MS 2.0.2 mscz file sizes 4-6 times larger vs MS 1.3

• Nov 10, 2015 - 07:22

I'm just curious but avaragedly the file size of an in 2.0.2 imported mscz 1.3 file grows between 4 and 6 times only by re-saving it while nothing has been changed. Is this to be expected?


Not the case here, I've just tried, the 1.3 file is 13kb, the 2.0 file (opened the 1.3 file in 2.0.2 and saved it) is 28kb, so roughly double the size, but pretty far from the 4-6 times you see.
19k of that increase are due to the thumbnail image in the 2.0 file, these didn't exists in 1.x., so the actual file (the mscx) even got slightly smaller (from 229k to 216k in this case)
For smaller file of course the thumbnail takes a larger Proportion, so yes, there I can see a 4k to 14k increase, 11 of which are due to the thumbnail.
So for really large scores you should even get (slightly) smaller files

In reply to by Jojo-Schmitz

I like to come back at this issue. The 4-6 times larger size for 2.0.3 vs 1.3 is default if you use single page fake book files. If an thumbnail image is added of 19kB and the original files vary between 4kB and 8kB it is understandable. What for is this 19 kB thumbnail image used?
I added an typical example for .mscz: 6kB (V:1.3), 26kB (V:2.0.3) and for .mscx: 121kB (V:1.3), 101kB (V:2.0.2). see: Blue And Broken

Using ca 670 embedded files in our The New Bob Book.pdf (… ) where you can jump from any pdf song to the MuseScore app or jump to the iReal Pro app opening directly the corresponding song (now Only in Android) the total pdf size is ca 39MB. Getting rid of all the useless thumbnails should save 13MB.

Question: can I get rid of this thumbnail in a .mscz file?


In reply to by Robipad

The thumbnail is used in the MuseScore Start Center and is paving the way for score preview in operating systems (Windows / macOS). The latter is still work in progress.

To my knowledge, it's not possible to not save a score without the thumbnail. Is 13MB really the issue?

In reply to by Thomas

Hi Thomas,
Downloading is slowing down all the time these files grow, so we try to keep the size as small as possible, so if there are possibilities to minimize sizes we try to implement it. But of course if it is not possible it is not a disaster. In this application I don't think the preview makes any sense, so if there were a simple solution to prevent adding it during the conversion/export it would be helpful.


In reply to by Robipad

The thumbnail is part of what makes an MSCZ an MSCZ and not an MSCX. If you don't want the thumbnail then your best bet is to save as MSCX and store your MSCX files inside a compressed (zipped) folder, or enable filesystem compression of the MSCX files if your operating system and file system support it.

In reply to by shoogle

The attached files will directly be opened in the MuseScore songbook which will only accept the MSCZ format. So zipping is not an option. The MSCZ file from 1.3 does not contain the thumbnail. So basicly it is not necessary to include the thumbnail. It is a understandable choice to include the thumbnail and for the more complicated files with more pages it hardly plays a significant role in the size. Only the files I use are very small mostly beïng one page fake book songs in which case the size is mainly dictated by the thumbnail.

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