This may be answered elsewhere but I could not find it.
Could a passionate and patient person please describe in detail, how to export a file that was shot in 4K /and is running at 23.97 FPS?
What are all the little things I should check before exporting?
What is the quality percentage when exporting under H.264 Main Profile and why is it defaulted to 55% - isn’t 100% the original quality of the file and don’t I want to keep it at that quality?
I obviously do not know much but that is why I am asking for help. I hope this doesn’t irritate anyone, I could just use some guidance so I can be a better user of ShotCut. Thank you!
Hi @User12048336e I am somewhat patient and passionate, but I don’t have a huge knowledge about exporting videos.
But I know the experts here will need more information from you:
For example, where will your videos end up? YouTube? Facebook? DVD? Blu-Ray? Or whatever medium or platform is popular these days.
You can change it to 100% which is called “lossless” recording. However, your filesize will be several times larger than at 55%. If you are worried about quality then change this value to 67%. this is what is known as “visually lossless”, which means that for all intents and purposes the human eye should not be able to spot any difference in quality between that quality and 100%, and the filesize will be considerably smaller than the lossless one. Also, some video players cannot handle lossless videos.
When you start Shotcut you should set the video mode to “Automatic”. Then when you open the video file file Shotcut will ensure that the video mode is set to the exact same settings as your video. Opening a video that is in one resolution and framerate in a project that has different settings is not generally a good idea.
So they end up only on a HDD for home use. Basically, I’ll just cut some bad words from a file so they’re watchable for the entire family but didn’t want to lose out on frame rate or that 4K quality.
Oh, thank you for this. I appreciate both of you taking the time to reply.
Interesting, uhm, shouldn’t “lossless” technically result in the exported file size being exactly the same as the original file?
Good to know about the 67%, thank you! That’s very interesting that it works that way!
What is the best format to export to when editing a 4K file and wanting to keep the quality but have a manageable exported file size? Is WMV good? WEBM? I see there are multiple types to export to on the side, which is best for keeping the original quality, but making sure it doesn’t export to the size of 100GB?
I appreciate that ShotCut is very user-friendly but there sure is a fine line before it crosses over to advanced territory - haha!
You’d think so, but that’s rarely the case since most original video has already undergone some form of compression. Here’s a brief explanation as to why. It refers to the GoPro but the principle is the same:
Check that you have a 4K monitor or Television before you start otherwise you’ll be watching in a downscaled resolution and will have wasted all that time.
If you are making for youtube, keep in mind that most people watching yt don;t have 4k monitors so Exporting in 1080p is all that is practically needed.
Your original video will be compressed, i.e. some data has been thrown away to keep the filesize reasonable. If you bring this into Shotcut , the app will decompress the data and try to recreate the data that was thrown away, but it won’t be able to do this perfectly - this is because of the original “lossy” compression.
If you then export it with 55% quality Shotcut will (lossy) compress it again, throwing away more data and you’ll end up with a reasonable filesize, but a slightly worse quality than the original.
If you request 100% quality, the algorithm does not throw away any data, however the file size will be very much larger, since no data has been discarded.
If you export it with 67% quality, again data will be thrown away, so the file will be a reasonable size, but the changes to the video as a result of this should not be detected by the human eye.
Regarding format: I would use the default (MP4) with the h.264 codec. If you want better compression that takes longer to export you could try the HEVC codec, however quite a few Windows users have complained of choppy playback of HEVC-coded videos. See here:
I confirm that the export for 4K video in HEVC (67%) works very well. Very good quality for a very reasonable video weight; for example 21min 4K HEVC(67%), AAC256, 163MB
At equivalent size, an H264 export is of lower quality (and it shows!)
Since a few weeks I have been using HEVC, for export and also for screen capture via OBS. It’s better than H.264. And even for shotcut whose timeline is more fluid (this is also due to better management of B-frames - without b-frame on recording - for HEVC, and GOPs)
Capture HEVC : 453MB - 31min (14.61MB/min)
Export HEVC67%: 163MB - 21min (7.76MB/min)
No visible quality difference between capture and export
Thank you, that is great information to keep in the front of my mind. I am watching on a 4K panel and it’s just for personal use. I’ll ask this further down the page as well but, when I edit a 4K file that is over an hour long, I have severe stuttering issues in the preview window. I checked task manager, nothing is being overloaded, is there any way to fix this?
Oh, I see, thank you! Boy, video formats are such a fascinating concept… Thank you for taking the time to write all that out for me, all of you, in face, thank you for helping me with this, you all have been very patient with a matter I am sure is quite common knowledge.
When I go to export, I see the presets on the side, but I see multiple H.264s. Baseline, high and main profile, which do you suggest?
Oh, thank you, the other person suggested H.264, but if you read this, mate, I’ll just try both to see which works best for me. I have a finicky television which SOMETIMES reads MP4 files and sometimes does not… (EDIT: after re-reading your comment, I see you also spoke about HEVC, haha!)
I think you sort of touché don this about the video previewed being stuttery? I am going to paste a question that I asked another user:
" I’ll ask this further down the page as well but, when I edit a 4K file that is over an hour long, I have severe stuttering issues in the preview window. I checked task manager, nothing is being overloaded, is there any way to fix this?"
there are several answers to be made.
The choice of recording and export codec are not necessarily the same.
First of all, this depends partly on your hardware, its ability to process clips during capture, video/audio processing, then export.
Capture: Today if your hardware is HEVC compatible, if you’re doing 4K, then go for it! Otherwise, H.264 works just fine everywhere (although a bit more hardware intensive)
Otherwise take the recommended format of your video source (video recorder)
Video editing: If shotcut take the format / codec, then you stay in this format, otherwise it will have to be converted to a format without loss of preference. To make shotcut work well (smooth), you can look at the side of the reduced preview, and also proxies - both of these solutions can improve the performance of shotcut.
For my part, I regularly work in 4K (H264, today in HVEC) and the preview remains fluid, unless I add text, filter… at this point it lags… it’s normal! In 1080p@30fps, it’s better but it also happens that it lags. Real-time processing is a difficulty for editing software (I don’t know if a software can read effects on a video in real time; it seems to me that in this case, there is a buffered render before playback …)
and I have a very good machine…
I use the reduced preview from time to time.
Export: here it all depends on the destination of your video. So you can make a lossless video for your archives, a reduced one for youtube, another very reduced one to send to a person via a link…
There is as much use as reason to export the same video in several formats/codecs/quality/sizes…
HEVC: is best for 4K
H.264: goes everywhere, ideal for 1080p
For each choice of codec, you can choose settings for the quality of the output video.
Baseline = base configuration
Main = goes everywhere, with normal compression
High = good quality (almost no difference with the source, but slightly degraded)
For a typical video you make, do an export test with the three profiles, and see what suits you best in terms of quality and file size.
And you can redo other profiles… but you have to know the parameters and values in the “Other” section
For my part, for quality issues, I made profiles with the value 67% for quality.
Each of these profiles defines the specific encoding techniques and algorithms used to compress files.
Baseline Profile
This is the simplest profile used mostly for low-power, low cost devices, including some videoconferencing and mobile applications. Baseline profiles can achieve a compression ratio of about 1000:1 — i.e. a stream of 1 Gbps can be compressed to about 1 Mbps. They uses 4:2:0 chrominance sampling, which means that color information is sampled at half the vertical and half the horizontal resolution of the black and white information. Other important features of the Baseline Profile are the use of Universal Variable Length Coding (UVLC) and Context Adaptive Variable Length Coding (CAVLC) entropy coding techniques.
Main Profile
Main Profile includes all of the functionality of Baseline, but with improvements to frame prediction algorithms. It is used for SD digital TV broadcasts that use the MPEG-4 format, but not for HD broadcasts.
High Profile
H.264 High Profile is the most efficient and powerful profile in the H.264 family, and is the primary profile for broadcast and disc storage, particularly for HDTV and Bluray disc storage formats. It can achieve a compression ratio of about 2000:1. The High Profile also uses an adaptive transform that can select between 4x4 or 8x8-pixel blocks. For example, 4x4 blocks are used for portions of the picture that are dense with detail, while portions that have little detail are compressed using 8x8 blocks. The result is the preservation of video image quality while reducing network bandwidth requirements by up to 50 percent. By applying H.264 High Profile compression, a 1 Gbps stream can be compressed to about 512 Kbps.
Thank you for this question…it is something I had not considered before…I have just used the default settings…and after playing with a few of them, without a clue as to what they are…I can conclude that the defaults are good enough for me
On my Mac Pro 5.1 with jsut 32Gb RAM I have tried all defaults just now except for the Quality percentage.
No editing of the file I jsut dragged a video clip from the phone to the edit window, then exported.
a 37mb clip at
15 at 2,7mb
25 at 4mb
55% comes out at 25mb
65 is 43
75 at 73 a
100% at 325 and my mac cannot play it…not even a preview icon
for my viewing on a 14 year old 42 inch plasma screen, uploading to youtube or FB or computer viewing I can safely go down as far as 25-30 % quality
at 15 % there are noticeable blocky artefacts but above 20-25 there is no noticeable quality difference on the screens I am using…wit the advantage that I can save large amounts of space.
Any other export options I try, like the hardware encoder, it detects two (h264videotoolbox and havc video toolbox) and always ends up with a failed export…
Interesting to see the options, liek all the different codecs…but not found anything else except the default that actually works and creates a proper export
Thank you very much for this, I think it really helps. I apologize for my lack of knowledge but I appreciate you all being so patient and helping me.
Okay, and so here are my specs for the computer and yet I still get stuttering when previewing 4K footage despite haven’t scaling and proxy on and when I am editing, my CPU SPIKES and it uses all my RAM.
i7 9700K
GTX 1080
32GB 3200MHZ Memory
I’ve looked on the forums with people having similar issues but they all seem to have obviously underpowered systems for what they’re doing. This should be adequate, right? And yet I have the stuttering while editing and the spiking of CPU and RAM while editing and exporting. I don’t run any other programs, CPU is at 5% when i open Shotcut, I always do a restart before editing so I don’t know what to do.
I have tried reinstalling, installing to the C drive, which is an NVME. Any ideas on how i can make editing a smoother process and to make exporting more efficient?
Oh, interesting, thank you for sharing! Do you enjoy editing on your Mac? Do you think someone who has ShotCut saves on a windows drive could transfer them to a Mac and pick up where they left off on a windows computer?
