Rockbox General > Rockbox General Discussion

Which sound format uses CPU the least?

(1/4) > >>

r00tb33r:
I'm thinking of adding music support to rockdoom and would like to know which sound format would use the least CPU cycles.
I'm thinking WAV, but I would also want to know the optimal bitrate and sampling rate that would require the least conversion (basically a sound map that can be fed directly to the interface, without a codec).
Any ideas?

saratoga:
The playback engine runs at 44.1kHz. 

dreamlayers:
Plugins can use any available sampling rate.  Rockdoom uses 11025 Hz when that is available.  Otherwise it uses 44100 Hz.

r00tb33r:

--- Quote from: dreamlayers on April 12, 2009, 12:20:51 AM ---Plugins can use any available sampling rate.  Rockdoom uses 11025 Hz when that is available.  Otherwise it uses 44100 Hz.

--- End quote ---

How do I know which sampling rate say Gigabeat rockdoom uses?



...
There might be a slight problem with WAV as I have just converted the Doom 2 music I had to 16bit @ 44100Hz and it came out as 783MB total, which is likely unacceptable to most people.

How CPU intensive is MidiPlay?  Ideally from software design standpoint the port of doom should rely on the resources in the WAD, but how likely is it that the midi patchset(s) we have will produce decent sounding result?
The recordings I have were recorded from a Roland MIDI card which sounds pretty much ideal, but the size in WAV format is unacceptable.

I gave the Doom 2 MIDIs a listen with the patchset available on the MidiPlay wiki page, and it does sound like Doom music, but well, unsatisfying.  Sure this might be sufficient to add support for MIDI music in doom, but I would prefer to try some more patchsets.
A quick Google search returned a ton and a half of dead links...  Anyone know places to get patchsets?

dreamlayers:

--- Quote from: r00tb33r on April 12, 2009, 01:00:54 AM ---How do I know which sampling rate say Gigabeat rockdoom uses?

--- End quote ---

You can look at the configuration header file for your player.  For example, if you mean Gigabeat F, that would be firmware/export/config-gigabeat.h.  There, search for HW_SAMPR_CAPS.  For the Gigabeat F, that is:

--- Code: ---#define HW_SAMPR_CAPS (SAMPR_CAP_88 | SAMPR_CAP_44 | SAMPR_CAP_22 | \
                       SAMPR_CAP_11)

--- End code ---
SAMPR_CAP_11 means 11 KHz, or more accurately 11025 Hz.  Since that is present, Rockdoom will use it.  If it wasn't there, Rockdoom would use 44100 Hz.   


--- Quote from: r00tb33r on April 12, 2009, 01:00:54 AM ---There might be a slight problem with WAV as I have just converted the Doom 2 music I had to 16bit @ 44100Hz and it came out as 783MB total, which is likely unacceptable to most people.

--- End quote ---

Well, you could resample it and cut the size to 1/4 of that.  Considering the number of tracks and how Doom only needs 8 MB RAM on a PC, a target with 32 MB might even have enough memory to load the whole track at once.

I'd still rather see compression.  FLAC is rather fast, see:
http://www.rockbox.org/twiki/bin/view/Main/CodecPerformanceComparison
Shorten (SHN) ought to be even faster and simpler to decode.

I can't answer the question on MidiPlay, because I've never used it.

Navigation

[0] Message Index

[#] Next page