add CHD support

[bigboo3000]

Hi Beetle psx now has CHD support, it would be great if pcsx_rearmed had CHD support as well. It's the only PSX core usable on RPI or old PCs.

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[KMFDManic]

First of all, thanks so much @notaz for the great PicoDrive, and coming out of pseudo retirement to add some nice changes to the code, and @twinaphex for all the work you have been doing in your personal time, libretro wise! Being that chd support has been added successfully for Genesis Plus GX, Mednafen PCE-Fast & Mednafen PC-FX, I would absolutely love to push for it to be added for pcsx_rearmed/neon. I would love both of your opinions, as far as reasonable expectations, of this being achieved...if I post a bounty for it. I am hoping to get chd support, additionally, for 4DO and Yabause. I will have no problem getting a few people involved in bounties for these. PicoDrive would be nice to have chd support, too, if it isn't too much of a hassle! But, thanks to both of you, and I look forward to seriously getting this done, if you guys and anyone else involved do not mind doing it for a bounty! Thank you in advance for your feedback. I am hoping to get the bounty posted, today, once I get a proper response from you:)

[Darknior]

Yes CHD is the best ISO format :) I dram to see it on all the systems like 4DO, Yabause, etc... like you write. But on PSX it is not the same, we already have the perfect PBP format. I convert all my ISO in it and it works very fine ;)

[KMFDManic]

CHD has better compression than eboots do. CHDs are also very easy to batch convert with a script I did.

[Darknior]

Ok i don't know it as a better compression, and it will works fine on PI ?

[KMFDManic]

Yes, it will. Space being a major factor, on the format I run them on, is why CHD takes priority over Eboot. But, yes, CHD would work on Pi.

[Darknior]

Ok ... wish some one add it to all RA core :) And some one other create an easy program to convert ISO of all these systems to CHD ! For the moment i don't use CHD, only on Dreamcast.

[KMFDManic]

I already made an easy setup to convert to CHD:)

[Darknior]

Excellent, where can we DL it ? have you an url please ?

[KMFDManic]

I will post it for you shortly.

[MajorDangerNine]

@Darknior I made the CHD step-by-step below a little while back, but it only converts the ones with a ".cue" or ".gdi".

https://redd.it/72kh6q

[Darknior]

Thanks a lot @Eckaji , i will try it :) So cool if i can save place for Sega and Nec games. PSX like you write i like PBP for multiple CD games ... I wish it will come also for 3DO and other CD systems ...

[kidburglar]

Helllo, It would be realy a good way to gain space. I just looked how to convert existant bin/cue files to pbp and it's a complete hell... Thanks for your work and I hope see chd support added soon

[bebess]

it would be so great...

any update ? i do a request https://github.com/notaz/pcsx_rearmed/pull/107

[nosh01]

Bump!!!!!!

[andres-asm]

This is not 4ch. Bumping doesn't achieve anything other than annoying people.

[nosh01]

Wellll maybe I'll contribute to a bounty, I would assume that wouldn't trigger anyone.

[bebess]

@KMFDManic , do you have any news from @notaz and/or @twinaphex ? I'm totally ready to start a great bounty , i have created a new https://github.com/libretro/pcsx_rearmed/issues/170 for better visibility

But i'm waiting ... an answer...if someone "can" do the request

[gt46l]

Something no one has mentioned yet, but PBP is a lossy format. You can't convert from a PBP to other formats with with 100% quality of the original, or playable on the original hardware at all, because it destroys the original format and converts audio/video to lossy versions. CHD on the other hand is a non-lossy archive quality format that you can convert to any other file format playable on emulators or hardware. CHD is the only format I would want to save 1200 roms in, even if I intended to use some in other formats.

[ghost]

i wish.....

[VGkav]

PBP is not a lossy format, you can extract the game files and they will be byte for byte identical. Saying it converts audio and video to lossy formats is false, I'm pretty sure it just gzips.

CHD does LZMA and FLAC compression, that will increase the performance/memory impact a lot and introduce new audio bugs, as if there aren't enough already.

[gingerbeardman]

PBP is not a lossy format, you can extract the game files and they will be byte for byte identical. Saying it converts audio and video to lossy formats is false, I'm pretty sure it just gzips.

I understood that you could get lossless files back out of an EBOOT.PBP but you could not get the original CD BIN/CUE back out of it (as yo van with CHD) so it's lossy depending on your source format? https://www.psdevwiki.com/ps3/PlayStation_archive_(PSARC)

CHD does LZMA and FLAC compression, that will increase the performance/memory impact a lot and introduce new audio bugs

What are you basing this on? It makes no sense to me. Why would a proven compression scheme with reference/OSS decompression code cause audio bugs?

[negativeExponent]

as far as i know, CHD should already be properly supported. so this can be closed.