Re: [alsa-devel] DSD over HDMI: audio data packetization

Andrej,

I have a slight doubt about "KSDATAFORMAT_SUBTYPE_IEC61937_ONE_BIT_AUDIO".

To be concise "IEC61937_ONE_BIT_AUDIO"

I do not have all IEC 61937 specs, I can not find "IEC61937_ONE_BIT_AUDIO" in the list below.

Part 1: General Part 2: Burst-info Part 3: Non-linear PCM bitstreams according to the AC-3 format Part 4: Non-linear PCM bitstreams according to the MPEG audio format Part 5: Non-linear PCM bitstreams according to the DTS (Digital Theater Systems) format(s) Part 6: Non-linear PCM bitstreams according to the MPEG-2 AAC and MPEG-4 AAC audio formats Part 7: Non-linear PCM bitstreams according to the ATRAC, ATRAC2/3 and ATRAC-X formats Part 8: Non-linear PCM bitstreams according to the Windows Media Audio (WMA) Professional format Part 9: Non-linear PCM bitstreams according to the MAT format Part 10: Non-linear PCM bitstreams according to the MPEG-4 audio lossless coding (ALS) format - Edition 1.0 Part 11: MPEG-4 AAC and its extensions in LATM/LOAS Part 12: Non-linear PCM bitstreams according to the DRA formats

Thanks.

On Tue, 2015-01-06 at 17:33 +1300, Andrej Falout wrote:

Hi Anssi,

Just wondering how Microsoft documentation fits into this discussion:

"Representing Formats for IEC 61937 Transmissions"

http://msdn.microsoft.com/en-us/library/windows/desktop/dd316761% 28v=vs.85%29.aspx

"Microsoft-provided HD Audio class driver supports PCM, AC3, DTS, AAC, Dolby Digital Plus, WMA Pro, MAT(MLP) formats. The GUIDs for the compressed audio formats that are not supported by the HD audio class driver and can be implemented by third-party solutions are listed in the following table. "

 CEA 861 Type
SubFormat GUID
  Description

0x08 00000008-0cea-0010-8000-00aa00389b71

KSDATAFORMAT_SUBTYPE_IEC61937_ATRAC

Adaptive Transform Acoustic Coding (ATRAC) 0x09 00000009-0cea-0010-8000-00aa00389b71

KSDATAFORMAT_SUBTYPE_IEC61937_ONE_BIT_AUDIO

One-Bit Audio 0x0d 0000000d-0cea-0010-8000-00aa00389b71

KSDATAFORMAT_SUBTYPE_IEC61937_DST

Direct Stream Transport (DST)—lossless compressed DSD (Direct Stream Digital).

And knowing that IEC 61937 from HDMI 1.3 also supports above 6.144 Mbps...

Is there a doubt that above information is correct, and that DST/DST can be carried over 61937 in Microsoft HDA class driver, in this example, by "implementing a third-party solution" as described in this table?

Thanks,

Andrej Falout

On Mon, Jan 5, 2015 at 4:46 PM, Anssi Hannula anssi.hannula@iki.fi wrote: 04.01.2015, 05:10, Xuebing Wang kirjoitti: > Anssi, Libin, > > Thanks for your help. > > After a little bit of research, I do think it is possible to stream DSD > over HDMI (the mechanism is as Anssi mentioned, similar way as HBR). > > Please see HDA spec: > 3.7.1 Stream Format Structure > (If the TYPE is set to Non-PCM, the controller just pushes data over the > link and is not concerned > with formatting. The base rate, data type, and number of Words (MULT) to > send each valid frame > are specified to control the rate at which the non-PCM data is sent.) > > 7.3.3.8 Converter Format > > What do you think? In order to implement this similiar mechanism > (similar to HBR), I still have some detailed questions that I will write > in another email. Thanks.

    That setting will still not allow you to send One-bit audio or
    DST
    packets. The stream will still be encapsulated in either ASP
    or HBR
    packets, depending on the value of the EPT field (Encoded
    Packet Type,
    7.3.3.13).


    >
    > On Thu, 2015-01-01 at 06:37 +0200, Anssi Hannula wrote:
    >> 01.01.2015, 04:07, Yang, Libin kirjoitti:
    >>> Hi,
    >>>
    >>>> -----Original Message-----
    >>>> From: Anssi Hannula [mailto:anssi.hannula@iki.fi]
    >>>> Sent: Wednesday, December 31, 2014 11:45 PM
    >>>> To: Xuebing Wang
    >>>> Cc: Yang, Libin; alsa-devel@alsa-project.org; Lin,
    Mengdong; ; Takashi Iwai; ;
    >>>> Wu Fengguang
    >>>> Subject: Re: [alsa-devel] DSD over HDMI: audio data
    packetization
    >>>>
    >>>> 31.12.2014, 17:38, Xuebing Wang kirjoitti:
    >>>>> Anssi, Libin,
    >>>>>
    >>>>> Thank you very much for your help.
    >>>>>
    >>>>> If L-PCM audio data packetization is done by hardware,
    is it possible
    >>>>> to implement DSD over HDMI on Intel integrated graphics?
    Thanks again.
    >>>>
    >>>> I don't think so, unless:
    >>>>
    >>>> (a) It is possible to somehow encapsulate the stream in
    Audio Sample
    >>>> Packets and be accepted by the receiver (like e.g. AC3,
    DTS). I'm not aware of
    >>>> such a way.
    >>>>
    >>>> or:
    >>>> (b) There is some undocumented feature in the Intel HDMI
    codecs allowing
    >>>> the driver to switch to DSD or driver-constructed packets
    (instead of
    >>>> ASP) in similar way as there is a way to switch to HBR
    packets.
    >>>>
    >>>
    >>> Yes, I agree. And I'm not sure whether HDMI spec supports
    DSD.
    >>
    >> It does, via the "One Bit Audio" and "DST" formats (spec
    5.3.9, 5.3.10
    >> in 1.3a/1.4a).
    >
    >



    --
    Anssi Hannula