Poor resolution of image scaling/zooming

[videxplorer]

Hi,

 

I opened a high resolution (16 megapixels) vertical image in VideoPad, but when I put it on the timeline and use the zoom or scale effect, the quality is not good. I want to do a long vertical pan over the image, but it looks like the resolution of the image is reduced *before* the zoom or scale effect. Is there any way to fix this?

 

Thanks,

[borate]

Is this evident in the exported (produced) file or simply in the preview window, where resolution may be limited?

[videxplorer]

Is this evident in the exported (produced) file or simply in the preview window, where resolution may be limited?

 

Yes it is evident even in the full resolution export, as well as in the preview window : pixel details from the original image are missing.

 

The quality (resolution) is slightly better if I right click the image and choose crop > 16:9 (not using an effect), but then I can not change the vertical offset of the cropped area.

 

Thanks,

[c_major]

Hi,

 

It's a known issue that VideoPad will convert images/videos to output size when importing them. That means if you previewing/exporting at 480p any imported image will be resized to 480p before anything else. You will get better result when you preview/export at higher resolution.

 

We are still working on changing this behaviour.

[Nationalsolo]

HI

 

From the point of view of the preview image appearance, go into tools/option/display and check the Preview Format Preset.settings

 

Set this to the highest values if you want a "clearer" preview image. Note that this may affect the speed of thumbnail rendering and produce warning messages depending on your PC. There is quite difference between 512x288 (16:9) and 1920 x 1080 (16:9)

 

If your image is vertical and you want a vertical pan just use the ZOOM effect.

 

Set Restraint to16:9 and draw the rectangle in to fit the image side to side and then move it to the top of the image.

 

Open the Effects Animation screen. Slide the preview cursor left (start of clip) and set the keyframe markers.

 

Slide the cursor lone to the right (end of clip)

 

Drag the zoom rectangle to the bottom of the image and set the keyframe.

 

Don't alter the size of the rectangle.

 

The speed of the pan down the image will depend on the duration of the image.

 

Export at the higher resolution setting

 

Nat

[videxplorer]

It's a known issue that video will convert images/videos to output size when importing them.

 

Yes! This is the exact problem!

 

I am a passionate photographer and my intent was to present VideoPad in a camera club as a good alternative to slide show programs, because VideoPad allows for precise transition alignment with the music, as well as some interresting audio editing features. However this bug is unfortunate because we cannot zoom into photos without significant loss of quality, which is a show stopper. Any estimate on when this issue might be solved?

 

Thanks,

[Telephony]

Hi,

 

The original image resolution will change based on the effects or exporting settings you use, my suggestion is to play the project from the VideoPad preview window before exporting, to have an idea of what will be exported or if my changes, effects and transitions affected the original image resolution.

 

Also, export first to a local folder, instead of burning directly to a DVD disc, by doing this you will be able to modify the original project Format, Resolution, Frame and Encoder settings.

 

Best regards,

[Nationalsolo]

Hi

 

VP is excellent at producing video slidshows from images and I don't exactly understand where your problem lies as I don't see a deterioration (or hardly any) in the output of a slideshow video. Here is an example. It uses a basic tif image 4480 x 2520 (16:9) of 11meg.

 

This is the ORIGINAL image. On the right is an enlarged part of this image.

 

Loaded to VP I took screendumps of the PREVIEW PANE both UNZOOMED and ZOOMED to match the enlarged area above.

In this example under Tools/Options/General I had the resolution of the preview set at 512 x288 (16:9) which is the lowest preview resolution.

 

 

It's obvious that the zoomed in area of the preview image is not too clear.

 

By re-setting the preview resolution to the highest value 1920 x 1080 16:9 the preview image is much better. Particularly when zoomed in as seen here.. The unzoomed frame looks hardly changed.

 

 

For the best editing resolution it is therefore better to use the higher setting as I mentioned in my post above. (also c-major and Borate) The problem here is that VP has to render the previews etc at the higher value and as a consequence takes longer to do so or even pauses frequently with generating preview messages. It depends on the speed and capacity of your PC.

 

In this test I outputted the zoom sequence as an MPEG4 at the highest resolution of 3840 x 2160 4K

The encoder settings were for the highest quality (1.0) The effect employed in VP was a simple ZOOM into the frame as above, to produce a similar enlargement to the original image. Here are screenshots of frames from the exported MPEG4 VIDEO. On the left the unzoomed section and on the right the zoomed section.

 

MPEG4 Frames

 

 

 

Comparing the zoomed images of the MPEG4 and the original tif (even if they are converted to jpegs and have less pixels than your own) I can't see a particular loss in definition. (If anything the MPEG4 is better.)

This would imply that the screened MPEG4 slideshow would look little different from images shown on screen in a more traditional way;and that's been my experience.

Try the setting suggested and see if you see any difference.

 

Nat

[jotti]

I have the same problem.

 

Seems all suggestions base on exporting the video to a high resolution (3840 width). That takes awfully much time and HD space. Next step would be to reduce the video to something one wanted in the first place. In my case it's 1280x720. Again, that takes time. And something happens to the video and audio quality in each extra turn.

 

In my case I have sheet music that I want to scroll. The sheet music is a 2330x4300 pixel high black-on-transparent png image. If I got it right, VP imports that image and first fits the height (4300) to my video height (720). This reduces the width of the png image from 2330 to 379. Only after that I can fit in the width of the image to what I want. At this point I have to enlarge the image (width from 379 to some 800). So instead of changing the image from 2330 to 800, it goes 2330 -> 379 -> 800. This is when graphic info disappears.

 

Before this gets fixed, I'm tempted to do the following. The Image I want to scroll I scale (in Gimp) to 1280 pixel wide. Then I divide the image into 720 pixel high chunks. Then I scroll each chunk on its own video track in VP. It's an awful mess to get each chunk perfectly jointed to each other, but in my case with sheet music it's not that critical. Lots of white space (or transparent, actually), where the chunk borders can be placed.

[Nationalsolo]

Hi

 

I didn't find scrolling the music across the screen particularly easy to follow visually and as you found joining the scrolling overlays together at precise points is phaffy . I simply scanned the manuscipt and then cropped the image (a .jpg) into line lengths by stave using a graphics program and then placed each of the images on the overlay track in the correct position arranging the next line to quickly dissolve into the next line as the music progressed. This is a typical image from a 720 avi. No problem at all with the resolution of the music line.

 

 

I have done a few like this with no problems. Scrolling each line, as I said, actually makes it quite hard to follow the music.

 

Nat

[jotti]

I just finished editing one video with a scrolling score. It wasn't that much fuss. I used two tracks and five images. Images 1, 3 and 5 on first track and images 2 and 4 on second track. At each joint I just take care that the vertical automation is correct in both joining images. And the resolution is perfect. But this method won't work for the original post problem with photographic images.