All my exported videos looks blurry with lower quality

[D.Dave]

Hi, first of all some info about my environment:

OS: Manjaro Linux 64 bit
CPU: Intel Core i5-3210M (2 core+2 threads, total 4) maximum frequency 3100Mhz
GPU: Intel HD Graphics 4000
Ram: 16GB DDR3
Samsung EVO 860 SSD 512 GB

I record my laptop’s screen at 1366x768 resolution, 60 FPS, in mp4 format, and the result is very good: smooth and high quality results.

I import them in Shotcut (v.20.11.28) to add images and some A/V filter.

I tried any preset for exporting:
Lossless H.264, HuffYUV, Ut Video; ProresHQ, H.264 High Profile; I also tried to manually set the bitrate costant at higher values; the GPU also supports vaapi HW enc.

But I always get poor quality video files.

Info of the files which I record:

General
Complete name                            : /run/media/dave/TOSHIBA EXT/screenrecord/simplescreenrecorder-2020-12-08_21.26.17.mp4
Format                                   : MPEG-4
Format profile                           : Base Media
Codec ID                                 : isom (isom/iso2/avc1/mp41)
File size                                : 87.6 MiB
Duration                                 : 5 min 49 s
Overall bit rate mode                    : Variable
Overall bit rate                         : 2 101 kb/s
Writing application                      : Lavf58.45.100

Video
ID                                       : 1
Format                                   : AVC
Format/Info                              : Advanced Video Codec
Format profile                           : High@L4.2
Format settings                          : CABAC / 4 Ref Frames
Format settings, CABAC                   : Yes
Format settings, Reference frames        : 4 frames
Codec ID                                 : avc1
Codec ID/Info                            : Advanced Video Coding
Duration                                 : 5 min 49 s
Bit rate                                 : 1 990 kb/s
Width                                    : 1 366 pixels
Height                                   : 768 pixels
Display aspect ratio                     : 16:9
Frame rate mode                          : Variable
Frame rate                               : 60.000 FPS
Color space                              : YUV
Chroma subsampling                       : 4:2:0
Bit depth                                : 8 bits
Scan type                                : Progressive
Bits/(Pixel*Frame)                       : 0.032
Stream size                              : 83.0 MiB (95

Exported file info (in this case, as example, using HuffYUV export profile):

General
Unique ID                                : 142134193965410111146725063702138064141 (0x6AEE0CCEA16EC90E842156BA15E00D0D)
Complete name                            : /run/media/dave/TOSHIBA EXT/Exports/exportedvideo.mkv
Format                                   : Matroska
Format version                           : Version 4
File size                                : 14.7 GiB
Duration                                 : 6 min 8 s
Overall bit rate                         : 342 Mb/s
Writing application                      : Lavf58.45.100
Writing library                          : Lavf58.45.100
ErrorDetectionType                       : Per level 1

Video
ID                                       : 1
Format                                   : HuffYUV
Format version                           : Version 2
Codec ID                                 : V_MS/VFW/FOURCC / HFYU
Duration                                 : 6 min 8 s
Width                                    : 1 366 pixels
Height                                   : 768 pixels
Display aspect ratio                     : 16:9
Frame rate mode                          : Constant
Frame rate                               : 60.000 FPS
Color space                              : YUV
Chroma subsampling                       : 4:2:2
Bit depth                                : 8 bits
Scan type                                : Progressive
Default                                  : Yes
Forced                                   : No
Color primaries                          : BT.709
Transfer characteristics                 : BT.709
Matrix coefficients                      : BT.709

Audio
ID                                       : 2
Format                                   : AAC LC
Format/Info                              : Advanced Audio Codec Low Complexity
Codec ID                                 : A_AAC-2
Duration                                 : 6 min 8 s
Channel(s)                               : 2 channels
Channel layout                           : L R
Sampling rate                            : 48.0 kHz
Frame rate                               : 46.875 FPS (1024 SPF)
Compression mode                         : Lossy
Delay relative to video                  : -21 ms
Default                                  : Yes
Forced                                   : No

I taked a screenshot of a portion of the videos: the original one and the exported one, the problem of the quality is clear.
On the left there is the original video; on the right the exported video:

I miss something? Can I have some hint/suggestion to try?
Obviously I don’t pretend to have a 1:1 copy, but the result is not good, and I am sure is a mistake of mine.
I have a lot of disk space (I also have another 5TB disk), so I don’t care of the file size (eg the ProresHQ preset gave me a 14.4GB *.mov file, but the quality was however low)
Thank you.

[pdr]

You mentioned “to add images and some A/V filter.”

Which filter(s) did you apply ?

Does the preview look ok before exporting ?

[Hudson555x]

This might be expected using variable fps footage.
Change settings or find a recorder that records with constant frame rates.

As you can see Shotcut padded the video with extra frames to make up for the variable fps.
Shotcut does not export a variable FPS.

Shotcut tries to detect variable fps media, in an attempt to have you convert it using Edit-Friendly, which may resolve the issue you’re having. You may have seen this pop-up when you opened your video in Shotcut.

Use this converted version in place of your original file for your project.

Best to start off with the default export settings, don’t enter advanced. If you change settings in Advanced you’re going to have unexpected results based on what you change. There is a warning explaining this before entering into Advanced mode.

[D.Dave]

@pdr

You mentioned “to add images and some A/V filter.”

Which filter(s) did you apply ?

Does the preview look ok before exporting ?

voulme gain and videos fade in/out.

However I figured out that I had to set the video mode manually instead of rely on automatic: I set it to the same as the laptop screen (1366x768 at 60Hz/FPS) and now has been properly encoded.

[D.Dave]

Many thanks for the detailed and interesting reply!
However, as you can see in my previous reply, I solved by just manually set the video mode in Shotcut’s settings.