Resolution question

Hi everyone… Ok, so I have a video, when I cmd-i it in the finder, I see: 640 × 480 AAC, H.264

… I open shotcut, and start a new project with SD NTSC, drag my video in, and under properties it says 720x480. Why does the finder say 640 and shotcut says 720?

720x480 is the actual, stored resolution of the broadcast and DV standard… but with non-square pixels. Depending upon the pixel/sample aspect ratio that same stored resolution can be either a 4:3 or 16:9 display aspect ratio. When the 4:3 stored resolution is converted to square pixels for display on a computer that is using square pixels, it becomes 640x480 – achieved by scaling it (compare 640 :heavy_division_sign: 480 with 4 :heavy_division_sign: 3). When it is 16:9 aspect ratio (a.k.a. anamorphic widescreen), it becomes 853x480 or 854x480. Welcome to the oddities of video.

P.S. If you want a 640x480 video mode instead of using the broadcast standard, you can use Settings > Video Mode > Non-Broadcast > 640x480 4:3 NTSC (where NTSC only refers to the broadcast frame rate).


Thanks for the reply. So, this video, when I displayed it on my projector, I realized it looked squished (4:3), and so when I told VLC to set the aspect ratio to 16:9, it looked correct… But, if I re-export on shotcut with 16:9, then it just puts black borders on the side. And the same thing happens if I manually set to 854x480 keeping 4:3, or change video mode to “DVD Widescreen NTSC”

What do I need to do to tell shotcut to stretch the video to fill a 16:9 aspect ratio, not add black bars as padding?

I can fix this with ffmpeg, but just am curious how I would do it when exporting in shotcut…

in Shotcut, open or select clip and change Properties > Video > Aspect ratio

Aha! Great, thank you!!!

One last question-- if I am planning to burn to DVD the videos made in shotcut, should I be setting scan mode to interlaced?

Actually, I still seem to be quite confused about aspect ratios… So, I have a video, which again, the finder says 640x480… If I inspect the properties in quicktime it says 4:3, and says the resolution is 720x480, but it says “current size: 720x540.”

When I view the original footage in full screen mode in quicktime and VLC, the original video takes the full height of the screen, and there are small black bars on the sides (which I expect for 4:3)…

When I bring the original footage into shotcut, it says the resolution under properties is 720x480 4:3, though when I export it out and view that video in full screen, it has black bars at the top and bottom as well as the sides…

I tried exporting 640x480, 720x480, 720x540, and they all look wrong… I tried adding a “size, position, rotate” filter and setting the height to 540 (to match what quicktime said “current size” was), and that looks wrong too… What am I doing wrong? Why am I getting black bars at the top and bottom when I export?

Could be a number of reasons. Maybe the aspect ratio is not being interpreted correctly. Maybe the black bars are actually in the video.

Can you share a screenshot of the whole Shotcut window with the clip properties panel showing?

Also, show us what video mode you have selected in this case.

sure thing… Here is the shotcut screenshot of the original…

And then VLC playing the exported file:

As you can see, even in the preview on shotcut, the video took up the entire height of the preview area… Yet in VLC, there are those black bars above and below…

and these are the settings under export that I did:

Can you also show what Video Mode you have set?

ProTip: never change parameters in the Advanced export settings. The advanced export settings will match the video mode unless you override them. And there are rarely reasons to override them.

Agh! I just realized, I didn’t answer you about the video mode, and sure enough that was my problem… I had “widescreen DVD NTSC” selected, and changing it to 640x480 seems to have fixed this…

So, then I just am back to my last remaining question… If I am going to burn to disc, do I want export to be “interlaced” or “progressive”?

Your screenshot shows that your source files are progressive. So I would stick with that. DVD supports either.

Also, DVD resolution is usually 720x480 - still 4x3 in your case.

thank you so much for the help and insights everyone.

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