Question about CHDMAN

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Just wondering if anyone knows the answer to this wihtout me having to go test it...

If I have a game on a 40 GB Harddrive and I made a CHD file with it and I also have the same game on a 20GB harddrive and make a CHD file of it, will the files be different sizes?

Meaning if you try to dump a game from a 40GB drive will it make a bigger CHD file then a smaller harddrive would? or Does CHDMAN only grab the actual data on the disk and make the chd file?

I only ask because I just dumped a BBH drive from a 40GB drive and the CHD file is about 1.6GB. Is there a way to reduce the size of a chd file to take out any blank data?
I looked at the file in a hex editor and there isnt and FF blank bits, but there is a large amount of this:
 

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The entire disk is ripped into an image file and then compressed. So before compression the 20GB disk would result in a 20GB file and the 40GB disk would result in a 40GB file, but there would be very little difference between the two once compressed.

In most cases you could probably create a small partition, copy all the files into it and then make an image of it, but it would be pointless. Blank sectors of a disk take up very little space.
 
I think what's being asked is can you take a 40 gb CHD and drop it on a 20 gb hard drive, right?

I'm going to lean towards no, unless you can zap out all the blank data somehow.
 
I think what's being asked is can you take a 40 gb CHD and drop it on a 20 gb hard drive, right?

I'm going to lean towards no, unless you can zap out all the blank data somehow.

Sorta yes, I was hoping that CHDMAN doesnt include all the extra space in the chd file. I seems like it does. I made a CHD file from a 40GB BBH drive that came out to be 1.5GB .
I made the CHD of BBH shooters challenge from a 40gb drive and tried to write it to a 16GB drive and it ran out of space. Its possible that BBHSC is larger than 16GB, but I have Golden Tee complete and GT2005 on a 16GB drive and BBHSC is older then those games and I doubt its larger than 16GB
 
In that case you are going to have to uncompress the CHD (chdman -extract), mount the image it creates, extract the files from it and copy them over manually.
 
In that case you are going to have to uncompress the CHD (chdman -extract), mount the image it creates, extract the files from it and copy them over manually.

Im not sure you have dealt with arcade harddrives (file structure). I dont think that is possible to do (I'm not an expert though)
 
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