05522: chdman: *CD* FLAC compresion doesn't work for GDI images

ID	Category [?]	Severity [?]	Reproducibility	Date Submitted	Last Update
05522	Misc.	Minor	Always	Apr 12, 2014, 15:06	Apr 25, 2014, 01:58

Tester	MetalliC	View Status	Public	Platform	MAME (Official Binary)
Assigned To	R. Belmont	Resolution	Fixed	OS	Windows Vista/7/8 (64-bit)
Status [?]	Resolved			Driver
Version	0.153	Fixed in Version	0.154	Build	64-bit
		Fixed in Git Commit		Github Pull Request #

Summary	05522: chdman: CD FLAC compresion doesn't work for GDI images
Description	CD FLAC compresion codec doesn't work for GDI images.
Steps To Reproduce	1. Take some Dreamcast image with a lot of CDDA tracks, "Airforce Delta v1.000 (1999)(Konami)(NTSC)(US)[!][1S T-9501NAF]" for example. 2. convert it to chd chdman.exe createcd -i "Airforce Delta v1.000 (1999)(Konami)(NTSC)(US)[!][1S T-9501NAF].gdi" -o "Airforce Delta v1.000 (1999)(Konami)(NTSC)(US)[!][1S T-9501NAF].chd" 3. check percentage of used compression codecs chdman.exe info -v -i "Airforce Delta v1.000 (1999)(Konami)(NTSC)(US)[!][1S T-9501NAF].chd" Hunks Percent Name ---------- ------- -------------- 6,489 9.5% Copy from self 61,890 90.2% CD LZMA 268 0.4% CD Deflate 1 0.0% CD FLAC
Additional Information	Expected a lot of data hunks FLAC compressed, but it is not used, except 1 hunk. I've also compressed this image with -c cdlz,cdzl switch (eg manually disabled FLAC) and got almost the same in size chd as previous -> its not the bug of "info" command, but something wrong during "createcd". This only happens on GDI, for CUE/BIN with CDDA FLAC works fine.
Github Commit

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No.10562 Firewave Senior Tester Apr 13, 2014, 07:31	This just means, that the FLAC compression is ineffective for GDI images. chdman compresses each block with all the specified compression methods and only stores the smallest one.
No.10564 MetalliC Developer Apr 13, 2014, 15:51 edited on: Apr 13, 2014, 16:14	"This just means, that the FLAC compression is ineffective for GDI images" -- indeed, but why this happens ? GDI is just kind of TOC-file like CUE, the data tracks is the same as CUE/ISO/etc one more test case: 1. take TOSEC's "Airforce Delta v1.000 (1999)(Konami)(NTSC)(US)[!][1S T-9501NAF]" from previous example. (I can post direct links to it, but not sure its legal and allowed here) 2. unpack it somewhere so we have such GDI file http://pastebin.com/1hUU0PWE and a couple of auidio and data tracks. 3. take a .cue file http://pastebin.com/rhuX8T7q I've made, save this paste as "Airforce Delta.cue" to the same folder. 4.compress it to CHD from .cue chdman createcd -i "Airforce Delta.cue" -o "Airforce Delta cue.chd" 5. compare resulting file sizes - from GDI - 780Mb from CUE - 637Mb 6. check compression used chdman info -v -i "Airforce Delta cue.chd" Hunks Percent Name ---------- ------- -------------- 928 1.5% Copy from self 15,307 24.3% CD LZMA 265 0.4% CD Deflate 46,585 73.8% CD FLAC as you can see - 73.8% compressed as FLAC, not 0.0% as in the case of GDI ;) note: in both cases used the same data/audio tracks (track01.bin - track30.bin), the difference only is GDI or CUE TOC files used as input for chdman. PS: I've noted one more difference: in CHD from GDI tracks have Tag='CHGT' tag. in CHD from CUE tracks have Tag='CHT2' tag maybe its somehow related to problem ?
No.10565 MetalliC Developer Apr 13, 2014, 17:38 edited on: Apr 13, 2014, 17:40	isolated problem a bit more - compress test GDI image using various codecs: default or -c cdlz,cdzl,cdfl --- result image 780Mb, 0.0% CD FLAC -c cdlz,cdzl,flac --- result image 664Mb 67.9% FLAC so, somewhere is definitelly fuckup in "CD" flac in the case of GDI.