Encoder firmware API description
  ================================
  
  -------------------------------------------------------------------------------
  
  Name 	CX2341X_ENC_PING_FW
  Enum 	128/0x80
  Description
  	Does nothing. Can be used to check if the firmware is responding.
  
  -------------------------------------------------------------------------------
  
  Name 	CX2341X_ENC_START_CAPTURE
  Enum 	129/0x81
  Description
  	Commences the capture of video, audio and/or VBI data. All encoding
  	parameters must be initialized prior to this API call. Captures frames
  	continuously or until a predefined number of frames have been captured.
  Param[0]
  	Capture stream type:
  	    0=MPEG
  	    1=Raw
  	    2=Raw passthrough
  	    3=VBI
  
  Param[1]
  	Bitmask:
  	    Bit 0 when set, captures YUV
  	    Bit 1 when set, captures PCM audio
  	    Bit 2 when set, captures VBI (same as param[0]=3)
  	    Bit 3 when set, the capture destination is the decoder
  		(same as param[0]=2)
  	    Bit 4 when set, the capture destination is the host
  	Note: this parameter is only meaningful for RAW capture type.
  
  -------------------------------------------------------------------------------
  
  Name 	CX2341X_ENC_STOP_CAPTURE
  Enum 	130/0x82
  Description
  	Ends a capture in progress
  Param[0]
  	0=stop at end of GOP (generates IRQ)
  	1=stop immediate (no IRQ)
  Param[1]
  	Stream type to stop, see param[0] of API 0x81
  Param[2]
  	Subtype, see param[1] of API 0x81
  
  -------------------------------------------------------------------------------
  
  Name 	CX2341X_ENC_SET_AUDIO_ID
  Enum 	137/0x89
  Description
  	Assigns the transport stream ID of the encoded audio stream
  Param[0]
  	Audio Stream ID
  
  -------------------------------------------------------------------------------
  
  Name 	CX2341X_ENC_SET_VIDEO_ID
  Enum 	139/0x8B
  Description
  	Set video transport stream ID
  Param[0]
  	Video stream ID
  
  -------------------------------------------------------------------------------
  
  Name 	CX2341X_ENC_SET_PCR_ID
  Enum 	141/0x8D
  Description
  	Assigns the transport stream ID for PCR packets
  Param[0]
  	PCR Stream ID
  
  -------------------------------------------------------------------------------
  
  Name 	CX2341X_ENC_SET_FRAME_RATE
  Enum 	143/0x8F
  Description
  	Set video frames per second. Change occurs at start of new GOP.
  Param[0]
  	0=30fps
  	1=25fps
  
  -------------------------------------------------------------------------------
  
  Name 	CX2341X_ENC_SET_FRAME_SIZE
  Enum 	145/0x91
  Description
  	Select video stream encoding resolution.
  Param[0]
  	Height in lines. Default 480
  Param[1]
  	Width in pixels. Default 720
  
  -------------------------------------------------------------------------------
  
  Name 	CX2341X_ENC_SET_BIT_RATE
  Enum 	149/0x95
  Description
  	Assign average video stream bitrate. Note on the last three params:
  	Param[3] and [4] seem to be always 0, param [5] doesn't seem to be used.
  Param[0]
  	0=variable bitrate, 1=constant bitrate
  Param[1]
  	bitrate in bits per second
  Param[2]
  	peak bitrate in bits per second, divided by 400
  Param[3]
  	Mux bitrate in bits per second, divided by 400. May be 0 (default).
  Param[4]
  	Rate Control VBR Padding
  Param[5]
  	VBV Buffer used by encoder
  
  -------------------------------------------------------------------------------
  
  Name 	CX2341X_ENC_SET_GOP_PROPERTIES
  Enum 	151/0x97
  Description
  	Setup the GOP structure
  Param[0]
  	GOP size (maximum is 34)
  Param[1]
  	Number of B frames between the I and P frame, plus 1.
  	For example: IBBPBBPBBPBB --> GOP size: 12, number of B frames: 2+1 = 3
  	Note that GOP size must be a multiple of (B-frames + 1).
  
  -------------------------------------------------------------------------------
  
  Name 	CX2341X_ENC_SET_ASPECT_RATIO
  Enum 	153/0x99
  Description
  	Sets the encoding aspect ratio. Changes in the aspect ratio take effect
  	at the start of the next GOP.
  Param[0]
  	'0000' forbidden
  	'0001' 1:1 square
  	'0010' 4:3
  	'0011' 16:9
  	'0100' 2.21:1
  	'0101' reserved
  	 ....
  	'1111' reserved
  
  -------------------------------------------------------------------------------
  
  Name 	CX2341X_ENC_SET_DNR_FILTER_MODE
  Enum 	155/0x9B
  Description
  	Assign Dynamic Noise Reduction operating mode
  Param[0]
  	Bit0: Spatial filter, set=auto, clear=manual
  	Bit1: Temporal filter, set=auto, clear=manual
  Param[1]
  	Median filter:
  	    0=Disabled
  	    1=Horizontal
  	    2=Vertical
  	    3=Horiz/Vert
  	    4=Diagonal
  
  -------------------------------------------------------------------------------
  
  Name 	CX2341X_ENC_SET_DNR_FILTER_PROPS
  Enum 	157/0x9D
  Description
  	These Dynamic Noise Reduction filter values are only meaningful when
  	the respective filter is set to "manual" (See API 0x9B)
  Param[0]
  	Spatial filter: default 0, range 0:15
  Param[1]
  	Temporal filter: default 0, range 0:31
  
  -------------------------------------------------------------------------------
  
  Name 	CX2341X_ENC_SET_CORING_LEVELS
  Enum 	159/0x9F
  Description
  	Assign Dynamic Noise Reduction median filter properties.
  Param[0]
  	Threshold above which the luminance median filter is enabled.
  	Default: 0, range 0:255
  Param[1]
  	Threshold below which the luminance median filter is enabled.
  	Default: 255, range 0:255
  Param[2]
  	Threshold above which the chrominance median filter is enabled.
  	Default: 0, range 0:255
  Param[3]
  	Threshold below which the chrominance median filter is enabled.
  	Default: 255, range 0:255
  
  -------------------------------------------------------------------------------
  
  Name 	CX2341X_ENC_SET_SPATIAL_FILTER_TYPE
  Enum 	161/0xA1
  Description
  	Assign spatial prefilter parameters
  Param[0]
  	Luminance filter
  	    0=Off
  	    1=1D Horizontal
  	    2=1D Vertical
  	    3=2D H/V Separable (default)
  	    4=2D Symmetric non-separable
  Param[1]
  	Chrominance filter
  	    0=Off
  	    1=1D Horizontal (default)
  
  -------------------------------------------------------------------------------
  
  Name 	CX2341X_ENC_SET_VBI_LINE
  Enum 	183/0xB7
  Description
  	Selects VBI line number.
  Param[0]
  	Bits 0:4 	line number
  	Bit  31		0=top_field, 1=bottom_field
  	Bits 0:31 	all set specifies "all lines"
  Param[1]
  	VBI line information features: 0=disabled, 1=enabled
  Param[2]
  	Slicing: 0=None, 1=Closed Caption
  	Almost certainly not implemented. Set to 0.
  Param[3]
  	Luminance samples in this line.
  	Almost certainly not implemented. Set to 0.
  Param[4]
  	Chrominance samples in this line
  	Almost certainly not implemented. Set to 0.
  
  -------------------------------------------------------------------------------
  
  Name 	CX2341X_ENC_SET_STREAM_TYPE
  Enum 	185/0xB9
  Description
  	Assign stream type
  	Note: Transport stream is not working in recent firmwares.
  	And in older firmwares the timestamps in the TS seem to be
  	unreliable.
  Param[0]
  	 0=Program stream
  	 1=Transport stream
  	 2=MPEG1 stream
  	 3=PES A/V stream
  	 5=PES Video stream
  	 7=PES Audio stream
  	10=DVD stream
  	11=VCD stream
  	12=SVCD stream
  	13=DVD_S1 stream
  	14=DVD_S2 stream
  
  -------------------------------------------------------------------------------
  
  Name 	CX2341X_ENC_SET_OUTPUT_PORT
  Enum 	187/0xBB
  Description
  	Assign stream output port. Normally 0 when the data is copied through
  	the PCI bus (DMA), and 1 when the data is streamed to another chip
  	(pvrusb and cx88-blackbird).
  Param[0]
  	0=Memory (default)
  	1=Streaming
  	2=Serial
  Param[1]
  	Unknown, but leaving this to 0 seems to work best. Indications are that
  	this might have to do with USB support, although passing anything but 0
  	only breaks things.
  
  -------------------------------------------------------------------------------
  
  Name 	CX2341X_ENC_SET_AUDIO_PROPERTIES
  Enum 	189/0xBD
  Description
  	Set audio stream properties, may be called while encoding is in progress.
  	Note: all bitfields are consistent with ISO11172 documentation except
  	bits 2:3 which ISO docs define as:
  		'11' Layer I
  		'10' Layer II
  		'01' Layer III
  		'00' Undefined
  	This discrepancy may indicate a possible error in the documentation.
  	Testing indicated that only Layer II is actually working, and that
  	the minimum bitrate should be 192 kbps.
  Param[0]
  	Bitmask:
  	   0:1  '00' 44.1Khz
  		'01' 48Khz
  		'10' 32Khz
  		'11' reserved
  
  	   2:3  '01'=Layer I
  		'10'=Layer II
  
  	   4:7  Bitrate:
  		     Index | Layer I     | Layer II
  		     ------+-------------+------------
  		    '0000' | free format | free format
  		    '0001' |  32 kbit/s  |  32 kbit/s
  		    '0010' |  64 kbit/s  |  48 kbit/s
  		    '0011' |  96 kbit/s  |  56 kbit/s
  		    '0100' | 128 kbit/s  |  64 kbit/s
  		    '0101' | 160 kbit/s  |  80 kbit/s
  		    '0110' | 192 kbit/s  |  96 kbit/s
  		    '0111' | 224 kbit/s  | 112 kbit/s
  		    '1000' | 256 kbit/s  | 128 kbit/s
  		    '1001' | 288 kbit/s  | 160 kbit/s
  		    '1010' | 320 kbit/s  | 192 kbit/s
  		    '1011' | 352 kbit/s  | 224 kbit/s
  		    '1100' | 384 kbit/s  | 256 kbit/s
  		    '1101' | 416 kbit/s  | 320 kbit/s
  		    '1110' | 448 kbit/s  | 384 kbit/s
  		Note: For Layer II, not all combinations of total bitrate
  		and mode are allowed. See ISO11172-3 3-Annex B, Table 3-B.2
  
  	   8:9  '00'=Stereo
  		'01'=JointStereo
  		'10'=Dual
  		'11'=Mono
  		Note: the cx23415 cannot decode Joint Stereo properly.
  
  	  10:11 Mode Extension used in joint_stereo mode.
  		In Layer I and II they indicate which subbands are in
  		intensity_stereo. All other subbands are coded in stereo.
  		    '00' subbands 4-31 in intensity_stereo, bound==4
  		    '01' subbands 8-31 in intensity_stereo, bound==8
  		    '10' subbands 12-31 in intensity_stereo, bound==12
  		    '11' subbands 16-31 in intensity_stereo, bound==16
  
  	  12:13 Emphasis:
  		    '00' None
  		    '01' 50/15uS
  		    '10' reserved
  		    '11' CCITT J.17
  
  	  14 	CRC:
  		    '0' off
  		    '1' on
  
  	  15    Copyright:
  		    '0' off
  		    '1' on
  
  	  16    Generation:
  		    '0' copy
  		    '1' original
  
  -------------------------------------------------------------------------------
  
  Name 	CX2341X_ENC_HALT_FW
  Enum 	195/0xC3
  Description
  	The firmware is halted and no further API calls are serviced until the
  	firmware is uploaded again.
  
  -------------------------------------------------------------------------------
  
  Name 	CX2341X_ENC_GET_VERSION
  Enum 	196/0xC4
  Description
  	Returns the version of the encoder firmware.
  Result[0]
  	Version bitmask:
  	    Bits  0:15 build
  	    Bits 16:23 minor
  	    Bits 24:31 major
  
  -------------------------------------------------------------------------------
  
  Name 	CX2341X_ENC_SET_GOP_CLOSURE
  Enum 	197/0xC5
  Description
  	Assigns the GOP open/close property.
  Param[0]
  	0=Open
  	1=Closed
  
  -------------------------------------------------------------------------------
  
  Name 	CX2341X_ENC_GET_SEQ_END
  Enum 	198/0xC6
  Description
  	Obtains the sequence end code of the encoder's buffer. When a capture
  	is started a number of interrupts are still generated, the last of
  	which will have Result[0] set to 1 and Result[1] will contain the size
  	of the buffer.
  Result[0]
  	State of the transfer (1 if last buffer)
  Result[1]
  	If Result[0] is 1, this contains the size of the last buffer, undefined
  	otherwise.
  
  -------------------------------------------------------------------------------
  
  Name 	CX2341X_ENC_SET_PGM_INDEX_INFO
  Enum 	199/0xC7
  Description
  	Sets the Program Index Information.
  	The information is stored as follows:
  
  	struct info {
  		u32 length;		// Length of this frame
  		u32 offset_low;		// Offset in the file of the
  		u32 offset_high;	// start of this frame
  		u32 mask1;		// Bits 0-2 are the type mask:
  					// 1=I, 2=P, 4=B
  					// 0=End of Program Index, other fields
  					//   are invalid.
  		u32 pts;		// The PTS of the frame
  		u32 mask2;		// Bit 0 is bit 32 of the pts.
  	};
  	u32 table_ptr;
  	struct info index[400];
  
  	The table_ptr is the encoder memory address in the table were
  	*new* entries will be written. Note that this is a ringbuffer,
  	so the table_ptr will wraparound.
  Param[0]
  	Picture Mask:
  	    0=No index capture
  	    1=I frames
  	    3=I,P frames
  	    7=I,P,B frames
  	(Seems to be ignored, it always indexes I, P and B frames)
  Param[1]
  	Elements requested (up to 400)
  Result[0]
  	Offset in the encoder memory of the start of the table.
  Result[1]
  	Number of allocated elements up to a maximum of Param[1]
  
  -------------------------------------------------------------------------------
  
  Name 	CX2341X_ENC_SET_VBI_CONFIG
  Enum 	200/0xC8
  Description
  	Configure VBI settings
  Param[0]
  	Bitmap:
  	    0    Mode '0' Sliced, '1' Raw
  	    1:3  Insertion:
  		     '000' insert in extension & user data
  		     '001' insert in private packets
  		     '010' separate stream and user data
  		     '111' separate stream and private data
  	    8:15 Stream ID (normally 0xBD)
  Param[1]
  	Frames per interrupt (max 8). Only valid in raw mode.
  Param[2]
  	Total raw VBI frames. Only valid in raw mode.
  Param[3]
  	Start codes
  Param[4]
  	Stop codes
  Param[5]
  	Lines per frame
  Param[6]
  	Byte per line
  Result[0]
  	Observed frames per interrupt in raw mode only. Rage 1 to Param[1]
  Result[1]
  	Observed number of frames in raw mode. Range 1 to Param[2]
  Result[2]
  	Memory offset to start or raw VBI data
  
  -------------------------------------------------------------------------------
  
  Name 	CX2341X_ENC_SET_DMA_BLOCK_SIZE
  Enum 	201/0xC9
  Description
  	Set DMA transfer block size
  Param[0]
  	DMA transfer block size in bytes or frames. When unit is bytes,
  	supported block sizes are 2^7, 2^8 and 2^9 bytes.
  Param[1]
  	Unit: 0=bytes, 1=frames
  
  -------------------------------------------------------------------------------
  
  Name 	CX2341X_ENC_GET_PREV_DMA_INFO_MB_10
  Enum 	202/0xCA
  Description
  	Returns information on the previous DMA transfer in conjunction with
  	bit 27 of the interrupt mask. Uses mailbox 10.
  Result[0]
  	Type of stream
  Result[1]
  	Address Offset
  Result[2]
  	Maximum size of transfer
  
  -------------------------------------------------------------------------------
  
  Name 	CX2341X_ENC_GET_PREV_DMA_INFO_MB_9
  Enum 	203/0xCB
  Description
  	Returns information on the previous DMA transfer in conjunction with
  	bit 27 or 18 of the interrupt mask. Uses mailbox 9.
  Result[0]
  	Status bits:
  		0   read completed
  		1   write completed
  		2   DMA read error
  		3   DMA write error
  		4   Scatter-Gather array error
  Result[1]
  	DMA type
  Result[2]
  	Presentation Time Stamp bits 0..31
  Result[3]
  	Presentation Time Stamp bit 32
  
  -------------------------------------------------------------------------------
  
  Name 	CX2341X_ENC_SCHED_DMA_TO_HOST
  Enum 	204/0xCC
  Description
  	Setup DMA to host operation
  Param[0]
  	Memory address of link list
  Param[1]
  	Length of link list (wtf: what units ???)
  Param[2]
  	DMA type (0=MPEG)
  
  -------------------------------------------------------------------------------
  
  Name 	CX2341X_ENC_INITIALIZE_INPUT
  Enum 	205/0xCD
  Description
  	Initializes the video input
  
  -------------------------------------------------------------------------------
  
  Name 	CX2341X_ENC_SET_FRAME_DROP_RATE
  Enum 	208/0xD0
  Description
  	For each frame captured, skip specified number of frames.
  Param[0]
  	Number of frames to skip
  
  -------------------------------------------------------------------------------
  
  Name 	CX2341X_ENC_PAUSE_ENCODER
  Enum 	210/0xD2
  Description
  	During a pause condition, all frames are dropped instead of being encoded.
  Param[0]
  	0=Pause encoding
  	1=Continue encoding
  
  -------------------------------------------------------------------------------
  
  Name 	CX2341X_ENC_REFRESH_INPUT
  Enum 	211/0xD3
  Description
  	Refreshes the video input
  
  -------------------------------------------------------------------------------
  
  Name 	CX2341X_ENC_SET_COPYRIGHT
  Enum 	212/0xD4
  Description
  	Sets stream copyright property
  Param[0]
  	0=Stream is not copyrighted
  	1=Stream is copyrighted
  
  -------------------------------------------------------------------------------
  
  Name 	CX2341X_ENC_SET_EVENT_NOTIFICATION
  Enum 	213/0xD5
  Description
  	Setup firmware to notify the host about a particular event. Host must
  	unmask the interrupt bit.
  Param[0]
  	Event (0=refresh encoder input)
  Param[1]
  	Notification 0=disabled 1=enabled
  Param[2]
  	Interrupt bit
  Param[3]
  	Mailbox slot, -1 if no mailbox required.
  
  -------------------------------------------------------------------------------
  
  Name 	CX2341X_ENC_SET_NUM_VSYNC_LINES
  Enum 	214/0xD6
  Description
  	Depending on the analog video decoder used, this assigns the number
  	of lines for field 1 and 2.
  Param[0]
  	Field 1 number of lines:
  	    0x00EF for SAA7114
  	    0x00F0 for SAA7115
  	    0x0105 for Micronas
  Param[1]
  	Field 2 number of lines:
  	    0x00EF for SAA7114
  	    0x00F0 for SAA7115
  	    0x0106 for Micronas
  
  -------------------------------------------------------------------------------
  
  Name 	CX2341X_ENC_SET_PLACEHOLDER
  Enum 	215/0xD7
  Description
  	Provides a mechanism of inserting custom user data in the MPEG stream.
  Param[0]
  	0=extension & user data
  	1=private packet with stream ID 0xBD
  Param[1]
  	Rate at which to insert data, in units of frames (for private packet)
  	or GOPs (for ext. & user data)
  Param[2]
  	Number of data DWORDs (below) to insert
  Param[3]
  	Custom data 0
  Param[4]
  	Custom data 1
  Param[5]
  	Custom data 2
  Param[6]
  	Custom data 3
  Param[7]
  	Custom data 4
  Param[8]
  	Custom data 5
  Param[9]
  	Custom data 6
  Param[10]
  	Custom data 7
  Param[11]
  	Custom data 8
  
  -------------------------------------------------------------------------------
  
  Name 	CX2341X_ENC_MUTE_VIDEO
  Enum 	217/0xD9
  Description
  	Video muting
  Param[0]
  	Bit usage:
  	 0    	'0'=video not muted
  		'1'=video muted, creates frames with the YUV color defined below
  	 1:7  	Unused
  	 8:15 	V chrominance information
  	16:23 	U chrominance information
  	24:31 	Y luminance information
  
  -------------------------------------------------------------------------------
  
  Name 	CX2341X_ENC_MUTE_AUDIO
  Enum 	218/0xDA
  Description
  	Audio muting
  Param[0]
  	0=audio not muted
  	1=audio muted (produces silent mpeg audio stream)
  
  -------------------------------------------------------------------------------
  
  Name 	CX2341X_ENC_SET_VERT_CROP_LINE
  Enum 	219/0xDB
  Description
  	Something to do with 'Vertical Crop Line'
  Param[0]
  	If saa7114 and raw VBI capture and 60 Hz, then set to 10001.
  	Else 0.
  
  -------------------------------------------------------------------------------
  
  Name 	CX2341X_ENC_MISC
  Enum 	220/0xDC
  Description
  	Miscellaneous actions. Not known for 100% what it does. It's really a
  	sort of ioctl call. The first parameter is a command number, the second
  	the value.
  Param[0]
  	Command number:
  	 1=set initial SCR value when starting encoding (works).
  	 2=set quality mode (apparently some test setting).
  	 3=setup advanced VIM protection handling.
  	   Always 1 for the cx23416 and 0 for cx23415.
  	 4=generate DVD compatible PTS timestamps
  	 5=USB flush mode
  	 6=something to do with the quantization matrix
  	 7=set navigation pack insertion for DVD: adds 0xbf (private stream 2)
  	   packets to the MPEG. The size of these packets is 2048 bytes (including
  	   the header of 6 bytes: 0x000001bf + length). The payload is zeroed and
  	   it is up to the application to fill them in. These packets are apparently
  	   inserted every four frames.
  	 8=enable scene change detection (seems to be a failure)
  	 9=set history parameters of the video input module
  	10=set input field order of VIM
  	11=set quantization matrix
  	12=reset audio interface after channel change or input switch (has no argument).
  	   Needed for the cx2584x, not needed for the mspx4xx, but it doesn't seem to
  	   do any harm calling it regardless.
  	13=set audio volume delay
  	14=set audio delay
  
  Param[1]
  	Command value.