Lossless Audio in Games

[JAGUAR1977]

Am I correct in thinking any game that shows up on my reciever as Multi Channel PCM 5.1/7.1 are lossless?

I just switched my PS3 over to optical and it then showed up as DD 5.1 for GT5P.

I don't have many games so was suprised to see most demos, other than LEGO Indiana Jones, were Multi Channel PCM, so presumably lossless audio?

[WriteSimply]

Yep, though technically it's UNCOMPRESSED PCM. The audio has to be MIXED according to the action on/off the screen, which means the mixing has to be done with lossless sound elements. Once that is done (very quickly and on the fly), the game's audio signal is sent out. If PS3 is set to HDMI Multichannel-PCM, it'll be uncompressed PCM. If the PS3 is set to optical, the audio signal has to be encoded as Dolby Digital or DTS signal before being sent out.


fuad

[Getus]

This is verry intresting
What type of audio does gta4 have?
On my onkyo is shows as 7.1 pcm but the rear surround speaker don't do a thing.
And is sounds verry soft.

On the XBM is olso shows as 7.1 pcm but only my fronts are putting out sound.

But when i play for example oblivion it shows 7.1 pcm and every speaker is putting out sound. And on Devil may Cry 4 is shows as 5.1 dd.
can someone explain?

[saprano]

Originally Posted by JAGUAR1977

Am I correct in thinking any game that shows up on my reciever as Multi Channel PCM 5.1/7.1 are lossless?

I just switched my PS3 over to optical and it then showed up as DD 5.1 for GT5P.

I don't have many games so was suprised to see most demos, other than LEGO Indiana Jones, were Multi Channel PCM, so presumably lossless audio?

Originally Posted by WriteSimply

Yep, though technically it's UNCOMPRESSED PCM. The audio has to be MIXED according to the action on/off the screen, which means the mixing has to be done with lossless sound elements. Once that is done (very quickly and on the fly), the game's audio signal is sent out. If PS3 is set to HDMI Multichannel-PCM, it'll be uncompressed PCM. If the PS3 is set to optical, the audio signal has to be encoded as Dolby Digital or DTS signal before being sent out.


fuad

ummm no......all games are not lossless.
the reason your seeing "multichannel PCM" is because the ps3 is decoding dolby digital, or dts and is sending it out as PCM. if you want the receiver to decode those sound formats uncheck dts, and dolby in the ps3 sound options then you will see the lights come on for those formats. now for some games you dont have to do that,the receiver automatically deocodes them. but for most the ps3 docodes. so unless the game was made to be uncompressed,your seeing "multichannel PCM" because the ps3 is docoding the sound.

[WriteSimply]

Originally Posted by saprano

ummm no......all games are not lossless.

You must know something that I don't. How do multichannel audio gets mixed before being encoded as DD/DTS?


fuad

[saprano]

The only games i know that are lossless are the ones made by sony,like warhawk.the OP asked if all games are lossless...there not.the OP said he's seeing mutichannel PCM on his receiver with most games,thats because the ps3 is decoding the sound,uncheck DD or DTS and see what happens.....thers only a handfull of games thats uncompressed.

[WriteSimply]

Originally Posted by saprano

The only games i know that are lossless are the ones made by sony,like warhawk.the OP asked if all games are lossless...there not.the OP said he's seeing mutichannel PCM on his receiver with most games,thats because the ps3 is decoding the sound,uncheck DD or DTS and see what happens.....thers only a handfull of games thats uncompressed.

I explained this in a long forgotten thread about a year ago...

For a movie soundtrack like Transformers, sound elements are assembled and then mixed according to the action on the screen. The final mix is the uncompressed MPCM version. The TrueHD on BD is the lossless version; the DD version on BD is the lossy version. Regardless, both encodings happened AFTER the final mixing.

A game "soundtrack" is very much like mixing for a movie, except that all the mixing has to be done on the fly; the sound elements and score are stored on the HDD. The final mix is then sent out as uncompressed MPCM via HDMI delivery or encoded as DD/DTS for optical connections.

The OP confuses the matter because he mentioned Multichannel PCM and Optical in his post without indicating if he switched from HDMI to optical.


fuad

[Getus]

Originally Posted by Getus

On my onkyo is shows as 7.1 pcm but the rear surround speaker don't do a thing.

Could someone explain to me how this is possible?

[WriteSimply]

Originally Posted by Getus

Could someone explain to me how this is possible?

The HDMI connection SUPPORTS 7.1 audio. Doesn't mean that the game/movie HAS 7.1 audio to output.


fuad

[Kenshiro]

Originally Posted by Getus

Could someone explain to me how this is possible?

His PS3 is set to output 7.1 audio but the game only supports 5.1 audio.

There are however a lot of PS3 games that do support 7.1 LPCM... as I recently learned. Whether or not the audio is compressed on the disc and only being output as LPCM, or if it is just left uncompressed to begin with is unknown to me since developers do not list audio specs. I don't see why they would have to compress it though with all the extra space on the Blu-ray disc.. and due to the fact that streaming uncompressed audio frees up processing power that would be otherwise spent on uncompressing the data.

[Getus]

Yes that is understandeble. But
It shows on the disply (with some games and on the xmb) as 7.1 pcm. But the xmb is 2.1/2.0 and the games are 5.1.

So wy is it showing as 7.1.

Because if a movie is 5.1 it shows as 5.1.

[Kenshiro]

Originally Posted by Getus

Yes that is understandeble. But
It shows on the disply (with some games and on the xmb) as 7.1 pcm. But the xmb is 2.1/2.0 and the games are 5.1.

So wy is it showing as 7.1.

Because if a movie is 5.1 it shows as 5.1.

Thats just how the PS3 works, the receiver will show what ever the PS3 tells it show in the audio options. If you were to go into the options and deselect the 7.1 audio options then your receiver will show 5.1. Then your receiver could matrix audio into the 2 rear channels if you wanted to hear audio from them.

[Getus]

i thought it has to do something with the ps3. But i find is strange that when a game (not all) are 5.1 it still shows as 7.1. and it doesn't with movies.

But fore example Devil May Cry 4 it only shows as dd 5.1. and offcourse the rear surround speaker do not give a sound.

The link in this thread it great (wich games are 7.1 and wich are not) the games who are not 7.1 still show as 7.1.

but i guess it can't be helpt.
Thank you all for the info

[Kenshiro]

Originally Posted by Getus

i thought it has to do something with the ps3. But i find is strange that when a game (not all) are 5.1 it still shows as 7.1. and it doesn't with movies.

But fore example Devil May Cry 4 it only shows as dd 5.1. and offcourse the rear surround speaker do not give a sound.

The link in this thread it great (wich games are 7.1 and wich are not) the games who are not 7.1 still show as 7.1.

but i guess it can't be helpt.
Thank you all for the info

Yeah, it is strange that some games don't tell the PS3 which audio track it supports properly.. thats why its good to know which games support 7.1 and which ones do not.

[saprano]

Originally Posted by WriteSimply

I explained this in a long forgotten thread about a year ago...

For a movie soundtrack like Transformers, sound elements are assembled and then mixed according to the action on the screen. The final mix is the uncompressed MPCM version. The TrueHD on BD is the lossless version; the DD version on BD is the lossy version. Regardless, both encodings happened AFTER the final mixing.

A game "soundtrack" is very much like mixing for a movie, except that all the mixing has to be done on the fly; the sound elements and score are stored on the HDD. The final mix is then sent out as uncompressed MPCM via HDMI delivery or encoded as DD/DTS for optical connections.

The OP confuses the matter because he mentioned Multichannel PCM and Optical in his post without indicating if he switched from HDMI to optical.


fuad

I know all that. the point im trying to make is not all games are lossless,thats it.

just because he's seeing mutichannel pcm on his AV does not mean the soundtrack is uncompressed.

and yes now im confused.

[icewind]

Uncharted have PCM surround

[zweet77]

Originally Posted by WriteSimply

I explained this in a long forgotten thread about a year ago...

For a movie soundtrack like Transformers, sound elements are assembled and then mixed according to the action on the screen. The final mix is the uncompressed MPCM version. The TrueHD on BD is the lossless version; the DD version on BD is the lossy version. Regardless, both encodings happened AFTER the final mixing.

A game "soundtrack" is very much like mixing for a movie, except that all the mixing has to be done on the fly; the sound elements and score are stored on the HDD. The final mix is then sent out as uncompressed MPCM via HDMI delivery or encoded as DD/DTS for optical connections.

The OP confuses the matter because he mentioned Multichannel PCM and Optical in his post without indicating if he switched from HDMI to optical.


fuad

I think that cutscenes and musical scores are part of a final mix that was made for the game.As far as I know the only games that have uncompressed sound are Sony first party titles from the likes of Insomniac(Ratchet and Clank and Resistance)and Naughty Dog(Uncharted)Games like Devil may cry have Dolby.So for games like those It is the ps3 that is decoding it to pcm.The audio codec is usually on the back of the game just like movies although I think some don't have the info because game devolopers may not be required to provide it like movie studios are.

[Kenshiro]

Originally Posted by zweet77

I think that cutscenes and musical scores are part of a final mix that was made for the game.As far as I know the only games that have uncompressed sound are Sony first party titles from the likes of Insomniac(Ratchet and Clank and Resistance)and Naughty Dog(Uncharted)Games like Devil may cry have Dolby.So for games like those It is the ps3 that is decoding it to pcm.The audio codec is usually on the back of the game just like movies although I think some don't have the info because game devolopers may not be required to provide it like movie studios are.

I'm aware that most games only contain one compressed audio track that the PS3 decodes and outputs as PCM over HDMI. However, games like Uncharted have dolby digital, DTS, and LPCM tracks.. so just because you see a dolby or DTS logo doesn't necessarily mean that there is not a LPCM track on the disc also.

My question is concerning the 50+ PS3 games that support discrete 7.1 audio.. If there is only one audio track on the disc that is compressed, wouldn't the developers have to be using some type of lossy 7.1 compression codec like Dolby Digital Plus or DTS-HD, or are they allowed to just add two more channels to a standard DD 5.1 or a DTS 5.1 track? With all the extra space on the Blu-ray, wouldn't it be easier to just use 7.1 LPCM which is free? I'm curious...

[WriteSimply]

Originally Posted by zweet77

I think that cutscenes and musical scores are part of a final mix that was made for the game.

Cut-scenes and scores are pre-mixed audio. There's no need to mix them on the fly, even if the video is not pre-rendered.

So for games like those It is the ps3 that is decoding it to pcm.

You still don't understand the concept of mixing the audio. So let's do a reverse engineering. Take any game audio that has is output via optical in Dolby Digital and DTS. Before your receiver can decode that DD/DTS bitstream into 5.1/7.1 channels, it has to RECEIVE that un-decoded bitstream first. That bitstream comes from the PS3, which ENCODES the DD/DTS bitstream on the fly. But how do you think it does the encoding? Do you think all of the sound effects of gunshots, grunts, cars passing by are pre-mixed and pre-encoded?

Like I said earlier, it is easier for the PS3 to assemble the audio elements in PCM and output it as PCM than having to allocate processing power to encode 5.1/7.1 the lossy DD/DTS mix. Plus with PCM, you get uncompressed lossless audio.

Originally Posted by Kenshiro

My question is concerning the 50+ PS3 games that support discrete 7.1 audio.. If there is only one audio track on the disc that is compressed, wouldn't the developers have to be using some type of lossy 7.1 compression codec like Dolby Digital Plus or DTS-HD, or are they allowed to just add two more channels to a standard DD 5.1 or a DTS 5.1 track? With all the extra space on the Blu-ray, wouldn't it be easier to just use 7.1 LPCM which is free? I'm curious...

DD+ and DTS HD of over 5.1 can't be transmitted over optical because it consumes too much bandwith. DD and DTS have a maximum of 6.1 channels (DTS-ES Discrete has a discrete channel while DD Ex has a matrixed channel) that can be transmitted over optical.

For games supporting 7.1 audio, the extra channel is just mixed into the 5.1 mix for optical playback. If you're outputting multichannel PCM via HDMI, then you get the full 7.1 audio.


fuad

[saprano]

Originally Posted by WriteSimply

Cut-scenes and scores are pre-mixed audio. There's no need to mix them on the fly, even if the video is not pre-rendered.

You still don't understand the concept of mixing the audio. So let's do a reverse engineering. Take any game audio that has is output via optical in Dolby Digital and DTS. Before your receiver can decode that DD/DTS bitstream into 5.1/7.1 channels, it has to RECEIVE that un-decoded bitstream first. That bitstream comes from the PS3, which ENCODES the DD/DTS bitstream on the fly. But how do you think it does the encoding? Do you think all of the sound effects of gunshots, grunts, cars passing by are pre-mixed and pre-encoded?

Like I said earlier, it is easier for the PS3 to assemble the audio elements in PCM and output it as PCM than having to allocate processing power to encode 5.1/7.1 the lossy DD/DTS mix. Plus with PCM, you get uncompressed lossless audio.

You see now i dont understand.....if the game is lossy DD,or DTS,how is it uncompressed?

what im trying to say is almost all games the OP is seeing on his AV as mutichannel PCM is because the ps3 is decoding it. are you saying the sound gets uncompressed first then compressed again?