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directshow_h264_video_decoder

nanocosmos H.264 Video Decoder Filter​

Module / Version​

nanocosmos H.264/AVC Direct Show Video Decoder Filter\ nh264dec.ax Version 2.5.2.4

The nanocosmos H.264/AVC Video Decoder support streams in baseline, main and high profile. It is highly optimized for use on hyper-threading and multi core systems.

Connectivity​

The input is accepting connections to splitter filters or combined source/splitter filters matching the following media types:

Major types:

  • MEDIATYPE_Video

Subtypes:

  • FourCCs:
    • H264, h264,
    • AVC1, avc1,
    • X264, x264,
    • VSSH, vssh,
    • MEDIASUBTYPE_H264: {8D2D71CB-243F-45E3-B2D8-5FD7967EC09B}

Formats:

  • FORMAT_VideoInfo,
  • FORMAT_VideoInfo2,
  • FORMAT_MPEG2_VIDEO

The output supports these media types:

Major types:

  • MEDIATYPE_Video

Subtypes:

  • MEDIASUBTYPE_YV12,
  • MEDIASUBTYPE_I420,
  • MEDIASUBTYPE_IYUV,
  • MEDIASUBTYPE_YUY2,
  • MEDIASUBTYPE_RGB24,
  • MEDIASUBTYPE_RGB32,
  • MEDIASUBTYPE_ARGB32,
  • MEDIASUBTYPE_RGB565,

Formats:

  • FORMAT_VideoInfo
  • FORMAT_VideoInfo2

Filter GUIDs​

//%% Filter GUID
//%% {264DA7DD-CE74-472d-A2FD-796A1F0A379C}
DEFINE_GUID(CLSID_NANO_H264_DECODER, 0x264DA7DD, 0xCE74, 0x472d, 0xA2, 0xFD, 0x79, 0x6A, 0x1F, 0x0A, 0x37, 0x9C);

//%% Configuration interface ICodecProp
//%% {0F817204-82C8-4c12-884A-F45FB2F33A6E}
DEFINE_GUID(IID_ICodecProp, 0xf817204, 0x82c8, 0x4c12, 0x88, 0x4a, 0xf4, 0x5f, 0xb2, 0xf3, 0x3a, 0x6e);

//%% ICodecProp: IID_nanoPeg_LicenseString
//%% type: BSTR / Unicode string
//%% Set license string to unlock filter
//%% {1788F0B0-5985-4a19-B7FE-8AAC1BFC14B3}
DEFINE_GUID(IID_nanoPeg_LicenseString, 0x1788f0b0, 0x5985, 0x4a19, 0xb7, 0xfe, 0x8a, 0xac, 0x1b, 0xfc, 0x14, 0xb3);

Setting the license to unlock filter​

The filter can be unlocked either through a license key entry in the windows registry or by setting the license key through COM interface ICodecProp::SetProperty with the property IID_nanoPeg_LicenseString as first parameter.

The second license parameter has to be a wide/unicode string!

Decoder Configuration Registry Settings​

The decoder is able to perform an adaptive frame dropping and deblocking depending on the quality / delay messages received from the downstream renderer filter.

Key: 

HKEY_CURRENT_USER\Software\nanocosmos\nh264dec

Frame dropping / skipping mode​

Determines the behaviour in the case of timing / performance problems.

  • Value name: DroppingMode
  • Value type: REG_DWORD
  • Valid values:
    • 0 - no frames are skipped
    • 1 - skip non reference frames only (B-frames)
    • 2 - skip non intra frames only (P- and B-frames), default value

Deblocking mode​

Determines the deblocking behaviour.

  • Value name: DeblockingMode
  • Value type: REG_DWORD
  • Valid values:
    • 0 - disable deblocking
    • 1 - auto, decoder will reduce deblocking temporarily in the case of performance problems, default value
    • 2 - always perform full deblocking
    • 3 - always perform deblocking on reference frames only

Output color space selection​

Forces the filter to use a desired output color format. If no or no valid value is set, the output color format will be negotiated with the downstream renderer filter (usually YV12).

  • Value name: ForceOutputFourCC
  • Value type: REG_SZ / String
  • Valid values:
    • YV12,
    • I420,
    • IYUV,
    • YUY2,
    • RGB32,
    • RGB24,
    • RGB565,
    • ARGB32

Deinterlacing Mode​

Determines the deinterlacing behaviour.

  • Value name: DeinterlacingMode
  • Value type: REG_DWORD
  • Valid values:
    • 0 - disabled
    • 1 - duplicate, default value
    • 2 - blend
    • 3 - median
    • 4 - edge detection
    • 5 - median threshold
    • 6 - content adaptive vertical temporal

DirectShow Editing Services (DES) Return Mode​

Receive returns HRESULT error values if Deliver fails. Needs to be enabled for DES.

  • Value name: DESReturnMode
  • Value type: REG_DWORD
  • Valid values:
    • 0 - disabled, default value
    • 1 - enabled

Threading Mode​

Determines the threading behaviour. Auto detection or number of decoding threads.

  • Value name: DESReturnMode
  • Value type: REG_DWORD
  • Valid values:
    • 0 - auto detect number of cpus, __default value__
    • 1-8 - set number of decoding threads

Output resolution alignment​

Determines the alignment of the output resolution, to adjust it to multiples of this value.

  • Value name: OutputAlignment
  • Value type: REG_DWORD
  • Valid values:
    • 1-16, __default value:__ 4

Debug-Log Configuration Registry Settings​

Key: 

HKEY_CURRENT_USER\Software\DebugNano\nh264dec.ax

File name​

Sets the output file name. The folder must already exist.

  • Value name: LogToFile
  • Value type: REG_SZ / String
  • Valid values: a valid output file name to enable file logging or an empty string

Logging level​

A higher value increases the amount of logging messages sent, and messages get more detailed.

  • Value name: TRACE
  • Value type: REG_DWORD
  • Valid values:
    • 0 - minimal logging
    • …
    • 9 - maximal logging
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