MP3 player for MSX | MSX Resource Center (페이지 7/51)

Paragon (1839)

27-02-2007, 12:36

Well, I was only thinking about converting existing AVIs, MPEGs whatever, not creating new own movies The Dragon's Lair movie is a conversion, too, isn't it? But if I understand you correctly, Dragon's Lair is a very special kind of movie and you won't have this quality with other movies?
Hm, maybe Screen5 showing a smaller frame would be an alternative. But sorry, it starts to become offtopic now

By wolf_

Ambassador_ (10092)

27-02-2007, 12:41

I was indeed talking about new movies for gaming purposes. -btw, don't mind any offtopicness, welcome to MRC-

By Prodatron

Paragon (1839)

27-02-2007, 12:59

Thanx a lot for the information!

By Vincent van Dam

Hero (513)

27-02-2007, 15:21

Dragon's Lair was animated by Don Bluth. Don Bluth, once a disney animator, also made the movies Titan A.E. (2000) and Anastasia (1997).

By [D-Tail]

Ascended (8263)

27-02-2007, 15:21

so that means you need a HD or Cf card in your msx in order to store mp3s ?

I guessed the msx would send a signal to the cart, and have an output of some kind..
or the msx'es one

Yes, you need a HD of CF for storing the MP3's.
Maybe Obsonet will give you MP3 radio, but i think it's speed is to slow for it.
But i am not sure.Well, a small note about this: Matra is involved in Dumas. Dumas will contain Obsonet. It will not use any Z80-time, because Dumas has its own co-processor and moreover: Matra could look into combining this MP3-player with Dumas/Obsonet.

By Prodatron

Paragon (1839)

27-02-2007, 15:34

@Dennis: Would it be possible to do the "need audio data" signal/interrupt more early? Originally I was planning to check the status every 1/50s seconds, but this wouldn't be enough when playing a 128kbps MP3. 512bytes would be better in this case.

By Prodatron

Paragon (1839)

27-02-2007, 15:40

Well, a small note about this: Matra is involved in Dumas. Dumas will contain Obsonet. It will not use any Z80-time, because Dumas has its own co-processor and moreover: Matra could look into combining this MP3-player with Dumas/Obsonet.

If Obsonet is able to "load" data from the internet as fast as the Sunrise IDE or whatever from HD/CF it would be totally ok. I am not sure, if it makes sense to "combine" mass storage or network devices with the MP3 card, as it would require a lot of different combinations (MP3 with IDE, MP3 with Sd, MP3 with Ethernet etc etc...) The MSX should be fast enough to handle the transfer by itself and still has CPU power left.

By [D-Tail]

Ascended (8263)

27-02-2007, 16:35

Prodatron, let's not forget that Dumas isn't only Ethernet. It will also have some memory on it. I could imagine that some dedicated space could be implemented as a buffer for the MP3 device. As far as I have read in this thread, it's up to the coder to place MP3 data in the buffer. Well, I guess it can be done all-at-once, with some large buffer. Then, the MP3 processor would only receive an instruction to repeat the music data once it has played it all.

By DD

Expert (88)

27-02-2007, 17:30

@Prodatron, giving an interrupt earlier won't be a problem. The only disadvantage is, the MSX will have to send smaller data packages (6*256) more frequent. I will try to make the buffersize 10 or 11*256 bytes, i have to test it on the Turbo-R...

By Prodatron

Paragon (1839)

27-02-2007, 18:46

@DD: You are right, that would decrease the performance a little bit. But I hoped, that it won't be necessary to install an additional interrupt handler but to use the VDP 50/60Hz interrupt to send data to the MP3 card if required. I think sending 1,5KB at once (only every 4-5 vblanc for a 128kbps MP3) is still fine and not too small. Of course a bigger buffer would be always better.

@D-Tail: But the memory coming with Dumas is usual mapper-memory, isn't it? So it's not a difference to the MSX internal memory.
If I would implement a MP3 player, I would do it like this:
- reserving a buffer of let's say 16KB in the normal MSX memory
- load the first 8KB of the MP3 from HD into the first part of the buffer
- start sending the data of the first part to the MP3 card and load the second 8KB parallel
- wait until the first part has been sended
- now it will be just swapped. The second part is sent and the first part of the buffer can be filled with the next MP3 data
- etc etc.
I hope this won't generate any glitches, otherwise the size of the temporary buffer has to be increased.