Trouble with cropping

[martiinvie]

Hi everybody,

 

Please check out the screenshots here.

 

I had a video with aspect ratio 4:3 (960x720). I edited in VideoPad3.00 (screenshot 1)

 

and exported it again with aspect ratio 4:3 (640x480). Result: screenshot 2.

 

I was not happy with the grey squares that showed at the top of the picture, so I thought I would crop it. See screenshot 3.

 

Again I exported the video 640x480. But the result was as seen in screenshot 4.

 

Only when I exported with an aspect ratio of 16:9 (1024x576) I got a result as in screenshot 5, but with lots of black space left and right.

 

What went wrong and how can I get a correctly cropped picture when exporting to 640x480?

 

I am using VideoPad 3.00 for Windows.

 

Thanks

 

Martin

[Nationalsolo]

Hi

Placing at 960 x 720 image on the timeline will produce the result of screenshot 1

Outputting this as a 640 x 480 video should look exactly the same. There should not be any chequered bar at the top. I can't see where these may have come from as even if you crop to different sizes the OUTPUT should always show the chequered area (visible in the clip preview pane) as BLACK.

 

However....I think there is a bug in the CROP effect. (Version 3.6)

 

As a Test....Put a 960 x 720 image (AR 4:3) on the sequence line. In the preview pane it is shown fully with black areas to each side. So far so good.

Let's say you want to crop just a little of each side but keep the AR 4:3 (or indeed, just want to trim each side a little)...In the crop effect drag the sides of the rectangle in to just remove the unwanted bit..or force 4:3 and do the same. The sequence preview shows a correct result. So far apparently OK.

 

Now output the sequence as a 640 x 480 avi. (4:3) You now see that the image in the sequence has been incorrectly cropped. The degree of cropping with the rectangle (which has to include the black borders) has ALL been taken from the image, which is incorrect. The output should look like the treated clip preview pane.

Zoom to crop area makes no difference either.

 

Anybody want to confirm this?

 

Can NCH comment please?

 

The fundamental problem here is that the X1% and X2% crop values start from the edges of the 16:9 screen and not the 4:3 image edge. Moving the edge of the rectangle to the edge of the 4:3 image should theoretically give 0% and 100% not 12% and 88%. It is this amount that is taken from the image.

I get the feeling that the crop effect window should show the just the IMAGE whatever its ratio and not the complete 16:9 area. How can one crop just the edge of a 4:3 image if the rectangle cant be positioned correctly?

 

Nat

[Nationalsolo]

Hi

Played with this a bit.... It's not that intuative...but...

What you need to do is to crop your image to 4:3 and adjust until the bit you don't want is cropped off.

Click the "Zoom to cropped Region" box, and Apply.

 

Now..If you save your video as a 4:3 AR as you have been doing, you will find your image incorrectly cropped as discussed above.

 

You must save your video as a 16:9 ratio output. e.g. 720 or 1080...

Your image will now be 4:3 AR in keeping with the original but in a 16:9 black frame.

For a test try placing a 4:3 image on the timeline and then splitting it into two sections.

Apply the crop and trim to the first section as described above and then output the whole sequence as a 720 video.

Both sections will (should) remain the same size and be 4:3 AR in keeping with the original image..

 

Nat