Export video quality

Hello Mates,

Can you plz help me whether how can I export my videos while keeping the quality at 1280x720.

When I export my video of 10 or 12 minutes at 1280x720, it takes a lot of time and the file crosses more the 350MB.

What I want is to keep the file size small like what we get at 640x480 but don’t wanna lose the quality we get at 1280x720. I haven’t changed any setting and I have the latest version.

I have already seen a lot of tutorials on youtube etc but none was addressing such issue.

Plz do let me know if there is a work around.

Thanks, and Waiting

Regards

M. Javed

Others will undoubtedly respond from their greater knowledge of codecs and the inner workings of Shotcut; I will respond here from my experience as an engineer knowledgeable in information theory, and its application to real-world problems, of which video encoding is one such application.

Each video frame is an image.
In a 640x480 image, there are 307,200 pixels.
In a 1280x720 image, there are 921,600 pixels. That is exactly three times as many.
So for a starting point, we expect the file size and processing time to increase by a factor of three. A 120MB file becomes a 360MB file.
But this is before compression, and all codecs intended for producing files of a manageable size use compression.
The rule for compression, whether of audio or video or of any information stream is that you can have a great reduction in output file size, or you can have great quality, but you never can have both. This is a mathematical certainty, a law of nature as it were. You can have codecs that do a good job of getting close to that limit, you can have better codecs that get even closer to that limit, but that limit will always be there.
(Others here will hopefully give advice on what codec parameters to use to come closer to that limit.)

As to processing time, it would not be three times longer. Some parts of the processing, of the compression algorithm, will be linear; those parts will be three times longer. But as the process of compressing by creating B-frames and P-frames is done, whole frames must be compared to other whole frames. This will proceed by the rule of size times size, the rule of squares, so those parts of the compression algorithm will slow by a factor of nine.

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What export preset are you currently using? And do you make any modifications in the Export panel > Advanced area? It sounds like simply dropping the Quality parameter on the Codec tab would suffice.

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Dear kagsundaram,

Thanks for being there and I highly appreciate the exemplifications you put to make the sense clearer and I am hoping that someone may have some work around to get the smaller file without compromising the quality.

Best Regards

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Dear Austin,

Thanks for being there.

Well, I am using the default setting of shotcut available for youtube videos and I don’t make any changes to the codecs. I tried the quality parameter but it gone from bad to worse.
I do hope that there is a work around to get the smaller file without compromising the quality.

Best Regards

Hey @mjavedva , I found that your file size is too big and you are having difficulties to store big file sizes, I have some answers but you can’t get a small file size directly it is something long process to do so:-

  1. Check if you are eporting in AVI and if you are exporting in AVI immediately change it to MP4, because avi exports in large size and in most cases you get small sizes in mp4.
  2. Install a third party software like handbrake, etc. and watch tutorials on handbrake or any software for how to reduce file size + software name.
  3. If you have internet faster than 1 mb go to a cloud website like google drive (15gb free space), Dropbox (2gb free space), Mega (50gb free space), etc. and save your file their if you have less storage on your pc.
  4. If you have low internet speed then borrow wi-fi router from someone, because wi-fi routers have faster speed or just get a 5G(100 - 250mbps speed (peak 1GB)) or 4G (10 - 14mbps speed (peak 27MB)) sim.
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Exporting speed could be slow because of your PC specs. For eg :- 4GB ram = 20 minutes to export, 32GB ram = 5 minutes to export.

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I have noticed that also. It makes no difference for small files (I measured that) but for large files I see a big change in GPU usage and disk accesses. The disk accesses no longer come in big bursts. What was happening with 8GB on a large file was the CPU/GPU and the disk were taking turns, with the CPU/GPU waiting idle during each disk access. Now, with sufficient memory (20GB), the OS is using some of that memory for disk buffers, and is prefetching, so that whenever the CPU/GPU needs more from the disk, it is already there in memory.

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I usually don’t feel any lag while exporting because I keep changing my GPUs and more parts of my PC and exports are very smooth for me due to a massive 32GB Ram and 4 Nvidia GeForce RTX 3060 Ti in my CPU, enough powerful for playing Call Of Duty and extensive games (I have to work months to get powerful system in my PC).

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Massive?

I am saving up my dimes and nickels for a tower system with either 128GB or 256GB.

:grin:

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@mjavedva, have you seen the research I posted at Producing minimal, Youtube compatible, file sizes - #2 by kagsundaram ?

The three things I found that reduced file sizes were:

  • Lowering the frame rate
  • Lowering the Quality
  • Raising the GOP size

The first two may be non-starters for you, but have you experimented with a larger GOP? By doubling my GOP from 150 to 300, I had a drastic file size reduction with no noticeable decrease in quality.

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I do also have more ram but not a new motherboard and my this motherboard have 4 slots each 8GB, next time if I will buy a CPU I will get a 16 slot one and add my 128GB chips in them (Buying 128GB*15 chips will take me 5 years, I have 1 chip till now).

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I am up against the same limitation, for now.
And the budget.
I could only pull one pair of my original 2GB DIMMs for replacement with a pair of 8GB units, which is how I went from 8GB to 20GB.

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Hey Ar_D

Thanks for being there and helping.

Well, I am exporting my videos by using the default youtube setting available in shotcut which is mp4.

And, I have well enough storage on my system. Its not an issue and I have 6gb ram installed on my system.

Mostly, I don’t turn my internet connection on while editing and exporting my files as it stops some apps running in the background which saves the system from additional processing.

And I am using i5 first generation dell system. I hope this is not a big issue as shotcut is pretty handy to use in old systems too.

Moreover, I haven’t used any third-party software in this regard and your such suggestion definitely took my attention. And I appreciate your help.

Thank you!

M. Javed

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Thank you kagsundaram! your technical info is really helpful.

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