V4L2 Video Converter

Detailed Description

NVIDIA Tegra V4L2 Video Converter Description and Extensions.

Use the video converter for color space conversion, scaling, and conversion between hardware buffer memory (V4L2_MEMORY_MMAP/V4L2_MEMORY_DMABUF), software buffer memory (V4L2_MEMORY_USERPTR), and other operations such as cropping, flipping/rotating, and temporal noise reduction (TNR). The video converter device node is "/dev/nvhost-vic".

Supported Pixelformats

PIXEL FORMAT	PIXEL FORMAT
V4L2_PIX_FMT_YUV444M	V4L2_PIX_FMT_YVU422M
V4L2_PIX_FMT_YUV420M	V4L2_PIX_FMT_YVU420M
V4L2_PIX_FMT_NV12M	V4L2_PIX_FMT_GREY
V4L2_PIX_FMT_YUYV	V4L2_PIX_FMT_YVYU
V4L2_PIX_FMT_UYVY	V4L2_PIX_FMT_VYUY
V4L2_PIX_FMT_ABGR32	V4L2_PIX_FMT_XBGR32

Supported Pixel Formats for TNR

PIXEL FORMAT	PIXEL FORMAT
V4L2_PIX_FMT_YUV420M	V4L2_PIX_FMT_NV12M
V4L2_PIX_FMT_UYVY	V4L2_PIX_FMT_YUYV

Supported Memory Types

MEMORY	OUTPUT PLANE	CAPTURE PLANE
V4L2_MEMORY_MMAP	Y	Y
V4L2_MEMORY_DMABUF	Y	Y
V4L2_MEMORY_USERPTR	Y	Y

Supported Controls

• V4L2_CID_VIDEO_CONVERT_OUTPUT_PLANE_LAYOUT
• V4L2_CID_VIDEO_CONVERT_CAPTURE_PLANE_LAYOUT
• V4L2_CID_VIDEO_CONVERT_FLIP_METHOD
• V4L2_CID_VIDEO_CONVERT_INTERPOLATION_METHOD
• V4L2_CID_VIDEO_CONVERT_TNR_ALGORITHM

Cropping

Video converter supports cropping using VIDIOC_S_SELECTION IOCTL with type V4L2_BUF_TYPE_VIDEO_CAPTURE and target V4L2_SEL_TGT_CROP. This must be set before requesting buffers on either plane.

EOS Handling

The following sequence must be followed for sending EOS and recieving EOS from the converter.

1. Send EOS to converter by queueing on the output plane a buffer with bytesused = 0 for the 0th plane (v4l2_buffer.m.planes[0].bytesused = 0).
2. Dequeues buffers on the capture plane until it gets a buffer with bytesused = 0 for the 0th plane.

Note

Currently, V4L2 plugins do not support odd resolution.

Macros
#define	V4L2_CID_VIDEO_CONVERT_OUTPUT_PLANE_LAYOUT   (V4L2_CID_MPEG_BASE+520)
	Defines the Control ID to set converter output plane buffer layout. More...
#define	V4L2_CID_VIDEO_CONVERT_CAPTURE_PLANE_LAYOUT   (V4L2_CID_MPEG_BASE+521)
	Defines the Control ID to set converter capture plane buffer layout. More...
#define	V4L2_CID_VIDEO_CONVERT_FLIP_METHOD   (V4L2_CID_MPEG_BASE+522)
	Defines the Control ID to set the converter flip/rotation method. More...
#define	V4L2_CID_VIDEO_CONVERT_INTERPOLATION_METHOD   (V4L2_CID_MPEG_BASE+523)
	Defines the Control ID to set the converter interpolation method. More...
#define	V4L2_CID_VIDEO_CONVERT_TNR_ALGORITHM   (V4L2_CID_MPEG_BASE+524)
	Defines the Control ID to set the converter Temporal Noise Reduction (TNR) algorithm. More...

Enumerations
enum	v4l2_nv_buffer_layout {   V4L2_NV_BUFFER_LAYOUT_PITCH = 0,   V4L2_NV_BUFFER_LAYOUT_BLOCKLINEAR = 1 }
	Enum specifying types of buffer layouts. More...
enum	v4l2_flip_method {   V4L2_FLIP_METHOD_IDENTITY = 0,   V4L2_FLIP_METHOD_90L = 1,   V4L2_FLIP_METHOD_180 = 2,   V4L2_FLIP_METHOD_90R = 3,   V4L2_FLIP_METHOD_HORIZ = 4,   V4L2_FLIP_METHOD_INVTRANS = 5,   V4L2_FLIP_METHOD_VERT = 6,   V4L2_FLIP_METHOD_TRANS = 7 }
	Specifies the types of rotation/flip algorithms. More...
enum	v4l2_interpolation_method {   V4L2_INTERPOLATION_NEAREST = 1,   V4L2_INTERPOLATION_LINEAR = 2,   V4L2_INTERPOLATION_SMART = 3,   V4L2_INTERPOLATION_BILINEAR = 4 }
	Specifies the types of interpolation methods. More...
enum	v4l2_tnr_algorithm {   V4L2_TNR_ALGO_ORIGINAL = 0,   V4L2_TNR_ALGO_OUTDOOR_LOW_LIGHT = 1,   V4L2_TNR_ALGO_OUTDOOR_MEDIUM_LIGHT = 2,   V4L2_TNR_ALGO_OUTDOOR_HIGH_LIGHT = 3,   V4L2_TNR_ALGO_INDOOR_LOW_LIGHT = 4,   V4L2_TNR_ALGO_INDOOR_MEDIUM_LIGHT = 5,   V4L2_TNR_ALGO_INDOOR_HIGH_LIGHT = 6 }
	Specifies the types of TNR algorithms. More...

Macro Definition Documentation

#define V4L2_CID_VIDEO_CONVERT_CAPTURE_PLANE_LAYOUT   (V4L2_CID_MPEG_BASE+521)

Defines the Control ID to set converter capture plane buffer layout.

A value of type v4l2_nv_buffer_layout must be supplied with this control.

Attention

This control must be set before requesting buffers on the capture plane.

Definition at line 575 of file v4l2_nv_extensions.h.

#define V4L2_CID_VIDEO_CONVERT_FLIP_METHOD   (V4L2_CID_MPEG_BASE+522)

Defines the Control ID to set the converter flip/rotation method.

A value of type v4l2_flip_method must be supplied with this control.

Attention

This control must be set before requesting buffers on either plane.

Definition at line 584 of file v4l2_nv_extensions.h.

#define V4L2_CID_VIDEO_CONVERT_INTERPOLATION_METHOD   (V4L2_CID_MPEG_BASE+523)

Defines the Control ID to set the converter interpolation method.

A value of type v4l2_interpolation_method must be supplied with this control.

Attention

This control must be set before requesting buffers on either plane.

Definition at line 593 of file v4l2_nv_extensions.h.

#define V4L2_CID_VIDEO_CONVERT_OUTPUT_PLANE_LAYOUT   (V4L2_CID_MPEG_BASE+520)

Defines the Control ID to set converter output plane buffer layout.

A value of type v4l2_nv_buffer_layout must be supplied with this control.

Attention

This control must be set before requesting buffers on the output plane.

Definition at line 566 of file v4l2_nv_extensions.h.

#define V4L2_CID_VIDEO_CONVERT_TNR_ALGORITHM   (V4L2_CID_MPEG_BASE+524)

Defines the Control ID to set the converter Temporal Noise Reduction (TNR) algorithm.

A value of type v4l2_tnr_algorithm must be supplied with this control.

Attention

This control must be set before requesting buffers on either plane.

TNR algorithms are not supported with YUV422 and YUV444 capture plane formats.

Definition at line 604 of file v4l2_nv_extensions.h.

Enumeration Type Documentation

enum v4l2_flip_method

Specifies the types of rotation/flip algorithms.

Enumerator
V4L2_FLIP_METHOD_IDENTITY	Identity (no rotation).
V4L2_FLIP_METHOD_90L	Rotate counter-clockwise 90 degrees.
V4L2_FLIP_METHOD_180	Rotate 180 degrees.
V4L2_FLIP_METHOD_90R	Rotate clockwise 90 degrees.
V4L2_FLIP_METHOD_HORIZ	Flip horizontally.
V4L2_FLIP_METHOD_INVTRANS	Flip across upper right/lower left diagonal.
V4L2_FLIP_METHOD_VERT	Flip vertically.
V4L2_FLIP_METHOD_TRANS	Flip across upper left/lower right diagonal.

Definition at line 1525 of file v4l2_nv_extensions.h.

enum v4l2_interpolation_method

Specifies the types of interpolation methods.

Enumerator
V4L2_INTERPOLATION_NEAREST	Nearest interpolation method.
V4L2_INTERPOLATION_LINEAR	Linear interpolation method.
V4L2_INTERPOLATION_SMART	Smart interpolation method.
V4L2_INTERPOLATION_BILINEAR	Bi-Linear interpolation method.

Definition at line 1539 of file v4l2_nv_extensions.h.

enum v4l2_nv_buffer_layout

Enum specifying types of buffer layouts.

Enumerator
V4L2_NV_BUFFER_LAYOUT_PITCH	Pitch Linear Layout.
V4L2_NV_BUFFER_LAYOUT_BLOCKLINEAR	Block Linear Layout.

Definition at line 1517 of file v4l2_nv_extensions.h.

enum v4l2_tnr_algorithm

Specifies the types of TNR algorithms.

Enumerator
V4L2_TNR_ALGO_ORIGINAL	Default TNR algorithm.
V4L2_TNR_ALGO_OUTDOOR_LOW_LIGHT	Outdoor Low Light TNR algorithm.
V4L2_TNR_ALGO_OUTDOOR_MEDIUM_LIGHT	Outdoor Medium Light TNR algorithm.
V4L2_TNR_ALGO_OUTDOOR_HIGH_LIGHT	Outdoor High Light TNR algorithm.
V4L2_TNR_ALGO_INDOOR_LOW_LIGHT	Indoor Low Light TNR algorithm.
V4L2_TNR_ALGO_INDOOR_MEDIUM_LIGHT	Indoor Medium Light TNR algorithm.
V4L2_TNR_ALGO_INDOOR_HIGH_LIGHT	Indoor High Light TNR algorithm.

Definition at line 1549 of file v4l2_nv_extensions.h.