Zoom effect and image defintion

gaab

Hello,

I have a large panorama picture I want to show full height by moving the "view frame".

I was instructed to use the Zoom effect which achieves what I want to get, BUT the result is so blurry that I cannot keep it.
Apparently the definition of the picture is reduced at load time to adjust to the width of the frame.

How to force VideoPad to use the original file BEFORE reduction of the picture definition ?

borate

Is the poor preview resolution the same as that of the exported video file?

gaab

Unfortunatly, YES...

A "slice" of the panorama (using Irfanview) : the pano is 2695*2804 pixels..

A print screen of the video rendering (using VLC)

Parameters to create the video :

mp4, 1920x1080 - Youtube 1080p - Frame rate 24

MP4 Encoding setup : H264, quality 20

The "normal" other picture are as good looking as the original pictures...

Thanks for any suggestion

(Video Pad version 4.21

borate

What is the resolution of the original image? If low, then zooming may degrade it significantly.

gaab

Sorry, my update of the message has "crossed" your question.

As you can see, the definition is very high 2804 pixels height

[deleted]

Tried this out with a large image 4480 x 2520 and cropped this to 2695 (W) x 2804 (H) to match your starting panorama. This is the original after cropping.. (jpg)

This image was placed in the timeline and zoomed (16:9) with keyframes to produce a pan across the frame in 10 seconds.

This is the VP screen viewed in preview set at 1920 x 1080. This still looks pretty sharp to me.

Here's an VLC output image from the video

Parameters to create the video :

mp4, 1920x1080 - Youtube 1080p

MP4 Encoding setup : H264, quality 10 This is the only setting differing from yours. You set yours at 20

This, IMHO is not a bad result. The video pans from side to side of the full frame in 10 seconds.

A VLC screen copy of a video exported at a quality setting of 20 shows very little difference.....

So little in fact that they have to be placed side by side to see the difference....

I can't see why your VLC output is so much worse than your original image.

Nat

[deleted]

Looking closely at your panorama image, I note it is actually 26895 x 2520 and not as you quote 2695 x 2520. Any way, I copied your image to repeat the above tests.... Even as a 2560 x 1440 jpg as used here (and obviously reduced on your upload image site) it didn't come out as bad yours seems to have done.....

Below.......The Image (256 x 1440) placed on the timeline and the Zoom effect applied to start on left and finish on the right (16:9 format restraint)... Pan time for frame to travel from side to side = default duration of still images (10 seconds)...

The exported mpeg4 played OK and looked OK. I used the same settings as you quote in your post. As in my previous post (above) here is a composite of the original image (left) with a screencopy of video played on VLC exported as an mpeg4 at quality 10 (centre) and the same at quality 20 (right)

Taking into account that the original used here was a reduced version of the one you used and the above composite image is a jpg, further reduced to fit the forum page I can't see a great deal of difference between them......I still can't see why yours is so much worse.

Nat

gaab

Sorry for the typo 🙁 (bad copy/paste !), specially as the origin of the problem, according to me, is this more than 5 time width compared to the standard 16/9 format !

I did made a test with a decrease definition to 10359x1080 with no improvement.

Due to the width of the panorama, the image is probably shrinked to accommodate the 16/9 standard width and then enlarged by the zoom function (more 5 times), which brings that poor result.

With a reduced width, everything is as you show, but then it is no more a real panorama...

May be you know a program which would transform a pano directly on a video I could then import into VideoPad.

Thank you for your tests and sorry for the typo !

Regards, Gérard

[deleted]

It's no problem. 🙂 but you are right.

Knowing now that your panorama was 26895 x 2520 makes a LOT of difference and explains your result. It is as you say..with such a width relative to its height the image is reduced to fit across the screen. Consequently you need a higher zoom to get a 16:9 frame to fit into the height of the image for the pan. (I mocked up a "panorama" with repeated flower images to get a high res 26895 x 2520 image)......

Here's the flower image again with a section of the 26895 x 2520 image on the left and the same section from a 16:9 Mpeg4 video made from that image. There is obviously a lot of degredation now.

I think you might be able work around this with a bit of fiddling if you split the original panorama image into say, three or four segments. Place these on the timeline one after another..perhaps alternating track1 and track2 and then panning each one in turn. Might be worth the experiment.

Nat

gaab

Thank you for the tip !

Could be a feature for a future release : start the effect on the original image definition...

Gérard

[deleted]

" think you might be able work around this with a bit of fiddling if you split the original panorama image into say, three or four segments. Place these on the timeline one after another..perhaps alternating track1 and track2 and then panning each one in turn. Might be worth the experiment. "......

I tried this out and it will work quite well but needs some careful cutting up of the big panorama image.(You obviously require a graphics package to do this) You don't need two tracks but each section of the panorama image used must have an overlap on the previous image section so its pan starts where the previous one left off.

e.g. See the mockup below....The first image (part of the big panorama) has panned to the right to finish at the end of the clip. The second image (next part of the panorama) then takes over but the image here must have an overlap equal to the width of the panning area. If correctly set up, the pan effect will be fairly smooth across each of the image sections and the join between the images, where one pan ends and the next pan starts will not be too evident.

A bit of trial and error is needed but each "join" can be checked in Sequence Preview and the position of the Zoom rectangle adjusted so a jump in position is not too evident. The speed of each pan can be evened out if all the image clips are the same length. Using this idea (in the absence of any other and unless anybody can come up with another one) you should be able to pan very wide images that otherwise would be too blurry to use if the whole raw panorama were placed on the timeline and pan/zoomed.

Nat