Gst-nvvideo4linux2¶
DeepStream extends the open source V4L2 codec plugins (here called Gst-v4l2) to support hardware-accelerated codecs.
Decoder¶
The OSS Gst-nvvideo4linux2 plugin leverages the hardware decoding engines on Jetson and DGPU platforms by interfacing with libv4l2 plugins on those platforms. It supports H.264, H.265, JPEG and MJPEG formats. The plugin accepts an encoded bitstream and uses the NVDEC hardware engine to decode the bitstream. The decoded output can be NV12 or YUV444 format which depends on the encoded stream content.
Note
When you use the v4l2 decoder for decoding JPEG images, you must use the open source jpegparse plugin before the decoder to parse encoded JPEG images.
Inputs and Outputs¶
Inputs
An encoded bitstream. Supported formats are H.264, H.265, JPEG and MJPEG
H264 encoded bitstream in 8bit 4:2:0 format.
H265 encoded bitstream in 8/10/12 bit 4:2:0 and 8/10/12 bit 4:4:4 format.
Control Parameters
gpu-id
num-extra-surfaces
skip-frames
cudadec-memtype
drop-frame-interval
low-latency-mode
Output
H264 decoder outputs GstBuffer in 8bit semi-planar(NV12) 4:2:0 format.
H265 decoder outputs GstBuffer in 8/10/12 bit semi-planar(NV12) 4:2:0 format, 8/10/12 bit planar(YUV444) 4:4:4 format.
Features¶
The following table summarizes the features of the Gst-nvvideo4linux2 decoder plugin.
Feature |
Description |
|---|---|
Supports H.264 decode |
h264 encoded bitstream is decoded into 8bit NV12 |
Supports H.265 decode |
h265 encoded bitstream is decoded into 8/10/12 bit NV12 or 8/10/12 bit YUV444 depending on the stream content |
Supports JPEG/MJPEG decode |
— |
User-configurable CUDA memory type (Pinned/Device/Unified) for output buffers |
— |
Note
10/12bit YUV444 format support is applicable only for x86/dGPU platforms.
Also, for 12bit NV12 format, the output caps shows I420_12LE. But the data is handled as semiplanar 12 bit data. This is a workaround since gstreamer v1.16 does not have the particular caps for 12 bit NV12. Downstream component should process it considering as 12bit NV12 only.
Gst Properties¶
The following table summarizes the Gst properties of the Gst-nvvideo4linux2 decoder plugin.
Property |
Meaning |
Type and Range |
Example/Notes |
Platforms |
|---|---|---|---|---|
gpu-id |
Device ID of GPU to use for decoding. |
Integer, 0 to 4,294,967,295 |
gpu-id=0 |
dGPU |
num-extra-surfaces |
Number of surfaces in addition to min decode surfaces given by the V4L2 driver. |
Integer, 1 to 24 |
num-extra-surfaces=24 Default: 0 |
dGPU Jetson |
skip-frames |
Type of frames to skip during decoding. Represented internally by enum SkipFrame. 0 (decode_all): decode all frames 1 (decode_non_ref): skips non-ref frames (Applicable only on Jetson platform) 2 (decode_key): decode key frames |
Integer, 0, 1, or 2 |
skip-frames=0 Default: 0 |
dGPU Jetson |
drop-frame-interval |
Interval to drop the frames, e.g. a value of 5 means the decoder outputs every fifth frame, and others are dropped. |
Integer, 1 to 30 |
Default: 0 |
dGPU Jetson |
cudadec-memtype |
Memory type for CUDA decoder buffers. Represented internally by enum CudaDecMemType. 0 (memtype_device): Device 1 (memtype_pinned): Host Pinned 2 (memtype_unified): Unified |
Integer, 0, 1, or 2 |
cuda-memory-type=1 Default: 2 |
dGPU |
low-latency-mode |
Set low latency mode for bitstreams having I and IPPP frames with no B frames |
Boolean |
Default: false |
dGPU |
Encoder¶
The OSS Gst-nvvideo4linux2 plugin leverages the hardware accelerated encoding engine available on Jetson and dGPU platforms by interfacing with libv4l2 plugins on those platforms. The plugin accepts RAW data in I420/NV12 or YUV444 format. It uses the NVENC hardware engine to encode RAW input. Encoded output is in elementary bitstream supported format. To set appropriate tuning-info-id and preset-id properties please refer to Nvidia Video Codec SDK Documentation at https://docs.nvidia.com/video-technologies/video-codec-sdk/nvenc-preset-migration-guide/index.html
Inputs and Outputs¶
Inputs
RAW input in I420/NV12 or YUV444 format
8 bit I420/NV12 and YUV444 raw formats
8/10 bit I420/NV12 and YUV444 raw formats
Control parameters
gpu-id (dGPU only)
profile
bitrate
control-rate
iframeinterval
preset-id
tuning-info-id
copy-meta
Output
Gst Buffer with encoded output in H264 and H265 format.
Features¶
The following table summarizes the features of the Gst-nvvideo4linux2 encoder plugin.
Feature |
Description |
|---|---|
Supports H.264 encode |
8 bit I420/NV12, 8bit YUV444 raw format can be encoded into h264 bitstream |
Supports H.265 encode |
8/10 bit I420/NV12, 8/10 bit YUV444 raw format can be encoded into h265 bitstream |
Note
8/10bit YUV444 format support is applicable only for x86/dGPU platforms.
Gst Properties¶
The following table summarizes the Gst properties of the Gst-nvvideo4linux2 encoder plugin.
Property |
Meaning |
Type and Range |
Example/Notes |
Platforms |
|---|---|---|---|---|
gpu-id |
Device ID of GPU to used. |
Integer, 0 to 4,294,967,295 |
gpu-id=0 |
dGPU |
bitrate |
Sets bitrate for encoding, in bits/seconds. |
Integer, 0 to 4,294,967,295 |
Default:4000000 |
dGPU Jetson |
iframeinterval |
Encoding intra-frame occurrence frequency. |
Integer, 0 to 4,294,967,295 |
Default: 30 |
dGPU Jetson |
force-idr |
Force an IDR frame |
Boolean |
Default: false |
dGPU |
Profile |
H.264/H.265 encoder profile; represented internally by enum GstV4l2VideoEncProfileType. For H.264: 0 (GST_V4L2_H264_VIDENC_BASELINE_PROFILE): Baseline 2 (GST_V4L2_H264_VIDENC_MAIN_PROFILE): Main 4 (GST_V4L2_H264_VIDENC_HIGH_PROFILE): High For H.265: 0 (GST_V4L2_H265_VIDENC_MAIN_PROFILE): Main 1 (GST_V4L2_H265_VIDENC_MAIN10_PROFILE): Main10 |
Values of enum GstV4l2VideoEncProfileType |
Default Baseline Default: 0 |
dGPU Jetson |
preset-id |
Sets CUVID Preset ID for Encoder |
Integer, 1 to 7 |
Default: 1 |
dGPU |
tuning-info-id |
Sets Tuning Info Preset for encoder; represented internally by enum GstV4l2VideoEncTuingInfoPreset. (1): HighQualityPreset - Tuning Preset for High Quality (2): LowLatencyPreset - Tuning Preset for Low Latency (3): UltraLowLatencyPreset - Tuning Preset for Low Latency (4): LosslessPreset - Tuning Preset for Lossless |
Values of enum GstV4L2VideoEncTuingInfoPreset |
Default LowLatencyPreset Default: 2 |
dGPU |
copy-meta |
Copies input metadata on output buffer |
Boolean |
Default: false |
dGPU Jetson |
qp-range |
Sets quantization paramenter range for P, I and B frame |
String, 1 to 51 |
Default: null |
dGPU Jetson |