chained' together as I don't have much knowledge in this area. Maybe After Effects, or similar.

    Also, the order in which the filters are applied is important. An unsharp mask can increase contrast and possibly lead to clipped highlights if applied after levels correction. Start with the unsharp mask filters, then correct the levels and finally apply noise reduction and a standard sharpen.

    note: I couldn't apply decent noise reduction on the still image you posted, as better video noise reduction filters work temporally as well as spatially and require moving video to work.
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  5. Member budwzr's Avatar
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    After reviewing the material posted, I have reached the following professional evaluation and report:

    It's HOSED!
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  6. Member edDV's Avatar
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    I think there is enough there to make it presentable.
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  7. You need a chroma smoother like "Camcorder Nose Reduction" in Virtual Dub. Or Neat Video may be able to get rid of most of the chroma noise. A masking filter like the secondary color corrector in Sony Vegas would help you select and desaturate/reduce gamma in the window area. Vegas also has a respectable sharpner. Levels need to be adjusted, obviously. There is also a script/function called fixchromableeding() for AVIsynth that could mask some of that halo/chroma bleed.

    I agree, it looks like a soft filter was used because nothing in the shot is in focus.

    Denoise, chroma denoise, chroma smooth, mask for gain, levels, sharpner, white balance. Using a combo of those things should get the footage looking good. Denoisers, chroma and the like can be done in AVISynth and Virtualdub. Color corrections, masking and sharpening is best left for a good NLE like Vegas.

    Avoid median filters, as the image is already "blurry".
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