if I have a 1920x1080 video track and want to crop the excess - how can I get the track resolution without the excess information on the render?
For example, after crop the source track 1920x1080 - I should get an image with dimensions of 400x800 pixels. How can I make the render be exactly with this resolution?
in other words
how to apply crop in such a way that the resolution on the renderer is reduced?
Are there different ways to achieve the goal?
Hi, and welcome to the forum and community.
The project settings define the standard output resolution of the video. Therefore, if you want your final video to be 400x800, set your project profile to that resolution. Then, when using source clips with 1920x1080, you will have black bars above/below or left/right, because Kdenlive tries to fit it into the project’s dimensions. Therefore, you need to use a Transform effect to zoom into the clip to fill the screen.
Alternatively, you can use the Rescale option in the render dialog window to go from 1920x1080 project dimension to 400x800. Keep in mind this will distort the video as 1920x1080 and 400x800 have different aspect ratios.
if we don’t know in advance - what should be the output resolution?
I adjust the required rectangle size using crop-type effects. And after cropping, I want all unnecessary information to be removed. It was 1920x1080. And it became as I cropped using crop. I don’t know what resolution exactly is there. We just crop to the required size and don’t know in advance what resolution is required.
Same question: reddit - com/r/kdenlive/comments/e24y92/how_can_i_crop_the_entire_project_ie_output/
look at the example of a “typical” crop (Bandicam), where it is not the image that is necessarily cropped. Not just the image. But the image resolution cropping.
Overlaying a screen in the form of black bars does not make sense. A real crop is needed, discarding unnecessary bits of information. Not a sketch in black over
Well, unfortunately, Kdenlive (and I mean the software, not you) doesn’t work that way. If you do not know the resolution of the output video before you start your project you are out of luck. Usually ppl know what their target audience and use case are for the video they are producing.
There is a possible workaround, though. I haven’t tested that but I think it can work. Assuming you have a video clip 1920x1080. Use the Crop, Scale and Tilt effect to crop the clip as desired. You are doing this by specifying the number of pixels to be cropped on all four sides. Then do the math: 1920 - left_crop - right_crop = new_width; 1080 - top_crop - bottom_crop = new_height. Now create a new project profile with the dimension of new_width x new_height and the correct aspect ratio (you can enter the new_height and new_width values), and change the current project profile to the new one. Keep in mind that changing project profiles in mid-editing is not recommended, in particular when using keyframes.
for example, I wanted to crop the video resolution to create stickers for the telegram social network. And how can I know the resolution in advance if the purpose of cropping is by content. And not by some other criterion?
great. But what if you suddenly want to change the crop ratio? Repeat the whole procedure again? 
