Curious about sega cd size

I was looking at Amazing Spider-Man vs. Kingpin which the size is over 500mb, when I used poweriso then extract the files to a folder. The size was only 94mb.

But that one can be played on retroarch. And the other Amazing Spider-Man vs. Kingpin size 164 kinda play, however no music and skips It isn’t about why there’s no music.

It’s just the size of the game.

Sega CD discs usually have a data track and then a bunch of audio tracks. When you extract the files from disc image you’re only extracting the data track. 9/10 times, the data track is much smaller than the total size of the audio tracks. Some games (not many) only have a data track, and the extracted size is much closer to the disc image size in those cases.

Another factor is that if there are additional languages or other localization changes, the size between the versions from different regions can be very different just from that alone.

If you want to save space without losing the audio tracks you can convert them to CHD with CHDMAN. It’s recommended to use untouched redump images for this.

I have to put a description I have mild aspergers. So I kinda understand but not really.

Because of the full motion plus music? The bin and cue file shows a different size then a iso which has the music to. But 1 is able to play music from retroarch (bin cue) and the iso can’t play the music. But when I use a iso from a genesis emulator the music plus game works perfect.

I’ve seen ps1 games star ocean second story disk 1 (bin cue 545 mb, however the files which I open shows only 400mb. <-- example.

But the Amazing Spider-Man vs. Kingpin when I move the files from the bin file and music. Shows only 57 mb, but the bin file shows 500mb

No worries, and maybe it will help to understand the different types of disc images.

First, be aware that each emulator handles the different disc image types in their own ways. For example, some emulators support ISO/MP3 but some don’t. Some require a CUE file and some will automatically search for the audio tracks even if there isn’t one. So just because it works in one emulator doesn’t mean that the disc image is actually good and proper.

Second, know the difference between redbook audio (ie, CD audio like in music CDs) and streamed or sequenced audio (ie, played from files in the data track).

Common disc image formats:

ISO - Everything is contained in a single file. In most cases, the CD audio isn’t accessible unless the emulator was specifically designed to search for it without a CUE track. ISO is an outdated format for Sega CD and PS1 games (among other systems) and should be avoided.

Single-BIN and CUE - All of the data and CD audio is stored in one BIN file. The CUE files lists the offsets of the CD audio within that file. It also has information about the disc “mode.”

Multi-BIN and CUE - This is the format used by Redump and is the recommended format to use with RetroArch. Track 1 is the data track. The rest (if any) are all CD audio. The CUE file lists all of the files and has information about the disc mode.

CHD - This is just a compressed disc image that stores the audio in a lossless way (FLAC, if I remember correctly). This is probably what most people use these days and most were built from Redump images.

As for the Spiderman example, what you’re not seeing in that BIN file is the CD audio data. The Redump image for that game is close to 600 MB, which is mostly because of the audio tracks. The data track is only around 60 MB or so. It’s very common for the data tracks to be so small compared to the CD audio for Sega CD games especially. A lot of later PS1 games started using streamed audio, so all of the audio is in the data track in those instances (Tekken 3 is a good example).

Thanks but i’m really fixated on the part of why 2 same spiderman games sega cd 1 is 164mb other is 500mb.

Then when I take copy the same data from both (iso and bin) I get the same. Basically just like movie’s, games and other stuff you can’t just move the files then play them because the real information is deep in the cd meaning have to rip them. At anycase i’m just going to stick with bin and cues. It would be a lot easy to understand if I just created a sega cd rom using another rom.

Thank you for your information also taking your time to create this. In other words DUMPING MY OWN GAMES gives you the game of the real size. And another rom site gives you a lesser size same game. Hmm um so the sega cd game it self was around 400 to 700mb of a game? Just like ps1.

Again thank you


The first CDs (Compact Disc) were created designed to reproduce music. They had clues in analog format that was read sequentially with the laser reader, it worked similar to an Acetate LP disc. (Sometimes the separate audio tracks is sometimes noted.)

Then they were expanded to the use of data. SegaCD was one of the first consoles in using them, it was the same for other CD consoles of the time and the first PC games on CD. At that time, music has not yet been added as a digital file (WAV, MP3, ACC, etc.).

The format of the disc was, the first track for the data, where the programmed game was saved and on average occupied very little and the other tracks were music in normal CD analog format.

That’s why when you open the CD on a computer, the files weigh little, because you only read the game programming files. You can also put the CD in a player and listen to the tracks, such as any music CD.

This is something different.

There are record images (without loss) that copied exactly the disc to a file regardless of the content. The game can weigh 140MB, but if a CD weighs 700MB, the disk image will weigh 700mb as well. These images can be compressed (RAR, ZIP, 7Z) and they will spite much less, because the compressor is going to ignore the empty spaces.

There are other images of disk, which compress the content, and there are other images that hack the content so that it enters into smaller spaces. Like the Dreamcast discs that weigh 1GB and you can put them on a 700MB CD.

Sometimes it does not work just copy the files to the computer. The discs like the megacd have a structure, the music files have to be on the site where you are going to look for it, that’s why images of discs are used, because they manage where they have to look for the files.

I get it now. I was using poweriso for that mix mode and dragging the lunar audio 9mb shows up 49mb instead. The game it self is probably 90mb with the audio to. It just creating seems to make the audio 9mb to 49 mb after I wonder why it does that. Really annoying. I want to try burn image just to see the difference but I know it will be the same the audio mb changes.

Do any of you 2 know why?

I also don’t want to try imageburn as has opencandy or malware.

The first CD games, did not have the images, audios and compressed videos, when a compressed disk image is created, you can mark another size.

I have no idea what you are doing. :upside_down_face: I’m sure that online there are good tutorials. Sometimes you will need a specific program, you can not create an image with any program.

FYI, posting links to ROM sites isn’t allowed on this forum, so please edit out that link.

As for why you’re finding different sizes for the same disc image, it’s probably because people altered them in some way. In short: they’re not complete copies.

This is why it’s recommended to use only Redump disc images. They’re verified to be exact copies. Most other formats are not.

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Stone_McCoy I wasn’t asking about rom sites, I don’t want nintendo to go after me… You all have a good day.