[Kdenlive-devel] how do i crop video?

[Dan Dennedy]

On Thu, Aug 13, 2009 at 7:21 PM, sean darcy<seandarcy2 at gmail.com> wrote:
> Dan Dennedy wrote:
>> On Wed, Aug 12, 2009 at 7:54 PM, sean darcy<seandarcy2 at gmail.com> wrote:
>>> With today's kdenlive svn and mlt git, I'm trying to put a 1990 school
>>> play on dvd. I've copied it from vhs on a svhs deck to a camcorder, then
>>> used dvgrab into the pc.
>>>
>>> The video has some noise around the edges. I'd like to crop it, and
>>> insert black borders to fit ntsc size before conversion to mpeg.
>>>
>>> How do I do this in kdenlive? I can't find any "crop" tool.
>>
>> There is a crop in the video effects list. It was added in version
>> 0.7.3. It is not dependent upon any libs/plugins external to MLT, so I
>> am surprised you do not see it as I know you run a very up-to-date
>> system. If you run 'melt -query filters 2>&1 | grep crop' do you see
>> it? If so, do you see a $prefix/share/apps/kdenlive/effects/crop.xml?
>>
> OK, I'm blind, but now I see.
>
> Now that I've found it, is there any way of seeing the effect? That is,
> from the monitor I can see about 10-14 pixels of noise on the bottom and
> left side. As I adjust the crop parameters, I don't see any change in
> the monitor. Should I? If not, it's realllly hard to guess the actual
> crop needed.

It should show as you adjust. If you think there is some repaint
problem, then scrub a little. Also, there is a known bug that it does
not work in conjunction when you have changed the clip speed.

> Once I do crop, is there some clever way of adding symmetrical black
> borders to bring the clip back to 720x480?

This is automatic. Do you see how MLT automatically scales and pads to
fit the image attributes of the project setting (MLT profile)? When
you crop, you remove rows or columns from the source image before
these things take place.

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+-DRD-+