New Shotcut user, trying to do a VERY basic edit, but when I export the video has been shrunken a bit and I can’t figure out why.
What I’m trying to do:
I have a video (about 20 seconds) with a stereo audio track. I’m trying to replace the audio track with an alternate 7.1 track. I had been using OpenShot but OpenShot has a bug with exporting in surround sound so I figured I’d try Shotcut.
So I opened the original 1920x1080 video, separated out the audio into its own track then deleted that track so I was just left with a silent video-only track. Then I imported the video clip w/ the 7.1 audio into a new track, again separated out the audio but deleted the video track. In the properties of the video track, I set the audio to “none” and in the properties of the audio track, I set the video to “none”. The video is 1920x1080.
When I go to export, I choose H.264 “high profile”. Resolution and Ratio are both set to 1920x1080. FPS is 24, just like the original. Deinterlacer is YADIF temp + spac, Interpolation is Hyper/Lanczos. CODEC is libx264, Rate control = Quality-based VBR, quality 100%. In “Other” I set “channels=8”. “Video mode” is still set to “automatic”. I don’t see any funnels to suggest I accidentally applied a filter.
I’d estimate the resulting video is about 25% smaller than the original, although VLC says the video is still 1920x1080, so it has a black border baked in and the smaller version is burned into a 1920x1080 frame. At least I’m getting my 7.1 but I’d like the original video to come out as close to original as possible.
And welcome to Shotcut! So you are trying to do a VERY basic edit but when you export the video, the video shrinks, right?
Looks like you are trying to render at 1920x1080. I render most of my vids at 1920x1080 so I think I can help. I have attached an image to this reply. Next time you open Shotcut, would you kindly screenshot your New Project settings for me and upload them to your reply?
Actually I don’t think I have to (it’s set to “Automatic”) I think that answers all my questions. I see it says there that it means the resolution is based upon the first video I add. I’m pretty sure I added the 1920x1080 one first.
So I started over, adding the 1920x1080 one first, and redid everything. It exports fine now. Live and learn!
I have some Quadro cards installed so I experimented with using nvenc for the exported video (H.264) vs. CPU. The export went exponentially faster, the file size was like 9MB vs. 170MB and the quality was WAY down. As far as I could tell, all the export options between the two were the same (I can do screenshots later if necessary).
Is there something intrinsically different about nvenc that would cause this, regardless of settings?
Shotcut seems to have a LOT more features than Openshot, but not the same kind of intuitive “just dive in and use” experience so I’ve got a lot of learning to do about its nuances and quirks.
Video hardware encoders in PCs are designed for speed of encoding, at the expense of file-size (they usually produce a much bigger file), and quality (they usually produce much lower quality videos). They are perfect for streaming, but not for producing quality videos.
Screenshots of the Codec and Other tab export settings would be very useful. It would also help if you could attach the job log of a completed NVENC export so we can verify which settings actually got used. In the Jobs panel, right-click the completed job and click “View log” and send the contents as a reply or an attachment.