Detailed Description

This class is intended for reading images from different sources.

The source can be:

Note

GStreamer-based pipeline is used for video decoding on Linux platforms. The support level of video formats depends on the set of installed GStreamer plugins.
GStreamer-based pipeline with NVIDIA hardware-accelerated codecs is used on NVIDIA Vibrante Linux platform only (V3L, V4L).
Pure NVIDIA hardware-accelerated decoding of H.264 elementary video streams is used on NVIDIA Vibrante Linux platforms (V3L, V4L).
OpenCV (FFmpeg back-end)-based pipeline is used for video decoding on Windows.
On Vibrante Linux, an active X session is required for FrameSource, because it uses EGL as an interop API.
Image decoding, image sequence decoding, and Video4Linux-compatible camera support require either OpenCV or GStreamer.
FrameSource is thread safe on all platforms except Vibrante Linux.

The URI-based scheme is used to describe data sources:

 <scheme>:///<host>[?<arg1=value1>&<arg2=value2>[&...]]

The scheme can be:

file - Specifies files on the local machine. The host is a path to the file or file sequence.
Note
The scheme can be omitted and you can specify a path to the file or file sequence directly.
device - Specifies camera devices. The possible <host> values:
- nvmedia - Specifies Omni Vision cameras. It contains two arguments:
  - config - The name of the configuration to use (see the table below).
  - number - The number of cameras to access. Can be 1, 2, or 4.
- v4l2 - Specifies V4L2-compatible cameras. It has a single argument:
  - index - The camera device ID to use.
- nvcamera - Specifies NVIDIA built-in cameras on Jetson TX1 boards.

Board name	Camera Interface	Camera Type	Configuration name
Jetson TK1 Pro	AB	OV10635	dvp-ov10635-yuv422-ab
Jetson TK1 Pro	CD	OV10635	dvp-ov10635-yuv422-cd
Jetson TK1 Pro	EF	OV10635	dvp-ov10635-yuv422-ef
DRIVE PX B00	AB	OV10635	dvp-ov10635-yuv422-ab-e2379
DRIVE PX B00	CD	OV10635	dvp-ov10635-yuv422-cd-e2379
DRIVE PX B00	EF	OV10635	dvp-ov10635-yuv422-ef-e2379
DRIVE PX B00	AB	OV10640	dvp-ov10640-raw12-ab-e2379
DRIVE CX	AB	OV10635	dvp-ov10635-yuv422-ab-p2382
DRIVE CX	AB	OV10640	dvp-ov10640-raw12-ab-p2382
E2580	EF	OV10635	dvp-ov10635-yuv422-ef-e2580

Functions
NVXIO_EXPORT std::unique_ptr < FrameSource >	nvxio::createDefaultFrameSource (vx_context context, const std::string &uri)
	FrameSource interface factory that provides appropriate implementation by source URI. More...

NVXIO_EXPORT vx_image	nvxio::loadImageFromFile (vx_context context, const std::string &fileName, vx_df_image format=VX_DF_IMAGE_RGB)
	Loads image from file into OpenVX Image object. More...

Function Documentation

NVXIO_EXPORT std::unique_ptr<FrameSource> nvxio::createDefaultFrameSource	(	vx_context	context,
		const std::string &	uri
	)

FrameSource interface factory that provides appropriate implementation by source URI.

Note

It supports the following image formats: PNG, JPEG, JPG, BMP, TIFF.
To read images from a sequence in which, for example, 0000.jpg corresponds to the first image, 0001.jpg - the second and so forth, use the path like this: path_to_folder/%04d.jpg
Use "device:///v4l2?index=0" path to capture images from the first camera. It supports only Video for Linux compatible cameras.
Use "device:///nvcamera" path to capture frames from NVIDIA GStreamer camera.
Use "device:///nvmedia?config=dvp-ov10635-yuv422-ab-e2379&number=4" path to capture frames from Omni Vision cameras via NvMedia.
Image decoding, image sequence decoding, and Video4Linux-compatible camera support require either OpenCV or GStreamer.
Support level of video formats depends on the set of installed GStreamer plugins.

Parameters

[in]	context	The context.
[in]	uri	A reference to the path to image source.

NVXIO_EXPORT vx_image nvxio::loadImageFromFile	(	vx_context	context,
		const std::string &	fileName,
		vx_df_image	format = `VX_DF_IMAGE_RGB`
	)

Loads image from file into OpenVX Image object.

The method is a wrapper around FrameSource to simplify single images loading.

Parameters