[Kdenlive-devel] how do i crop video?

[sean darcy]

Dan Dennedy wrote:
> 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.
> 

OK, I can see it if use the Project Monitor. I'd been using the Clip 
Monitor. BTW, look at how avidemux shows a crop. It allows you to zoom, 
and uses green to show the crop. At least for me, a little easier.

But now I can't get it (svn 3822) to render. The Render rondel, 
ctl-enter, all bring up the Rendering dialog. I can choose all sorts of 
output. I chose ntsc, mpg 8000k, 2 pass. Then nothing. There's a Close 
button, but that just closes the dialog. Where's the Render Now button?

sean