MVD Services

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This is for using the MVD hardware video decoder(unknown whether MVD can do more than decoding) + hardware color-format converter. The New_3DS Internet Browser uses mvd:STD for video decoding + YUV2RGB for decoded MJPEG frames.

See here for the supported hardware decoder video codecs.

A maximum of 4 sessions can be opened at a time, for all of these services combined.

MVD Service "mvd:STD"

Command Header Available since system version Description
0x00010082 Initialize
0x00020000 Shutdown
0x00030300 CalculateWorkBufSize
0x00050100 (u8 unk0, u8 unk1, u8 unk2, u8 unk3) SKATER uses value 0 for all of these params.
0x00080142 DecodeFrame
0x00090042 (u8 unkval, val0, kprocess handle) This writes some state beginning at cmdreply[2]. unkval is normally 0, when preparing to shutdown MVD unkval is 1.
0x001A0000 Used when doing color-format conversion.
0x001B0040 (u8 unknown) SKATER uses value 1 for this.
0x001D0042 GetConfig
0x001E0044 SetConfig

This one uses the I/O mapped @ 0x10207000.

This service is used by the New_3DS Internet Browser.

By default MVD does(?) various post-processing with the output image, this is controlled by the configuration. This post-processing isn't done at all in certain cases. By default MVD will align the output frame width to 512, by writing zero-value pixels.

Initialization procedures:

Shutdown procedures:

  • MJPEG: just use command 0x00190000, then MVDSTD:Shutdown.
  • H.264: Use command 0x00090042 in a loop, waiting for it to return a retval that isn't 0x00017002. Then use commands 0x001C0000, 0x00190000, and 0x00070000. Then use MVDSTD:Shutdown.

MVD Service "l2b:u"

This one uses the I/O mapped @ 0x10130000.

MVD Service "l2b2:u"

This uses the same command-handler as "l2b:u".

MVD Service "y2r2:u"

This one uses the I/O mapped @ 0x10102000.

MVD Result-codes

Result-code Internal MVD status-code Description
0xD961710F Invalid configuration, mainly when setting the config.