Exporting .cbh to .png

There are a number of free chess databases on the net; is it possible to extract or export one (or more) games in the .cbh folder to a pgn? I find it easier to make commentary when opening the pgn in Tarrasch.

Thanks for your help.

I think you mean exporting to pgn, not png.

In order to convert from one format to the other, you need to have a program that recognizes the cbh format.

cbh is a ChessBase format.  It's a proprietary format to store their databases.

ChessBase Light (free) can do the conversion, but there might be a limit to the size of the database that ChessBase light can open.  Using ChessBase Light, once you open the database, highlight the games you want and RIGHT CLICK on the selection (you will not find the option you need in any of the upper menus).  Select "Output > Selection to text file".  You should be able to take it from there.

MrEdCollins I have legal Chessbase 14 with Mega Datebase 2017 which have over 6.8 milion games and i tryed to method you mentioned selected all then >Selection to text file< and exported PGN format but it only exports 2.2 milion games i can't finde way to export all games, i want to use this datebase for other chess program

I think ChessBase 14 has a technical limitation of exporting and inporting 2GB pgn-files. And I have seen exactly the same limitation with ChessKing 5 and Aquarium 2017. I have contacted ChessBase support multiple times about this isse but they don't even bother to answer my mails, even though in the last mail I explicitly asked them to reply so I could know that they have received it. No reply at all.

This is a problem of Windoze, not Chessbase.

Did you try to alter the %TEMP% environment variable before trying to import/export such huge textfiles?

pfren: I have 32 GB RAM on my computer and I run with 64 bit Windows and the 64 bit version of ChessBase, so this has nothing to do with Windows but is a plain limitation of Chessbase probably because Chessbase use 32 bit integers to keep track of file seek positions, instead of using the 64 bit version of the Windows API's in question. This might be due to a limitation in some third party library that they might use (I don't know), but it is still ChessBase's limitation (problem). Problems like this is typical for software with an old codebase that has been in use since before Windows came out with general 64 bit support.

OK. What about splitting the cbh database to smaller chunks first- e.g. by ECO codes to five parts?

Yes, splitting the file/database is exactly what we must do, but this can can be difficult and takes lots of extra time/manual work, which should have been done by the software. I mean, take the pgn-files from http://ficsgames.org/download.html for example, now I must download monthly instead of yearly files to get them small enough to be importable to ChessBase.

The nice thing, thought, is that ChessBase 14 seems to handle real, real huge databases with no stress. It is only a problem during import/export. My database is now at almost 60 million games and ChessBase seems to handle it just fine. Barely finished with 2007, thought, so there are probably still a hundred million games or so to go...

Can't you download the whole file at once?

I have not found a way to download the whole database at once. And if I could it would be too large to be imported into ChessBase since ChessBase has that import file size limit of 2 GB.