[MU4 Issue] Zip encoding of MSCZ file doesn't apply compression.

[David-Keeffe]

Describe the bug The MSCZ files from MuseScore 4 don't apply any compression: the contents are all reported as "stored". MS3 uses Flate (Deflate) compression. The consequence is that the uncompressed MSCX component takes a lot of space and the saving of the final file is slow, probably due to the volume of data being written to disk.

To Reproduce Save any file.

Expected behavior An MSCZ file with one of the standar Zip compression technologies applied.

Screenshots Zip report for MS4:

% unzip -v Saint_Louis_Blues_March__Glenn_Miller_-_Brass_Quintet.mscz
Archive:  Saint_Louis_Blues_March__Glenn_Miller_-_Brass_Quintet.mscz
 Length   Method    Size  Cmpr    Date    Time   CRC-32   Name
--------  ------  ------- ---- ---------- ----- --------  ----
   65938  Stored    65938   0% 01-14-2023 08:30 731a8c67  score_style.mss
 6092368  Stored  6092368   0% 01-14-2023 08:30 8df900ca  Saint_Louis_Blues_March__Glenn_Miller_-_Brass_Quintet.mscx
   65937  Stored    65937   0% 01-14-2023 08:30 c613e4af  Excerpts/B�?� Trumpet 1.mss
  263208  Stored   263208   0% 01-14-2023 08:30 d8f7cb23  Excerpts/B�?� Trumpet 1.mscx
   65937  Stored    65937   0% 01-14-2023 08:30 c613e4af  Excerpts/B�?� Trumpet 2.mss

Zip report for MS3:

Archive:  Mas_Que_Nada_-_Jorge_Ben_Jor_-_Brass_Quintet.mscz
 Length   Method    Size  Cmpr    Date    Time   CRC-32   Name
--------  ------  ------- ---- ---------- ----- --------  ----
     186  Defl:N      136  27% 04-14-2021 10:51 0c21a057  META-INF/container.xml
 5177983  Defl:N   110609  98% 04-14-2021 10:51 3230bf1b  score-4e4f22ff7f52ef6780b0ed4152366b1e.mscx
   26624  Defl:N    25584   4% 04-14-2021 10:51 f878bfea  Thumbnails/thumbnail.png

Platform information MacOS 11.7

[krtschil]

On Linux this seems to be ok: Length Method Size Cmpr Date Time CRC-32 Name

---

66243 Defl:N 10028 85% 2022-12-06 14:19 f03a2f70 score_style.mss 135668 Defl:N 5079 96% 2022-12-06 14:19 872ab9b3 Inner_Light_(Piano).mscx 28264 Defl:N 27378 3% 2022-12-06 14:19 fb6ffb6a Thumbnails/thumbnail.png 3088 Defl:N 502 84% 2022-12-06 14:19 b9219c2e audiosettings.json 55 Defl:N 45 18% 2022-12-06 14:19 93e5d13e viewsettings.json 340 Defl:N 167 51% 2022-12-06 14:19 7a1b43e4 META-INF/container.xml

---

233658 43199 82% 6 files

[Jojo-Schmitz]

7Zip on Windows 11 also reports each file within an mscz to use the deflate algorithm:

[David-Keeffe]

I just installed 4.0.1 on my Mac and the non-compression issue seems to have been resolved.

[Jojo-Schmitz]

Strange enough nothing to that extent has been changed

[cbjeukendrup]

Is there still any problem here, or can we close this issue?

[zacjansheski]

Closing